Endangered and Threatened Wildlife and Plants; Removing the Greater Yellowstone Ecosystem Population of Grizzly Bears From the Federal List of Endangered and Threatened Wildlife

DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R6-ES-2016-0042; FXES11130900000C6-156-FF09E42000]

RIN 1018-BA41

Endangered and Threatened Wildlife and Plants; Removing the Greater Yellowstone Ecosystem Population of Grizzly Bears From the Federal List of Endangered and Threatened Wildlife

AGENCY:

Fish and Wildlife Service, Interior.

ACTION:

Proposed rule; availability of draft Grizzly Bear Recovery Plan Supplement: Revised Demographic Criteria and draft 2016 Conservation Strategy, and announcement of public informational meetings and hearings.

SUMMARY:

The best available scientific and commercial data indicate that the Greater Yellowstone Ecosystem (GYE) population of grizzly bears (

Ursus arctos horribilis

) has recovered and no longer meets the definition of an endangered or threatened species under the Endangered Species Act, as amended (Act). The United States Fish and Wildlife Service (Service) is also proposing to identify the GYE grizzly bear population as a distinct population segment (DPS). Therefore, we, the Service propose to revise the List of Endangered and Threatened Wildlife, under the authority of the Act, by removing the GYE population. The Service has determined that the GYE grizzly bear population has increased in size and more than tripled its occupied range since being listed as threatened under the Act in 1975 and that threats to the population are sufficiently minimized. The participating States of Idaho, Montana, and Wyoming must adopt the necessary post-delisting management objectives, which adequately ensure that the GYE population of grizzly bears remains recovered, into enforceable regulations before the Service will proceed with a final delisting rule.

DATES:

Written comments:

We will accept comments received or postmarked on or before May 10, 2016. Comments submitted electronically using the Federal eRulemaking Portal (see

ADDRESSES

, below) must be received by 11:59 p.m. Eastern Time on the closing date.

Public informational meetings and public hearings:

We will hold two public informational meetings and public hearings on the following dates:

○ On April 11, 2016, in Cody, Wyoming. The public informational meeting will run from 2 p.m. to 4 p.m., and the public hearing will run from 5 p.m. to 8 p.m.

○ On April 12, 2016, in Bozeman, Montana. The public informational meeting will run from 2 p.m. to 4 p.m., and the public hearing will run from 5 p.m. to 8 p.m.

ADDRESSES:

Written comments:

You may submit written comments by any one of the following methods:

•

Electronically:

Go to the Federal eRulemaking Portal:

http://www.regulations.gov.

In the Search box, enter Docket No. FWS-R6-ES-2016-0042, which is the docket number for this rulemaking. Then, click on the Search button. On the resulting page, in the Search panel on the left side of the screen, under the Document Type heading, click on the Proposed Rules link to locate this document. You may submit a comment by clicking on the blue “Comment Now!” box. If your comments will fit in the provided comment box, please use this feature of

http://www.regulations.gov

, as it is most compatible with our comment review procedures. If you attach your comments as a separate document, our preferred file format is Microsoft Word. If you attach multiple comments (such as form letters), our preferred format is a spreadsheet in Microsoft Excel.

•

By hard copy:

Submit by U.S. mail or hand-delivery to: Public Comments Processing, Attn: Docket No. FWS-R6-ES-2016-0042, U.S. Fish and Wildlife Service, MS: BPHC, 5275 Leesburg Pike, Falls Church, VA 22041-3803.

•

At a public informational meeting or public hearing.

We will accept written comments at either of the public informational meetings or public hearings. See details on the dates of the public informational meetings and public hearings in

DATES

; the addresses are listed below.

We request that you submit written comments only by the methods described above. We will post all comments on

http://www.regulations.gov.

This generally means that we will post any personal information you provide us (see Information Requested, below, for more details).

Public informational meetings and public hearings:

We will hold two public informational meetings and public hearings at the following locations:

○ Holiday Inn, 5 East Baxter Lane, Bozeman, MT 59715.

○ Holiday Inn, 1701 Sheridan Ave., Cody, WY 82414.

More information on the public informational meetings and public hearings is provided under Public Informational Meetings and Public Hearings, below.

Document availability:

This proposed rule and all supporting documents are available on

http://www.regulations.gov.

In addition, certain documents such as the draft 2016 Conservation Strategy, the draft Grizzly Bear Recovery Plan Supplement: Revised Demographic Criteria, and all references cited are available at

http://www.fws.gov/mountain-prairie/es/grizzlyBear.php.

FOR FURTHER INFORMATION CONTACT:

Dr. Christopher Servheen, Grizzly Bear Recovery Coordinator, U.S. Fish and Wildlife Service, University Hall, Room #309, University of Montana, Missoula, MT 59812; telephone 406-243-4903; facsimile 406-243-3212. For Tribal inquiries, contact Ivy Allen, Native American Liaison, U.S. Fish and Wildlife Service; telephone: 303-236-4575. Persons who use a telecommunications device for the deaf (TDD) may call the Federal Information Relay Service (FIRS) at 800-877-8339.

SUPPLEMENTARY INFORMATION:

Table of Contents

Executive Summary

Greater Yellowstone Ecosystem (GYE)

Previous Federal Actions

Information Requested

Peer Review

Public Informational Meetings and Public Hearings

Taxonomy and Species Description

Behavior and Life History

Nutritional Ecology

Habitat Management

Population Ecology—Background

Recovery Planning and Implementation

—Background

—Recovery Planning

—Habitat-Based Recovery Criteria

—Suitable Habitat

—Population and Demographic Recovery Criteria

○ Demographic Recovery Criterion 1

○ Demographic Recovery Criterion 2

○ Demographic Recovery Criterion 3

—The Conservation Strategy

Distinct Vertebrate Population Segment Policy Overview

Past Practice and History of Using DPSs

Distinct Vertebrate Population Segment Analysis

—Analysis of Discreteness in Relation to Remainder of Taxon

—Analysis of Significance of Population Segment to Taxon

○ Unusual or Unique Ecological Setting

○ Significant Gap in the Range of the Taxon

○ Marked Genetic Differences

Summary of Distinct Population Segment Analysis

Summary of Factors Affecting the Species

—Factor A. The Present or Threatened Destruction, Modification, or Curtailment of Its Habitat or Range

○ Habitat Management Inside the Primary Conservation Area

Motorized Access Management

Developed Sites

Livestock Allotments

Mineral and Energy Development

Recreation

Snowmobiling

Vegetation Management

Climate Change

Habitat Fragmentation

○ Habitat Management Outside the Primary Conservation Area

○ Summary of Factor A

—Factor B. Overutilization for Commercial, Recreational, Scientific, or Educational Purposes

○ Summary of Factor B

—Factor C. Disease or Predation

○ Disease

○ Natural Predation

○ Human-Caused Mortality

○ Summary of Factor C

—Factor D. Inadequacy of Existing Regulatory Mechanisms

○ Forest Service

○ National Park Service

○ Tribal Lands

○ State Regulatory Mechanisms

○ Summary of Factor D

—Factor E. Other Natural or Manmade Factors Affecting Its Continued Existence

○ Genetic Health

○ Changes in Food Resources

○ Climate Change

○ Public Support and Human Attitudes

○ Summary of Factor E

—Cumulative Effects of Factors A Through E

Summary of Factors Affecting the Greater Yellowstone Ecosystem Grizzly Bear Population

Proposed Determination

Significant Portion of Its Range Analysis

—Background

—SPR Analysis for the GYE Grizzly Bear DPS

Effects of the Rule

Post-Delisting Monitoring

—Monitoring

—Triggers for a Biology and Monitoring Review by the IGSBT

—Triggers for a Service Status Review

Required Determinations

—Clarity of the Rule

—National Environmental Policy Act

—Government-to-Government Relationships With Tribes

Glossary

References Cited

Authors

Executive Summary

(1) Purpose of the Regulatory Action

Section 4 of the Act and its implementing regulations (50 CFR part 424) set forth the procedures for revising the Federal Lists of Endangered and Threatened Wildlife and Plants. Rulemaking is required to remove a species from the Federal Lists of Endangered and Threatened Wildlife and Plants. Accordingly, we are issuing this proposed rule to identify the Greater Yellowstone Ecosystem (GYE) grizzly bear DPS and revise the List of Endangered and Threatened Wildlife. The population is stable, threats are sufficiently minimized, and a post-delisting monitoring and management framework has been developed and will be incorporated into regulatory documents. The best scientific and commercial data available, including our detailed evaluation of information related to the population's trend and structure, indicate that the distinct population segment of grizzly bears in the GYE has recovered and threats have been reduced such that this DPS no longer meets the definition of threatened, or endangered, under the Act. To ensure consistency in management approaches regardless of listed status, concurrent with publication of this proposed rule, we are releasing a draft supplement to the 1993 Recovery Plan's demographic recovery criteria for this population of grizzly bears and a draft of the 2016 Conservation Strategy for public comment. If we finalize this proposal to identify the GYE DPS and remove that DPS from the List of Endangered and Threatened Wildlife, there would be no change to the threatened status of the remaining grizzly bears in the lower 48 States, which would remain protected by the Act.

(2) Major Provision of the Regulatory Action

This proposed action is authorized by the Act. We are proposing to amend § 17.11(h), subchapter B of chapter I, title 50 of the Code of Federal Regulations by revising the listing for “Bear, grizzly” under “Mammals” in the List of Endangered and Threatened Wildlife to remove the GYE grizzly bear DPS.

(3) Costs and Benefits

We have not analyzed the costs or benefits of this rulemaking action because the Act precludes consideration of such impacts on listing and delisting determinations. Instead, listing and delisting decisions are based solely on the best scientific and commercial information available regarding the status of the subject species.

Greater Yellowstone Ecosystem (GYE)

The Greater Yellowstone Ecosystem (GYE) refers to the larger ecological system containing and surrounding Yellowstone National Park. The GYE includes portions of five National Forests; Yellowstone National Park, Grand Teton National Park, and the John D. Rockefeller Memorial Parkway (administered by Grand Teton National Park); and State, Tribal, and private lands. While there is no distinct boundary to the GYE, it is generally defined as those lands surrounding Yellowstone National Park with elevations greater than 1,500 meters (m) (4,900 feet (ft)) (see USDA Forest Service 2004, p. 46; Schwartz

et al.

2006

b

, p. 9). While we consider the terms “Greater Yellowstone Area” and “Greater Yellowstone Ecosystem” to be interchangeable, we use GYE in this proposed rule to be consistent with the draft 2016 Conservation Strategy.

Previous Federal Actions

On July 28, 1975, we published a rule to designate the grizzly bear as threatened in the conterminous (lower 48) United States (40 FR 31734). Accordingly, we developed a Grizzly Bear Recovery Plan (U.S. Fish and Wildlife Service 1982) and updated that plan as necessary (72 FR 11376, March 13, 2007; U.S. Fish and Wildlife Service 1993, 2007

a

, 2007

b

). The designation of the grizzly bear as a threatened species in the conterminous United States and subsequent development of the 1982 and 1993 Recovery Plans occurred before the publication of our DPS policy on February 7, 1996 (61 FR 4722). The 1993 Recovery Plan identifies distinct Recovery Zones and unique demographic parameters for six different grizzly bear populations with the intent that these individual populations would be delisted as they each achieve recovery (U.S. Fish and Wildlife Service 1993, pp. ii, 33-34). On November 17, 2005, we proposed to designate the GYE population of grizzly bears as a DPS and to remove this DPS from the Federal List of Endangered and Threatened Wildlife (70 FR 69854). This proposal had a 120-day comment period (70 FR 69854, November 17, 2005; 71 FR 8251, February 16, 2006), during which we held two public hearings and four open houses (70 FR 69854, November 17, 2005; 71 FR 4097, January 25, 2006). On March 29, 2007, we finalized this proposed action, designating the GYE population as a DPS and removing grizzly bears in the GYE from the Federal List of Endangered and Threatened Wildlife (72 FR 14866). This final determination was vacated by the District Court of Montana on September 21, 2009, in

Greater Yellowstone Coalition

v.

Servheen, et al.,

672 F.Supp.2d 1105 (D. Mont. 2009). The District Court ruled against the Service on two of the four points brought against them, that the Service was arbitrary and capricious in its evaluation of whitebark pine and that

the identified regulatory mechanisms were inadequate because they were not legally enforceable. In compliance with this order, the GYE grizzly bear population was once again made a threatened population under the Act (16 U.S.C. 1531

et seq.

) (see 75 FR 14496; March 26, 2010), and the Service withdrew the delisting rule. By vacating the Service's rule, the District Court mooted two other lawsuits challenging the rule. Neither of these lawsuits were decided on the merits. The United States appealed the District Court decision, on November 15, 2011, the Ninth Circuit Court of Appeals issued an opinion affirming in part and reversing in part the district court's decision vacating the final rule delisting grizzly bears in the Greater Yellowstone Ecosystem (

Greater Yellowstone Coalition

v.

Servheen, et al.,

665 F.3d 105 (9th Cir. 2011)). The Ninth Circuit ruled that the Service's final rule did have adequate regulatory mechanisms but did not adequately explain why the loss of whitebark pine was not a threat to the GYE grizzly bear population. In compliance with this order, the GYE population of grizzly bears remained federally listed as “threatened” under the Act, and the Interagency Grizzly Bear Study Team (IGBST) initiated more thorough research into the potential impact of whitebark pine decline on GYE grizzly bears.

Information Requested

We intend that any final action resulting from this proposal will be based on the best available scientific and commercial data and will be as accurate and as effective as possible. Therefore, we invite Tribal and governmental agencies, the scientific community, industry, and other interested parties to submit comments or recommendations concerning any aspect of this proposed rule, the draft 2016 Conservation Strategy, and the draft Grizzly Bear Recovery Plan Supplement: Revised Demographic Criteria for the Greater Yellowstone Ecosystem. Comments should be as specific as possible.

To issue a final rule to implement this proposed action, we will take into consideration all comments and any additional information we receive. Such communications may lead to a final rule that differs from this proposal.

You may submit your comments and materials concerning the proposed rule by one of the methods listed in

ADDRESSES

. Comments must be submitted to

http://www.regulations.gov

before 11:59 p.m. (Eastern Time) on the date specified in

DATES

. We will consider any and all comments received, or mailed comments that are postmarked, by the date specified in

DATES

.

We will post your entire comment—including your personal identifying information—on

http://www.regulations.gov.

If you provide personal identifying information in your comment, you may request at the top of your document that we withhold this information from public review. However, we cannot guarantee that we will be able to do so.

Comments and materials we receive, as well as supporting documentation we used in preparing this proposed rule, will be available for public inspection on

http://www.regulations.gov

, or by appointment, during normal business hours at our Missoula office (see

FOR FURTHER INFORMATION CONTACT

).

Peer Review

In accordance with our policy, “Notice of Interagency Cooperative Policy for Peer Review in Endangered Species Act Activities,” which was published on July 1, 1994 (59 FR 34270), we will seek the expert opinion of at least three appropriate specialists who are independent of the Service, the States, and the Interagency Grizzly Bear Study Team (IGBST) regarding scientific data and interpretations contained in this proposed rule. Those experts will each submit separate opinions for the Service to consider. We will send copies of this proposed rule, the draft 2016 Conservation Strategy, and the draft Grizzly Bear Recovery Plan Supplement: Revised Demographic Criteria to the peer reviewers immediately following publication of this proposed rule in the

Federal Register

. The purpose of such review is to ensure that our decisions are based on scientifically sound data, assumptions, and analysis. Accordingly, the final rule and decision may differ from this proposal.

Public Informational Meetings and Public Hearings

We are holding two public informational meetings and public hearings on the dates listed above in

DATES

at the locations listed above in

ADDRESSES

. We are holding the public hearings to provide interested parties an opportunity to present verbal testimony (formal, oral comments) or written comments regarding the proposed rule and its supporting documents. A formal public hearing is not, however, an opportunity for dialogue with the Service; it is only a forum for accepting formal verbal testimony. In contrast to the public hearings, the public informational meetings allow the public the opportunity to interact with Service staff, who will be available to provide information and address questions on the proposed rule and its supporting documents.

We cannot accept verbal testimony at any of the public informational meetings; verbal testimony can only be accepted at the public hearings. Anyone wishing to make an oral statement at a public hearing for the record is encouraged to provide a written copy of their statement to us at the hearing. In the event there is a large attendance, the time allotted for oral statements may be limited. Speakers can sign up at a hearing if they desire to make an oral statement. Oral and written statements receive equal consideration. There are no limits on the length of written comments submitted to us.

Persons with disabilities needing reasonable accommodations to participate in a public informational meeting or public hearing should contact the person listed under

FOR FURTHER INFORMATION CONTACT

. Reasonable accommodation requests should be received at least 3 business days prior to the public informational meeting or public hearing to help ensure availability; American Sign Language or English as a second language interpreter needs should be received at least 2 weeks prior to the public informational meeting or public hearing.

