# Endangered and Threatened Wildlife and Plants; Threatened Status With Section 4(d) Rule for the Dolphin and Union Caribou and 12-Month Finding for the Peary Caribou

> Briefs, arguments, decisions, and more.

URL: https://www.frixlaw.com/law-library/documents/fr%3A2021-18098

## Record

- **Collection:** Federal Register
- **Document type:** Proposed Rule
- **Published:** August 31, 2021
- **Citation:** 86 FR 48619

## Text

DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[Docket No. FWS-HQ-ES-2019-0014; 4500030113]
RIN 1018-BD03
Endangered and Threatened Wildlife and Plants; Threatened Status With Section 4(d) Rule for the Dolphin and Union Caribou and 12-Month Finding for the Peary Caribou

AGENCY:

Fish and Wildlife Service, Interior.

ACTION:

Proposed rule; 12-month finding.

SUMMARY:

We, the U.S. Fish and Wildlife Service, announce a 12-month finding on a petition to list the Peary caribou (
Rangifer tarandus pearyi
) (a caribou subspecies) and the Dolphin and Union caribou (
Rangifer tarandus groenlandicus x peary
) as endangered or threatened subspecies under the Endangered Species Act of 1973, as amended (Act). Both Peary caribou and Dolphin and Union caribou are native only to Canada. After a review of the best available scientific and commercial information, we find that it is not warranted at this time to add the Peary caribou to the List of Endangered and Threatened Wildlife. We find that listing the Dolphin and Union caribou as a Distinct Population Segment (DPS) of the barren-ground caribou subspecies (
Rangifer tarandus groenlandicus
) is warranted. Accordingly, we propose to list this DPS with a rule issued under section 4(d) of the Act (“4(d) rule”). To ensure that subsequent rulemaking resulting from this proposed rule is as accurate and effective as possible, we are soliciting information from the public, other governmental agencies, the Government of Canada and its provincial governments, the scientific community, industry, and any other interested parties.

DATES:

We will accept comments received or postmarked on or before November 1, 2021. 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. We must receive requests for public hearings, in writing, at the address shown in
FOR FURTHER INFORMATION CONTACT
by October 15, 2021

ADDRESSES:

You may submit comments by one of the following methods:

(1)
Electronically:
Go to the Federal eRulemaking Portal:
http://www.regulations.gov.
In the Search box, enter the docket number or RIN for this rulemaking (presented above in the document headings). For best results, do not copy and paste either number; instead, type the docket number or RIN into the Search box using hyphens. Then, click on the Search button. On the resulting page, in the panel on the left side of the screen, under the Document Type heading, check the Proposed Rule box to locate this document. You may submit a comment by clicking on “Comment.”

(2)
By hard copy:
Submit by U.S. mail to: Public Comments Processing, Attn: FWS-HQ-ES-2019-0014; U.S. Fish and Wildlife Service; MS: JAO/3W; 5275 Leesburg Pike, Falls Church, VA 22041-3803.

We request that you send 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
Public Comments,
below, for more information).

FOR FURTHER INFORMATION CONTACT:

Elizabeth Maclin, Branch of Delisting and Foreign Species, Ecological Services Program, U.S. Fish and Wildlife Service, 5275 Leesburg Pike, MS: ES, Falls Church, VA 22041; telephone 703-358-2646. If you use a telecommunications device for the deaf, call the Federal Relay Service at 800-877-8339.

SUPPLEMENTARY INFORMATION:

Executive Summary

Why we need to publish a rule.
Under the Endangered Species Act of 1973, as amended (“Act,” 16 U.S.C. 1531
et seq.
), if we determine that a species warrants listing as an endangered or threatened species, we are required to promptly publish a proposal in the
Federal Register
and make a determination on our proposal within 1 year.

What this document does.
We find that listing the Peary caribou subspecies is not warranted, and we propose to list the Dolphin and Union caribou DPS as a threatened species with a rule under section 4(d) of the Act.

The basis for our action.
Under the Act, we may determine that a species is an endangered or threatened species because of any of five factors, alone or in combination: (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 have determined that the Peary caribou is not in danger of extinction or likely to become so in the foreseeable future throughout all or a significant portion of its range. We have determined that the Dolphin and Union caribou DPS is likely to become endangered in the foreseeable future throughout all of its range, meeting the definition of a threatened species.

Both caribou subspecies exist in harsh environments to which they have adapted over millennia. These harsh environmental conditions combined with the fact that they live on islands from which they make seasonal migrations across sea ice in order to find adequate nutrition combine to exert pressure on both the Peary caribou subspecies and Dolphin and Union caribou DPS. The major threats that impacted both the Peary caribou and Dolphin and Union caribou are the cumulative effects of climate change and other changes brought about by climate change. While these two subspecies face similar threats, the magnitude of threats they face is different between the two subspecies, including with respect to the following threats:

• Long-term decline in sea ice;

• Increase in icing events on land;

• Hunting;

• Outbreaks of parasites or disease;

• Disturbance due to development, oil and gas exploration, and shipping; and

• Increases in shipping traffic.

The Peary caribou is found farther to the north of the Canadian Arctic while the Dolphin and Union caribou is located to the south. Certain activities, such as shipping and oil and gas exploration, are more concentrated in the southern portion of the Canadian Arctic, thus affecting the Dolphin and Union caribou more strongly than the Peary caribou. Furthermore, models of sea-ice loss projected that the decline in sea ice in the lower Canadian Arctic will occur earlier and faster than the high Arctic. The differences in degree of threats result in the population trends for these two subspecies moving in opposite directions. Although the Peary caribou has experienced wide fluctuation in its population, the subspecies has experienced an increase of about 150 percent within the past two decades (COSEWIC 2015, pp. 42-43). In contrast, after reaching a high in 1997, the Dolphin and Union caribou population has steadily declined.

We are also proposing a section 4(d) rule.
When we list a species as threatened, section 4(d) of the Act (16 U.S.C. 1533(d)) allows us to issue regulations that are necessary and advisable to provide for the conservation of the species. Accordingly, we are proposing a 4(d) rule for the Dolphin and Union caribou that would, among other things, prohibit import, export, interstate or foreign commerce in the course of commercial activity, sale or offer for sale, or to attempt to engage in any such conduct. Exceptions are provided for import of personal sport-hunted trophies legally hunted in and exported from Canada. We may issue permits to carry out otherwise prohibited activities, including those described above, involving threatened wildlife under certain circumstances, such as for scientific purposes, or the enhancement of propagation or survival of the subspecies in the wild.

Peer review.
In accordance with our joint policy on peer review published in the
Federal Register
on July 1, 1994 (59 FR 34270), and our August 22, 2016, memorandum updating and clarifying the role of peer review of listing actions under the Act, we solicited the expert opinion of five appropriate and independent specialists for peer review of the Species Status Assessment that provides the biological basis for this proposed listing determination. The purpose of peer review is to ensure that our listing determinations are based on scientifically sound data, assumptions, and analyses. Their comments and suggestions can be found at
https://www.fws.gov/endangered/improving_ESA/peer_review_process.html.

Because we will consider all comments and information received during the comment period, our final determination may differ from this proposal. After considering comments and information we receive, we may conclude that the species is endangered instead of threatened, or we may conclude that the species does not warrant listing as either an endangered species or a threatened species. Such final decisions would be a logical outgrowth of this proposal, as long as we: (1) Base the decisions on the best scientific and commercial data available after considering all of the relevant factors; (2) do not rely on factors Congress has not intended us to consider; and (3) articulate a rational connection between the facts found and the conclusions made, including why we changed our conclusion.

Information Requested

We intend that any final action resulting from this proposed rule will be based on the best scientific and commercial data available and be as accurate and as effective as possible. Therefore, we request comments or information from other concerned governmental agencies, including Canadian national and provincial governments, local indigenous people of Canada, the scientific community, industry, and any other interested parties concerning this proposed rule. We particularly seek comments concerning:

(1) The species' biology, range, and population trends, including:

(a) Biological or ecological requirements of the species, including habitat requirements for feeding, breeding, and sheltering;

(b) Genetics and taxonomy of the two caribou entities; specifically, any genetic information that would help inform the taxonomic status of the Dolphin and Union caribou;

(c) Historical and current range including distribution patterns, particularly regarding their seasonal migrations;

(d) Historical and current population levels, and current and projected population trends; and

(e) Past and ongoing conservation measures for these species and/or their habitat.

(2) Factors that may affect the continued existence of the species, which may include habitat destruction, modification, or curtailment, overutilization, disease, predation, the inadequacy of existing regulatory mechanisms, or other natural or manmade factors.

(3) Biological, commercial, trade, or other relevant data concerning any threats (or lack thereof) to this species and existing regulations that may be addressing those threats.

(4) Additional information concerning the historical and current status, range, distribution, and population size of this species, including the locations of any additional populations of this species.

(5) Information on regulations that are necessary and advisable to provide for the conservation of the Dolphin and Union caribou and that the Service can consider in developing a 4(d) rule for the species, particularly, information concerning the extent to which the 4(d) rule should prohibit any act prohibited by section 9(a)(1) or whether any exceptions should be provided from the prohibitions in the 4(d) rule.

Please include sufficient information with your submission (such as scientific journal articles or other publications) to allow us to verify any scientific or commercial information you include.

Please note that submissions merely stating support for, or opposition to, the action under consideration without providing supporting information, although noted, will not be considered

in making a determination, as section 4(b)(1)(A) of the Act directs that determinations as to whether any species is an endangered or a threatened species must be made “solely on the basis of the best scientific and commercial data available.”

You may submit your comments and materials concerning this proposed rule by one of the methods listed in
ADDRESSES
. We request that you send comments only by the methods described in
ADDRESSES
.

If you submit information via
http://www.regulations.gov,
your entire submission—including any personal identifying information—will be posted on the website. If your submission is made via a hardcopy that includes personal identifying information, 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. We will post all hardcopy submissions on
http://www.regulations.gov.

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
.

Public Hearing

Section 4(b)(5) of the Act provides for one or more public hearings on this proposal, if requested. Requests must be received by the date listed above in
DATES
. Such requests must be sent to the address shown in
FOR FURTHER INFORMATION CONTACT
. If requested, we will schedule any such public hearings, and announce the dates, times, and places of those hearings, as well as how to obtain reasonable accommodations, in the
Federal Register
at least 15 days before the hearing. For the immediate future, we will provide these public hearings using webinars that will be announced on the Service's website, in addition to the
Federal Register
. The use of these virtual public hearings is consistent with our regulation at 50 CFR 424.16(c)(3).

Previous Federal Actions

On September 15, 2009, we received a petition dated the same day from the International Fund for Animal Welfare (hereafter referred to as petitioner) requesting that two subspecies of caribou (
Rangifer tarandus
) be listed as endangered or threatened under the Act. These two subspecies are the Peary caribou (
R. t. pearyi
) and the Dolphin and Union caribou (
R. t. groenlandicus x pearyi
). On April 5, 2011, we published a “positive” 90-day finding that the petition presented substantial scientific or commercial information indicating that listing both the Peary caribou subspecies and Dolphin and Union caribou subspecies as endangered or threatened may be warranted (76 FR 18701), and we initiated a status review of these two subspecies.

This document summarizes the status reviews for these two species under section 4(b)(3)(B) of the Act and publishes our findings. The actual assessments of each species (also called a species report) are available at
http://www.regulations.gov
in Docket No. FWS-HQ-ES-2019-0014. This document also includes the proposed rule to list the Dolphin and Union caribou Distinct Population Segment (DPS) of the barren-ground caribou subspecies as a threatened species with a 4(d) rule.

Supporting Documents

A species report was prepared for each species. The species reports represent compilations of the best scientific and commercial data available concerning the status of each species, including the impacts of past, present, and future factors (both negative and beneficial) affecting the species. The Service sent the species reports to five independent peer reviewers and received five responses.

I. Proposed Listing Determination—Peary Caribou

Background

Description

Peary caribou have relatively large, short hooves; square muzzles; short, rounded ears; and dense pale fur made of hollow hairs. Their fur is long and silky white in early winter and changes to a light brown/tan in the spring. In the summer, the coat is slate with a white stomach; legs are white with the flank having a pronounced frontal stripe. Both male and female caribou grow narrowly spreading antlers, although antlers may be absent in some females. Antler velvet is grey, and the antlers are bone-colored (COSEWIC 2004, pp. 9-10). Peary caribou have smaller bodies with shorter legs and faces when compared to the barren-ground caribou (
Rangifer tarandus groenlandicu
s) on the North American mainland (COSEWIC 2015, p. 5).

Taxonomy

All caribou and reindeer worldwide are considered to be the same species (
Rangifer tarandus
) in the Order Artiodactyla (even-toed ungulates) and Family Cervidae (deer) (Integrated Taxonomic Information System (ITIS) 2013, unpaginated; Mountain Caribou Science Team 2005, p. 1; Smithsonian National Museum of Natural History 2013, npn; COSEWIC 2011, p. 11). Although caribou and reindeer are referred to by different names based on geography and whether or not they are bred in captivity, they are able to interbreed and produce offspring (COSEWIC 2002, p. 9; Hummel and Ray, 2008, p. 31). In Europe, the common name for
Rangifer tarandus
is reindeer. In North America, the common name for the species is caribou; only the individuals bred in captivity are called reindeer (Cichowski et al. 2004, p. 224). For consistency, the term caribou will be used to refer to the species
Rangifer tarandus
in this document. According to the American Society of Mammologists' checklist of mammal species of the world and ITIS, 14 subspecies of caribou are currently recognized worldwide, including the subspecies Peary caribou,
Rangifer tarandus pearyi
(ITIS 2017, unpaginated).

Peary caribou were first taxonomically described in 1902. The first widely accepted classification below the species level of caribou,
Rangifer tarandus,
in North America was in 1961 (COSEWIC 2015, p. 5; COSEWIC 2011, pp. 11-12; Shackleton 2010, p. 3; Banfield 1961, entire).

Since the 1960s, much has been learned about caribou ecology, distribution, and genetics that has revealed substantial diversity within the initial 1961 subspecies classifications (Miller et al. 2007, p. 16). Many have proposed alternative classifications to account for variability within and among the various subspecies of caribou. Populations were described with terms such as “ecotypes” based on migration patterns and calving strategies, and adaptations to a certain set of environmental conditions (Bergerud 1996, entire, as cited in COSEWIC 2011, p. 13). This later classification has caused confusion because there is no universally accepted list of caribou ecotypes or criteria to distinguish them (COSEWIC 2011, pp. 12-13).

In 1979, an independent advisory committee of wildlife experts, Committee on the Status of Endangered Wildlife in Canada (COSEWIC), assessed the status of Peary caribou,
Rangifer tarandus pearyi,
and what is now known as the Dolphin and Union caribou as a single subspecies for purposes of Canada's Species at Risk Act (SARA). Following the assessment, COSEWIC assigned the species a status of threatened under SARA. A threatened species under SARA is a wildlife species that is likely to become endangered if nothing is done to reverse

the factors leading to its extirpation or extinction (COSEWIC 2016, pp. 85-86). In 1991, this entity was split up and assessed as three separate populations: Banks Island (Endangered), High Arctic (Endangered), and Low Arctic (Threatened). In May 2004, these three populations were deactivated and combined into a single entity, the Peary caribou. The Peary caribou was then reassessed and given the status of endangered (COSEWIC 2016, p. 86).

In 2011, COSEWIC prepared to conduct a reassessment of all caribou in Canada; as a result, they published a document detailing the “designatable units” (DU) of caribou, which were geographically based areas created for management purposes. Peary caribou populations are considered one of the DUs, and as such, a review of the current science on the species was conducted. In this report, COSEWIC recognized Peary caribou as a subspecies (
R. t. pearyi)
distinct from the barren-ground caribou (
R. t. groenlandicus)
and distinct from the Dolphin and Union caribou subpopulation. Additionally, the report states that Peary caribou have “no clear morphological differentiation within [the Peary populations] to support any subdivision” (Gunn 2009, as cited in COSEWIC 2011, p. 23).

A new status report published in 2015 confirmed Peary caribou status as a subspecies (COSEWIC 2015, p. 13). At this time, both the northern and southern Peary caribou populations are considered the same subspecies (Taylor et al. 2012, p. 36746; Jenkins et al. 2011, p. 27; McFarlane et al. 2014, as cited in COSEWIC 2015, p. 6). We accept the characterization of the Peary caribou as a subspecies based on genotypic and phenotypic evidence, and we consider all Peary caribou to be one subspecies distinct from the barren-ground caribou and distinct from the Dolphin and Union caribou (COSEWIC 2015, p. 13; Peterson et al. 2010, p. 698; COSEWIC 2004, pp. 8, 11-17; McFarlane et al. 2009, pp. 105, 120-126).

Life History

Peary caribou have an average lifespan of 13-15 years, similar to other types of caribou. Males typically reach breeding age at around 4 years and females (cows) between 2-3 years (COSEWIC 2004, p. 28). Approximately 80 percent of females will calve annually; females will generally reproduce between the ages of 2 and 13 years and males between 4 and 13 years (Gunn et al. 2000, as cited in COSEWIC 2004, p. 28). The subspecies resides at a latitude that occurs at the edge of suitable areas for plant growth. This condition necessitates a mobile feeding strategy where the Peary caribou migrate from island to island to maximize forage (Miller and Barry 2009, pp. 179, 185). The annual rut (mating season of caribou) usually occurs in late autumn, and calving occurs in late spring with variation depending on the latitude and environmental conditions (COSEWIC 2011, p. 11; Gates et al. 1986, pp. 216-221). Caribou cows are known to be loyal to their calving grounds (COSEWIC 2004, p. 30). In free-ranging caribou populations, the proportion of caribou averages 40 males to 60 females (Miller et al. 2007, p. 25).

The fecundity (the reproductive rate of an organism) or calf production (the term often used in caribou research) and recruitment (when calves survive their first winter and become part of a population) of Peary caribou are highly dependent on the female's physical condition, specifically on fat reserves (Cameron et al. 1992, p. 480). The nutritional condition of the female is dependent on the prevailing environmental conditions; as a result, there is high variability in annual pregnancy rate, calf production, and calf recruitment. Depending on the environmental factors and the physical conditions of females, pregnancy rates can vary from 0 percent to 100 percent. In severe winters, recruitment of calves can drop to 0 percent (COSEWIC 2004, p. 28). Under favorable conditions, roughly 50 percent of calves survive their first winter (Miller et al. 2007, p. 25).

Diet and Nutrition

Peary caribou calving is closely related to plant phenology (timing of plant blooming based on daylight and temperature). Seasonal feeding is critical for various life stages such as lactation and growth during the spring, increasing fat reserves during the summer, and surviving during the winter (COSEWIC 2004, pp. 28-35). Summer and winter forage varies based on availability, but Peary caribou prefer willow
(Salix arctica),
sedges
(Carex
species), purple saxifrage
(Saxifraga oppositifolia),
grasses and forbs, and lichens (COSEWIC 2004, p. 23).

The diet of the Peary caribou varies depending on the season and availability of vegetation (Miller and Barry 2009, pp. 184-185; COSEWIC 2004, p. 34). Generally, caribou acquire most of their dietary protein during the summer and consume higher energy plants in the winter when their energy demands are higher (Joly et al 2010, p. 322). Additionally, willow has been found to be an important source of nutrition, especially in the summer, as caribou on a high willow diet seem to maintain a better reproductive condition (Parker 1978, as cited in COSEWIC 2004, pp. 32-33). Lichens are generally understood to contribute a relatively low proportion (~8 percent) of winter and summer diet, when compared to other caribou subspecies, for the Peary caribou on Bathurst, Melville, and Prince Patrick Islands (COSEWIC 2015, p. 22; Miller and Barry 2009, p. 184). While lichens provide easily digestible carbohydrates, they have fairly low protein content in comparison with the green foliage of vascular plants (Joly et al. 2010, p. 322; Chen et al. 2009a, pp. 8-9).

Under ideal conditions, caribou forage by pushing snow off vegetation with their noses, but when snowpack is deeper, they will dig small craters in the snow to reach the plants (COSEWIC 2004, p. 35). However, snow conditions can limit the accessibility of the vegetation. Early winter snow, especially in combination with rain in late September or early October, can cause icing conditions, which may prevent caribou from accessing the vegetation (COSEWIC 2004, pp. 33-34). Snowfall within the range of the Peary caribou varies, and the amount of snow is determined by several variables, such as the terrain, wind speed and direction, and air and ground temperatures (Sturm 2003, as cited in Maher 2012, p. 84). As a result, during the winter, caribou tend to forage in drier, more exposed areas, which have less snow or softer, less crusted snow.

Range

The Peary caribou is endemic to the Canadian Arctic Archipelago in northeastern Canada. The islands are located in the Territories of Nunavut and the Northwest Territories (NWT) in Canada in an ecozone described as the “high arctic”

The terrestrial range of Peary caribou is vast, with its size being roughly 540,000 square kilometers (km
2
) (208,495 mi
2
) (Jenkins et al. 2011, p. 1). The subspecies' range extends from Queen Elizabeth Islands (QEI) in the north, Banks Island in the west, Somerset Island in the east, and the Boothia Peninsula in the southeast (Jenkins et al. 2011, p. 1; see map 1). In Nunavut, the subspecies' range includes approximately 25 large islands and 40 small islands, the majority of which are uninhabited by humans (Jenkins et al. 2011, p. 15). In the NWT, this subspecies occurs in an area consisting of over 237,022 km
2
(91,514 mi
2
) (Governments of NWT and Nunavut 2011, p. 6). The Queen Elizabeth Archipelago consists of 35 islands that

are over 129 km
2
(49.8 mi
2
) in size (Hummel et al. 2008, p. 216).

Population Estimates and Migration

Due to ambiguity in taxonomy, older population surveys from the early 20th century may not be accurate in terms of which subspecies was documented in various island populations.

In Nunavut, a 2011 survey of Peary caribou reported the most current population estimates (Jenkins et al. 2011, p. ii; Jenkins 2008, 17 pp.). In the NWT, an aerial survey of Peary caribou was conducted in 2012 (Davison and Williams 2016, p. 3). For detailed information about the most recent surveys of Peary caribou, we refer readers to both documents and our species report, which are available at
www.regulations.gov,
Docket number FWS-HQ-ES-2019-0014. In this finding, we summarize this information.

Peary caribous occur in small groups consisting of three to five individuals; as a result, these caribou are referred to at the scale of `subpopulations' or `clusters' as opposed to herds, as seen in barren-ground caribou (Davison 2017, pers. comm.; Jenkins et al. 2011, p. 11). The size of these clusters will vary depending on the season; subpopulations will increase slightly prior to calving, then stabilize or decrease during calving, and increase in the “post-calving aggregations” as they migrate inland from coastal areas (COSEWIC 2004, p. 35). Peary caribou populations are often described as “island group” subpopulations as they are associated with a set of islands used regularly during their seasonal migrations (Jenkins et al. 2011, p. xiii; Gunn et al. 2011, pp. 41-44). That said, interbreeding between island groups does occur (Nagy 2011, p. 33).

Island groups are organized based on factors such as physical location and proximity of islands, management, observations of local communities, scientific observations, tracking of caribou herd migrations, and to some degree, genetic analyses. In 2015, COSEWIC divided the subspecies into four island groups (COSEWIC 2015, p. 8). For the purposes of this status review, we used the latest COSEWIC review to provide a map representing four island-complex regions (COSEWIC 2015, p. 8; Jenkins et al. 2011, p. 13; COSEWIC 2004, p. 12). See map, below.

BILLING CODE 4333-15-P

EP31AU21.000

BILLING CODE 4333-15-C
As noted above, the island populations are not reproductively isolated from each other; caribou travel hundreds of kilometers and can move among the Arctic Islands due to the sea ice that persists for almost 10 months of the year (COSEWIC 2015, p. 12; COSEWIC 2011, p. 23; McFarlane et al. 2003, pp. 128-129). Thus, while we discuss these four island groups of Peary caribou, uncertainty regarding the genetic distribution and movement of these subpopulations remains (COSEWIC 2015, pp. 25-26; SARC 2012, pp. 20, 29).

As of 2018, the estimated populations are presented in table 1, below.

Table 1—Estimates of Peary Caribou Populations in 2018 Based on Aerial Surveys

[Adapted from Jenkins et al. 2011, pp. 117-151,
1
Davison and Williams 2013, pp. 1-2,
2
COSEWIC 2015, pp. 33-34,
3
Anderson 2016, pp. iii, 14-19
4
.]

Island complex
Islands

Estimated
population

Year
surveyed

Territory

Banks Island—NW Victoria

Banks Island
3

NW Victoria
3

2,248
4

2014
2015

Northwest Territories.
Northwest Territories.

Melville Island
3

2,740
2012
Northwest Territories/Nunavut.

Prince Patrick
3

2,746
2012
Northwest Territories.