Taxonomy and Species Description

Grizzly bears (

Ursus arctos horribilis

) are a member of the brown bear species (

U. arctos

) that occurs in North America, Europe, and Asia; the subspecies

U. a. horribilis

is limited to North America (Rausch 1963, p. 43; Servheen 1999, pp. 50-53).

Grizzly bears are generally larger than other bears and average 200 to 300 kilograms (kg) (400 to 600 pounds (lb)) for males and 110 to 160 kg (250 to 350 lb) for females in the lower 48 States (Craighead and Mitchell 1982, pp. 517-520; Schwartz

et al.

2003

b

, p. 558). Although their coloration can vary widely from light brown to nearly black (LeFranc

et al.

1987, pp. 17-18), they can be distinguished from black bears by longer, curved claws, humped shoulders, and a face that appears to be concave (Craighead and Mitchell 1982, p. 517). Grizzly bears are long-lived mammals, generally living to be around 25 years old (LeFranc

et al.

1987, pp. 47, 51).

Behavior and Life History

Adult grizzly bears are normally solitary except when females have dependent young (Nowak and Paradiso 1983, p. 971), but they are not territorial and home ranges of adult bears

frequently overlap (Schwartz

et al.

2003

b

, pp. 565-566). Home range size is affected by resource availability, sex, age, and reproductive status (LeFranc

et al.

1987, p. 31; Blanchard and Knight 1991, pp. 48-51; Mace and Waller 1997, p. 48). Generally, females with cubs-of-the-year or yearlings have the smallest home range sizes (Aune and Kasworm 1989; Blanchard and Knight 1991, pp. 48-49; Mace and Roberts 2011, pp. 27-28). The annual home ranges of adult male grizzly bears in the GYE are approximately 800 square kilometers (sq km) (309 square miles (sq mi)), while female ranges are typically smaller, approximately 210 sq km (81 sq mi) (Bjornlie

et al.

2014, p. 3). The large home ranges of grizzly bears, particularly males, enhance maintenance of genetic diversity in the population by enabling males to mate with numerous females (Blanchard and Knight 1991, pp. 46-51; Craighead

et al.

1998, p. 326).

Young, female grizzly bears establish home ranges within or overlapping their mother's (Waser and Jones 1983, p. 361; Schwartz

et al.

2003

b,

p. 566). This pattern of home range establishment can make dispersal of females across landscapes a slow process. Radio-telemetry and genetic data suggest females establish home ranges an average of 9.8 to 14.3 km (6.1 to 8.9 mi) away from the center of their mother's home range, whereas males generally disperse farther, establishing home ranges roughly 29.9 to 42.0 km (18.6 to 26.0 mi) away from the center of their mother's (McLellan and Hovey 2001, p. 842; Proctor

et al.

2004, p. 1108).

Grizzly bears have a promiscuous mating system (Hornocker 1962, p. 70; Craighead and Mitchell 1982, p. 522; Schwartz

et al.

2003

b,

p. 563). Mating occurs from May through July with a peak in mid-June (Craighead and Mitchell 1982, p. 522; Nowak and Paradiso 1983, p. 971). Although females mate in spring and early summer, their fertilized embryos do not implant into the uterus for further development until late fall. Fat stores obtained by female grizzly bears at the end of fall are positively correlated with earlier birth dates and quicker growth rates of their cubs (Robbins

et al.

2012, p. 543). Additionally, a body fat threshold may exist below which females may not produce cubs, even when bred (Robbins

et al.

2012, p. 543). Female grizzly bears nurse cubs for 3 to 4 months inside the den. Age of first reproduction and litter size may be related to nutritional state (Stringham 1990, p. 433; McLellan 1994, p. 20; Hilderbrand

et al.

1999, pp. 135-136). Average age of first reproduction in the GYE is approximately 6 years old but can vary from 3 to 8 years of age (Schwartz

et al.

2003

b,

p. 563; Schwartz

et al.

2006

b,

p. 19). Litter size in the GYE ranges from 1 to 4 cubs (Schwartz

et al.

2003

b,

p. 563) with a mean litter size of 2.04 cubs during 1983-2001 and 2.12 cubs during 2002-2011 (Schwartz

et al.

2006

b,

p. 19; IGBST 2012, p. 34). Cubs are born in the den in late January or early February and remain with the female for 1.5 to 2.5 years, making the average time between litters in the GYE (

i.e.,

the interbirth interval) 2.78 years (Schwartz

et al.

2003

b,

p. 564; Schwartz

et al.

2006

b,

p. 20). Grizzly bears have one of the slowest reproductive rates among terrestrial mammals, resulting primarily from the reproductive factors described above: Late age of first reproduction, small average litter size, and the long interval between litters (Nowak and Paradiso 1983, p. 971; Schwartz

et al.

2003

b,

p. 564). Given the above factors, it may take a female grizzly bear 10 or more years to replace herself in a population (U.S. Fish and Wildlife Service 1993, p. 4). Grizzly bear females cease reproducing some time in their mid-to-late 20s (Schwartz

et al.

2003

a,

pp. 109-110).

Grizzly bears usually dig dens on steep slopes where wind and topography cause an accumulation of deep snow and where the snow is unlikely to melt during warm periods. Grizzly bears in the lower 48 States occupy dens for 4 to 6 months each year, beginning in October or November (Linnell

et al.

2000, p. 401; Haroldson

et al.

2002, p. 29). Most dens are located above 2,500 m (>8,000 ft) in elevation (Haroldson

et al.

2002, p. 33) and on slopes ranging from 30 to 60 degrees (Judd

et al.

1986, p. 115). Approximately 66 percent (1,684,220 acres (ac); 6,815 sq km) of the GYE is potential denning habitat, and it is well distributed, so its availability is not considered a limiting factor for grizzly bears in the GYE (Podruzny

et al.

2002, p. 22). Denning increases survival during periods of low food availability, deep snow, and low air temperature (Craighead and Craighead 1972, pp. 33-34). During this period, bears do not eat, drink, urinate, or defecate (Folk

et al.

1976, pp. 376-377; Nelson 1980, p. 2955). Hibernating grizzly bears exhibit a marked decline in heart and respiration rate, but only a slight drop in body temperature (Nowak and Paradiso 1983, p. 971). Due to their relatively constant body temperature in the den, hibernating grizzly bears may be easily aroused and have been known to exit or relocate dens when disturbed by seismic or mining activity (Harding and Nagy 1980, p. 278) or other human activities (Swenson

et al.

1997, p. 37). Dens are rarely used twice by an individual, although the same general area may be used multiple times (Schoen

et al.

1987, p. 300; Miller 1990, p. 285; Linnell

et al.

2000, p. 403). Females display stronger area fidelity than males and generally stay in their dens longer, depending on reproductive status (Judd

et al.

1986, pp. 113-114; Schoen

et al.

1987, p. 300; Miller 1990, p. 283; Linnell

et al.

2000, p. 403). In the GYE, females with new cubs typically emerge from their dens from early April to early May (Haroldson

et al.

2002, p. 29).

In preparation for hibernation, bears increase their food intake dramatically during a stage called hyperphagia (Craighead and Mitchell 1982, p. 544). Hyperphagia occurs throughout the 2 to 4 months prior to den entry (

i.e.,

August through November). During hyperphagia, excess food is converted into fat, and grizzly bears may gain as much as 1.65 kg/day (3.64 lb/day) (Craighead and Mitchell 1982, p. 544). Grizzly bears must consume foods rich in protein and carbohydrates in order to build up fat reserves to survive denning and post denning periods (Rode and Robbins 2000, pp. 1643-1644). Fat stores are crucial to the hibernating bear as they provide a source of energy and insulate the bear from cold temperatures, and are equally important in providing energy to the bear upon emergence from the den when food is still sparse relative to metabolic requirements (Craighead and Mitchell 1982, p. 544).

Nutritional Ecology

The GYE is a highly diverse landscape containing a wide array of habitat types and bear foods. Plant communities vary from grasslands at lower elevations (<1,900 m (6,230 ft)) to conifer forests at mid-elevations and subalpine and alpine meadows at higher elevations (>2,400 m (7,870 ft)). Grizzly bears are extremely omnivorous, display great diet plasticity—even within a population (Edwards

et al.

2011, pp. 883-886)—and shift and switch food habits according to their availability (Servheen 1983, pp. 1029-1030; Mace and Jonkel 1986, p. 108; LeFranc

et al.

1987, pp. 113-114; Aune and Kasworm 1989, pp. 63-71; Schwartz

et al.

2003

b,

pp. 568-569; Gunther

et al.

2014, p. 65). Gunther

et al.

(2014, p. 65) conducted an extensive literature review and documented over 260 species of foods consumed by grizzly bears in the GYE, representing 4 of the 5 kingdoms of life. The ability to use whatever food resources are available is one reason

grizzly bears are the most widely distributed bear species in the world, occupying habitats from deserts to alpine mountains and everything in between. This ability to live in a variety of habitats and eat a wide array of foods makes grizzly bears a generalist species. In contrast, specialist species eat only a few specific foods or live in only one or two specific habitat types (Krebs 2009, p. 100).

Grizzly bear diets are highly variable among individuals, seasons, and years (Servheen 1983, pp. 1029-1030; Mattson

et al.

1991

a,

pp. 1625-1626; LeFranc

et al.

1987, pp. 113-114; Felicetti

et al.

2003, p. 767; Schwartz

et al.

2003

b,

pp. 568-569; Felicetti

et al.

2004, p. 499; Fortin

et al.

2013, p. 278; Costello

et al.

2014, p. 2013; Gunther

et al.

2014, p. 65). They opportunistically seek and consume whatever plant and animal foods are available to them. Grizzly bears are always sampling new foods so that they have alternative options in years when preferred foods are scarce (Mattson

et al.

1991

a,

p. 1625). In the GYE, Blanchard and Knight (1991, p. 61) noted that, “After 10 years of food habits data collection, new feeding strategies continued to appear annually in this population.” Grizzly bears in the GYE commonly consume ungulates (bison (

Bison bison

), elk (

Cervus canadensis

), moose (

Alces alces

), and deer (

Odocoileus

species)), cutthroat trout (

Oncorhynchus clarki

), roots and tubers, army cutworm moths (

Euxoa auxiliaris

), grasses, and whitebark pine seeds (

Pinus albicaulis

) (Schwartz

et al.

2003

b,

p. 568). Bears make seasonal movements within their home ranges to locations where these foods are abundant (

e.g.,

ungulate winter ranges, calving areas, spawning streams, talus slopes) (Costello

et al.

2014, p. 2013). These foods are subject to seasonal and annual variation in availability and therefore are not abundant or available during all seasons or every year (Craighead

et al.

1995, p. 265; Gunther

et al.

2014, pp. 64-65). When high-calorie foods are not readily available, grizzly bears supplement their diet with items of lower caloric value that tend to be widely distributed across the landscape and readily available most years (Gunther

et al.

2014, p. 66). These widely distributed and abundant foods include a wide variety of plants (grasses, sedges, horsetail, and forbs), colonial insects (ants and wasps), fungi (false-truffles), berries (huckleberry, whortleberry, and gooseberry), and small mammals (voles, ground squirrels, and pocket gophers). Spatial and temporal abundance and annual predictability of these foods compensates for their lower caloric value, and, consequently, these foods can comprise a large proportion of grizzly bear annual diets (Craighead

et al.

1995, p. 253; Gunther

et al.

2014, p. 66). Grizzly bears also supplement their diet with many foods consumed opportunistically. Some opportunistic foods are consumed for only a short period each year (

e.g.,

earthworms in meadows during spring snowmelt), others are available only in small localized areas (

e.g.,

pondweed rhizomes from small ephemeral ponds within the Yellowstone caldera), and others are available only during sporadic periods of abundance (

e.g.,

midges). Many opportunistic foods are eaten during periods with shortages of more preferred foods or when randomly encountered while foraging for other species (Gunther

et al.

2014, p. 66).

Due to their high fat content, whitebark pine seeds can be an important fall food for bears in the GYE when they are available (Mattson and Jonkel 1990, p. 223; Mattson

et al.

1991

a,

p. 1623). Bears that have whitebark pine in their home range may feed predominantly on whitebark pine seeds when production exceeds 20 cones per tree (Blanchard 1990, p. 362). Whitebark pine seed availability can influence the reproductive and survival rates of these grizzly bears on an annual basis because of an increased potential for human-caused mortality during years of low whitebark pine availability (Haroldson

et al.

2006, p. 36; Schwartz

et al.

2006

b,

pp. 22, 36; IGBST 2013, p. 24). However, there has been no correlation between long-term survival of independent bears with a decline in whitebark pine availability (van Manen

et al.

2015, p. 11). Nearly one third of grizzly bear home ranges in the GYE do not contain any whitebark pine (Costello

et al.

2014, p. 2013). Bears in these areas consume other foods even during years of good whitebark pine production.

Habitat Management

Grizzly bears use a variety of habitats in the GYE (LeFranc

et al.

1987, p. 120). In general, a grizzly bear's individual habitat needs and daily movements are largely driven by the search for food, mates, cover, security, or den sites. The available habitat for bears is also influenced by people and their activities. Human activities are the primary factor impacting habitat security and the ability of bears to find and access foods, mates, cover, and den sites. Other factors influencing habitat use and function for grizzly bears include overall habitat productivity (

e.g.,

food distribution and abundance), the availability of habitat components (

e.g.,

denning areas, cover types), grizzly bear social dynamics, learned behavior and preferences of individual grizzly bears, grizzly bear population density, and random variation.

The GYE is part of the Middle Rockies ecoregion (Omernik 1987, pp. 120-121; Woods

et al.

1999, entire; McGrath

et al.

2002, entire; Chapman

et al.

2004, entire) and provides the habitat heterogeneity necessary for adequate food, denning, and cover resources. Because there are limited opportunities to increase or control these habitat components, the objective for grizzly bear habitat management is to reduce or mitigate the risk of human-caused mortality. The most effective habitat management tool for reducing grizzly bear mortality risk is managing motorized access to ensure bears have secure areas away from humans (Nielsen

et al.

2006, p. 225; Schwartz

et al.

2010, p. 661). We define secure habitat as areas more than 500 m (1,650 ft) from a motorized access route and greater than or equal to 4 hectares (ha) (10 acres (ac)) in size (U.S. Fish and Wildlife Service 2016,

Chapter 3

)). Unmanaged motorized access: (1) Increases human interaction and potential grizzly bear mortality risk; (2) increases displacement from important habitat; (3) increases habituation to humans; and (4) decreases habitat where energetic requirements can be met with limited disturbance from humans (Mattson

et al.

1987, pp. 269-271; McLellan and Shackleton 1988, pp. 458-459; McLellan 1989, pp. 1862-1864; Mace

et al.

1996, pp. 1402-1403; Schwartz

et al.

2010, p. 661). Managing motorized access helps ameliorate these impacts. Other habitat management tools that minimize displacement and reduce grizzly bear mortality risk include regulating livestock allotments and developed sites on public lands. Implementing food storage orders on public lands also reduces mortality risk for both humans and grizzly bears. Requiring users and recreationists in grizzly bear habitat to store their food, garbage, and other bear attractants so that they are inaccessible to bears reduces encounters and grizzly bear-human conflicts.

The primary factor affecting grizzly bears at both the individual and population level is excessive human-caused mortality. Regulating human-caused mortality through habitat management is an effective approach, as evidenced by increasing grizzly bear populations in the lower 48 States where motorized access standards exist (

e.g.,

GYE and Northern Continental Divide Ecosystem). This requires

ongoing monitoring of the grizzly bear population to understand if it is sufficiently resilient to allow for a conservative level of human-caused mortality without causing population decline.

Population Ecology—Background

The scientific discipline that informs decisions about most wildlife population management is population ecology: the study of how populations change over time and space and interact with their environment (Vandermeer and Goldberg 2003, p. 2; Snider and Brimlow 2013, p. 1). Ultimately, the goal of population ecology is to understand why and how populations change over time. Wildlife managers and population ecologists monitor a number of factors to gauge the status of a population and make scientifically informed decisions. These measures include population size, population trend, density, and occupied range.

While population size is a well-known and easily understood metric, it only provides information about a population at a single point in time. Wildlife managers often want to know how a population is changing over time and why. Population trend is determined by births, deaths, and how many animals move into or out of the population (

i.e.,

disperse) and is typically expressed as the population growth rate (represented by the symbol λ, the Greek letter “lambda”). For grizzly bear populations, lambda estimates the average rate of annual growth, with a value of 1.0 indicating a stable population trend with no net growth or decline. A lambda value of 1.03 means the population size is increasing at 3 percent per year. Conversely, a lambda value of 0.98 means the population size is decreasing at 2 percent per year.