Western Queen Elizabeth Islands

Eglington Island
2

Byam Martin
3

181
121

2012
2012

Northwest Territories.
Nunavut.

Emerald Islands
2

45
2012
Northwest Territories.

McKenzie-King
3

36
1997
Northwest Territories/Nunavut.

Bordon Island
3

16
1973
Northwest Territories/Nunavut.

Brock Island
3

0
1997
Northwest Territories.

Bathurst Island
3

1,463
2013
Nunavut.

Cornwallis Island
1

~1
2013
Nunavut.

Ringnes Island
1

282
2007
Nunavut.

Lougheed Island
3

103
2007
Nunavut.

Devon Islands
4

69
2008
Nunavut.

Eastern Queen Elizabeth Islands

Axel Heiberg Islands
3

Ellesmere Islands
3

2,255
918

2007
2015

Nunavut.
Nunavut.

Prince of Wales-Somerset-Boothia Peninsula Island Complex

Prince of Wales
3

Somerset
3

Boothia Peninsula
3

1
4
1

2004
2005
2006

Nunavut.
Nunavut.
Nunavut.

Total estimated population in 2018: 13,234

Population Trends

The trend in population estimates since the 1960s demonstrates that Peary caribou populations have generally decreased with a partial recovery in the populations from 2010 through 2015 (COSEWIC 2015, pp. 32-43; Gunn et al. 2010, pp. 40-44). In 1961, the first comprehensive survey of Peary caribou across the Queen Elizabeth Islands was completed (Tener 1963, as cited in Jenkins et al. 2011, p. 2). Surveys in 1961 estimated the population to be approximately 26,000 Peary caribou on Queen Elizabeth Islands and approximately 22,000 Peary caribou on the larger southern islands and the Boothia Peninsula (Gunn et al. 2011 p. 40). However, the survey was not comprehensive, nor was it quantitative (Miller
et al
2005, pp. 65-66). The 1961 survey data were later reanalyzed, and the results were published in 2005. The new analysis determined the population estimate in 1961 for Peary caribou to be 28,288 with a range of 20,436-37,031 at a 95 percent confidence interval (Miller et al. 2005, p. 65).

While different methods and taxonomic changes affected the reliability of older surveys, recent surveys using consistent survey methods have provided additional clarity on the status of the subspecies. Between 1961 and 1973, an 83 percent reduction in the Peary caribou population is estimated to have occurred. Recent numbers are ~80 percent lower than the historical high population numbers seen 40-50 years ago (SARC 2012, p. xvi; Gunn et al. 2011, pp. 37, 40). The declines were attributed to deep snow layers and icing, which likely caused widespread mortality and resulted in little or no reproductive success (Miller et al. 1975; entire). However, stochastic, periodic die-off followed by a population rebound is a characteristic of the Peary caribou ecology (COSEWIC 2015, p. 32). Overall, the trend data suggest some populations have experienced significant declines while others have recovered. On Banks Island, the subpopulation declined from 1982 to 1992 but stabilized at low levels from 1992 through 2010. The population on Banks Island was estimated to be 2,351 in 1959, and declined to as low as 451 in 1998, before recovering to 1,142 in 2001, and 2,234 in 2014 (COSEWIC 2015, p. 35). While the subpopulation on Banks Island appears to have stabilized, the subpopulation on Victoria Island has suffered almost a 100 percent decline. The Peary caribou subpopulation on Victoria Island declined from 4,512 caribou in 1980 to 159 in 1993. Potential reasons for the decline include hunting and disease. A survey in 2015 recorded only two individuals (COSEWIC 2015, p. 36).

Similar to the conditions on Victoria Island, the Prince of Wales-Somerset-Boothia Island complex appears to have also suffered a total decline. The subpopulation of this island group reached a maximum number of 10,000 individuals between 1980 and 1985 before plummeting to a handful of individuals in the early 2000s (COSEWIC 2015, p. 36). The cause for this decline remains unknown, although a number of possible reasons such as extreme weather, wolf predation, hunting, disease, and competition with muskoxen were suggested (COSEWIC 2015, p. 37).

In contrast to the subpopulation on Victoria Island and the Prince of Wales-Somerset-Boothia Island complex, the Peary caribou subpopulation on Western Queen Elizabeth Island has stabilized and is increasing. While the subpopulation experienced two catastrophic die-offs (declines ranging from 72 percent to 92 percent) from weather extremes in 1974-1975 and 1996-1997, it appears to have recovered. In 2012-2013, the population was an estimated 7,300 adults, an increase from the 1986-1988 survey population of 2,500 individuals (which includes calves) (COSEWIC 2015, p. 38; Jenkins et al. 2011, p. 120).

Due to its location in the far northern part of the Peary caribou's range, partial surveys of the Eastern Queen Elizabeth Island group have been conducted over the years. A complete survey of the island group was not completed until 2007; that survey yielded 2,291 caribou (COSEWIC 2015, pp. 41-42). Recent surveys suggest the population is increasing. However, this higher number could simply be the result of the larger area covered by the more recently conducted surveys (COSEWIC 2015, p. 42)

As of 2015, the number of Peary caribou was estimated to be approximately 13,700 in Canada (COSEWIC 2015, p. 42). While some island groups have experienced a significant decline, others are more stable or increasing. One subpopulation (Prince of Wales-Somerset-Boothia island complex) had fewer than 10 individuals at the last count in 2005, with no evidence of any recovery. However, despite experiencing declines in the 2000s, the Banks Island population has returned to its 1959 numbers. The WQEI subpopulation, which now accounts for almost half of the extant population, has recovered from a catastrophic die-off in the 1990s and experienced increases for the 15-year period between 1997 and 2012. Overall, while the Peary caribou experienced population declines in the 1990s due to icing events and other factors, the subspecies has since experienced an increase of about 150 percent within the past two decades (COSEWIC 2015, pp. 42-43).

Conservation Status of the Peary Caribou

The Peary caribou subspecies was listed as endangered under Canada's Federal Species at Risk Act (SARA) in February 2011, due to a decline in its population size, and due to expected changes in long-term weather patterns (Giroux et al. 2012, p. 4; COSEWIC 2004, pp. 36-41, 51-58). Under SARA, an “endangered species” is defined as a species facing imminent extirpation or extinction (Statue of Canada (SC) 2002, c. 29). SARA makes it an offense to kill, harm, harass, capture, or take an individual of a listed species that is endangered, threatened, or extirpated; possess, collect, buy, sell, or trade an individual of a listed species that is extirpated, endangered, or threatened—or its part or derivative; or damage or destroy the residence of one or more individuals of a listed endangered or threatened species (or of a listed extirpated species, if a recovery strategy has recommended a reintroduction site). Subsistence hunting by indigenous communities is generally exempt from prohibitions under SARA (COSEWIC 2015, p. 52). Caribou are granted protections by various mechanisms in Canada such as land-claim agreements, and hunts are co-managed by boards such as the Nunavut Wildlife Management Board, the Wildlife Management Advisory Council in the Northwest Territory, and hunting and trapping associations (COSEWIC 2004, p. 61). Both a Federal recovery strategy and territorial management plan are currently being developed for this subspecies (Giroux et al. 2012, p. 4). Due to improvement in the subspecies condition, COSEWIC reassessed this subspecies as threatened in 2015 (COSEWIC 2015, p. 56). This reassessment does not change the subspecies' status under SARA, which requires an amendment to the SARA listing. The subspecies' status is currently being reviewed under SARA based on the COSEWIC 2015 reassessment (Carriere 2017, pers. comm.).

Caribou are recognized at the species level as “vulnerable” by the International Union for Conservation of Nature (IUCN) (the Peary caribou subspecies is not addressed by the IUCN) (Gunn 2016, unpaginated). The IUCN identifies and documents those species considered to be most in need of conservation attention if global extinction rates are to be reduced and is recognized as an approach for evaluating the conservation status of plant and animal species; however, designations by the IUCN convey no actual protections.

Regulatory Framework

Section 4 of the Act (16 U.S.C. 1533) and its implementing regulations (50 CFR part 424) set forth the procedures for determining whether a species is an “endangered species” or a “threatened species.” The Act defines an endangered species as a species that is “in danger of extinction throughout all or a significant portion of its range,” and a threatened species as a species that is “likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range.” The Act requires that we determine whether any species is an “endangered species” or a “threatened species” because of any of the following factors:

(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.

These factors represent broad categories of natural or human-caused actions or conditions that could affect a species' continued existence. In evaluating these actions and conditions, we look for those that may have a negative effect on individuals of the species, as well as other actions or conditions that may ameliorate any negative effects or may have positive effects.

We use the term “threat” to refer in general to actions or conditions that are known to or are reasonably likely to negatively affect individuals of a species. The term “threat” includes actions or conditions that have a direct impact on individuals (direct impacts), as well as those that indirectly affect individuals such as through alteration of their habitat or required resources (stressors). The term “threat” may encompass—either together or separately—the source of the action or condition, or the action or condition itself.

However, the mere identification of any threat(s) does not necessarily mean that the species meets the statutory definition of an “endangered species” or a “threatened species.” In determining whether a species meets either definition, we must evaluate all identified threats by considering the expected response by the species, and the effects of the threats—in light of those actions and conditions that will ameliorate the threats—on an individual, population, and species level. We evaluate each threat and its expected effects on the species, then analyze the cumulative effect of all of the threats on the species as a whole. We also consider the cumulative effect of the threats in light of those actions and conditions that will have positive effects on the species—such as any existing regulatory mechanisms or conservation efforts. The Secretary determines whether the species meets the definition of an “endangered species” or a “threatened species” only after conducting this cumulative analysis and describing the expected effect on the species now and in the foreseeable future.

The Act does not define the term “foreseeable future,” which appears in the statutory definition of “threatened species.” Our implementing regulations at 50 CFR 424.11(d) set forth a framework for evaluating the foreseeable future on a case-by-case basis. The term foreseeable future extends only so far into the future as the Services can reasonably determine that both the future threats and the species' responses to those threats are likely. In other words, the foreseeable future is the period of time in which we can make reliable predictions. “Reliable” does not mean “certain”; it means sufficient to provide a reasonable degree of confidence in the prediction. Thus, a prediction is reliable if it is reasonable to depend on it when making decisions.

It is not always possible or necessary to define foreseeable future as a

particular number of years. Analysis of the foreseeable future uses the best scientific and commercial data available and should consider the timeframes applicable to the relevant threats and to the species' likely responses to those threats in view of its life-history characteristics. Data that are typically relevant to assessing the species' biological response include species-specific factors such as lifespan, reproductive rates or productivity, certain behaviors, and other demographic factors.

Analytical Framework

The species reports document the results of our comprehensive biological status review for the two subspecies, including an assessment of the potential threats to the subspecies. The reports do not represent decisions by the Service on whether the species should be proposed for listing as endangered or threatened species under the Act. They do, however, provide the scientific basis that informs our regulatory decisions, which involve the further application of standards within the Act and its implementing regulations and policies. The following is a summary of the key results and conclusions from the reports; the full reports can be found at [Docket FWS-HQ-ES-2019-0014 on
http://www.regulations.gov
].

Summary of Biological Status and Threats

In this section, we review the biological condition of the Peary caribou and its resources and factors that affect the species to assess the species' overall persistence. The Peary caribou lives in a harsh environment that is sparsely populated with people, and this subspecies is not consistently monitored in all locations where it exists. Caribou biologists have suggested a number of potential threats that are likely contributing to the decline of the Peary caribou. The primary threats will be discussed below. We also assessed other threats that we concluded to have minor effects on the species; those assessments can be found in our Species Report. The minor threats are disease, predation (primary by wolves), and competition with other species for food (including other caribou and muskox). The major threats that will be discussed below are:

• Effects of climate change;

• Inaccessibility of food due to snow and ice conditions;

• Hindered ability to seasonally migrate due to lack of sea ice;

• Disturbance due to development, oil and gas exploration, or shipping;

• Parasitic harassment by botflies; and

• Hunting

Climate Change

Changes in climate and weather patterns are suspected to be a major contributor to the decline of this subspecies (COSEWIC 2015, p. 44; Hansen et al. 2011, p. 1,922; Miller and Barry 2009, p. 175; Prowse et al. 2009a, p. 269; Tews et al. 2007, pp. 95-96; COSEWIC 2004, pp. viii, 55-58). Our analysis under the Act includes consideration of ongoing and projected changes in climate. The terms “climate” and “climate change” are defined by the Intergovernmental Panel on Climate Change (IPCC). The term “climate change” thus refers to a change in the mean or variability of one or more measures of climate (
e.g.,
temperature or precipitation) that persists for an extended period, typically decades or longer, whether the change is due to natural variability, human activity, or both (IPCC 2013, p. 1,450).

As noted above, to determine whether these species are threatened, we must evaluate threats and the species' response to threats over “the foreseeable future.” The demographic, ecological, and evolutionary responses of caribou to threats resulting from climate change are complicated to predict. The complexity stems from the species' habitat requirements and resilience to the effects of climate change. Current models for the Arctic predict deeper snow cover, increasing rainfall, more thawing-freezing cycles, and a higher risk of ice-layer formation on the soil within the snowpack during the winters of the coming decades (Steiner et al. 2013, p. xii; Hansen et al. 2011, p. 1,917; Turunen et al. 2009, pp. 813-814; Putkonen and Roe 2003, entire). Under these models, caribou populations will respond negatively to climate change due to the occurrence of more precipitation, greater snowfall, and subsequently more freezing-rain events, which will make access to food more difficult (COSEWIC 2015, pp. 44-46; Hummel and Ray 2008, pp. 137-141; Miller et al. 2007, p. 33). Reduced access to food would lead to increased starvation, die-offs, and reduced calf production and recruitment, which are highly dependent on the female's physical condition, specifically on fat reserves (Governments of the Northwest Territories and Nunavut 2018, p. 28). However, other models support a conclusion that Peary caribou may experience increases in population numbers if climate change results in a 50 percent increase of taller, denser vegetation and woody shrubs (Tews et al. 2007, pp. 95 96). As ecological systems are dynamic, it is complicated to predict how one change (such as a rise in temperature) will affect other elements within the ecosystem (such as the amount of precipitation that falls as freezing rain, rather than snow) (Green and Sadedin 2005, pp. 117-118; Burkett et al. 2005, entire). Given that caribou experts consider the primary threat to the Peary caribou to be climate-change related, we rely on climate projection models undertaken by the IPCC (IPCC 2014a, pp. 8-12). The models discuss future trends for precipitation and air and water temperature, which have an impact on the caribou's habitat.

Projections of sea-ice loss using RCP 4.5 and 8.5 scenarios and rain-on-snow events in the Canadian Arctic vary in their time scale (Mallory and Boyce 2018, p. 2,192; Jenkins et al. 2016, p. 4; Engler and Pelot 2013, p. 21; Stroeve et al. 2012, p. 1,012). While all climate models agree that sea-ice loss will occur in the Canadian Arctic, there is disagreement on when sea-ice loss will result in an ice-free period. Some models project the Canadian Arctic will experience ice-free periods as early as 2050 while others project that due to the influx of sea ice from the Arctic Ocean, sea ice in the Canadian Arctic will persist into the 2080s (Li et al. 2019, pp. 1 2; Derksen et al. 2018, p. 198; Mallory and Boyce 2018, pp. 2,194 2,195; Johnson et al. 2016, p. 16; Jenkins et al. 2016, p. 4). This uncertainty is due in part to the flow of sea ice from the Arctic to the east coast of the Canadian Arctic Archipelago (Derksen et al. 2018, p. 218).

In addition to sea-ice loss, the thinning of sea ice can also have an impact on the caribou. This is because if sea ice is too thin, it will not be able to support the caribou's weight. We thus take into consideration changes in ratio over time between the thinner first-year ice versus the thicker, multiyear ice (Li et al. 2019, p. 2). Additionally, as seen in the population trend above, Peary caribou subpopulations can fluctuate widely from year to year and mass die-off events can occur within a single season. We thus need to identify a timeframe long enough to observe changes in the subspecies.

Most models project that portions of the Canadian Arctic will be ice free by 2040-2060 (Derksen et al. 2018, pp. 198, 218; Johnson et al. 2016, p. 16; Lu et al. 2014, p. 61). Although we possess projections that go out to 2100, there is greater uncertainty between the climate model projections in the latter half of the 21st century and how the effects of climate change will affect species response when projected past mid-century. Accordingly, we determined that the foreseeable future extends only

to 2050 for the purpose of this analysis and we rely upon projections out to 2050 for predicting changes in the species conditions. This timeframe allows us to be more confident of assessing the impact of climate change on the species. Therefore, based on the available climate projection and information we have on the subspecies, we have determined 2050 as the foreseeable future timeframe for the Peary caribou.

One additional concept that adds to the uncertainty of what will occur in the Arctic ecosystem is “sudden climate change,” an amplified response that has been a concern to scientists for several years (Hansen et al. 2011, p. 1,917; Barber et al. 2008, p. 8). Surface temperature and albedo (reflection of sunlight) are two critical factors of the Arctic climate system (Wang et al. 2012, p. 2). An area that does not contain snow absorbs more heat than an area covered with snow (areas with snow reflect more heat), so the albedo effect is less in areas of the Arctic that lack snow and ice (Stroeve et al. 2012, p. 1,012). The Arctic climate both affects global-scale climate change and is affected by it through feedback mechanisms (Barber et al. 2008, p. 8). All combinations of models and emission scenarios yield increases in global temperature. Therefore, if there are large-scale changes in temperature, the weather patterns could change drastically, and the overall effect on the ecosystem is unknown.

We acknowledge that the climate is changing in the Arctic region, and based on the best scientific and commercial information available on Peary caribou, we reach reasonable conclusions about the likely impacts specific changes in climatic conditions may have on the species over the foreseeable future, which will be discussed below (IPCC 2014b, entire; Schiermeier 2011, p. 185; Olsen et al. 2011, entire; Liston and Hiemstra 2011, p. 5,691; Prowse et al. 2009b, entire; Turunen et al. 2009, p. 813; Barber et al. 2008, entire; Rinke and Kethloff 2008, p. 173).

Snowpack, Ice Events, and Food Availability

One of the major causes of catastrophic die-offs of caribou is the formation of hard, crusted snow or layers of ice on the ground, which restricts the animals' access to forage (COSEWIC 2015, p. 44; COSEWIC 2004, pp. 51-53; Miller and Gunn 2003, pp. 385-386). These layers of ice crust form in several ways. One way is repeated cycles of thawing and refreezing of the snowpack (Tyler et al. 2008, p. 1,679). Ice layers can also form due to freezing rains or rain-on-snow events (Miller and Barry 2009, p. 182; Putkonen and Roe 2003, pp. 37-1-37-2). A third way is when spring melt water trickles through the snow-pack and freezes as it comes into contact with the very cold ground beneath (Woo and Heron 1981, as cited in Tyler 2010, p. 198).

Layers of thick ice block access to food and influence caribou movement patterns by pushing herds to move to areas with less ice but poorer forage (Hansen et al. 2011, p. 1,921; Stien et al. 2010, p. 917). The decline of Peary caribou in four major die-offs in western Queen Elizabeth Islands between 1970 and 1998 coincided with extremely heavy snowfall, deep snow-packs, and heavy icing, which limited access to forage, increased energy expenditure, and led to extreme malnourishment and subsequent mass starvation events (Jenkins et al. 2011, p. 6; Miller and Barry 2009, p. 176; Gunn et al. 2006, p. 6; Adams and Dale 1998a, as cited in Tyler 2010, p. 198).

Climate change is expected to cause heavier and more frequent snowfall events, more variable weather patterns, freezing rain, and higher layers of snow during these winter events (Steiner et al. 2013, p. 83; Turunen et al. 2009, p. 813, COSEWIC 2004, pp. 51-53). Due to changes in temperature, air-circulation patterns, and ocean-circulation changes, precipitation is expected to increase strongly during the summer season. Some caribou researchers project that, as temperatures rise, more severe weather patterns will occur and will cause increased snow and ice cover over vegetation. Under this scenario, food availability is projected to decrease. If these conditions occur, Peary caribou could suffer additional widespread starvation events, thereby decreasing the resiliency of the subspecies (Miller and Gunn 2003, p. 386).

Loss of Sea Ice

Sea ice is a vital component of the seasonal migrations of the Peary caribou. Peary caribou use multiple islands throughout their annual migrations and require sea ice to cross between islands. Older, multiyear sea ice is becoming less prevalent. In Canada's Arctic Archipelago, sea ice can attain a thickness of 4 to 6 meters (13 to 20 ft) (Haas et al. 2006, as cited in Meier et al. 2011, p. 9-13). Within the range of the Peary caribou, these old layers of sea ice are vital for crossing between islands. The majority of the ice in the Arctic Ocean is now young, “first-year” sea ice, which is not only more susceptible to summer melt, but is also thinner and less able to support caribou during their seasonal migrations (COSEWIC 2015, p. 44; SARC 2012, p. 25; Meier et al. 2011, pp. 9-6-9-8; Prowse et al. 2009a, p. 266). Sea ice in the Arctic has been at extremely low summer levels in recent years. Most of the oldest typical forms of sea ice (which were usually more than 5 years old) no longer exist (Meier et al. 2011, p. 9-4).

Since the beginning of monitoring in 1979, record low levels of sea ice have occurred in recent years. From 1968 to 2015, sea ice declined at a rate of 6.1 percent per decade (Environment and Climate Change Canada 2016, p. 8). Multiyear ice, which is thick enough to support the caribou's weight, has been declining over time. In the mid-1980s, multiyear ice accounted for 75 percent of all ice in the Arctic. By 2011, it accounted for 45 percent of all ice (Li et al. 2019, p. 2). Additionally, landfast ice has also been decreasing. This is important to the Peary caribou as the Canadian Arctic Archipelago contains many narrow channels that the subspecies uses for its migration corridors. Over the 10-year intervals starting in 1976, the maximum extent of landfast ice was: 2.1 × 10
6
km
2
(1976-1985), 1.9 × 10
6
km
2
(1986-1995), 1.74 × 10
6
km
2
(1996-2005), and 1.66 × 10
6
km
2
(2006-2018) (Li et al. 2019, p. 5).

EP31AU21.001

Sea-ice loss is likely to continue and accelerate throughout this century, and Arctic seas may be seasonally ice-free as early as 2040 (Engler and Pelot 2013, p. 21; Meier et al. 2011, p. 9-3; Olsen et al. 2011, p. 112; Wang and Overland 2009, p. 1; Boé et al. 2009, p. 1). Decreased ice concentrations during warmer summer temperatures result in significant heating of the ocean surface, which then further increases ice melt (Stroeve et al. 2012, p. 1,012; Meier et al. 2011, p. 9-16). As a consequence of earlier ice-break-up dates and later freeze-up dates, caribou would have to begin their spring migration earlier to ensure safe passage over large water bodies or possibly shift their distribution in search of food sources (COSEWIC 2015, p. 46; Post and Forchhammer 2008, as cited in Sharma et al. 2009, p. 2,559). Some researchers have theorized mass drownings have occurred during migrations when sea ice was too thin to support the weight of the caribou (SARC 2012, pp. 35, 47). Additionally, changes in sea ice may inhibit movement of populations, which could lead to certain subpopulations being geographically isolated and the potential for reduced genetic diversity within the subspecies (SARC 2012, p. xvii).

While the overall climate trend for the Canadian Arctic points toward a decreasing ice level over time, the condition in the Canadian Arctic Archipelago is likely to experience slower ice loss. Overall, the Canadian Arctic archipelago possesses the thickest Arctic sea ice (Li et al. 2019, p. 1). The growth of multiyear ice within the Peary caribou's range is the result of both first-year to multiyear ice conversion and the arrival of multiyear ice from the Arctic Ocean located to the west (Pizzolato 2015, p. 4). This Arctic Ocean sea ice wedges up against the western portions of the WQEI making the sea ice in the region the oldest and thickest in the world, with some ice potentially reaching 6-8 meters thick. The result is that the western Canadian Arctic multiyear ice makes up as much as 50 percent of all sea ice (Li et al. 2019, p. 7 Engler and Pelot 2013, p. 25).

In summary, while the increasing temperatures related to climate change have produced a marked decrease in sea ice throughout the Arctic that is projected to continue into the foreseeable future, sea-ice loss in Peary caribou habitat is not as pronounced due to the unique geography of the region. In situ formation of multiyear ice as well as new ice from the Canadian Basin creates a condition that allows multiyear ice to persist for a longer period. The persistence of multiyear ice in the region facilitates the continued existence of migration corridors for the Peary caribou. This is expected to allow the species to continue to have access to food resources, thereby maintaining the resiliency of the subspecies to future stochastic events.