In its simplest form, population trend is driven by births and deaths. Survival and reproduction are the fundamental demographic vital rates driving whether the grizzly bear population increases, decreases, or remains stable. When wildlife biologists refer to demographic vital rates, they are referring to all of the different aspects of reproduction and survival that cumulatively determine a population's trend (

i.e.,

lambda). Some of the demographic factors influencing population trend for grizzly bears are age-specific survival, sex-specific survival, average number of cubs per litter, the time between litters (

i.e.,

interbirth interval), age ratios, sex ratios, average age of first reproduction, lifespan, transition probabilities (see glossary), immigration, and emigration. These data are all used to determine if and why a population is increasing or decreasing (Anderson 2002, p. 53; Mills 2007, p. 59; Mace

et al.

2012, p. 124).

No population can grow forever because the resources it requires are finite. This understanding led ecologists to develop the concept of carrying capacity (expressed as the symbol “K”). This is the maximum number of individuals a particular environment can support over the long term without resulting in population declines caused by resource depletion (Vandermeer and Goldberg 2003, p. 261; Krebs 2009, p. 148). Classical studies of population growth occurred under controlled laboratory conditions where populations of a single organism, often an insect species or single-celled organism, were allowed to grow in a confined space with a constant supply of food (Vandermeer and Goldberg 2003, pp. 14-17). Under these conditions, K is a constant value that is approached in a predictable way that can be described by a mathematical equation. However, few studies of wild populations have demonstrated the stability and constant population size suggested by this equation. Instead, many factors affect carrying capacity of animal populations in the wild, and populations usually fluctuate above and below carrying capacity, resulting in relative population stability over time (

i.e.,

lambda value of approximately 1.0 over the long term) (Colinvaux 1986, pp. 138-139, 142; Krebs 2009, p. 148). For populations at or near carrying capacity, population size fluctuates just above and below carrying capacity, sometimes resulting in annual estimates of lambda showing a declining population (figure 1). However, to obtain a biologically meaningful estimate of average annual population growth rate for a long-lived species like the grizzly bear that reproduces only once every 3 years and does not start reproducing until at least 4 years old, we must examine lambda over a longer period of time to see what the average trend is over that specified time. This is not an easy task; for grizzly bears, it takes at least 6 years of monitoring as many as 30 females with radio-collars to accurately estimate average annual population growth (Harris

et al.

2011, p. 29).

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When a population is at or near carrying capacity, mechanisms that regulate or control population size fall into two broad categories: density-dependent effects and density-independent effects. Generally, factors that limit population growth more strongly as population size increases are density-dependent effects, or intrinsic factors, usually expressed through individual behaviors, physiology, or genetic potential (McLellan 1994, p. 15). Extrinsic factors, such as drought or fire that kill individuals regardless of how many individuals are in a population, are considered density-independent effects (Colinvaux 1986, p. 172). These extrinsic factors may include changes in resources, predators, or human impacts. Population stability (

i.e.,

fluctuation around carrying capacity or a long-term equilibrium) is often influenced by a combination of density-dependent and density-independent effects. Among grizzly bears, indicators of density-dependent population regulation can include: (1) Decreased yearling and cub survival due to increases in intraspecific killing (

i.e.,

bears killing other bears), (2) decreases in home-range size, (3) increases in generation time, (4) increases in age of first reproduction, and (5) decreased reproduction (McLellan 1994, entire; Eberhardt 2002, pp. 2851-2852; Kamath

et al.

2015, p. 10; van Manen

et al.

2015, pp.8-9). Indicators that density-independent effects are influencing population growth can include: (1) Larger home-range sizes (because bears are roaming more widely in search of foods) (McLoughlin

et al.

2000, pp. 49-51), (2) decreased cub and yearling survival due to starvation, (3) increases in age of first reproduction due to limited food resources, and (4) decreased reproduction due to limited food resources. As a result of these sometimes similar indicators, determining whether a population is affected more strongly by density-dependent or density-independent effects can be a complex undertaking. For long-lived mammals such as grizzly bears, extensive data collected over decades are needed to understand if and how these factors are operating in a population. We have these data for the GYE grizzly bear population, and the IGBST has been able to tease apart some of these confounding effects to find that density-dependent effects are the likely cause of the recent slow in population growth (see

Changes in Food Resources

under Factor E, below, for more detailed information).

Population viability analyses (PVAs) are another tool population ecologists often use to assess the status of a population by estimating its likelihood of persistence in the future. Boyce

et al.

(2001, pp. 1-11) reviewed the existing published PVAs for GYE grizzly bears and updated these previous analyses using data collected since the original analyses were completed. They also conducted new PVAs using two software packages that had not been available to previous investigators. They found that the GYE grizzly bear population had a 1 percent chance of

going extinct within the next 100 years and a 4 percent chance of going extinct in the next 500 years (Boyce

et al.

2001, pp. 1, 10-11). The authors cautioned that their analyses were not entirely sufficient because they were not able to consider possible changes in habitat and how these may affect population vital rates (Boyce

et al.

2001, pp. 31-32). Based on this recommendation, Boyce worked with other researchers to develop a habitat-based framework for evaluating mortality risk of a grizzly bear population in Alberta, Canada (Nielsen

et al.

2006, p. 225). They concluded that secure habitat (low mortality risk) was the key to grizzly bear survival. Schwartz

et al.

(2010, p. 661) created a similar mortality risk model for the GYE with similar results. Both studies suggest that managing for secure habitat is one of the most effective management actions to ensure population persistence.

Recovery Planning and Implementation

Background

Prior to the arrival of Europeans, the grizzly bear occurred throughout the western half of the contiguous United States, central Mexico, western Canada, and most of Alaska (Roosevelt 1907, pp. 27-28; Wright 1909, pp. vii, 3, 185-186; Merriam 1922, p. 1; Storer and Tevis 1955, p. 18; Rausch 1963, p. 35; Herrero 1972, pp. 224-227; Schwartz

et al. 2003b,

pp. 557-558). Pre-settlement population levels for the western contiguous United States are believed to have been in the range of 50,000 animals (Servheen 1999, p. 50). With European settlement of the American West and government-funded bounty programs aimed at eradication, grizzly bears were shot, poisoned, and trapped wherever they were found, and the resulting range and population declines were dramatic (Roosevelt 1907, pp. 27-28; Wright 1909, p. vii; Storer and Tevis 1955, pp. 26-27; Leopold 1967, p. 30; Koford 1969, p. 95; Craighead and Mitchell 1982, p. 516; Servheen 1999, pp. 50-51). The range and numbers of grizzly bears were reduced to less than 2 percent of their former range and numbers by the 1930s, approximately 125 years after first contact (U.S. Fish and Wildlife Service 1993, p. 9; Servheen 1999, p. 51). Of 37 grizzly bear populations present within the lower 48 States in 1922, 31 were extirpated by 1975 (Servheen 1999, p. 51).

By the 1950s, with little or no conservation effort or management directed at maintaining grizzly bears anywhere in their range, the GYE population had been reduced in numbers and was restricted largely to the confines of Yellowstone National Park and some surrounding areas (Craighead

et al.

1995, pp. 41-42; Schwartz

et al.

2003

b,

pp. 575-579). High grizzly bear mortality in 1970 and 1971, following closure of the open-pit garbage dumps in Yellowstone National Park (Gunther 1994, p. 550; Craighead

et al.

1995, pp. 34-36), and concern about grizzly bear population status throughout its remaining range prompted the 1975 listing of the grizzly bear as a threatened species in the lower 48 States under the Act (40 FR 31734; July 28, 1975). When the grizzly bear was listed in 1975, the population estimate in the GYE ranged from 136 to 312 individuals (Cowan

et al.

1974, pp. 32, 36; Craighead

et al.

1974, p. 16; McCullough 1981, p. 175).

Grizzly bear recovery has required, and will continue to require, cooperation among numerous government agencies and the public for a unified management approach. To this end, there are three interagency groups that help guide grizzly bear management in the GYE. The Interagency Grizzly Bear Study Team (IGBST), created in 1973, provides the scientific information necessary to make informed management decisions about grizzly bear habitat and conservation in the GYE. Since its formation in 1973, the published work of the IGBST has made the GYE grizzly bear population the most studied in the world. The wealth of biological information produced by the IGBST over the years includes 30 annual reports, hundreds of articles in peer-reviewed journals, dozens of theses, and other technical reports (see:

http://www.nrmsc.usgs.gov/science/igbst/detailedpubs

). Members of the IGBST include scientists and wildlife managers from the Service, U.S. Geological Survey, National Park Service, Forest Service, academia, and each State wildlife agency involved in grizzly bear recovery.

The second interagency group guiding grizzly bear conservation efforts is the Interagency Grizzly Bear Committee (hereafter referred to as the IGBC). Created in 1983, its members coordinate management efforts and research actions across multiple Federal lands and States to recover the grizzly bear in the lower 48 States (USDA and USDOI 1983, entire). The objective of the IGBC is to change land management practices to more effectively provide security and maintain or improve habitat conditions for the grizzly bear (USDA and USDOI 1983, entire). IGBC members include upper level managers from all affected State and Federal agencies (USDA and USDOI 1983, entire).

The third interagency group guiding management of the GYE grizzly bear population is a subcommittee of the IGBC: The Yellowstone Ecosystem Subcommittee. Formed in 1983 to coordinate recovery efforts specific to the GYE, the Yellowstone Ecosystem Subcommittee includes mid-level managers and representatives from the Service; the five GYE National Forests (the Shoshone, Beaverhead-Deerlodge, Bridger-Teton, Custer-Gallatin, and Caribou-Targhee); Yellowstone National Park; Grand Teton National Park; the Wyoming Game and Fish Department (WGFD); the Montana Department of Fish, Wildlife, and Parks (MTFWP); the Idaho Department of Fish and Game (IDFG); the Bureau of Land Management (BLM); county governments from each affected State; the Northern Arapahoe Tribe; and the Eastern Shoshone Tribe (USDA and USDOI 1983). The IGBST is an advisor to the subcommittee providing all the scientific information on the GYE grizzly bear population and its habitat.

Recovery Planning

In accordance with section 4(f)(1) of the Act, the Service completed a Grizzly Bear Recovery Plan (Recovery Plan) in 1982 (U.S. Fish and Wildlife Service 1982, p. ii). Recovery plans serve as road maps for species recovery—they lay out where we need to go and how to get there through specific actions. Recovery plans are not regulatory documents and are instead intended to provide guidance to the Service, States, and other partners on methods of minimizing threats to listed species and on criteria that may be used to determine when recovery is achieved.

The Recovery Plan identified six recovery ecosystems within the conterminous United States thought to support grizzly bears. Today, grizzly bear distribution is primarily within and around the areas identified as Recovery Zones (U.S. Fish and Wildlife Service 1993, pp. 10-13, 17-18), including: (1) The GYE in northwest Wyoming, eastern Idaho, and southwest Montana (24,000 sq km (9,200 sq mi)) at more than 700 bears (Haroldson

et al.

2014, p. 17); (2) the Northern Continental Divide Ecosystem (NCDE) of north-central Montana (25,000 sq km (9,600 sq mi)) at more than 900 bears (Kendall

et al.

2009, p. 9; Mace

et al.

2012, p. 124); (3) the North Cascades area of north-central Washington (25,000 sq km (9,500 sq mi)) at fewer than 20 bears (last documented sighting in 1996) (Almack

et al.

1993, p. 4; National Park Service and U.S. Fish and Wildlife Service 2015, p. 3); (4) the Selkirk Mountains area of north Idaho, northeast

Washington, and southeast British Columbia (5,700 sq km (2,200 sq mi)) at approximately 88 bears (U.S. Fish and Wildlife Service 2011, p. 26); and (5) the Cabinet-Yaak area of northwest Montana and northern Idaho (6,700 sq km (2,600 sq mi)) at approximately 48 bears (Kendall

et al.

2015, p. 1). The Bitterroot Recovery Zone in the Bitterroot Mountains of central Idaho and western Montana (14,500 sq km (5,600 sq mi)) is not known to contain a population of grizzly bears at this time (U.S. Fish and Wildlife Service 1996, p. 1; 65 FR 69624, November 17, 2000; U.S. Fish and Wildlife Service 2000, p. 1-3). The San Juan Mountains of Colorado also were identified as an area of possible grizzly bear occurrence (40 FR 31734, July 28, 1975; U.S. Fish and Wildlife Service 1982, p. 12; U.S. Fish and Wildlife Service 1993, p. 11), but no confirmed sightings of grizzly bears have occurred there since a grizzly bear mortality in 1979 (U.S. Fish and Wildlife Service 1993, p. 11).

In 1993, the Service completed revisions to the Recovery Plan to include additional tasks and new information that increased the focus and effectiveness of recovery efforts (U.S. Fish and Wildlife Service 1993, pp. 41-58). In 1996 and 1997, we released supplemental chapters to the Recovery Plan to direct recovery in the Bitterroot and North Cascades Recovery Zones, respectively (U.S. Fish and Wildlife Service 1996; U.S. Fish and Wildlife Service 1997). In the GYE, we updated both the habitat and demographic recovery criteria in 2007 (72 FR 11376, March 13, 2007). We proposed revisions to the demographic recovery criteria in 2013 (78 FR 17708, March 22, 2013) and are proposing additional revisions concurrent with this proposed rule to reflect the best available science. Below, we report the status of both the habitat and demographic recovery criteria in the GYE.

In 1979, the IGBST developed the first comprehensive “Guidelines for Management Involving Grizzly Bears in the Greater Yellowstone Area” (hereafter referred to as the Guidelines) (Mealey 1979, pp. 1-4). We determined in a biological opinion that implementation of the Guidelines by Federal land management agencies would promote conservation of the grizzly bear (U.S. Fish and Wildlife Service 1979, p. 1). Beginning in 1979, the five affected National Forests (Beaverhead-Deerlodge, Bridger-Teton, Caribou-Targhee, Custer-Gallatin, and Shoshone), Yellowstone and Grand Teton National Parks, and the BLM in the GYE began managing habitats for grizzly bears under direction specified in the Guidelines.

In 1986, the IGBC modified the Guidelines to more effectively manage habitat by mapping and managing according to three different management situations (USDA Forest Service 1986, pp. 35-39). In areas governed by “Management Situation One,” grizzly bear habitat maintenance and improvement and grizzly bear-human conflict minimization received the highest management priority. In areas governed by “Management Situation Two,” grizzly bear use was important, but not the primary use of the area. In areas governed by “Management Situation Three,” grizzly bear habitat maintenance and improvement were not management considerations.

The National Forests and National Parks delineated 18 different bear management units (BMUs) within the GYE Recovery Zone to aid in managing habitat and monitoring population trends. Each BMU was further subdivided into subunits, resulting in a total of 40 subunits contained within the 18 BMUs (see map at

http://www.fws.gov/mountain-prairie/es/species/mammals/grizzly/Yellowstone_Recovery_Zone_map.pdf

). The BMUs are analysis areas that approximate the lifetime size of a female's home range, while subunits are analysis areas that approximate the annual home range size of adult females. Subunits provide the optimal scale for evaluation of seasonal feeding opportunities and landscape patterns of food availability for grizzly bears (Weaver

et al.

1986, p. 236). The BMUs and subunits were identified to provide enough quality habitat and to ensure that grizzly bears were well distributed across the GYE Recovery Zone as per the Recovery Plan (U.S. Fish and Wildlife Service 2007

c,

pp. 20, 41, 44-46). Management improvements made as a result of these Guidelines are discussed under Factor A, below.

Habitat-Based Recovery Criteria

On June 17, 1997, we held a public workshop in Bozeman, Montana, to develop and refine habitat-based recovery criteria for the grizzly bear, with an emphasis on the GYE. This workshop was held as part of the settlement agreement in

Fund for Animals

v.

Babbitt,

967 F.Supp.6 (D. DC 1997). A

Federal Register

notice notified the public of this workshop and provided interested parties an opportunity to participate and submit comments (62 FR 19777; April 23, 1997). After considering 1,167 written comments, we developed biologically-based habitat recovery criteria with the overall goal of maintaining or improving habitat conditions at levels that existed in 1998.

There is no published method to deductively calculate minimum habitat values required for a healthy and recovered population. Grizzly bears are long-lived opportunistic omnivores whose food and space requirements vary depending on a multitude of environmental and behavioral factors and on variation in the experience and knowledge of each individual bear. Grizzly bear home ranges overlap and change seasonally, annually, and with reproductive status. While these factors make the development of threshold habitat criteria difficult, habitat criteria may be established by assessing what habitat factors in the past were compatible with a stable to increasing grizzly bear population, and then using these habitat conditions as threshold values to be maintained to ensure a healthy population (

i.e.,

a “no net loss” approach), as suggested by Nielsen

et al.

(2006, p. 227). We selected 1998 levels as our baseline year because it was known that habitat values at this time were compatible with an increasing grizzly bear population throughout the 1990s (Eberhardt

et al.

1994, p. 362; Knight and Blanchard 1995, pp. 5, 9; Knight

et al.

1995, p. 247; Boyce

et al.

2001, pp. 10-11; Schwartz

et al.

2006

b,

p. 48) and that the levels of both secure habitat and the number and capacity of developed sites had changed little from 1988 to 1998 (USDA Forest Service 2004, pp. 140-141, 159-162). The 1998 baseline is also described in detail in Factor A, below.

The habitat-based recovery criteria established objective, measurable values for levels of motorized access, secure habitat, developed sites, and livestock allotments (

i.e.,

“the 1998 baseline”) for the GYE. The 1998 values will not change through time, unless improvements benefit bears. As each of these management objectives are central to potential present or threatened destruction, modification, or curtailment of habitat or range, each of these criteria are discussed in detail under Factor A, below. These habitat-based recovery criteria have been met since their incorporation into the Recovery Plan (U.S. Fish and Wildlife Service 2007

b,

entire).

Additionally, we developed several monitoring items that may help inform management decisions or explain population trends: (1) Trends in the location and availability of whitebark pine, cutthroat trout, army cutworm moths, and winter-killed ungulate carcasses; and (2) grizzly bear mortality numbers, locations, and causes; grizzly bear-human conflicts; nuisance bear

management actions; bear-hunter conflicts; and bear-livestock conflicts (U.S. Fish and Wildlife Service 2007

c,

pp. 25-60). Federal and State agencies monitor these items, and the IGBST produces an annual report with their results. This information is used to examine relationships between food availability, human activity, and demographic parameters of the population such as survival, population growth, or reproduction. The current habitat-based recovery criteria have been appended to the Recovery Plan and are included in the draft 2016 Conservation Strategy, which is the comprehensive post-delisting management plan for a recovered population as called for in the Recovery Plan.

Suitable Habitat

Because we used easily recognized boundaries to delineate the boundaries of the proposed GYE grizzly bear DPS, it includes both suitable and unsuitable habitat (figure 2). For the purposes of this proposed rule, “suitable habitat” is considered the area within the DPS boundaries capable of supporting grizzly bear reproduction and survival now and in the foreseeable future. We have defined “suitable habitat” for grizzly bears as areas having three characteristics: (1) Being of adequate habitat quality and quantity to support grizzly bear reproduction and survival; (2) being contiguous with the current distribution of GYE grizzly bears such that natural recolonization is possible; and (3) having low mortality risk as indicated through reasonable and manageable levels of grizzly bear mortality.

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Our definition and delineation of suitable habitat is built on the widely accepted conclusions of extensive research (Craighead 1980, pp. 8-11; Knight 1980, pp. 1-3; Peek

et al.

1987, pp. 160-161; Merrill

et al.

1999, pp. 233-235; Schwartz

et al.

2010, p. 661) that grizzly bear reproduction and survival is a function of both the biological needs of grizzly bears and remoteness from human activities, which minimizes mortality risk for grizzly bears. Mountainous areas provide hiding cover, the topographic variation necessary to ensure a wide

variety of seasonal foods, and the steep slopes used for denning (Judd

et al.

1986, pp. 114-115; Aune and Kasworm 1989, pp. 29-58; Linnell

et al.

2000, pp. 403-405). Higher elevation, mountainous regions in the GYE (Omernik 1987, pp. 118-125; Omernik 1995, pp. 49-62; Woods

et al.

1999, entire; McGrath

et al.

2002, entire; Chapman

et al.

2004, entire) contain high-energy foods such as whitebark pine seeds (Mattson and Jonkel 1990, p. 223; Mattson

et al.

1991

a,

p. 1623) and army cutworm moths (Mattson

et al.

1991

b,

2434; French

et al.

1994, p. 391).

For our analysis of suitable habitat, we considered the Middle Rockies ecoregion, within which the GYE is contained (Omernik 1987, pp. 120-121; Woods

et al.

1999, entire; McGrath

et al.

2002, entire; Chapman

et al.

2004, entire) to meet grizzly bear biological needs providing food, seasonal foraging opportunities, cover, and denning areas (Mattson and Merrill 2002, p. 1125). Although grizzly bears historically occurred throughout the area of the proposed GYE grizzly bear DPS (Stebler 1972, pp. 297-298), many of these habitats are not, today, biologically suitable for grizzly bears. While there are records of grizzly bears in eastern Wyoming near present-day Sheridan, Casper, and Wheatland, even in the early 19th century, indirect evidence suggests that grizzly bears were less common in these eastern prairie habitats than in mountainous areas to the west (Rollins 1935, p. 191; Wade 1947, p. 444). Grizzly bear presence in these drier, grassland habitats was associated with rivers and streams where grizzly bears used bison carcasses as a major food source (Burroughs 1961, pp. 57-60; Herrero 1972, pp. 224-227; Stebler 1972, pp. 297-298; Mattson and Merrill 2002, pp. 1128-1129). Most of the short-grass prairie on the east side of the Rocky Mountains has been converted into agricultural land (Woods

et al.

1999, entire), and high densities of traditional food sources are no longer available due to land conversion and human occupancy of urban and rural lands. Traditional food sources such as bison and elk have been dramatically reduced and replaced with domestic livestock attractants such as cattle, sheep, chickens, goats, pigs, and bee hives, which can become anthropogenic sources of prey for grizzly bears. While food sources such as grasses and berries are abundant in some years in the riparian zones within which the bears travel, these are not reliable every year and can only support a small number of bears. These nutritional constraints and the potential for human-bear conflicts limit the potential for a self-sustaining population of grizzly bears to develop in the prairies, although we expect some grizzly bears to live in these areas. Because wild bison herds no longer exist in these areas, they are no longer capable of contributing in a meaningful way to the overall status of the GYE grizzly bear DPS. Thus, we did not include drier sagebrush, prairie, or agricultural lands within our definition of suitable habitat because these land types no longer contain adequate food resources (

i.e.,

bison) to support grizzly bears. Figure 2, above, illustrates suitable habitat within the GYE grizzly bear DPS.

Human-caused mortality risk also can impact which habitat might be considered suitable. Some human-caused mortality is unavoidable in a dynamic system where hundreds of bears inhabit large areas of diverse habitat with several million human visitors and residents. The negative impacts of humans on grizzly bear survival and habitat use are well documented (Harding and Nagy 1980, p. 278; McLellan and Shackleton 1988, pp. 458-459; Aune and Kasworm 1989, pp. 83-103; McLellan 1989, pp. 1862-1864; McLellan and Shackleton 1989, pp. 377-378; Mattson 1990, pp. 41-44; Mattson and Knight 1991, pp. 9-11; Mace

et al.

1996, p. 1403; McLellan

et al.

1999, pp. 914-916; White

et al.

1999, p. 150; Woodroffe 2000, pp. 166-168; Boyce

et al.

2001, p. 34; Johnson

et al.

2004, p. 976; Schwartz

et al.

2010, p. 661). These effects range from temporary displacement to actual mortality. Grizzly bear persistence in the contiguous United States between 1920 and 2000 was negatively associated with human and livestock densities (Mattson and Merrill 2002, pp. 1129-1134). As human population densities increase, the frequency of encounters between humans and grizzly bears also increases, resulting in more human-caused grizzly bear mortalities due to a perceived or real threat to human life or property (Mattson

et al.

1996, pp. 1014-1015). Similarly, as livestock densities increase in habitat occupied by grizzly bears, depredations follow. Although grizzly bears frequently coexist with cattle without depredating them, when grizzly bears encounter domestic sheep, they usually are attracted to such flocks and depredate the sheep (Jonkel 1980, p. 12; Knight and Judd 1983, pp. 188-189; Orme and Williams 1986, pp. 199-202; Anderson

et al.

2002, pp. 252-253). If repeated depredations occur, managers either relocate the bear or remove it from the population, resulting in such domestic sheep areas becoming population sinks (Knight

et al.

1988, pp. 122-123).

Because urban sites and sheep allotments possess high mortality risks for grizzly bears, we did not include these areas as suitable habitat (Knight

et al.

1988, pp. 122-123). Based on 2000 census data, we defined urban areas as census blocks with human population densities of more than 50 people per sq km (129 people per sq mi) (U.S. Census Bureau 2005, entire). Cities within the Middle Rockies ecoregion, such as West Yellowstone, Gardiner, Big Sky, and Cooke City, Montana, and Jackson, Wyoming, were not included as suitable habitat. There are large, contiguous blocks of sheep allotments in peripheral areas of the ecosystem in the Wyoming Mountain Range, the Salt River Mountain Range, and portions of the Wind River Mountain Range on the Bridger-Teton and the Targhee National Forests (see figure 2, above). This spatial distribution of sheep allotments on the periphery of suitable habitat results in areas of high mortality risk to bears within these allotments and a few small, isolated patches or strips of suitable habitat adjacent to or within sheep allotments. These strips and patches of land possess higher mortality risks for grizzly bears because of their enclosure by and proximity to areas of high mortality risk. This phenomenon in which the quantity and quality of suitable habitat is diminished because of interactions with surrounding less suitable habitat is known as an “edge effect” (Lande 1988, pp. 3-4; Yahner 1988, pp. 335-337; Mills 1995, p. 396). Edge effects are exacerbated in small habitat patches with high perimeter-to-area ratios (

i.e.,

those that are longer and narrower) and in wide-ranging species such as grizzly bears because they are more likely to encounter surrounding, unsuitable habitat (Woodroffe and Ginsberg 1998, p. 2126). Due to the negative edge effects of this distribution of sheep allotments on the periphery of grizzly bear range, our analysis did not classify linear strips and isolated patches of habitat as suitable habitat.

Finally, dispersal capabilities of grizzly bears were considered in our determination of which potential habitat areas might be considered suitable. Although the Bighorn Mountains west of I-90 near Sheridan, Wyoming, are grouped within the Middle Rockies ecoregion, they are not connected to the current distribution of grizzly bears via suitable habitat or linkage zones, nor are there opportunities for such linkage. The Bighorn Mountains are comprised of 6,341 sq km (2,448 sq mi) of habitat that is classified as part of the Middle

Rockies ecoregion, but are separated from the current grizzly bear distribution by approximately 100 km (60 mi) of a mosaic of private and BLM lands primarily used for agriculture, livestock grazing, and oil and gas production (Chapman

et al.

2004, entire). Although there is a possibility that individual bears may emigrate from the GYE to the Bighorn Mountains occasionally, this dispersal distance exceeds the average dispersal distance for both males (30 to 42 km (19 to 26 mi)) and females (10 to 14 km (6 to 9 mi)) (McLellan and Hovey 2001, p. 842; Proctor

et al.

2004, p. 1108). Without constant emigrants from suitable habitat, the Bighorn Mountains will not support a self-sustaining grizzly bear population. Therefore, due to the fact that this mountain range is disjunct from other suitable habitat and current grizzly bear distribution, our analysis did not classify the Bighorn Mountains as suitable habitat within the GYE grizzly bear DPS boundaries.

Some areas that do not meet our definition of suitable habitat may still be used by grizzly bears (4,635 sq km (1,787 sq mi)) (Schwartz

et al.

2002, p. 209; Schwartz

et al.

2006

b,

pp. 64-66). The records of grizzly bears in these unsuitable habitat areas are generally due to recorded grizzly bear-human conflicts or to transient animals. These areas are defined as unsuitable due to the high risk of mortality resulting from these grizzly bear-human conflicts. These unsuitable habitat areas do not support grizzly bear reproduction or survival because bears that repeatedly come into conflict with humans or livestock are usually either relocated or removed (

i.e.,

euthanized or placed in an approved American Zoological Association facility) from these areas.

According to the habitat suitability criteria described above, the GYE contains approximately 46,035 sq km (17,774 sq mi) of suitable grizzly bear habitat within the DPS boundaries; or roughly 24 percent of the total area within the DPS boundaries (see figure 2, above). This amount of suitable habitat is sufficient to meet all habitat needs of a recovered grizzly bear population and provide ecological resiliency to the population through the availability of widely distributed, high-quality habitat that will allow the population to respond to environmental changes. Grizzly bears currently occupy about 90 percent of that suitable habitat (42,180 sq km (16,286 sq mi)) (Haroldson 2015,

in litt.

). It is important to note that the current grizzly bear occupancy does not mean that equal densities of grizzly bears are found throughout the region. Instead, most grizzly bears (approximately 75 percent of females with cubs-of-the-year) are within the PCA for most or part of each year (Schwartz

et al.

2006

a,

pp. 64-66; Haroldson 2014,

in litt.

). Grizzly bear use of suitable habitat may vary seasonally and annually with different areas being more important than others in some seasons or years (Aune and Kasworm 1989, pp. 48-62). We expect grizzly bears to naturally recolonize much, if not all, suitable habitat (Pyare

et al.

2004, pp. 5-6).

Population and Demographic Recovery Criteria

The 1993 Recovery Plan identified three demographic parameters that should be measured to assess recovery in the GYE. The first criterion established a minimum population size. The second criterion ensured reproductive females were distributed across the Recovery Zone, and the third criterion created total mortality limits that would allow the population to achieve recovery. Since the 1993 Recovery Plan was released, we have evaluated and updated how we assess those recovery criteria as newer, better science became available. These revisions include implementing new scientific methods to determine the status of the GYE grizzly bear demographic monitoring area (DMA) population, estimate population size, and determine what levels of mortality the population could withstand without causing population decline (

i.e.,

the sustainable mortality rate). The DMA is the area within which the population is annually surveyed and estimated and within which the total mortality limits apply, and is based on the suitable habitat area (see figure 2, above). The Wildlife Monograph: “Temporal, Spatial, and Environmental Influences on The Demographics of Grizzly Bears in The Greater Yellowstone Ecosystem” (Schwartz

et al.

2006

b,

entire); the report: “Reassessing Methods to Estimate Population Size and Sustainable Mortality Limits for the Yellowstone Grizzly Bear” (IGBST 2005, entire); and the report: “Reassessing Methods to Estimate Population Size and Sustainable Mortality Limits for the Yellowstone Grizzly Bear Workshop Document Supplement 19-21 June, 2006” (IGBST 2006, entire) provided the scientific basis for revising the demographic recovery criteria in the GYE in 2007 (72 FR 11376; March 13, 2007). Similarly, the revisions we proposed to implement in 2013 (78 FR 17708; March 22, 2013) are based on updated demographic analyses using the same methods as before (Schwartz

et al.

2006

b,

pp. 9-16) and reported in the IGBST's 2012 report: “Updating and Evaluating Approaches to Estimate Population Size and Sustainable Mortality Limits for Grizzly Bears in the Greater Yellowstone Ecosystem” (hereafter referred to as the 2012 IGBST report). This 2012 IGBST report informed the scientific basis for the changes we proposed to the GYE demographic recovery criteria in 2013.

In 2013, we proposed to change two of the recovery criteria for the Yellowstone Ecosystem in the Grizzly Bear Recovery Plan (78 FR 17708; March 22, 2013). Changes were proposed for the demographic goal of maintaining a minimum population of 500 animals and at least 48 females with cubs, and to eliminate this criterion's dependence on a specific counting method; and to revise the area where the population would be counted and where total mortality limits would apply. We chose to revise the criteria because they no longer represented the best scientific data or the best technique to assess recovery of the GYE grizzly bear DMA population (78 FR 17708; March 22, 2013). Specifically, these criteria warrant revision because: (1) Updated demographic analyses for 2002-2011 indicate that the rate of growth seen during the 1983-2001 period has slowed and sex ratios have changed; (2) there is consensus among scientists and statisticians that the area within which we apply total mortality limits should be the same area we use to estimate population size; and (3) the population has basically stabilized inside the DMA since 2002, with an average population size between 2002-2014 of 674 using the model-averaged Chao2 population estimation method (95% Confidence Interval (CI) = 600-747). This stabilization is evidence that the population is close to its carrying capacity as evidenced by density dependent regulation occurring inside the DMA (van Manen

et al.

2015, entire). Also, there is a need to allow the IGBST to update the method used to measure population size demographic criteria so that they can incorporate results from new scientific methods based on peer-reviewed, scientific literature as they become available.