Summary of Climate Change

As a subspecies native to Canada's far north, the Peary caribou is affected by climate change in multiple ways. Climate change increases the frequency of ice events, which limits access to forage, and has been linked to major die-offs (Hansen et al. 2011, p. 1,921; Jenkins et al. 2011, p. 6; Stien et al. 2010, p. 917). On the other hand, the effects of climate change on plant phenology and composition remain more uncertain. Potential effects of climate change include a delay in the emergence of green foliage during the spring and decreasing shrub cover with

an increase in the number of shrub species (Chen et al. 2009a, pp. 17-19; Miller and Gunn 2003, p. 386). However, an increase in shrub species does not translate to higher nutritional content for caribou (COSEWIC 2015, pp. 22, 25). Whether Peary caribou will be able to adapt to these changes remains unknown. While uncertainty remains about the effects of climate change on plant condition, the continued persistence of multiyear sea ice in the species' range facilitates the continued existence of migration corridors for the Peary caribou (Pizzolato 2015, p. 4; Engler and Pelot 2013, pp. iii, 25; Meier et al. 2011, p. 9-3; Boé et al. 2009, p. 1; Wang and Overland 2009, pp. 1-4). The Peary caribou is found in Canada's high Arctic, which comprises a number of islands. The Peary caribou subpopulation's continued ability to migrate between these islands in search of food will help maintain the resiliency of the species to future stochastic events.

Exploration, Shipping, and Other Developmental Activities

Peary caribou herds appear to be affected by human activities during the caribou's inter-island migrations and during calving season.

The projected decline of sea ice may lead to an increase of shipping traffic through the Northwest Passage. Between 1990 and 2011, shipping traffic increased by 75 percent (COSEWIC 2015, p. 49). Ships sailing through the Passage break up the ice impeding migration between islands. The Peary caribou then have to spend additional time waiting for the ice to reach sufficient thickness for crossing. Caribou have been observed at the water's edge waiting for the ice to re-freeze, even up to several days (Poole et al. 2010, p. 426). These events can cause significant decreases in body fitness if there is not adequate nutrition available for the herd while they are waiting to cross a body of water. Increased shipping is likely to affect island complexes farther to the south of the subspecies' range, including Prince of Wales and Somerset Island and the Bathurst-Cornwallis island group (COSEWIC 2015, p. 50). Islands farther to the north, such as Ellesmere, Axel Heiberg, or the Ringnes group, are likely to be less impacted due to the presence of pack ice and being far away from major trade lanes (COSEWIC 2015, p. 50; Engeler and Pelot 2013, p. 9). A high concentration of sea ice within the Queen Elizabeth Islands and difficult terrain will restrict ship traffic in this region (Pizzalato 2015, p. 4).

Movements of caribou indicate that they avoid seismic lines, roads, and other infrastructure (Nagy 2011, pp. 158-159; Latham 2011, p. 2,854). Seismic lines are vital components of oil and gas exploration and development (Nagy 2011, pp. 10-11). Although an earlier study suggested that caribou were not significantly disturbed by human presence (Slaney et al. 1975, as cited in COSEWIC 2004, p. 46), an abundance of information since then supports a conclusion that these activities do affect caribou behavior (Nagy 2011, pp. 158-159; Jenkins et al. 2011, p. 6; Hummel and Ray 2008, pp. 210, 219; Mahoney and Schaefer 2002, pp. 147, 151). In addition to scientific studies, anecdotal reports in Resolute Bay (Cornwallis Island, Nunavut) and Grise Fiord (Ellesmere Island, NWT) indicate that exploration activities for resources such as oil and gas are an additional threat for caribou (Jenkins et al. 2011, p. 6). Local Inuit communities also expressed concern that industrial activities can increase avoidance behavior and pollution and spills can adversely affect the health of the caribou (COSEWIC 2015, p. 54). Caribou biologists appear to generally be in agreement that these exploration and development activities have been observed to deter caribou from moving into areas that are vital for their survival (Nagy 2011, p. 158; Jenkins et al. 2011, p. 6).

While development has the potential to impact the Peary caribou by increasing energy expenditure, exploration and developmental activities have declined in recent years. Oil and gas exploration in the Peary caribou range peaked in the 1960s and 1970s (COSEWIC 2015, p. 54). Although exploration efforts have continued since then, it has not resulted in a large increase in mining or extraction sites (COSEWIC 2015, pp. 54-55). This is due to fluctuating market prices having a significant impact on extent and intensity of activities. In addition, environmental reviews undertaken by provincial governments have also slowed the rate of exploration and developmental activities (COSEWIC 2015, pp. 53-54). That said, there are currently active mining and extraction sites within the Peary caribou range. However, these sites remain localized and only impact nearby herds (COSEWIC 2015, p. 55). Overall, while current exploration and extraction efforts do result in negative effects to the Peary caribou, the effects on the overall subspecies are likely to be more limited.

In summary, the best available information supports that current levels of exploration, development, and shipping activities may have some negative effects on the Peary caribou resulting in behavioral changes in response to these activities. However, at present, these activities do not rise to the point where there is a significant impact to the subspecies (COSEWIC 2015, p. 55; Taylor 2005, as cited in Jenkins et al. 2011, pp. 6, 8, 118).

Parasitic Harassment by Botflies

Botflies, oestrids from the family Oestridae, have been identified as a potential threat that can affect Peary caribou in the future with a warming climate. Caribou species serve as host to two oestrid species: Warble flies (
Hypoderma tarandi
) and nose bot flies (
Cephenemyia trompe
). In the Arctic region, few hosts are available for parasites; warble flies and nose bot flies are particularly well adapted to survive in the Arctic climate using caribou as their host. Although these oestrids are widespread throughout the summer range of most caribou herds, they are considerably less prevalent in the high Arctic as they are at the latitudinal extreme of their range due to temperature, hours of daylight, and wind conditions (Gunn et al. 2011, pp. 13-14; Kutz et al. 2004, p. 114). However, some researchers have expressed concern that, should warming trends continue, the parasitic rate of development and infectivity timeframes could become altered, which may increase the energy expenditure of Peary caribou through avoidance behavior. Prolonged avoidance behavior increases the risk of the caribou succumbing to other illnesses, exposure to predation, and decreased survival rates of offspring (Kutz et al. 2004, p. 114; Kutz et al. 2001, as cited in Kutz et al. 2004, p. 112).

Warble Flies

Behavioral changes in response to insect harassment have commonly been observed in caribou. Warble flies trigger panic responses in caribou when they swarm around them. Warble flies live on the flesh underneath the skin of caribou. As many as 458 warble larvae have been documented on a single caribou (Hughes et al. 2008, p. 257). Adult females lay their eggs on caribou's body hair. After hatching, the larvae penetrate the skin and live subcutaneously over the winter until the next spring. The larvae spend the winter growing under the skin on the caribou's back, feeding on the flesh of the caribou. The larvae create a hole through the caribou's flesh and skin so the larvae can breathe. Between May and June, the larvae leave their host through the breathing pore in the skin, pupate on

the ground, and after a few weeks metamorphose inside a pupal case into adult flies (Nilssen 1997, p. 296). The peak emergence of these oestrids is in July.

Parasites deprive their hosts of energy that could be normally used for growth, maintenance, or reproduction (Cuyler et al. 2012, p. 251; Ballesteros et al. 2011, p. 34; Hughes et al. 2008, entire; Colman et al. 2003, p. 11; Hagemoen and Reimers 2002, pp. 883-884). The warble flies create an opening in the skin, and these open wounds make caribou more susceptible to blood loss and bacterial infections, which increase their energy expenditure (Scheer 2004, pp. 10-11). Severe insect harassment negatively affects growth rates and body size of caribou (Helle and Tarvainen 1984, as cited in Weladji et al. 2003, p. 80). When food availability is limited during the winter season, caribou lose body fat and catabolize protein (muscle) reserves (Miller 2003, as cited in Hughes et al. 2008, p. 253). Body mass is a fitness-related trait in caribou. Females need at least six percent body fat to reproduce (Jenkins 2012, personal communication). Heavier females are more likely to reproduce than lighter females, and increased weights prior to winter assist in preventing winter starvation (Ballesteros et al. 2011, p. 34).

Temperature and cloud cover are vital factors for harassment of caribou by warble flies as these two factors affect the flies' activity level (Weladji et al. 2003, p. 80; Nilssen 1997, p. 301). Warble flies are most active during warm, sunny days; warble fly activity increases as the temperature increases (Weladji et al. 2003, pp. 80-81). Within the Arctic, the annual mean surface temperature has increased at a rate of 0.34 °C (0.61 °F) per decade (Wang et al. 2012, p. 1). Throughout the Queen Elizabeth Islands, the mean average daily temperature from December to February is between −35 °C and −27 °C (−31.0 °F and −16.6 °F). In July, the mean average daily temperature is between −1 and 3 °C (33.8 and 37.4 °F) (Meteoblue 2017, unpaginated). General circulation models and other climate models indicate that average annual temperatures will increase 3-6 °C by 2080 (Meier et al. 2011, pp. 9-17-9-18; Olsen et al. 2011, p. 112). Based on these anticipated temperatures, we calculated the expected temperatures if the temperature was to increase by 3 °C (scenario 1) and by 6 °C (scenario 2). The climate models used in this table used a previous set of scenarios known as the Special Report on Emissions Scenarios (SRES) to project the low-emissions using scenario (SRES B1) and high-emissions scenario (SRES A2) (Marengo et al. 2011, p. 27). More recently, a newer set of scenarios (
i.e.,
RCPs) were prepared that include a wider range of future conditions and emissions. However, to compare the SRES and RCP scenarios, SRES B1 is roughly comparable to RCP 4.5 and SRES A2 is similar to RCP 8.5 (Melillo et al. 2014, p. 821). These similarities between specific RCP and SRES scenarios make it possible to compare the results from different modeling efforts over time (Melillo et al. 2014, p. 821). See table 2, below.

Table 2—Queen Elizabeth Islands: Temperature Increase Scenario up to 2080
[Adapted from Meier et al. 2011, p. 9-18; Olsen et al. 2011, p. 112.]

Month
Mean average daily temp.
Current conditions
Scenario 1 (temperature increase by 3 °C)
Scenario 2 (temperature increase by 6 °C)

December
Low
−35 °C
−31 °F
−32 °C
−26 °F
−29 °C
−20 °F

High
−27 °C
−16.6 °F
−24 °C
−11 °F
−21 °C
−5.8 °F

July
Low
−1 °C
30.2 °F
2 °C
35.6 °F
5 °C
41 °F

High
3 °C
37.4 °F
6 °C
42.8 °F
10 °C
50 °F

The low temperature threshold for warble fly activity is around 10 °C (50 °F) (Vistness et al. 2008, p. 1,312; Weladji et al. 2003, p. 81; Nilssen 1997, pp. 296, 300; Breyev 1961, as cited in Nilssen and Anderson 1995, p. 1,236). Farther north, temperatures became low enough that the warble fly is not able to survive and reproduce. Because parasitic fly harassment is low below 13 °C (55.4 °F), and because no oestrids fly below 10 °C (50 °F), this temperature threshold is significant for caribou, particularly the Peary caribou with respect to warble fly harassment. While scenario 1 will not lead to a significant increase in fly activity, if the temperature increases to 10 °C, as is the case in scenario 2, there is potential for warble fly harassment to increase, resulting in decreasing fitness, which could lead to increasing mortality due to disease, predation, and stochastic weather events. However, given the fact that Peary caribou reside in the northernmost range of the warble flies, the impact from harassment may be more limited.

Nose Botflies

Caribou experts consider the potential negative effect of the nose bot fly on caribou to be less than that of the warble flies. While the type of effects are similar between the two species of flies, such as causing avoidance behavior in caribou, the magnitude of those effects are not as extreme for the nose botfly as that caused by the warble fly. This species enters the caribou through the caribou's nose and lives in the caribou's throat for part of its life cycle (Whitney 1999, p. 2). The caribou exhibit distress from this species—they have been observed to duck their heads under water to avoid nose botflies (Witter et al. 2012, p. 284; Fauchald et al. 2007, pp. 496-497). An increase in the temperature by more than 10 °C in July could increase harassment of nose bot flies on the Peary caribou resulting in elevated energy expenditure and reduced forage time, although the severity will not be as high as for warble flies.