We released these proposed revisions related to population size and total mortality limits for public comment in 2013 (78 FR 17708; March 22, 2013) but did not finalize them so that we could consider another round of public comments on these revisions in association with the comments on this proposed rule. Further proposed revisions to the Recovery Plan Supplement: Revised Demographic Criteria and the draft 2016 Conservation

Strategy for the Grizzly Bear in the GYE are being made available for public review and comment concurrent with this proposed rule. After review and incorporation of appropriate public comments, we plan to release a final Grizzly Bear Recovery Plan Supplement: Revised Demographic Criteria (U.S. Fish and Wildlife Service 1993, p. 44) and the 2016 Conservation Strategy for the Grizzly Bear in the Greater Yellowstone Ecosystem concurrent with release of a final determination on this proposed rule.

Below, we summarize relevant portions of the demographic analyses contained in the IGBST's 2012 report (IGBST 2012, entire) and compare them with the previous results of Schwartz

et al.

(2006

b,

entire) to draw conclusions concerning the grizzly bear population in the GYE DMA using these collective results. These analyses inform the scientific basis for our proposed revisions. While Schwartz

et al.

(2006

b,

p. 11) used data from 1983 through 2001; the 2012 IGBST report examined a more recent time period, 2002 through 2011 (IGBST 2012, p. 33). The IGBST found that population growth had slowed since the previous time period, but was still stable to slightly increasing, meaning the population had not declined. Because the fates of some radio-collared bears are unknown, Schwartz

et al.

(2006

b,

p. 48) and the IGBST (2012, p. 34) calculated two separate estimates of population growth rate: one based on the assumption that every bear with an unknown fate had died (

i.e.,

a conservative estimate); and the other simply removing bears with an unknown fate from the sample. The true population growth rate is assumed to be somewhere in between these two estimates because we know from 30 years of tracking grizzly bears with radio-collars that every lost collar does not indicate a dead bear. While Schwartz

et al.

(2006

b,

p. 48) found the GYE grizzly bear DMA population increased at a rate between 4.2 and 7.6 percent per year between 1983 and 2002, the IGBST (2012, p. 34) found this growth had slowed and leveled off and was between 0.3 percent and 2.2 percent per year during 2002-2011.

Schwartz

et al.

(2006

b,

p. 29) analyzed survivorship of cubs, yearlings, and independent bears based on whether they lived inside Yellowstone National Park, outside the Park but inside the Recovery Zone or PCA, or outside the PCA entirely. The PCA boundaries (containing 23,853 sq km (9,210 sq mi) correspond to those of the Yellowstone Recovery Zone (U.S. Fish and Wildlife Service 1993, p. 41) and will replace the Recovery Zone boundary (see figure 2, above). They concluded that grizzly bears were approaching carrying capacity inside Yellowstone National Park. The IGBST (2012, p. 33) documented lower cub and yearling survival than in the previous time period, results consistent with the conclusion by Schwartz

et al.

(2006

b

). Importantly, annual survival of independent females (the most influential age-sex cohort on population trend) remained the same while independent male survival increased (IGBST 2012, p. 33). Collectively, these two studies indicate that the growth rate of the GYE grizzly bear DMA population has slowed as bear densities have approached carrying capacity, particularly in the core area of occupied range.

Mortality reduction is a key part of any successful management effort for grizzly bears; however, some mortality, including most human-caused mortality, is unavoidable in a dynamic system where hundreds of bears inhabit large areas of diverse habitat with several million human visitors and residents. Adult female mortality influences the population trajectory more than mortality of males or dependent young (Eberhardt 1977, p. 210; Knight and Eberhardt 1985, p. 331; Schwartz

et al.

2006

b,

p. 48). Low adult female survival was the critical factor that caused decline in the GYE population prior to the mid-1980s (Knight and Eberhardt 1985, p. 331). In the early 1980s, with the development of the first Recovery Plan (U.S. Fish and Wildlife Service 1982, pp. 21-24), agencies began to address mortality and increase adult female survivorship (USDA Forest Service 1986, pp. 1-2; Knight

et al.

1999, pp. 56-57).

The Recovery Plan and subsequent supplements to it (U.S. Fish and Wildlife Service 1982, pp. 33-34; U.S. Fish and Wildlife Service 1993, pp. 20-21; U.S. Fish and Wildlife Service 2007

b,

p. 2) established three demographic criteria to objectively measure and monitor recovery of the GYE grizzly bear DMA population. The three parameters that are measured have remained the same since the 1993 plan: (1) Minimum population size for maintaining genetic integrity; (2) population distribution; and (3) total mortality limits that allow continued population health and occupancy of the recovery area. The most current demographic criteria were appended to the 1993 Recovery Plan in 2007, and proposed revisions to those were released for public comment in 2013, though not finalized, as explained above. Further revisions to the demographic criteria are being released for public comment concurrent with this proposed rule. Below, we detail each recovery criterion currently proposed.

Demographic Recovery Criterion 1

—Maintain a population size of at least 500 bears and at least 48 females with cubs in the demographic monitoiring area (DMA) as indicated by methods established in published, peer-reviewed scientific literature and calculated by the IGBST using the most updated protocol as posted on their Web site. The current method (2016) used to estimate population size is the model-averaged Chao2 method. If the estimate of total population size drops below 500 or counts of females with cubs go below 48 unduplicated females with cubs in 3 consecutive years, this criterion will not be met. The population estimate and counts of unduplicated females with cubs will be calculated by the IGBST using data obtained within the DMA.

A minimum population size of at least 500 animals within the DMA will assure genetic health. Population size will be quantified by methods established in published, peer-reviewed scientific literature and calculated by the IGBST using the most updated protocol, as posted on their Web site. This number will ensure the short-term fitness of the population is not threatened by losses in genetic diversity in such an isolated population. Five hundred is a minimum population threshold. The goal is to maintain the population well above this threshold to ensure that genetic issues are not a detriment to the short-term genetic fitness of the GYE grizzly bear population. If the population declined to 500, more than one third of the suitable habitat in the DMA would be unoccupied (van Manen 2015,

in litt.

), and, therefore, the grizzly bear population could not be considered demographically recovered.

The model-averaged Chao2 method is currently the best available science to estimate the total population size in the GYE. The IGBST has been calculating population size on an annual basis using the model-averaged Chao2 (see glossary) estimate since 2002, and this method has been published in the peer-reviewed scientific literature. The model-averaged Chao2 method is the population estimate method that has the lowest amount of annual variation, and it is the most sensitive method to detect increasing or decreasing population trends over time. As the grizzly bear population has increased, model-averaged Chao2 estimates have become increasingly conservative (

i.e.,

prone to underestimation). As a conservative approach to population estimation, the model-averaged Chao2 method will

continue to be the method used to assess Criterion 1 (see U.S. Fish and Wildlife Service 2016, Appendix C, for the application protocol for annual population estimation using the Chao2 method) until a new population estimator is approved. If new methods become available, these will be considered for application in the GYE as long as they represent the best available science. However, until possible new methods are developed, the model-averaged Chao2 method will continue to be used.

Status:

This recovery criterion has been met since 2003 (see IGBST annual reports available at

http://www.nrmsc.usgs.gov/products/IGBST

).

Demographic Recovery Criterion 2

—Sixteen of 18 bear management units within the PCA (see map at

http://www.fws.gov/mountain-prairie/es/grizzlyBear.php

) must be occupied by females with young, with no two adjacent bear management units unoccupied, during a 6-year sum of observations. This criterion is important as it ensures that reproductive females occupy the majority of the PCA and are not concentrated in one portion of the ecosystem.

Status:

This recovery criterion has been met since at least 2001.

Demographic Recovery Criterion 3

—Maintain the population around the 2002-2014 Chao2 modeled average (average = 674; 95% CI = 600-757; 90% CI = 612-735) by maintaining annual mortality limits for independent females, independent males, and dependent young as shown in table 1 in this proposed rule. (These adjustable mortality rates were calculated as those necessary to manage the population to the modeled average of 674 bears which occurred during the time period that this population's growth stabilized.) If mortality limits are exceeded for any sex/age class for 3 consecutive years and any annual population estimate falls below 612 (the lower bound of the 90% confidence interval), the IGBST will produce a Biology and Monitoring Review to inform the appropriate management response. If any annual population estimate falls below 600 (the lower bound of the 95% confidence interval), this criterion will not be met and there will be no discretionary mortality, except as necessary for human safety.

The population had stabilized 2002-2014 at a mean model-averaged Chao2 population size of 674 (95% CI = 600-757), which is very similar to the population size of 683 when the Yellowstone population was previously delisted in 2007 (72 FR 14866; March 29, 2007). The population has now naturally stabilized because of density-dependent population effects that resulted in reduced survival of subadults. The existence of lower subadult survival and occupancy by grizzly bears in almost all suitable habitat inside the DMA has been demonstrated by van Manen

et al.

(2015, entire).

Status:

This criterion has been met for all age and sex classes since 2004.

Table 1—Total Mortality Rate Limits Inside the DMA. These Mortality Rates Were Calculated as Those Limits Necessary To Manage Toward the Long-Term Average Population Size That Occurred From 2002 to 2014 Using the Model-Averaged Chao2 Population Estimate Method (674, 95% CI = 600 -747). If Population Size Is Estimated as Fewer Than or Equal to 600 in Any Year, No Discretionary Mortality Will Occur Unless Necessary for Human Safety

Total grizzly bear population estimate

≤674

675-747

>747

Mortality limit % for independent FEMALES (using model-averaged Chao2 method)

≤7.6%

9%

10%

Mortality limit % for independent MALES (using model-averaged Chao2 method)

15%

20%

22%

Mortality limit for % of DEPENDENT YOUNG (using model-averaged Chao2 method)

≤7.6%

9%

10%

Consistent with USFWS Director Dan Ashe's letter of September 25, 2015, to the state directors, if the model-averaged Chao2 population estimate is less than 674, the total mortality rate for independent females and dependent young will be less than 7.6%.

Total mortality:

Documented known and probable grizzly bear mortalities from all causes including but are not limited to: management removals, illegal kills, mistaken identity kills, self-defense kills, vehicle kills, natural mortalities, undetermined-cause mortalities, grizzly bear hunting, and a statistical estimate of the number of unknown/unreported mortalities.

The Conservation Strategy

The Conservation Strategy is the management plan that institutionalizes the successful program that resulted in the recovery of the GYE population. The Conservation Strategy will guide post-delisting management, just as it has guided management in the GYE since 2007. Recovery of the GYE grizzly bear population is the result of ongoing partnerships between Federal, Tribal, and State agencies; the governors of these States; county and city governments; educational institutions; numerous nongovernmental organizations; private landowners; and the public who live, work, and recreate in the GYE. Just as recovery of the GYE grizzly bear population could not have occurred without these excellent working relationships, maintenance of a recovered grizzly bear population requires continued application of the management actions and partnerships that resulted in the recovery of the grizzly bears and their habitat, and this is what the Conservation Strategy does. Grizzly bears are a “conservation-reliant” species because of their low resiliency to excessive human-caused mortality and the manageable nature of this threat (Scott

et al.

2005, p. 384). This means that for grizzly bears in the GYE to remain recovered there will always need to be careful and cautious management of mortalities and habitat. Consequently, the 2016 Conservation Strategy will remain in effect indefinitely—beyond the 5-year post-delisting monitoring period required by the Act—to facilitate and assure continued successful management of the population and its habitat across multiple land ownerships and jurisdictions.

In order to document the regulatory mechanisms and coordinated management approach necessary to ensure the long-term maintenance of a recovered population, the Recovery Plan calls for the development of “a conservation strategy to outline habitat and population monitoring that will continue in force after recovery” (Recovery Plan Task Y426) (U.S. Fish and Wildlife Service 1993, p. 55). To accomplish this goal, a Conservation Strategy Team was formed in 1993. This team included biologists and managers from the Service, National Park Service,

Forest Service, U.S. Geological Survey (USGS), IDFG, WGFD, and MTFWP.

In March 2000, a draft Conservation Strategy for the GYE was released for public review and comment (65 FR 11340; March 2, 2000). Also in 2000, a Governors' Roundtable was organized to provide recommendations from the perspectives of the three States that would be involved with grizzly bear management after delisting. In 2003, the draft Final Conservation Strategy for the Grizzly Bear in the GYE was released, along with drafts of State grizzly bear management plans (all accessible at

http://www.fws.gov/mountain-prairie/es/grizzlyBear.php

). We responded to all public comments and peer reviews received on the Conservation Strategy and finalized the Conservation Strategy in 2007 (72 FR 11376; March 13, 2007). Revisions have been made to the Conservation Strategy and a draft 2016 Conservation Strategy is presented for public comment concurrent with this proposed rule (accessible at

http://www.fws.gov/mountain-prairie/es/grizzlyBear.php

).

The purposes of the Conservation Strategy and associated State and Federal implementation plans are to: (1) Describe, summarize, and implement the coordinated efforts to manage the grizzly bear population and its habitat to ensure continued conservation of the GYE grizzly bear population; (2) specify and implement the population/mortality management, habitat, and nuisance bear standards to maintain a recovered grizzly bear population for the future; (3) document specific State and Federal regulatory mechanisms and legal authorities, policies, management, and monitoring programs that exist to maintain the recovered grizzly bear population; and (4) document the actions that participating agencies have agreed to implement (U.S. Fish and Wildlife Service 2016, Executive Summary).

Implementation of the Conservation Strategy by all agency partners will coordinate management and monitoring of the GYE grizzly bear population and its habitat after delisting. The draft 2016 Conservation Strategy establishes and details a regulatory framework and authority for Federal and State agencies to take over management of the GYE grizzly bear population from the Service. The draft 2016 Conservation Strategy also identifies, defines, and requires adequate post-delisting monitoring to maintain a healthy GYE grizzly bear population (U.S. Fish and Wildlife Service 2016, Chapters 2 and 3). The draft 2016 Conservation Strategy has objective, measurable habitat and population standards, with clear State and Federal management responses if deviations occur (U.S. Fish and Wildlife Service 2016, Chapter 6). It represents 20 years of a collaborative, interagency effort among the members of the Yellowstone Ecosystem Subcommittee. State grizzly bear management plans were developed in all three affected States (Idaho, Montana, and Wyoming). Revised state plans will be incorporated into the final 2016 Conservation Strategy as appendices to ensure that the plans and the Conservation Strategy are consistent and complementary (accessible at

http://www.fws.gov/mountain-prairie/es/grizzlyBear.php

). If the State plans change from those available for comment appended to this draft Strategy, these revised State plans will be available for public comment and finalized prior to a final determination on this proposed rule. All the State and Federal agencies party to the draft 2016 Conservation Strategy will need to sign a memorandum of understanding agreeing to implement the revised 2016 Conservation Strategy prior to a final rule.

The draft 2016 Conservation Strategy identifies and provides a framework for managing habitat within the PCA and managing demographic parameters within the DMA (see figure 2, above). The PCA contains adequate seasonal habitat components for a portion of the recovered GYE grizzly bear population for the future and to allow bears to continue to expand outside the PCA. The PCA includes approximately 51 percent of suitable grizzly bear habitat within the GYE and approximately 75 percent of the population of female grizzly bears with cubs (Haroldson 2014,

in litt.

) (For more information about what constitutes “suitable habitat,” see the suitable habitat discussion under Factor A, below).

The 2016 Conservation Strategy will be implemented and funded by Federal, Tribal, and State agencies within the GYE. The signatories to the final 2016 Conservation Strategy have a demonstrated track record of funding measures to ensure recovery of this grizzly bear population for more than 3 decades. The Service intends to continue contributing funding to the implementation of the 2016 Conservation Strategy. In general, the Forest Service and National Park Service will be responsible for habitat management to reduce the risk of human-caused mortality to grizzly bears while the National Park Service, and State and Tribal wildlife agencies, will be responsible for managing the population within specific total mortality limits. The Forest Service and National Park Service collectively manage approximately 98 percent of lands inside the PCA. Specifically, Yellowstone National Park; Grand Teton National Park; and the Shoshone, Beaverhead-Deerlodge, Bridger-Teton, Caribou-Targhee, and Custer-Gallatin National Forests are the Federal entities responsible for implementing the 2016 Conservation Strategy. Affected National Forests and National Parks have incorporated, or will incorporate before a final rule is issued, the habitat standards and criteria into their Forest Plans and National Park management plans and/or Superintendent's Compendia via appropriate amendment processes so that they are legally applied to these public lands within the GYE (see Grand Teton National Park 2006, p. 1; USDA Forest Service 2006

b,

p. 4; Yellowstone National Park 2006, p. 12). Outside of the PCA, grizzly bear habitat is well protected via Wilderness Area designation (Wilderness or Wilderness Study Area) or Forest Plan direction, and demographic standards will protect the population throughout the DMA.