Summary of Parasitic Harassment

We note that a threat to a species and the species' response to that threat are not in general equally predictable or foreseeable. The demographic, ecological, and evolutionary responses of Peary caribou to threats from a warming climate are very complicated to predict, even though future warming is highly likely to occur. Oestrid flies could expand their range, and they could possibly negatively affect the Peary caribou. The lower temperature threshold for warble fly activity has been determined to be around 10 °C (50 °F), which occurs in the most northern part of the Peary caribou's range. A warmer climate is very likely to affect the distribution and abundance of warble flies. However, the best available information indicates that, due to the very low temperatures in the Peary caribou's range, oestrid harassment will not significantly negatively affect the Peary caribou now or in the foreseeable future (Jenkins

2012, personal communication; Hummel and Ray 2008, p. 217).

Status of Existing Regulatory Mechanisms

Under the Act, we are required to evaluate whether the existing regulatory mechanisms are adequate. As previously explained, the Peary caribou subspecies was listed as endangered under Canada's SARA in February 2011, due to its apparent decline in population size and due to expected changes in long-term weather patterns (Giroux et al. 2012, p. 4). SARA makes it an offense to kill, harm, harass, capture, or take an individual of a listed species that is endangered, threatened, or extirpated; possess, collect, buy, sell, or trade an individual of a wildlife species that is listed as extirpated, endangered, or threatened, or any part or derivative of such an individual; damage or destroy the residence of one or more individuals of a listed endangered or threatened species or of a listed extirpated species if a recovery strategy has recommended its reintroduction (SC Ch. 32.1 § 32.2). However, exceptions to SARA prohibitions enable Indigenous peoples to exercise their harvesting rights (COSEWIC 2015, p. 52). Additionally, permits may be issued under certain conditions if the activity is conducted for scientific research, benefits the species or is required to enhance its chance of survival in the wild, or affecting the species is incidental to carrying out the activity (S.C. Ch 73).

In the NWT, the Species at Risk Committee (SARC) designated the Peary caribou as threatened within their Territory in 2012 (as 40-60 percent of the subspecies reside within the NWT) and Peary caribou were listed as threatened under the Species at Risk (NWT) Act in 2014 (SARC 2012, entire). Both the Federal recovery strategy and territorial recovery strategy management plan are currently being developed for this subspecies (Giroux et al. 2012, p. 4). For efficiency, the NWT Peary Caribou Recovery Strategy and the Federal Peary Caribou Recovery Strategy will be combined into a single document; although this plan was anticipated to be completed in February 2016, it has been extended to December 2021 due to the complex nature of caribou management (Species at Risk Act 2019, unpaginated SARC 2015, entire).

The Government of Canada may base a decision to list a species, assessed by COSEWIC at some level of endangerment, on social or economic factors (Festa-Bianchet et al. 2011, p. 422). Management must consider that subsistence hunting by indigenous people of all caribou is constitutionally guaranteed by treaty rights and land-claim agreements (Festa-Bianchet et al. 2011, pp. 423-424). In addition, subsistence hunting is not typically monitored by provincial wildlife management agencies, nor is reporting of barren-ground caribou harvest mandatory in Nunavut (Giroux et al. 2012, p. 12). They also note that a listing under SARA does not necessarily imply any additional conservation measures for lands directly under the control of the Federal Government (Festa-Bianchet et al. 2011, p. 423).

In Nunavut, the Department of Environment (DoE) is responsible for the management and conservation of caribou within its jurisdiction (Jenkins et al. 2011, p. 8). DoE shares management responsibility for Peary caribou with the Nunavut Wildlife Management Board and the Government of Canada. This responsibility is described in the Nunavut Land Claim Agreement 1993, Article 5 (Indian and Northern Affairs Canada 1993, as cited in Jenkins et al. 2011, p. 8).

In the NWT, the Government of NWT shares management responsibility for the Peary caribou with the Wildlife Management Advisory Council, the Inuvialuit Game Council, and the Government of Canada (AANDC 2012, p. 3). The relevant Canadian management authorities monitor aspects of caribou population health including body condition, diet, sex, and age, in part through harvest. Management and conservation actions are enforced through regulations under the Wildlife Act statutes of the Northwest Territories 2013 and through by-laws drafted at the community level by hunter and trapper committees and written into regulation. The Inuvialuit have taken a leadership role in the management of Peary caribou. For Banks Island, Peary caribou harvest quotas have been established for subsistence purposes (only hunting by Inuvialuit is allowed); quotas were implemented in 1991 and are reviewed annually. On NW Victoria Island, the Olokhaktomiut Hunters and Trappers Committee (Ulukhaktok) created specific zones that allow management actions such as enforcement of quotas (NWT 2016, p. 27; SARC 2012, pp. iii, xii; AANDC 2012, p. 3). In Resolute Bay, Nunavut, during the last decade, about 10-36 animals are hunted each year. Another 10-60 are hunted annually by residents on Ellesmere and Devon Island. In the Northwest Territory, annual harvest was reported to be 12 or fewer on Banks Island, and zero animals were taken from WQEI (COSEWIC 2015, p. 52). These numbers indicate that annual take of the Peary caribou by local hunters remains low. Additionally, local communities have voluntarily curtailed hunting when the Peary caribou population is in decline. For example, as a result of the mass die-off between 1995 and 1997, the Resolute Bay Hunters and Trappers Association prohibited hunting of Peary caribou on Bathurst Island. A similar ban was instituted by local communities at Sachs Harbor on Banks Island (COSEWIC 2015, p. 52).

Protection of habitat for Peary caribou has increased in the past few decades (Gunn et al. 2011, pp. 26-27). Since the early 1990s, three national parks have been established in areas that are important for Peary caribou (Government of Canada 2015, entire; Gunn et al. 2011, p. 27). In 1992, summer habitat for Peary caribou on northern Banks Island became a protected area as Aulavik National Park. In 2001, approximately one-fifth of Ellesmere Island became protected as Quttinirpaaq National Park (formerly Ellesmere Island National Park Reserve); this park is the second largest national park in Canada. The Qausuittuq National Park (formerly proposed as Tuktusiuqvialuk National Park) was created to provide protection for Peary caribou on northern Bathurst Island in 2015. However, despite designation as protected areas, the actual conservation measures that apply to these “protected areas” are unclear. These protected areas provide some protection for the Peary caribou through prohibiting land-use activities such as those for resource exploration and development. Hunting activities in the park is regulated through a permitting system. However, they do not prohibit other human activity such as tourism and aircraft flight (Gunn et al. 2011, pp. 26 27), nor do they address climate change. Some caribou researchers indicate that protection for migratory caribou calving grounds is still needed (Festa-Bianchet et al. 2011, p. 430).

In summary, the combined NWT/Federal Peary Caribou Recovery Strategy has not been completed; as a result, we are unable to evaluate whether this recovery plan will effectively mitigate the factors that are negatively impacting the Peary caribou. However, the development and enforcement of the harvest quota system in addition to other management efforts by the Wildlife Management Advisory Committee (Northwest Territories) on NW Victoria Island and Banks Island, both areas where the caribou populations seem to be stable, indicate that current regulatory mechanisms may be having a positive impact on the subspecies.

Synergistic and Cumulative Effects

Peary caribou live in a harsh environment, and their populations fluctuate in response to various factors. This subspecies is susceptible to abrupt changes in population size (Giroux et al. 2012, p. 4; Jenkins et al. 2011, pp. 9, 156). Population fluctuations are not the result necessarily of a single cause; they can occur due to a combination of environmental factors that are acting together.

Although the Peary caribou populations appear to have stabilized or slightly declined, the interactions within an ecosystem are complex, interrelated, and not linear and, therefore, complicated to predict (Tews et al. 2012, pp. 271, 275; Meier et al. 2011, p. 9-46). Subtle cumulative effects can occur when several factors act either singly at different times or in combination over the long term (Hovelsrud et al. 2011, p. 10-3; Miller et al. 2007, p. 33). The observed and the projected effects of a warming global climate are more extreme in northern high-latitude regions, in part due to the ice‐albedo feedback mechanism in which melting of snow and sea ice lowers reflectivity and thereby further increases surface warming by absorption of solar radiation (Wang and Overland 2009, p. 1; IPCC 2007a, p. 30). A warmer climate will interact with other factors that are affecting the Peary caribou, and the combination of all of these factors acting together affects the subspecies more than if just one factor was adversely affecting the subspecies.

The most significant threat affecting this subspecies appears to be extreme weather events that cause massive starvation events and death among herds. Additionally, the predicted trends related to the effects of climate change (snowpack and ice events), the potential for changes in the composition of plant communities, the expected continuation of loss of sea ice (changing migratory routes and access to critical habitats), and the subspecies' tendency towards small and isolated populations are cumulatively affecting this subspecies now and are expected to continue into the foreseeable future (SARC 2012, p. xvii; Joly et al. 2010, p. 322; Chen et al. 2009a, entire; Chen et al. 2009b, entire; Post and Forchhammer 2008, as cited in Sharma et al. 2009, p. 2,559).

Determination of Peary Caribou Status

Section 4 of the Act (16 U.S.C. 1533) and its implementing regulations (50 CFR part 424) set forth the procedures for determining whether a species meets the definition of “endangered species” or “threatened species.” The Act defines an “endangered species” as a species that is “in danger of extinction throughout all or a significant portion of its range,” and a “threatened species” as a species that is “likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range.” The Act requires that we determine whether a species meets the definition of “endangered species” or “threatened species” because of any of the following factors: (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. For a more detailed discussion on the factors considered when determining whether a species meets the definition of “endangered species” or “threatened species” and our analysis on how we determine the foreseeable future in making these decisions, please see the
Regulatory Framework
section above.

Status Throughout All of Its Range

We have carefully assessed the best scientific and commercial information available regarding the past, present, and future threats to the Peary caribou. As with all biota, there are many uncertainties about this subspecies, including how changes in climate will affect its ecosystem, in part due to the complexity of biological systems and processes, and we have made reasonable conclusions about the potential impacts these changes may have on the species based on the best scientific and commercial information available on Peary caribou. Extreme weather events (heavy snow and icing) affect plant phenology and the availability of nutrients within its ecosystem, which influence the caribou's annual life cycle, thus affecting the size of annual populations. The effects of weather events are particularly a threat with respect to some of the island populations that are extremely small. The threats likely to affect the Peary caribou are disruption of migration routes as a result of loss of sea ice (Factor A), reduced accessibility of vegetation resulting from extreme weather events and a changing climate (Factor A), changes in plant composition (Factor A), and synergistic and cumulative effects of all factors working in concert.

The vast majority of Peary caribou's habitat is covered by snow and ice for a significant portion of the year. Icing events are expected to increase (Steiner et al.
2013,
p. 83; Turunen et al. 2009, p. 813, COSEWIC 2004, pp. 51-54). This increase will reduce caribou access to food, and icing events in the past have historically been linked to major die-offs (Jenkins et al. 2011, p. 6). The loss of sea ice is very likely to occur due to warming temperatures throughout the Canadian Arctic (Shepherd et al. 2012, pp. 1,188-1,189; Sharp et al. 2011, pp. 1, 4). However, the northern range of the Peary caribou, the Queen Elizabeth Islands, contains some of the thickest sea ice in the world (Engler and Pelot 2013, p. 25). The best available information supports a conclusion that continued persistence of sea ice in the QEI is likely to continue to facilitate the subspecies' ability to migrate between the different islands up to the year 2080 (Jenkins et al. 2015, p. 4). The other extant subpopulation, the Banks Island group, now likely completes its life cycle on Banks Island. This subpopulation will not be as affected by long-term changes in sea ice. Overall, due to the continued persistence of sea ice in the QEI and the migration behavior of the caribou farther south, the effects of changes in sea ice on the Peary caribou will be limited.

The effects of climate change can also lead to changes in plant composition. The current trend suggests a decline in lichen availability and increase in vascular foliage (Chen
et a
l 2009a, pp. 19, 25-27). However, the increase in shrubs does not necessarily translate to an increase in the nutritional quality for the subspecies (COSEWIC 2015, p. 45).

As a subspecies listed as endangered under SARA, hunting of the Peary caribou is prohibited except when a permit is issued (Giroux et al. 2012, p. 4). For non-indigenous individuals, a permit can be issued if an activity is conducted for research, benefits the subspecies, or the subspecies affected is incidental to carrying out an activity (COSEWIC 2015, p. 52). Indigenous communities are excepted from this restriction for the purpose of exercising their harvesting rights, and coordination between these communities and provincial governments help set an annual quota. Additionally, local communities will sometimes ban hunting on certain years when the subspecies population is too low (COSEWIC 2015, p. 52). These continued collaborative efforts between national, provincial, and local communities in areas where the caribou populations seem to be stable suggest hunting of the Peary caribou is adequately regulated.