If this proposed rule is made final, the Yellowstone Grizzly Bear Coordinating Committee (hereafter referred to as the YGCC) will replace the Yellowstone Ecosystem Subcommittee as the interagency group coordinating implementation of the 2016 Conservation Strategy's habitat and population standards, and monitoring (U.S. Fish and Wildlife Service 2016, Chapter 6). Similar to the Yellowstone Ecosystem Subcommittee, the YGCC members include representatives from Yellowstone and Grand Teton National Parks, the five affected National Forests, BLM, USGS, IDFG, MTFWP, WGFD, one member from local county governments within each State, and one member from the Shoshone Bannock, Northern Arapahoe, and Eastern Shoshone Tribes. All meetings will be open to the public. Besides coordinating management, research, and financial needs for successful conservation of the GYE grizzly bear population, the YGCC will review the IGBST Annual Reports and review and respond to any deviations from habitat or population standards. As per the implementation section of the 2016 Conservation Strategy, the YGCC will coordinate management and implementation of the 2016 Conservation Strategy and work together to rectify problems and to assure that the habitat and population standards and total mortality limits will be met and maintained.

The draft 2016 Conservation Strategy is an adaptive, dynamic document that establishes a framework to incorporate new and better scientific information as

it becomes available or as necessary in response to environmental changes. Any changes and updates to the 2016 Conservation Strategy must meet the following two criteria: (1) Be based on the best available science; and (2) be subject to public comment before being implemented by the YGCC (U.S. Fish and Wildlife Service 2016, Chapter 1).

Distinct Vertebrate Population Segment Policy Overview

Section 4 of the Act and its implementing regulations (50 CFR part 424) set forth the procedures for listing species, reclassifying species, or removing species from listed status. “Species” is defined by the Act as including any species or subspecies of fish or wildlife or plants, and any distinct vertebrate population segment of fish or wildlife that interbreeds when mature (16 U.S.C. 1532(16)). We, along with the National Marine Fisheries Service (now the National Oceanic and Atmospheric Administration—Fisheries), developed the Policy Regarding the Recognition of Distinct Vertebrate Population Segments (DPS policy) (61 FR 4722; February 7, 1996), to help us in determining what constitutes a distinct population segment (DPS). Under this policy, the Service considers two factors to determine whether the population segment is a valid DPS: (1) Discreteness of the population segment in relation to the remainder of the taxon to which it belongs; and (2) the significance of the population segment to the taxon to which it belongs. If a population meets both tests, it is a DPS, and the Service then evaluates the population segment's conservation status according to the standards in section 4 of the Act for listing, delisting, or reclassification (

i.e.,

is the DPS endangered or threatened). Our policy further recognizes it may be appropriate to assign different classifications (

i.e.,

endangered or threatened) to different DPSs of the same vertebrate taxon (61 FR 4725; February 7, 1996).

Past Practice and History of Using DPSs

As of February 9, 2016, of the 436 native vertebrate listings, 89 are listed as less than an entire taxonomic species or subspecies (henceforth referred to in this discussion as populations) under one of several authorities, including the “distinct population segment” language in the Act's definition of species (section 3(16)). Twenty-three of these 89 populations, which span 5 different taxa, predate the 1996 DPS Policy; as such, the final listing determinations for these populations did not include formal policy-based analyses or expressly designate the listed entity as a DPS. In several instances, however, the Service and National Marine Fisheries Service (NMFS) have established a DPS and revised the List of Endangered and Threatened Wildlife in a single action, as shown in the following examples.

In February 1985, the Service delisted the brown pelican (

Pelecanus occidentalis

) in the southeastern United States and continued to identify it as endangered throughout the remainder of its range (50 FR 4938; February 4, 1985). The Service later went on to delist the brown pelican in the remainder of its range (74 FR 59444; November 17, 2009). In June 1994, NMFS revised the entry for the gray whale (

Eschrichtius robustus

) to remove the eastern North Pacific population from the List of Endangered and Threatened Wildlife while retaining the western North Pacific population as endangered (59 FR 31094; June 16, 1994). In May 1997, NMFS identified the western and eastern DPSs of the Steller sea lion (

Eumetopias jubatus

), which had been listed as threatened, and listed the western DPS as endangered (62 FR 24345; May 5, 1997). In July 2003, the Service established two DPSs of the Columbian white-tailed deer (

Odocoileus virginianus leucurus

)—the Douglas County DPS and the Columbia River DPS—and delisted only the Douglas County DPS, while retaining listed status for the Columbia River DPS (68 FR 43647; July 24, 2003). The Columbia River DPS was recently proposed for reclassification to threatened (October 8, 2015; 80 FR 60850). In March 2007, the Service identified the American crocodile (

Crocodylus acutus

) in Florida as a DPS within the existing endangered listing of the American crocodile and reclassified the Florida DPS from endangered to threatened (72 FR 13027; March 20, 2007). In September 2011, the Service and NMFS jointly determined the loggerhead sea turtle (

Caretta caretta

) is composed of nine DPSs and replaced the species-wide listing with four DPSs as threatened and five DPSs as endangered (76 FR 58868; September 22, 2011). The Service and NMFS have jointly proposed to make similar revisions to the species-wide listing for the green sea turtle (

Chelonia mydas

), and NMFS has also recently proposed to revise the global listing for humpback whale (

Megaptera novaeangliae

) (80 FR 15272; March 23, 2015, and 80 FR 22304; April 21, 2015, respectively). Revising the lower 48 State listing for grizzly bear by removing the GYE DPS is consistent with the Service's past and practice.

Our authority to make these determinations and to revise the list accordingly is a reasonable interpretation of the language of the Act, and our ability to do so is an important component of the Service's program for the conservation of endangered and threatened species. Our authority to revise the existing listing of a species (the grizzly bear in the lower 48 States) to identify a GYE DPS and determine that it is healthy enough that it no longer needs the Act's protections is found in the precise language of the Act. Moreover, even if that authority were not clear, our interpretation of this authority to make determinations under section 4(a)(1) of the Act and to revise the endangered and threatened species list to reflect those determinations under section 4(c)(1) of the Act is reasonable and fully consistent with the Act's text, structure, legislative history, relevant judicial interpretations, and policy objectives.

On December 12, 2008, a formal opinion was issued by the Solicitor, “U.S. Fish and Wildlife Service Authority Under Section 4(c)(1) of the Endangered Species Act to Revise Lists of Endangered and Threatened Species to `Reflect Recent Determinations' ” (U.S. DOI 2008). The Service fully agrees with the analysis and conclusions set out in the Solicitor's opinion. This proposed action is consistent with the opinion. The complete text of the Solicitor's opinion can be found at

https://www.doi.gov/sites/doi.opengov.ibmcloud.com/files/uploads/M-37018.pdf

.

We recognize that our interpretation and use of the DPS policy to revise and delist distinct population segments has been challenged in

Humane Society of the United States

v.

Jewell,

76 F.Supp.3d 69 (D. D.C. 2014). Partly at issue in that case was our application of the DPS policy to Western Great Lakes wolves in a delisting rule (76 FR 81666; December 28, 2011). Our rule was vacated by the district court's decision. We respectfully disagree with the district court's interpretation of the DPS policy, and the United States has appealed that decision.

In the 1993 Grizzly Bear Recovery Plan, the Service identifies six grizzly bear Recovery Zones and identifies unique demographic recovery criteria for each one. The 1993 Recovery Plan states that it is the intent of the Service to delist individual populations as they achieve recovery (U.S. Fish and Wildlife Service 1993, p. ii). The Service has proceeded in a manner consistent with the Recovery Plan with respect to

individual population treatment. For example, grizzly bears in the Cabinet-Yaak, Selkirk, and North Cascades Recovery Zones, all included in the original threatened grizzly bear listing, were petitioned for reclassification from threatened to endangered. Although already listed as threatened, we determined that reclassifying those grizzly bears to endangered was warranted but precluded by higher priorities. After 2014, the Service determined that the Cabinet-Yaak and Selkirk populations had recovered to the point that they were no longer warranted but precluded from listing as endangered; they remain listed as threatened. Grizzly bears in the North Cascades Recovery Zone are still warranted but precluded for reclassification from threatened to endangered. The Bitterroot Recovery Zone now has status under section 10(j) of the Act, which authorizes the Service to release an experimental population of grizzly bears in that Recovery Zone.

Distinct Vertebrate Population Segment Analysis

Analysis of Discreteness in Relation to Remainder of Taxon

Under our DPS Policy, a population of a vertebrate taxon may be considered discrete if it satisfies either one of the following conditions: (1) It is markedly separated from other populations of the same taxon (

i.e., Ursus arctos horribilis

) as a consequence of physical, physiological, ecological, or behavioral factors (quantitative measures of genetic or morphological discontinuity may provide evidence of this separation); or (2) it is delimited by international governmental boundaries within which differences in control of exploitation, management of habitat, conservation status, or regulatory mechanisms exist that are significant in light of section 4(a)(1)(D) (“the inadequacy of existing regulatory mechanisms”) of the Act. The DPS Policy does not require complete separation of one DPS from another, and occasional interchange does not undermine the discreteness of potential DPSs. If complete separation is required, the loss of the population has little significance to other populations (61 FR 4722, 4724). The DPS policy only requires that populations be “markedly separated” from each other. Thus, if occasional individual grizzly bears move between populations, the population could still display the required level of discreteness per the DPS Policy. The standard adopted allows for some limited interchange among population segments considered to be discrete, so that loss of an interstitial population could well have consequences for gene flow and demographic suitability of a species as a whole.

Although the DPS Policy does not allow State or other intra-national governmental boundaries to be used as the basis for determining the discreteness of a potential DPS, an artificial or human-made boundary may be used to clearly identify the geographic area included within a DPS designation. Easily identified human-made objects, such as the center line of interstate highways, Federal highways, and State highways are useful for delimiting DPS boundaries. Thus, the proposed GYE grizzly bear DPS consists of: That portion of Idaho that is east of Interstate Highway 15 and north of U.S. Highway 30; that portion of Montana that is east of Interstate Highway 15 and south of Interstate Highway 90; and that portion of Wyoming that is south of Interstate Highway 90, west of Interstate Highway 25, west of Wyoming State Highway 220, and west of U.S. Highway 287 south of Three Forks (at the 220 and 287 intersection, and north of Interstate Highway 80 and U.S. Highway 30) (see DPS boundary in figure 2, above). Due to the use of highways as easily described boundaries, large areas of unsuitable habitat are included in the proposed DPS boundaries.

The core of the proposed GYE grizzly bear DPS is the Yellowstone PCA (24,000 sq km (9,200 sq mi)) (U.S. Fish and Wildlife Service 1993, p. 39). The Yellowstone PCA includes Yellowstone National Park; a portion of Grand Teton National Park; John D. Rockefeller Memorial Parkway; sizable contiguous portions of the Shoshone, Bridger-Teton, Caribou-Targhee, Custer-Gallatin, and Beaverhead-Deerlodge National Forests; BLM lands; and surrounding State and private lands (U.S. Fish and Wildlife Service 1993, p. 39). As grizzly bear populations have rebounded and densities have increased, bears have expanded their range beyond the PCA, into other suitable habitat in the DMA. Grizzly bears now occupy about 44,624 sq km (17,229 sq mi) or 89 percent of the GYE DMA (Haroldson 2015,

in litt.

), with occasional occurrences well beyond this estimate of occupied range. No grizzly bears originating from the Yellowstone PCA have been suspected or confirmed beyond the borders of the GYE grizzly bear DPS described above. Similarly, no grizzly bears originating from other Recovery Zones have been detected inside the borders of the GYE grizzly bear DPS (Wildlife Genetics International 2015,

in litt.

).

The GYE grizzly bear population is the southernmost population remaining in the conterminous United States and has been physically separated from other areas where grizzly bears occur for at least 100 years (Merriam 1922, pp. 1-2; Miller and Waits 2003, p. 4334). The nearest population of grizzly bears is found in the NCDE approximately 160 km (100 mi) to the north. Although their range continues to expand north (Bjornlie

et al.

2013, p. 185), grizzly bears from the GYE have not been documented north of Interstate 90 outside the proposed DPS boundaries (Frey 2014,

in litt.

). Over the last few decades, the NCDE grizzly bear population has been slowly expanding to the south, and there have been several confirmed grizzly bears from the NCDE within 32 to 80 km (20 to 50 mi) of the GYE grizzly bear DPS boundaries near Butte, Deerlodge, and Anaconda, Montana (Jonkel 2014,

in litt.

). However, there is currently no known connectivity between these two grizzly bear populations.

Genetic data also support the conclusion that grizzly bears from the GYE are separated from other grizzly bears. Genetic studies estimating heterozygosity (which provides a measure of genetic diversity) show 60 percent heterozygosity in the GYE grizzly bears compared to 67 percent in the NCDE grizzly bears (Haroldson

et al.

2010, p. 7). Heterozygosity is a useful measure of genetic diversity, with higher values indicative of greater genetic variation and evolutionary potential. High levels of genetic variation are indicative of high levels of connectivity among populations or high numbers of breeding animals. By comparing heterozygosity of extant bears to samples from Yellowstone grizzly bears of the early 1900s, Miller and Waits (2003, p. 4338) concluded that gene flow and, therefore, population connectivity between the GYE grizzly population and populations to the north was low even 100 years ago. The reasons for this historic limitation of gene flow are unclear, but we do know increasing levels of human activity and settlement in this intervening area over the last century further limited grizzly bear movements into and out of the GYE, likely resulting in the current lack of connectivity (Proctor

et al.

2012, p. 35).

Based on the best available scientific data about grizzly bear locations and movements, we find that the GYE grizzly bear population and other remaining grizzly bear populations are markedly, physically separated from each other. Therefore, the GYE grizzly bear population meets the criterion of discreteness under our DPS Policy. Occasional movement of bears from

other grizzly bear populations into the GYE grizzly bear population would be beneficial to its long-term persistence (Boyce

et al.

2001, pp. 25, 26). While future connectivity is desirable and will be actively managed for, this would not undermine discreteness, as all that is required is “marked separation,” not absolute separation. Even if occasional individual grizzly bears disperse among populations, the GYE grizzly bear population would still display the required level of discreteness per the DPS Policy. And, as stated in the 1993 Recovery Plan, we recognize that natural connectivity is important to long-term grizzly bear conservation, and we will continue efforts to work toward this goal independent of the delisting of the GYE grizzly bear DPS (U.S. Fish and Wildlife Service 1993, p. 53). This issue is discussed further under Factor E below.

Analysis of Significance of Population Segment to Taxon

If we determine a population segment is discrete under one or more of the conditions described in the Service's DPS policy, its biological and ecological significance will then be considered in light of Congressional guidance that the authority to list DPS's be used “sparingly” while encouraging the conservation of genetic diversity (see Senate Report 151, 96th Congress, 1st Session). In carrying out this examination, we consider available scientific evidence of the population's importance to the taxon (

i.e., Ursus arctos horribilis

) to which it belongs. Since precise circumstances are likely to vary considerably from case to case, the DPS policy does not describe all the classes of information that might be used in determining the biological and ecological importance of a discrete population. However, the DPS policy describes four possible classes of information that provide evidence of a population segment's biological and ecological importance to the taxon to which it belongs. As specified in the DPS policy (61 FR 4722; February 7, 1996), this consideration of the population segment's significance may include, but is not limited to, the following: (1) Persistence of the discrete population segment in an ecological setting unusual or unique for the taxon; (2) Evidence that loss of the discrete population segment would result in a significant gap in the range of the taxon; (3) Evidence that the discrete population segment represents the only surviving natural occurrence of a taxon that may be more abundant elsewhere as an introduced population outside its historic range; or (4) Evidence that the discrete population segment differs markedly from other populations of the species in its genetic characteristics. To be considered significant, a population segment needs to satisfy only one of these conditions, or other classes of information that might bear on the biological and ecological importance of a discrete population segment, as described in the DPS policy (61 FR 4722; February 7, 1996). Below we address Factors 1, 2, and 4. Factor 3 does not apply to the GYE grizzly bear population because there are several other extant populations of grizzly bears in North America.

Unusual or Unique Ecological Setting

New information since the publication of the March 29, 2007, final rule (72 FR 14866) and the 2011 status review (U.S. Fish and Wildlife Service 2011) calls into question whether the GYE is truly a unique ecological setting. Previously, we concluded that the GYE was a unique ecological setting because grizzly bears were more carnivorous there than in other ecosystems in the lower 48 States and that they still used whitebark pine seeds extensively while other populations no longer did.

Based on previous research, we found that meat constitutes 45 percent and 79 percent of the annual diet for females and males in the GYE, respectively (Jacoby

et al.

1999, p. 925). These high percentages of meat in GYE grizzly bears' diet appeared to be in contrast with the 0 to 33 percent of meat in the diet of bears in the NCDE and 0 to 17 percent of meat in the diet of bears from the Cabinet-Yaak Ecosystem (Jacoby

et al.

1999, p. 925). However, these analyses were recently revisited and supplemented with larger sample sizes with very different results. First, Schwartz

et al.