These factors (extreme weather events that cause mass starvation and death, changes in plant composition due to warming weather, loss of sea ice, small and isolated populations, synergistic and cumulative effects) affecting this subspecies are predicted to occur throughout its entire range with southern subpopulations experiencing a greater impact than subpopulations found farther north.

We evaluated all relevant threats, including any regulatory mechanisms and conservation measures addressing these threats. The primary threats are the effects of climate change on icing events and sea-ice loss. We find that overall sea-ice loss is projected to continue for the whole Canadian Arctic; however, this loss will not be as severe within the subspecies' range. Furthermore, recent presence and absence surveys have resulted in additional observations of the subspecies within its range.

In section 3(6), the Act defines an “endangered species” as any species that is “in danger of extinction throughout all or a significant portion of its range” and in section 3(20), defines a “threatened species” as any species that is “likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range.” While the subspecies has experienced previous population decline due to icing events, the population was able to rebound within two generations (COSEWIC 2015, p. vi). Additionally, reliable climate change models for the High Arctic where the subspecies is found project the likely persistence of sea ice during the winter time ensuring connectivity between the islands throughout the subspecies range out to the foreseeable future of 2050, even under high emission scenarios (Mallory and Boyce 2018, p. 2,197; Jenkins et al. 2015, p. 4). Continued migration between islands will allow the subspecies access to food resources during the wintertime thereby allowing the subspecies to withstand stochastic events caused by icing events. In addition, the continued presence of thick sea ice will also limit shipping traffic through the subspecies habitat. Lastly, continued management by Canadian governmental authorities in cooperation with local indigenous communities have limited the effects of hunting on the species. Overall, the Peary caribou consists of sufficient currently robust populations such that threats currently acting on the subspecies do not put it in danger of extinction. In addition, we conclude that the threats will not within the foreseeable future rise to the level where the subspecies is likely to no longer have sufficient robust populations. In other words, the subspecies is not likely to become endangered within the foreseeable future.

After evaluating threats to the species and assessing the cumulative effect of the threats under the section 4(a)(1) factors, we find that the effects of climate change and other potential threats, alone or in combination, do not rise to a level that causes this species to meet the definition of a threatened species or an endangered species throughout its entire range. Thus, after assessing the best available information, we conclude that Peary caribou is not in danger of extinction or likely to become so in the foreseeable future throughout all of its range.

Status Throughout a Significant Portion of Its Range

Under the Act and our implementing regulations, a species may warrant listing if it is in danger of extinction or likely to become so in the foreseeable future throughout all or a significant portion of its range. Having determined that the Peary caribou is not in danger of extinction or likely to become so in the foreseeable future throughout all of its range, we now consider whether it may be in danger of extinction or likely to become so in the foreseeable future in a significant portion of its range—that is, whether there is any portion of the species' range for which it is true that both (1) the portion is significant; and, (2) the species is in danger of extinction now or likely to become so in the foreseeable future in that portion. Depending on the case, it might be more efficient for us to address the “significance” question or the “status” question first. We can choose to address either question first. Regardless of which question we address first, if we reach a negative answer with respect to the first question that we address, we do not need to evaluate the other question for that portion of the species' range.

In undertaking this analysis for Peary caribou, we choose to address the status question first—we consider information pertaining to the geographic distribution of both the species and the threats that the species faces to identify any portions of the range where the species is endangered or threatened. We examined the following threats: Icing events, loss of sea ice, changes in plant composition, parasitic harassment, and shipping, including cumulative effects. For the Peary caribou, regional variations in threats are related to the latitudinal differences with the effects of climate change (sea-ice loss, icing events, and parasitic harassment) being greater on the southern subpopulations than on the northern subpopulation. Additionally, shipping traffic is more concentrated in the southern portion of the Canadian Arctic Archipelago. The cumulative effects of these threats mean that the four subpopulations of Peary caribou (Banks-Victoria islands, WQEI, EQEI, and Prince of Wales-Somerset-Boothia Peninsula) are experiencing different population trends and threat responses.

After experiencing population crashes in the 1990s due to icing events, the WQEI and EQEI now have stable or increasing population trends and now comprise 82 percent of the subspecies total populations (COSEWIC 2015, p. 41). Additionally, the northern portion of the Canadian Arctic archipelago contains the thickest sea ice in the Arctic region and this ice is replenished by multi-year flowing in from the Arctic Ocean (Li et al. 2020, p. 1; Howell et al. 2015, p. 1,623). The thickness of the sea ice around the Queen Elizabeth Islands contributed to shipping lanes being primarily located farther to the south (Engler and Pelot 2013, p. 9). The persistence of sea ice in this region allows the WQEI and EQEI Peary caribou subpopulations to be able to migrate between different islands. The continued ability to migrate between different islands will ensure the subspecies have access to sufficient food resources and help it recover from population fluctuations due to stochastic events. Overall, the stability as well as the previously noted lesser impact from threats related to climate change and shipping traffic for these most populous northern subpopulations suggests that the threats acting on these subpopulations do not rise to the level where the species is in danger of extinction or likely to become in danger of extinction within the foreseeable future.

While the two QEI subpopulations now have stable population trends, the Banks-Victoria island subpopulation and the Prince of Wales-Somerset-Boothia Peninsula island complex was experiencing a declining population trend. The Banks-Victoria island subpopulation also experienced a decline in the 1980s due to icing events. While the subpopulation in Victoria Island has yet to recover, the subpopulation on Banks Island has stabilized since 1992 albeit at a lower level (COSEWIC 2015, p. VI). Unlike the Queen Elizabeth Islands subpopulation discussed above, which regularly migrates between the smaller islands of the QEI, the Banks Island subpopulation, as suggested by the lack of outward gene flow, might not migrate

as often as other Peary caribou subpopulations (COSEWIC 2015, p. 26). This means that fluctuations in sea-ice level may not affect this subpopulation to the degree of other subpopulations of the Peary caribou. Therefore, the biggest threat affecting this subpopulation is likely to be icing events.

While icing events have and will continue to play a role in dramatic population crashes for this subpopulation, the population trend as noted above has remained stable since 1992 (COSEWIC 2015, p. 35). This overall trend persists despite an extreme weather event that took place in the Canadian Arctic Archipelago in 1996-1997 that resulted in a population crash of the WQEI subpopulation (COSEWIC 2015, p. 38; Jenkins et al. 2011, p. 120). Going into the foreseeable future, while climate models do project increases in the frequency and severity of icing events for Banks Island, there is greater uncertainty of the effect this will have on the population trend of this subpopulation (COSEWIC 2015, p. 47). Increased icing events could increase mortality, but reduced snow depth as a result of increases in temperature could result in greater access to foliage. That said, based on historical population trends, we have observed this subpopulation's ability to persist and rebound after an icing event, suggesting that it possesses sufficient ability to recover from stochastic icing events. This long-term stability leads us to conclude that while the Banks Island subpopulation might not return to its historical level, the threats acting on the subpopulation do not rise to the level where the species is in danger of extinction or likely to become in danger of extinction within the foreseeable future.

While the Banks Island subpopulation has stabilized, the Prince of Wales-Somerset-Boothia Peninsula islands complex is suspected to be near zero and may be extirpated due to a number of possible factors including wolf predation, extreme weather, hunting, and disease. The potential extirpation of this subpopulation warranted further consideration due to its potential effects on the subspecies as a whole. We next evaluated whether this subpopulation may be significant to the Peary caribou. The Service's most-recent definition of “significant” has been invalidated by the courts (
Desert Survivors
v.
Dep't of the Interior,
No. 16-cv-01165-JCS (N.D. Cal. Aug. 24, 2018)). Therefore, we evaluated whether the Prince of Wales-Somerset-Boothia subpopulation could be significant under any reasonable definition of “significant.” To do this, we evaluated whether this subpopulation may be biologically important to the species.

The Prince of Wales-Somerset-Boothia subpopulation contains very few individuals and may be extirpated. The decline or potential loss of this subpopulation will reduce the overall abundance of the subspecies and reduce its range. We do not have information on the genetic uniqueness of this subpopulation. That said, while the subspecies' genetic diversity will be affected by the decline of this subpopulation, historical genetic exchanges between this subpopulation and the other subpopulations mean this subpopulation is likely not genetically unique. The loss of this subpopulation would likely have a limited effect on overall genetic diversity. Overall, while the loss of this subpopulation would have some effect on the subspecies as a whole, it would likely be minimal, and the Peary caribou has historically experienced wide fluctuation in its overall population. In the past, other subpopulations experienced catastrophic die-off of up to 80 to 90 percent due to icing events and were able to recover within a few decades. This could allow other subpopulations to recolonize the island complex in the future. Therefore, because of the high number of individuals and the stability of other subpopulations as well as the potential for recolonization by those subpopulations, we determined that the Prince of Wales-Somerset-Boothia subpopulation is not biologically significant to the Peary caribou.

In summary, the species is not in danger of extinction or likely to become so in the foreseeable future in any significant portion of its range. Our approach to analyzing SPR in this determination is consistent with the court's holding in
Desert Survivors
v.
Department of the Interior,
No. 16-cv-01165-JCS, 2018 WL 4053447 (N.D. Cal. Aug. 24, 2018).

Determination of Status

Our review of the best available scientific and commercial information indicates that the Peary caribou does not meet the definition of an endangered species or a threatened species in accordance with sections 3(6) and 3(20) of the Act. Therefore, we find that listing the Peary caribou is not warranted at this time.

II. Proposed Listing Determination—Dolphin and Union Caribou

Background

Description

The Dolphin and Union caribou is a medium-sized caribou that is larger than the Peary caribou and smaller than the larger mainland barren-ground caribou. The pelage of Dolphin and Union caribou is slightly darker than that of the Peary caribou and lighter than the barren-ground caribou. Its winter coat is a distinctive white with a light-brown back and white legs. In the summer, the coat becomes darker brown on the back. This entity does not display the pronounced flank stripe typical of barren-ground caribou. Additionally, its antlers are much like that of a Peary Caribou and the antler velvet is pale gray, which is distinct from the dark brown antler velvet of mainland barren-ground caribou (SARC 2013, p. vi).

Taxonomy

The Dolphin and Union caribou has had a particularly confusing taxonomic history (COSEWIC 2011, p. 25). Most of the early taxonomic history of the Dolphin and Union caribou is identical to the Peary caribou. Therefore, this history can be found in the above section (Peary Caribou:
Taxonomy
).

In 2003, participants in a workshop on caribou taxonomy considered the existing classification to be insufficient to demonstrate the level of diversity that exists between the subspecies of caribou (McFarlane et al. 2003, pp. 127-128). The workshop concluded that conservation units should reflect the biodiversity and preserve the uniqueness of each caribou population in the Canadian Arctic Archipelago. They recommended the establishment of conservation units below the subspecies level to preserve the caribou (
Rangifer tarandus
) of the Canadian Arctic Archipelago (McFarlane et al. 2009, p. 105).

Several studies have postulated that Dolphin and Union caribou are genetically distinct from either the Peary caribou or the barren-ground caribou (McFarlane et al. 2013, pp. 124-126; Nagy et al. 2011, pp. 190, 194; Poole et al. 2010, p. 415). Dolphin and Union caribou have a high level of genetic distinctness (COSEWIC 2009, p. 117). Additionally, the Dolphin and Union caribou are genetically more related to the mainland populations than to the Peary caribou that occur on Victoria Island. However, the Dolphin and Union caribou are still genetically distinguished from both barren-ground caribou and Peary caribou (McFarlane et al. 2009, as cited in COSEWIC 2011, p. 25; McFarlane et al. 2003, pp. 124-126).

In May 2004, COSEWIC reassessed the status of the three Peary caribou populations and reviewed the designation. The 2004 assessment defined the Dolphin and Union population as separate from the Peary

caribou and from the barren-ground caribou and recommended a taxonomic revision of the Dolphin and Union population as
R. t. groenlandicus x pearyi
to distinguish the population from the mainland barren-ground caribou,
R. t. groenlandicus,
and from the Peary caribou,
R. t. pearyi
(McFarlane et al. 2013, pp. 124-126; Nagy et al. 2011, pp. 184, 190, 194; Poole et al. 2010, p. 415). While the 2004 COSEWIC report recommended the reclassification of the Dolphin and Union caribou, questions remained over whether the entity should be considered as a subspecies or a geographically distinct population.

In 2011, COSEWIC prepared to conduct a reassessment of all caribou in Canada; in preparation for the assessment, they published a document detailing “designatable units” (DU), geographically based areas created for management purposes, of caribou. A DU can be a species, subspecies, variety, or geographically or genetically distinct population that may be assessed by COSEWIC, where such units are both discrete and evolutionarily significant. In this assessment, COSEWIC confirmed the status of the Dolphin and Union population as a DU (COSEWIC 2011, pp. 10, 25). The Committee noted that the process of designating DUs takes into account taxonomy, phylogenetics, genetics, morphology, life history, and behavior of the species, as well as biogeographical information such as range disjunction and the ecogeography in which the species is found.

In its 2011 report, COSEWIC discussed the changes in taxonomy for the Dolphin and Union population and included the scientific name
R. t. groenlandicus x pearyi,
as distinct from the barren-ground caribou (
R. t. groenlandicus)
and from the Peary caribou population (
R. t. pearyi)
(COSEWIC 2011, entire). This classification does not mean that the Dolphin and Union subpopulation is of hybrid origin but is due to taxonomical ambiguity. The current classification then is a way for researchers to distinguish the Dolphin and Union subpopulation from the barren-ground caribou and the Peary caribou (Ray 2017, pers. comm.). However, this reclassification has not yet been formalized and the Dolphin and Union herd is currently classified as being part of the barren-ground caribou subspecies. Given the established taxonomic classification of the Dolphin and Union herd as part of
R. t. groenlandicus,
we evaluated whether the Dolphin and Union caribou represent a distinct population segment (DPS).

Evaluation of the Dolphin and Union Caribou Subpopulation as a Distinct Population Segment

Under section 3(16) of the Act, we may consider for listing any species, including subspecies, of fish, wildlife, or plants, or any DPS of vertebrate fish or wildlife that interbreeds when mature (16 U.S.C. 1532(16)). Such entities are considered eligible for listing under the Act (and, therefore, are referred to as listable entities), should we determine that they meet the definition of an endangered or threatened species.

Under the Service's DPS Policy (61 FR 4722, February 7, 1996), three elements are considered in the decision concerning the determination and classification of a possible DPS as threatened or endangered. These elements include:

(1) The discreteness of a population in relation to the remainder of the species to which it belongs;

(2) The significance of the population segment to the species to which it belongs; and

(3) The population segment's conservation status in relation to the Act's standards for listing, delisting, or reclassification (
i.e.,
is the population segment endangered or threatened).

A population segment of a vertebrate taxon may be considered discrete under the DPS policy if it satisfies either one of the following conditions:

(1) It is markedly separated from other populations of the same taxon as a consequence of physical, physiological, ecological, or behavioral factors. Quantitative measures of genetic or morphological discontinuity may provide evidence of this separation.

(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) of the Act.

If a population segment is considered discrete under one or more of the conditions described in the Service's DPS policy, its biological and ecological significance will be considered in light of Congressional guidance that the authority to list DPSs be used “sparingly” (see Senate Report 151, 96th Congress, 1st Session). In making this determination, we consider available scientific evidence of the DPS's importance to the taxon 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, this consideration of the population segment's significance may include, but is not limited to, the following:

(1) Persistence of the DPS in an ecological setting unusual or unique to the taxon;

(2) Evidence that loss of the DPS would result in a significant gap in the range of a taxon;

(3) Evidence that the DPS represents the only surviving natural occurrence of a taxon that may be more abundant elsewhere as an introduced population outside its historical range; or

(4) Evidence that the DPS 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 criteria, 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. Below, we summarize discreteness and significance for the Dolphin and Union caribou.

Discreteness

The Dolphin and Union caribou are markedly separate from other populations of the barren-ground caribou (
Rangifer tarandus groenlandicus).
Behaviorally, the Dolphin and Union caribou is a migratory population that calves on Victoria Island in the summer and winter on coastal tundra on the mainland. In other words, the Dolphin and Union caribou spends part of its life cycle on the mainland and the other part on an island. This is in contrast to the remainder of the subspecies that either spend their entire life cycles on the mainland or on an island. Mainland barren-ground caribou subpopulations migrate between the tundra and boreal forest habitats. Meanwhile, other barren-ground subpopulations (such as the ones on Baffin Island and Southampton Island) spend their entire life on an island (McFarlane et al. 2016, p. 2). In addition to behavioral differences, the Dolphin and Union caribou is also geographically isolated from other members of the subspecies during part of its life cycle. Although the subpopulation's range overlaps with other barren-ground caribou subpopulation during the wintering months on the mainland, while on Victoria Island, the Dolphin and Union

caribou is geographically isolated from other subpopulations of the barren-ground caribou on the mainland (McFarlane et al. 2016, p. 16).

Morphological and genetic discontinuities between Dolphin and Union caribou and other subpopulations of the barren-ground caribou provide further evidence of this separation. Morphologically, the Dolphin and Union caribou are smaller and lighter in color than the mainland barren-ground caribou (McFarlane et al. 2009, p. 125). Genetically, the Dolphin and Union caribou is more closely related to the mainland barren-ground caribou than other island caribous it shares Victoria Island with (McFarlane et al. 2009, p. 125). On the other hand, despite being more closely related, the Dolphin and Union caribou also maintains genetic distinctness from mainland subpopulations (McFarlane et al. 2016, pp. 8, 14; McFarlane et al. 2009, p. 125, Zittlau 2004, p. 113). Phylogenetic analyses conducted on mitochondrial DNA reveals that during the caribou recolonization of the Arctic at the end of the last Ice Age, the Dolphin and Union caribou diverged from the other barren-ground caribou subpopulations around approximately 3000 years ago (McFarlane et al. 2016, pp. 15-16).

In summary, we determine that the Dolphin and Union caribou is markedly separated from neighboring caribou subpopulations. At different times of the year, the Dolphin and Union caribou is physically (geographically) and reproductively isolated from the mainland subpopulations. The Dolphin and Union caribou also exhibit unique migratory behavior and genetic data supports the separation of the subpopulation from the barren-ground caribou. Therefore, we consider the Dolphin and Union caribou subpopulation to be discrete per our DPS policy.

Significance

We found that the Dolphin and Union caribou is significant to the
Rangifer tarandus groenlandicus
taxon because it differs markedly from other members in the taxon in its genetic characteristics.

The barren-ground caribou comprises multiple subpopulations found in the Yukon, Northwest Territories, and Nunavut (which includes Baffin Island and the islands of the Hudson Bay) (McFarlane et al. 2016, p. 2). The Dolphin and Union caribou is one of the few populations of the barren-ground caribou subspecies that uses both the islands of the Canadian Arctic Archipelago and the mainland as part of its range (Nagy et al. 2011, p. 2,342). As mentioned above, barren-ground caribou have three genetic variants: The mainland subpopulations, the Southampton Island subpopulations, and the Dolphin and Union caribou subpopulations. A study of allelic frequency shows that each subpopulation forms a unique cluster (McFarlane et al. 2016, p. 9), with the Dolphin and Union caribou being closer genetically to the mainland subpopulations than the Southampton subpopulation. This conclusion is further supported by a comparison of the fixation index (F
ST
value) between the multiple subpopulations including the Southampton, Dolphin and Union, and different mainland subpopulations that yielded similar conclusion (McFarlane et al. 2016, p. 9; McFarlane et al. 2014, p. 83). The F
ST
value for the Southampton subpopulation varies between 0.436 to 0.527. For the Dolphin and Union caribou, values vary between 0.059 and 0.067. For the mainland subpopulations, values vary between −0.004 (a calculation output that can be considered to be a zero) and 0.038. An F
ST
value of zero means that the two subpopulations being compared are genetically identical while a value of one suggests that it is possibly a different species. As can be seen here, the Southampton subpopulation has the highest level of genetic distinctness relative to the other two. While not as genetically distinct, the Dolphin and Union caribou still possess an F
st
value that is greater than the mainland subpopulations, by a large enough margin suggesting genetic distinctness from the rest of the subspecies (McFarlane et al. 2016, p. 9). This conclusion is supported by other publications which also identified the Dolphin and Union caribou as being distinct from all other mainland barren-ground caribou subpopulations (McFarlane et al. 2014, p. 83; Zittlau et al. 2009, as cited in COSEWIC 2011, p. 25; Zittlau 2004, p. 113).

In addition to their allelic differences, a study of the gene flow of the Dolphin and Union caribou supports the genetic distinctness of the subpopulation. Gene flow of the Dolphin and Union caribou appears to flow in a southward direction. That is, there is an outward flow of the Dolphin and Union caribou gene into neighboring mainland barren-ground caribou subpopulation located to the south of Victoria Island. However, there is a slower gene flow of the mainland barren-ground caribou into the Dolphin and Union caribou subpopulation (McFarlane et al. 2014, p. 88). This phenomenon can be explained by the behavioral difference between male and female caribous. While female caribous display site fidelity, male caribous tend to wander farther afield. Because female Dolphin and Union calve exclusively on Victoria Island, they are geographically isolated from mainland barren-ground caribou subpopulation (Nagy et al. 2011, p. 2,335). On the other hand, there is greater detection of first- and second-generation male migrants among other subpopulations of caribou (McFarlane et al. 2016, pp. 11, 14). This result suggests that some male Dolphin and Union caribou may migrate to other barren-ground caribou subpopulations resulting in outward gene flow. Additionally, there are periods of multiple years where the dispersal rate is zero meaning that there was no gene flow out of the subpopulation (McFarlane et al. 2016, p. 14). Overall, the gene flow patterns reinforce the genetic data, demonstrating that while there is occasional genetic exchange between Dolphin and Union caribou and the mainland barren-ground caribou subpopulations, the Dolphin and Union caribou maintains its genetic uniqueness.

This conclusion is supported by other studies that identified the genetic distinctness of Dolphin and Union caribou from other caribou subpopulations (McFarlane et al. 2014, pp. 82-83; McFarlane et al. 2009, p. 125; Zittlau 2004, p. 113). Additionally, the Dolphin and Union caribou experience geographic isolation on Victoria Island during calving season which contributes to a limited outward gene flow between the Dolphin and Union caribou and other populations of
Rangifer tarandus groenlandicus
(Nagy et al. 2011, p. 2,335). Although there are some genetic exchanges with the mainland barren-ground caribou through the migration of male Dolphin and Union caribou, the subpopulation geographic and genetic isolation likely contributed to its genetic uniqueness. Thus, we find that the Dolphin and Union caribou differs markedly from other populations of the species in its genetic characteristics.

Summary

Given that both the discreteness and the significance elements of the DPS policy are met for the Dolphin and Union caribou, we find that the Dolphin and Union caribou constitutes a valid DPS of
Rangifer tarandus groenlandicus.
Because we find the Dolphin and Union caribou subpopulation to be both discrete and significant, we evaluate whether this DPS is endangered or threatened based on the Act's definitions of those terms and a review of the factors listed in section 4(a) of the Act.

Life History

Dolphin and Union caribou have an average lifespan of 13-15 years. Males typically reach breeding age at around 4 years and females between 2-3 years (COSEWIC 2004, p. 28). Approximately 80 percent of females will have one calf annually; females will generally reproduce between the ages of 2 and 13 years and males between 4 and 13 years (Gunn et al. 1998, as cited in COSEWIC 2004, p. 28). The annual rut usually occurs in late autumn, and calving occurs in late spring, with variation depending on the latitude and environmental conditions (COSEWIC 2011, p. 11; Gates et al. 1986, pp. 216-222).

Calf production and recruitment of Dolphin and Union caribou are highly dependent on the female's physical condition, specifically their fat reserves (Cameron et al. 1992, p. 480). The nutritional condition of the female is dependent on the prevailing environmental conditions. As a result, there is high variability in annual pregnancy rate, calf production, and calf recruitment. Depending on the environment, pregnancy rates can vary from 0 to 100 percent. In severe winters, recruitment of calves can drop to 0 percent (COSEWIC 2004, pp. vii, 28). Under favorable conditions, roughly 50 percent of calves survive (Bergerud 1978, as cited in Miller et al. 2007, p. 25). In free-ranging caribou populations, the proportion of males to females averages 40 to 60 respectively (Miller et al. 2007, p. 25).

Range and Migration

The range of the Dolphin and Union caribou consists of Victoria Island and the Canadian mainland, covering a surface area estimated to be 499,449 km
2
(192,838mi
2
). That range crosses two Canadian territories: Nunavut and the NWT (SARC 2013, p. xiv; Governments of NWT and Nunavut 2011, p. 2; Poole et al. 2009, p. 415). Dolphin and Union caribou calve during the summer months on Victoria Island before moving south to the coast to rut. They then cross the sea ice of the Coronation Gulf, Dolphin and Union

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Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/fr%3A2021-18098. Public record. Not legal advice.