(2014, p. 75) found that meat constitutes 44 percent of the annual diet among grizzly bears in the GYE, with no statistical difference among sex and age groups. For the Yellowstone Lake area, Fortin

et al.

(2013, p. 275) found that meat constitutes 38 percent and 45 percent of the annual diet for females and males in the GYE, respectively. These levels are very similar to those in the NCDE, where meat constitutes 38 percent and 56 percent of the annual diet for females and males, respectively (Teisberg

et al.

2014, p. 7). Previous information also indicated that bison, a species endemic to North America, accounted for up to 24 percent of ungulate meat in GYE grizzly bear diets (Mattson 1997, p. 167). However, Fortin

et al.

(2013, p. 275) found bison comprise only about 9 percent of grizzly bear diets around the Yellowstone Lake area, possibly indicating grizzly bears do not use this endemic food source as much as previously thought in the GYE.

We also previously concluded the GYE grizzly bear population exists in a unique ecological setting because it is able to use whitebark pine seeds as a major food source (see 72 FR 14866; March 29, 2007). We considered the use of whitebark pine seeds by GYE grizzly bears unique because in most areas of its range, whitebark pine has been significantly reduced in numbers and distribution due to the introduced pathogen white pine blister rust (

Cronartium ribicola

) (Kendall and Keane 2001, pp. 228-232). New information indicates that whitebark pine has also been reduced in the GYE since 2002 due to a mountain pine beetle epidemic. Since this time, bears have been documented using whitebark pine less frequently. A recent study using GPS data indicated nearly one third of sampled grizzly bears in the GYE did not even have whitebark pine within their home ranges (Costello

et al.

2014, p. 2009). Grizzly bears in the GYE do not seek out whitebark pine in years of poor seed production but make use of other foods within their home ranges instead (Costello

et al.

2014, p. 2013). Additionally, methods used by Felicetti

et al.

(2003, entire) to assess whitebark pine use in the GYE may not be as reliable as previously thought because other foods in the GYE could be mistakenly identified as whitebark pine, indicating more use than is actually occurring (Schwartz

et al.

2014, p. 6).

In light of these new data indicating grizzly bears in the GYE do not consume more meat than other populations in the lower 48 States and their use of whitebark pine has waned, we no longer consider the GYE grizzly bear population to meet the DPS policy standard for significance based on its persistence in an ecological setting unusual or unique for the taxon.

Significant Gap in the Range of the Taxon

Given the grizzly bear's historic occupancy of the conterminous United States and the portion of the historic range the conterminous United States represent, recovery in the lower 48 States where the grizzly bear existed in 1975 when it was listed has long been viewed as important to the taxon (40 FR 31734; July 28, 1975). The GYE grizzly bear population is significant in achieving this objective, as it is one of only five known occupied areas and one unoccupied area and constitutes approximately half of the estimated number of grizzly bears remaining in the conterminous 48 States. As noted above,

grizzly bears once lived throughout the North American Rockies from Alaska and Canada, and south into central Mexico. Grizzly bears have been extirpated from most of the southern portions of their historic range. Today, the GYE grizzly bear population represents the southernmost reach of the taxon. The loss of this population would significantly impact representation of the species because it would substantially curtail the range of the grizzly bear in North America by moving the range approximately 3 degrees of latitude or 200 mi (350 km) to the north. Therefore, we find that the GYE population of grizzly bears meets the significance criterion under our DPS policy because its loss would represent a significant gap in the range of the taxon.

Marked Genetic Differences

Several studies have documented some level of genetic differences between grizzly bears in the GYE and other populations in North America (Paetkau

et al.

1998, pp. 421-424; Waits

et al.

1998, p. 310; Proctor

et al.

2012, p. 12). The GYE population has been isolated from other grizzly bear populations for 100 years or more (Miller and Waits 2003, p. 4334). However, Miller and Waits (2003, p. 4334) could only speculate as to the reasons behind this historical separation or how long it had been occurring. Proctor

et al.

(2012, p. 35) concluded that observed differences in heterozygosity among grizzly bear populations in southern Canada and the United States were an artifact of human-caused habitat fragmentation, not the result of different evolutionary pressures selecting for specific traits. We do not know whether these differences in heterozygosity levels are biologically meaningful, and we have no data indicating they are. Because we do not know the biological significance (if any) of the observed differences, we cannot say with certainty that the GYE grizzly bear population's genetics differ “markedly” from other grizzly bear populations. Therefore, we do not consider these genetic differences to meet the DPS policy's standard for significance.

In summary, while we no longer consider the GYE grizzly bear population to be significant due to unique ecological conditions or marked genetic differences, we still conclude that the GYE grizzly bear population is significant because the loss of this population would result in a significant gap in the range of the taxon.

Summary of Distinct Population Segment Analysis

Based on the best scientific and commercial data available, as described above, we find that the GYE grizzly bear population is discrete from other grizzly bear populations and significant to the remainder of the taxon (

i.e., Ursus arctos horribilis

). Because the GYE grizzly bear population is discrete and significant, it meets the definition of a DPS under the Act. Therefore, the GYE grizzly bear DPS is a listable entity under the Act, and we now assess this DPS's conservation status in relation to the Act's standards for listing, delisting, or reclassification (

i.e.,

whether this DPS meets the definition of an endangered or threatened species under the Act).

Summary of Factors Affecting the Species

Section 4 of the Act and its implementing regulations (50 CFR part 424) set forth the procedures for listing species, reclassifying species, or removing species from listed status. “Species” is defined by the Act as including any species or subspecies of fish or wildlife or plants, and any distinct vertebrate population segment of fish or wildlife that interbreeds when mature (16 U.S.C. 1532(16)). A species may be determined to be an endangered or threatened species due to one or more of the five factors described in section 4(a)(1) of the Act: (A) The present or threatened destruction, modification, or curtailment of its habitat or range; (B) overutilization for commercial, recreational, scientific, or educational purposes; (C) disease or predation; (D) the inadequacy of existing regulatory mechanisms; or (E) other natural or manmade factors affecting its continued existence. We must consider these same five factors in delisting a species. We may delist a species according to 50 CFR 424.11(d) if the best available scientific and commercial data indicate that the species is neither endangered nor threatened for the following reasons: (1) The species is extinct; (2) the species has recovered and is no longer endangered or threatened; and/or (3) the original scientific data used at the time the species was classified were in error.

A recovered species is one that no longer meets the Act's definition of endangered or threatened. A species is endangered for purposes of the Act if it is in danger of extinction throughout all or a significant portion of its range (SPR) and is threatened if it is likely to become endangered within the foreseeable future throughout all or a significant portion of its range. The word “range” in these definitions refers to the range in which the species currently exists. Determining whether a species is recovered requires consideration of the same five categories of threats specified in section 4(a)(1) of the Act. For species that are already listed as endangered or threatened, this analysis of threats is an evaluation of both the threats currently facing the species and the threats that are reasonably likely to affect the species in the foreseeable future following the removal of the Act's protections.

In considering what factors might constitute threats, we must look beyond the exposure of the species to a particular factor to evaluate whether the species may respond to the factor in a way that causes actual impacts to the species. If there is exposure to a factor and the species responds negatively, the factor may be a threat, and during the five-factor threats analysis, we attempt to determine how significant a threat it is. The threat is significant if it drives or contributes to the risk of extinction of the species such that the species warrants listing as endangered or threatened as those terms are defined by the Act. However, the identification of factors that could affect a species negatively may not be sufficient to justify a finding that the species warrants listing. The information must include evidence sufficient to suggest that the potential threat is likely to materialize and that it has the capacity (

i.e.,

it should be of sufficient magnitude and extent) to affect the species' status such that it meets the definition of endangered or threatened under the Act. The following analysis examines the five factors affecting, or likely to affect, the GYE grizzly bear population within the foreseeable future. We previously concluded GYE grizzly bears are recovered and warranted delisting (72 FR 14866; March 29, 2007). In this proposed rule, we make a determination as to whether the distinct population segment of GYE grizzly bears is an endangered or threatened species, based on the best scientific and commercial information available. In so doing, we address the issues raised by the Ninth Circuit in

Greater Yellowstone Coalition

v.

Servheen,

665 F.3d 1015 (9th Cir. 2011), which were briefly discussed above.

A. The Present or Threatened Destruction, Modification, or Curtailment of Its Habitat or Range

Factor A requires the Service to consider present or threatened destruction, modification, or curtailment of grizzly bear habitat or its range. Here, the following

considerations warrant discussion regarding the GYE grizzly bear population: (1) Motorized access management, (2) developed sites, (3) livestock allotments, (4) mineral and energy development, (5) recreation, (6) snowmobiling, (7) vegetation management, (8) climate change, and (9) habitat fragmentation.

Habitat destruction and modification were contributing factors leading to the listing of the grizzly bear as a threatened species under the Act in 1975 (40 FR 31734; July 28, 1975). Both the dramatic decreases in historical range and land management practices in formerly secure grizzly bear habitat led to the 1975 listing (40 FR 31734; July 28, 1975). For consideration under the Act, the word range applies to where the species currently exists. To address this source of population decline, the IGBST was created in 1973, to collect, manage, analyze, and distribute science-based information regarding habitat and demographic parameters upon which to base management and recovery. Then, in 1983, the Interagency Grizzly Bear Committee (IGBC) was created to coordinate management efforts across multiple Federal lands and different States within the various Recovery Zones ultimately working to achieve recovery of the grizzly bear in the lower 48 States. Its objective was to change land management practices on Federal lands that supported grizzly bear populations at the time of listing to provide security and maintain or improve habitat conditions for the grizzly bear. Since 1986, National Forest and National Park plans have incorporated the Interagency Grizzly Bear Guidelines (USDA Forest Service 1986, pp. 1-2) to manage grizzly bear habitat in the Yellowstone PCA.

Management improvements made as a result of the Interagency Grizzly Bear Guidelines include, but are not limited to: (1) Federal and State agency coordination to produce nuisance bear guidelines that allow a quick response to resolve and minimize grizzly bear-human confrontations; (2) reduced motorized access route densities through restrictions, decommissioning, and closures; (3) highway design considerations to facilitate population connectivity; (4) seasonal closure of some areas to all human access in National Parks that are particularly important to grizzly bears; (5) closure of many areas in the GYE to oil and gas leasing, or implementing restrictions such as no surface occupancy; (6) elimination of six active and four vacant sheep allotments on the Caribou-Targhee National Forest since 1998, resulting in an 86 percent decrease in total sheep animal months inside the Yellowstone PCA; and (7) expanded information and education programs in the Yellowstone PCA to help reduce the number of grizzly bear mortalities caused by big-game hunters (outside National Parks). Overall, adherence to the Interagency Grizzly Bear Guidelines has changed land management practices on Federal lands to provide security and to maintain or improve habitat conditions for the grizzly bear. Implementation of these guidelines has led to the successful rebound of the GYE grizzly bear population, allowing it to significantly increase in size and distribution since its listing in 1975.

Concurrent with this proposed rule, an interagency group representing pertinent State and Federal parties is releasing a draft 2016 Conservation Strategy for the grizzly bear in the GYE to guide management and monitoring of the habitat and population of GYE grizzly bears after delisting. The draft 2016 Conservation Strategy will be the most recent iteration of the Conservation Strategy, which was first published in final form in 2007 (see our notice of availability published on March 13, 2007, at 72 FR 11376). The draft 2016 Conservation Strategy incorporates the explicit and measurable habitat criteria established in the “Recovery Plan Supplement: Habitat-based Recovery Criteria for the Greater Yellowstone Ecosystem” (U.S. Fish and Wildlife Service 2007

b

). Whereas the Interagency Grizzly Bear Guidelines helped to guide successful recovery efforts, the 2016 Conservation Strategy will help guide the recovered GYE population post-delisting. The draft 2016 Conservation Strategy identifies and provides a framework for managing two areas, the PCA and adjacent areas of the DMA, where occupancy by grizzly bears is anticipated in the foreseeable future. What follows is an assessment of present or threatened destruction, modification, or curtailment of the grizzly bear's habitat within the PCA and adjacent areas of the DMA.

Habitat Management Inside the Primary Conservation Area

As per the draft 2016 Conservation Strategy and the habitat-based recovery criteria discussed above, the PCA will be a core secure area for grizzly bears where human impacts on habitat conditions will be maintained at or below levels that existed in 1998 (U.S. Fish and Wildlife Service 2016, chapter 3). Specifically, the amount of secure habitat will not decrease below 1998 levels while the number of developed sites and livestock allotments will not increase above 1998 levels. The 1998 baseline for habitat standards was chosen because the levels of secure habitat and developed sites on public lands remained relatively constant in the 10 years preceding 1998 (USDA Forest Service 2004, pp. 140-141), and the selection of 1998 assured that habitat conditions existing at a time when the population was increasing at a rate of 4 to 7 percent per year (Schwartz

et al.

2006

b,

p. 48) would be maintained. For each of the 40 bear management subunits, the 1998 baseline was determined through a GIS analysis of the amount of secure habitat, open and closed road densities, the number and capacity of livestock allotments, and the number of developed sites on public lands.

Motorized Access Management:

When we listed the grizzly bear in 1975, we identified land management practices that create new ways for humans to access formerly secure grizzly bear habitat as the mechanism that resulted in bears being more susceptible to the threat of human-caused mortality and human-bear conflicts (40 FR 31734; July 28, 1975). We recognized early on that managing this human access to grizzly bears would be the key to effective habitat management and an extensive body of literature supports this approach. Specifically, unmanaged motorized access impacts grizzly bears by: (1) Increasing human interaction and potential grizzly bear mortality risk; (2) increasing displacement from important habitat; (3) increasing habituation to humans; and (4) decreasing habitat where energetic requirements can be met with limited disturbance from humans (Mattson

et al.

1987, pp. 269-271; McLellan and Shackleton 1988, pp. 458-459; McLellan 1989, pp. 1862-1864; Mace

et al.

1996, pp. 1402-1403; Schwartz

et al.

2010, p.661).

Motorized access affects grizzly bears primarily through increased human-caused mortality risk (Schwartz

et al.

2010, p. 661). Secondarily, motorized access may affect grizzly bears through temporary or permanent habitat loss due to human disturbance. Managing motorized access by providing large proportions of secure habitat helps ameliorate the impacts of displacement and increased human-caused mortality risk in grizzly bear habitat. Secure habitat refers to those areas with no motorized access that are at least 4 ha (10 ac) in size and more than 500 m (1,650 ft) from a motorized access route or recurring helicopter flight line (USDA Forest Service 2004, pp. 160-161). In the 1998 baseline, secure habitat comprised 45.4 to 100 percent of the total area within a given subunit with an

average of 85.6 percent throughout the entire PCA (U.S. Fish and Wildlife Service 2016, Appendix E). These levels of secure habitat have been successfully maintained and will continue to be maintained or improved, as directed by the draft 2016 Conservation Strategy and the memorandum of understanding (MOU) signed by all State and Federal partner agencies (U.S. Fish and Wildlife Service 2016, MOU). Three subunits were identified as in need of improvement from 1998 levels. These subunits have shown on average a 7.5 percent increase in secure habitat and these improved levels will serve as the new baseline for these three subunits with the implementation of the 2006 Gallatin National Forest Travel Management Plan (

in prep.

). Because of the positive effect that secure habitat has on grizzly bear survival and reproduction, one of the draft 2016 Conservation Strategy objectives is no net decrease in these levels of secure habitat inside the PCA so that the PCA can continue to function as a source area for grizzly bears in the GYE. Therefore, we do not foresee that decreases in secure habitat inside the PCA will pose a threat to the GYE grizzly bear DPS now, or in the future.

Developed Sites:

The National Parks and National Forests within the PCA will manage developed sites at 1998 levels within each bear management subunit, with some exceptions for administrative and maintenance needs (U.S. Fish and Wildlife Service 2016, Chapter 3). “Developed sites” refer to those sites or facilities on public land with features intended to accommodate public use or recreation. Such sites are typically identified or advertised via visitor maps or information displays as identifiable destination sites promoted by the agency. Examples of developed sites include, but are not limited to, campgrounds, picnic areas, trailheads, boat launches, rental cabins, summer homes, lodges, service stations, restaurants, visitor centers, administrative sites, and permitted resource exploration or extraction sites such as oil and gas exploratory wells, production wells, plans of operation for mining activities, and work camps. “Administrative sites” are those sites or facilities constructed for use primarily by government employees to facilitate the administration and management of public lands. Administrative sites are counted toward developed sites, and examples include headquarters, ranger stations, patrol cabins, park entrances, federal employee housing, and other facilities supporting government operations. In contrast to developed or administrative sites, “dispersed sites” are those not associated with a developed site, such as a front-country campground. These sites are typically characterized as having no permanent agency-constructed features, are temporary in nature, have minimal to no site modifications, have informal spacing, and possibly include primitive road access. Dispersed sites are not counted toward developed sites. Developed sites on public lands are currently inventoried and tracked in GIS databases. As of 1998, there were 593 developed sites on public land within the PCA (U.S. Fish and Wildlife Service 2016, Appendix E). As of 2014, the number of developed sites on public lands had decreased to 578 (Greater Yellowstone Area Grizzly Bear Habitat Modeling Team 2015, p. 90).

The primary concern related to developed sites is direct mortality from bear-human encounters and unsecured attractants. Secondary concerns include temporary or permanent habitat loss and displacement due to increased length of time of human use and increased human disturbance to surrounding areas. In areas of suitable habitat inside the PCA, the National Park Service and the Forest Service enforce food storage rules aimed at decreasing grizzly bear access to human foods (U.S. Fish and Wildlife Service 2016, Chapter 1). These regulations will continue to be enforced and are in effect for nearly all currently occupied grizzly bear habitat within the GYE grizzly bear DPS boundaries (U.S. Fish and Wildlife Service 2016, Chapter 1). In conclusion, because the National Parks and National Forests within the PCA will continue to manage developed sites at 1998 levels within each bear management subunit and because food storage rules will be enforced on these public lands, we do not foresee that the existing number of, nor an increase in the number of, developed sites inside the PCA will pose a threat to the GYE grizzly bear DPS now, or in the future.

Livestock Allotments:

When grizzly bears were listed in 1975, the Service identified “. . . livestock use of surrounding national forests” as detrimental to grizzly bears “. . . unless management measures favoring the species are enacted” (40 FR 31734; July 28, 1975). Impacts to grizzly bears from livestock operations potentially include: (1) Direct mortality from control actions resulting from livestock depredation; (2) direct mortality due to control actions resulting from grizzly bear habituation and/or learned use of bear attractants such as livestock carcasses and feed; (3) increased chances of a grizzly bear livestock conflict; (4) displacement due to livestock or related management activity; and (5) direct competition for preferred forage species.

Approximately 14 percent (45/311) of all human-caused grizzly bear mortalities in the GYE between 2002 and 2014 were due to management removal actions associated with livestock depredations. This human-caused mortality is the main impact to grizzly bears in the GYE associated with livestock. Increased chances of grizzly bear conflict related to livestock have been minimized through requirements to securely store and/or promptly remove attractants associated with livestock operations (

e.g.,

livestock carcasses, livestock feed, etc.). The effects of displacement and direct competition with livestock for forage are considered negligible to grizzly bear population dynamics because even with direct grizzly bear mortality, current levels of livestock allotments have not precluded grizzly bear population growth and expansion.

The 2007 Conservation Strategy and Forest Service Record of Decision implementing their forest plan amendments (USDA Forest Service 2006

b,

entire) established habitat standards regarding livestock allotments. The number of active livestock allotments, total acres affected, and permitted sheep animal months within the PCA will not increase above 1998 levels (USDA Forest Service 2006

b,

p. 5; U.S. Fish and Wildlife Service 2016, Chapter 3). Due to the higher prevalence of grizzly bear conflicts associated with sheep grazing, existing sheep allotments will be phased out as the opportunity arises with willing permittees (USDA Forest Service 2006

b,

p. 6; U.S. Fish and Wildlife Service 2016, Chapter 3).

A total of 106 livestock allotments existed inside the PCA in 1998. Of these allotments, there were 72 active and 13 vacant cattle allotments and 11 active and 10 vacant sheep allotments, with a total of 23,090 animal months (U.S. Fish and Wildlife Service 2016, Appendix E). Sheep animal months are calculated by multiplying the permitted number of animals by the permitted number of months. Any use of vacant allotments will only be permitted if the number and net acreage of allotments inside the PCA does not increase above the 1998 baseline. Since 1998, the Caribou-Targhee National Forest has closed six sheep allotments within the PCA, while the Shoshone National Forest has closed two sheep allotments and the Gallatin National Forest has closed four (Greater Yellowstone Area Grizzly Bear Habitat Modeling Team, p. 86). This has resulted in a reduction of 21,120 sheep animal months, a 91 percent reduction,

from the total calculated for 1998 within the PCA, and is a testament to the commitment land management agencies have to the ongoing success of the grizzly bear population in the GYE. As of 2014, there is only one active sheep allotment within the PCA, on the Caribou-Targhee National Forest. The mandatory restriction on creating new livestock allotments and the voluntary phasing out of livestock allotments with recurring conflicts further ensure that the PCA will continue to function as source habitat. Because there will continue to be no net increase in cattle or sheep allotments allowed on public lands inside the PCA, we do not expect that livestock allotments inside the PCA will constitute a threat to the GYE grizzly bear DPS now, or in the future.

Mineral and Energy Development:

Management of oil, gas, and mining are tracked as part of the developed site standard (U.S. Fish and Wildlife Service 2016, Chapter 3). There were no active oil and gas leases inside the PCA as of 1998 (USDA Forest Service 2006

a,

p. 209). Based on Forest Plan direction, there are approximately 243 sq km (94 sq mi) of secure habitat that could allow surface occupancy for oil and gas projects within the PCA (USDA Forest Service 2006

a,

figures 48 and 96). This comprises less than 4 percent of all suitable habitat within the PCA. Additionally, 1,354 preexisting mining claims were located in 10 of the subunits inside the PCA (U.S. Fish and Wildlife Service 2016, Appendix E), but only 28 of these mining claims had operating plans. These operating plans are included in the 1998 developed site baseline. Under the conditions of the draft 2016 Conservation Strategy, any new oil, gas or mineral project will be approved only if it conforms to secure habitat and developed site standards (U.S. Fish and Wildlife Service 1993, p. 5-6; U.S. Fish and Wildlife Service 2016, Chapter 3). For instance, any oil, gas or mineral project that reduces the amount of secure habitat permanently will have to provide replacement secure habitat of similar habitat quality (based on our scientific understanding of grizzly bear habitat), and any change in developed sites will require mitigation equivalent to the type and extent of the impact, and such mitigation must be in place before project initiation or be provided concurrently with project development as an integral part of the project plan (U.S. Fish and Wildlife Service 2016, chapter 3). For projects that temporarily change the amount of secure habitat, only one project is allowed in any subunit at any time (U.S. Fish and Wildlife Service 2016, chapter 3). Mitigation of any project will occur within the same subunit and will be proportional to the type and extent of the project (U.S. Fish and Wildlife Service 2016, chapter 3). In conclusion, because any new mineral or energy development will continue to be approved only if it conforms to the secure habitat and developed site standards set forth in the draft 2016 Conservation Strategy, we do not expect that such development inside the PCA will constitute a threat to the GYE grizzly bear DPS now, or in the future.

Recreation:

At least 3 million people visit and recreate in the National Parks and National Forests of the GYE annually (USDA Forest Service 2006

a,

pp. 176, 184; Cain 2014, p. 46; Gunther 2014, p. 47). Based on past trends, visitation and recreation are expected to increase in the future. For instance, Yellowstone National Park has shown an approximate 15 percent increase in the number of people visiting each decade since the 1930s (USDA Forest Service 2006

a,

p. 183); however, the number of people recreating in the backcountry there has remained relatively constant from the 1970s through 2010s (Gunther 2014, p. 47). The concern related to increased recreation is that it may increase the probability of grizzly bear-human encounters, with subsequent increases in human-caused mortality (Mattson

et al.

1996, p. 1014).

Recreation in the GYE can be divided into six basic categories based on season of use (winter or all other seasons), mode of access (motorized or non-motorized), and level of development (developed or dispersed) (USDA Forest Service 2006

a,

p. 187). Inside the PCA, the vast majority of lands available for recreation are accessible through non-motorized travel only (USDA Forest Service 2006

a,

p. 179). Motorized recreation during the summer, spring, and fall inside the PCA will be limited to existing roads as per the standards in the draft 2016 Conservation Strategy that restrict increases in roads or motorized trails. Similarly, recreation at developed sites such as lodges, downhill ski areas, and campgrounds will be limited by the developed sites habitat standard described in the draft 2016 Conservation Strategy. The number and capacity of existing developed sites on public lands will not increase once delisting occurs. For a more complete discussion of projected increases in recreation in the GYE National Forests, see the Final Environmental Impact Statement for the Forest Plan Amendment for Grizzly Bear Habitat Conservation for the GYE National Forests (USDA Forest Service 2006

a,

pp. 176-189).

This potential stressor on the GYE grizzly bear population would exist regardless of listed status and will be addressed in the same way whether this population is listed or delisted, through ongoing information and education campaigns. These outreach efforts are an important contributing factor to successful grizzly bear conservation and would continue under the 2016 Conservation Strategy. In conclusion, because the few motorized access routes inside the PCA will not increase, because the number and capacity of developed sites on public lands within the PCA will not increase, and because the National Parks and National Forests within the PCA will continue to educate visitors on its lands about how to recreate safely in bear country and avoid grizzly bear-human conflicts, we do not expect that the current level of recreation, nor increases in recreation, will constitute a threat to the GYE grizzly bear DPS now, or in the future.

Snowmobiling:

Snowmobiling has the potential to disturb bears while in their dens and after emergence from their dens in the spring. Because grizzly bears are easily awakened in the den (Schwartz

et al.

2003

b,

p. 567) and have been documented abandoning den sites after seismic disturbance (Reynolds

et al.

1986, p. 174), the potential impact from snowmobiling should be considered. We found no studies in the peer-reviewed literature documenting the effects of snowmobile use on any denning bear species, and the information that is available is anecdotal in nature (U.S. Fish and Wildlife Service 2002, entire; Hegg

et al.

2010, entire).

Disturbance in the den could result in increased energetic costs (increased activity and heart rate inside the den) and possibly den abandonment, which, in theory, could ultimately lead to a decline in physical condition of the individual or even cub mortality (Swenson

et al.

1997, p. 37; Graves and Reams 2001, p. 41). Although the potential for this type of disturbance while in the den certainly exists, Reynolds

et al.

(1986, p. 174) found that grizzly bears denning within 1.4 to 1.6 km (0.9 to 1.0 mi) of active seismic exploration and detonations moved around inside their dens but did not leave them. Harding and Nagy (1980, p. 278) documented two instances of den abandonment during fossil fuel extraction operations. One bear abandoned its den when a seismic vehicle drove directly over the den (Harding and Nagy 1980, p. 278). The other bear abandoned its den when a

gravel mining operation literally destroyed the den (Harding and Nagy 1980, p. 278). Reynolds

et al.

(1986, entire) also examined the effects of tracked vehicles and tractors pulling sledges. In 1978, there was a route for tractors and tracked vehicles within 100 m (328 ft) of a den inhabited by a female with three yearlings. This family group did not abandon their den at any point (Reynolds

et al.

1986, p. 174). Reynolds

et al.

(1986, p. 174) documented one instance of possible den abandonment due to detonations for seismic testing within 200 m of a den (Reynolds

et al.

1986, p. 174). This bear was not marked, but an empty den was reported by seismic crews.

Swenson

et al.

(1997, entire) monitored 13 different grizzly bears for at least 5 winters each and documented 18 instances of den abandonment, 12 of which were related to human activities. Four of these instances were hunting related (

i.e.,

gunshots fired within 100 m (328 ft) of the den), two occurred after “forestry activity

at

the den site,” one had moose and dog tracks within 10 m (33 ft) of a den, one had dog tracks

at

the den site, one had ski tracks within 80 to 90 m (262 to 295 ft) from a den, one had an excavation machine working within 75 m (246 ft) of a den, and two were categorized as “human related” without further details (Swenson

et al.

1997, p. 37). Swenson

et al.

(1997) found that most den abandonment (72 percent) occurred early in the season before pregnant females give birth. However, there still may be a reproductive cost of these early den abandonments: 60 percent (sample size of 5) of female bears that abandoned a den site before giving birth lost at least one cub whereas only 6 percent (sample size of 36) of pregnant females that did not abandon their dens lost a cub in or near their den (Swenson

et al.

1997, p. 37). In the GYE, the one documented observation of snowmobile use at a known den site found the bear did not abandon its den, even though snowmobiles were operating directly on top of it (Hegg

et al.

2010, p. 26). This, however, is only an anecdotal observation because it is based on a sample size of one. We found no records of litter abandonment by grizzly bears in the lower 48 States due to snowmobiling activity. Additionally, monitoring of den occupancy for 3 years on the Gallatin National Forest in Montana did not document any den abandonment (Gallatin National Forest 2006, entire).

In summary, the available data about the potential for disturbance while denning and den abandonment from nearby snowmobile use are extrapolated from studies examining the impacts of other human activities and are identified as “anecdotal” in nature (Swenson

et al.

1997, p. 37) with sample sizes so small they cannot be legitimately applied to assess population-level impacts (in their entirety: Harding and Nagy 1980; Reynolds

et al.

1986; Hegg

et al.

2010). Because there are no data or information suggesting snowmobile use in the GYE is negatively affecting grizzly bear population, or even individual bears, we determine that snowmobiling does not constitute a threat to the GYE grizzly bear DPS now, or in the future. Yet, because the potential for disturbance and impacts to reproductive success exists, monitoring will continue to support adaptive management decisions about snowmobile use in areas where disturbance is documented or likely to occur.

Vegetation Management:

Vegetation management occurs throughout the GYE on lands managed by the Forest Service and National Park Service. Vegetation management projects typically include timber harvest, thinning, prescribed fire, and salvage of burned, diseased, or insect-infested stands. If not implemented properly, vegetation management programs can negatively affect grizzly bears by: (1) Removing hiding cover; (2) disturbing or displacing bears from habitat during the logging period; (3) increasing grizzly bear-human conflicts or mortalities as a result of unsecured attractants; and (4) increasing mortality risk or displacement due to new roads into previously roadless areas and/or increased vehicular use on existing restricted roads, especially if roads remain open to the public after vegetation management is complete.

Conversely, vegetation management may result in positive effects on grizzly bear habitat once the project is complete, provided key habitats such as riparian areas and known food production areas are maintained or enhanced. For instance, tree removal for thinning or timber harvest and prescribed burning can result in localized increases in bear foods through increased growth of grasses, forbs, and berry-producing shrubs (Zager

et al.

1983, p. 124; Kerns

et al.

2004, p. 675). Vegetation management may also benefit grizzly bear habitat by controlling undesirable invasive species, improving riparian management, and limiting livestock grazing in important food production areas.

Changes in the distribution, quantity, and quality of cover are not necessarily detrimental to grizzly bears as long as they are coordinated on a BMU or subunit scale to ensure that grizzly bear needs are addressed throughout the various projects occurring on multiple jurisdictions at any given time. Although there are known, usually temporary, impacts to individual bears from timber management activities, these impacts have been adequately mitigated using the Interagency Grizzly Bear Guidelines in place since 1986, and will continue to be managed at levels acceptable to the grizzly bear population under the 2016 Conservation Strategy. Therefore, we do not expect that vegetation management inside the PCA will constitute a threat to the GYE grizzly bear DPS now, or in the future.

Climate Change:

The effects of climate change may result in a number of changes to grizzly bear habitat, including a reduction in snowpack levels, shifts in denning times, shifts in the abundance and distribution of some natural food sources, and changes in fire regimes. Most grizzly bear biologists in the United States and Canada do not expect habitat changes predicted under climate change scenarios to directly threaten grizzly bears (Servheen and Cross 2010, p. 4). These effects may even make habitat more suitable and food sources more abundant. However, these ecological changes may also affect the timing and frequency of grizzly bear-human interactions and conflicts (Servheen and Cross 2010, p. 4) and are discussed below under Factor E (

Other Natural or Manmade Factors Affecting Its Continued Existence

).

Habitat Fragmentation:

The GYE grizzly bear population is currently a contiguous population across its range, and there are no data to indicate habitat fragmentation within this population is occurring. Although currently not occurring, habitat fragmentation can cause loss of connectivity and increase human-caused mortalities, and thus is a potential threat to grizzly bears. To prevent habitat fragmentation and degradation, the evaluation of all road construction projects in suitable habitat on Federal lands throughout the GYE DMA will continue to include the impacts of the project on grizzly bear habitat connectivity. This evaluation would go through an open and public planning process (U.S. Fish and Wildlife Service 2007

a,

pp. 38-41; U.S. Fish and Wildlife Service 2016, Chapter 3). By identifying areas used by grizzly bears, officials can mitigate potential impacts from road construction both during and after a project. Federal agencies will continue to identify important crossing areas by collecting information about known bear crossings, bear sightings, ungulate road

mortality data, bear home range analyses, and locations of game trails. Potential advantages of this data collection requirement include reduction of grizzly bear mortality due to vehicle collisions, access to seasonal habitats, maintenance of traditional d

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