# Endangered and Threatened Wildlife and Plants; Threatened Species Status for the Olympia Pocket Gopher, Roy Prairie Pocket Gopher, Tenino Pocket Gopher, and Yelm Pocket Gopher, With Special Rule

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URL: https://www.frixlaw.com/law-library/documents/fr%3A2014-07414

## Record

- **Collection:** Federal Register
- **Document type:** Rule
- **Published:** April 9, 2014
- **Citation:** 79 FR 19760

## Text

DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[FWS-R1-ES-2012-0088; 4500030113]
RIN 1018-AZ17
Endangered and Threatened Wildlife and Plants; Threatened Species Status for the Olympia Pocket Gopher, Roy Prairie Pocket Gopher, Tenino Pocket Gopher, and Yelm Pocket Gopher, With Special Rule

AGENCY:

Fish and Wildlife Service, Interior.

ACTION:

Final rule.

SUMMARY:

We, the U.S. Fish and Wildlife Service (Service), determine threatened species status under the Endangered Species Act of 1973 (Act or ESA), as amended, for four subspecies of the Mazama pocket gopher found in Thurston and Pierce Counties of Washington State: The Olympia pocket gopher (
Thomomys mazama pugetensis
), Roy Prairie pocket gopher (
T. m. glacialis
), Tenino pocket gopher (
T. m. tumuli
), and Yelm pocket gopher (
T. m. yelmensis
). We are also promulgating a special rule under authority of section 4(d) of the Act that provides measures that are necessary and advisable for the conservation of the Mazama pocket gopher. The effect of this regulation is to add these subspecies to the list of Endangered and Threatened Wildlife, extend the Act's protections to these subspecies, and establish a 4(d) special rule for the conservation of the Olympia, Roy Prairie, Tenino, and Yelm pocket gophers.

DATES:

This rule becomes effective May 9, 2014.

ADDRESSES:

This final rule is available on the internet at
http://www.regulations.gov
and
http://www.fws.gov/wafwo/mpg.html
. Comments and materials we received, as well as some of the supporting documentation we used in preparing this rule, are available for public inspection at
http://www.regulations.gov
. All of the comments, materials, and documentation that we considered in this rulemaking are available by appointment, during normal business hours at: U.S. Fish and Wildlife Service, Washington Fish and Wildlife Office, 510 Desmond Drive, Lacey, WA 98503; telephone 360-753-9440, facsimile 360-534-9331.

FOR FURTHER INFORMATION CONTACT:

Ken S. Berg, Manager, Washington Fish and Wildlife Office, 510 Desmond Drive, Lacey, WA 98503, by telephone 360-753-9440, or by facsimile 360-534-9331. Persons who use a telecommunications device for the deaf (TDD) may call the Federal Information Relay Service (FIRS) at 800-877-8339.

SUPPLEMENTARY INFORMATION:

Executive Summary

Why we need to publish a rule.
Under the Act, a species may warrant protection through listing if it is endangered or threatened throughout all or a significant portion of its range. Listing a species as an endangered species or threatened species can only be completed by issuing a rule

This rule will
finalize the listing of the Olympia pocket gopher (
Thomomys mazama pugetensis
), Roy Prairie pocket gopher (
T. m. glacialis
), Tenino pocket gopher (
T. m. tumuli
), and Yelm pocket gopher (
T. m. yelmensis
) as threatened species under the Act. This rule also establishes a special rule under section 4(d) of the Act to provide for the conservation of the Mazama pocket gopher. Critical habitat for these four subspecies of the Mazama pocket gopher is published elsewhere in today's
Federal Register
.

The basis for our action.
Under the Act, we can determine that a species is an endangered or threatened species based on any of five 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. We have determined that the four Thurston/Pierce subspecies of the Mazama pocket gopher are negatively impacted by one or more of the following factors to the extent that each of these subspecies meets the definition of a threatened species under the Act:

• Habitat loss through conversion and degradation of habitat, particularly from development, successional changes to grassland habitat, military training, and the spread of woody plants;

• Predation;

• Inadequate existing regulatory mechanisms that allow the impacts of significant threats such as habitat loss; and

• Other natural or manmade factors, including small or isolated populations, declining population or subpopulation sizes, and control as a pest species.

We are promulgating a special rule.
We are exempting from the Act's take prohibitions (at section 9) certain activities that promote the maintenance or restoration of habitat conditions required by the Mazama pocket gopher consistent with regulations necessary and advisable for the continued conservation of the four subspecies (Olympia, Roy Prairie, Tenino, and Yelm pocket gophers). Specifically, the Service is promulgating a special rule under section 4(d) of the Act to exempt take of these listed species for general activities conducted on agricultural and ranching lands, regular maintenance activities on civilian airports, control of noxious weeds and invasive plants, maintenance of roadside rights-of-way, and limited activities on private landowner parcels. If an activity resulting in take of the Mazama pocket gopher is not exempted under this 4(d) special rule, then the general prohibitions at 50 CFR 17.31 for threatened wildlife would apply, and we would require a permit pursuant to section 10 of the Act for such an activity, as specified in our regulations. Nothing in this 4(d) special rule would affect the consultation requirements under section 7 of the Act. The intent of this special rule is to increase support for the conservation of the Mazama pocket gopher and provide an incentive for continued management activities that benefit the Olympia, Roy Prairie, Tenino, and Yelm subspecies and their habitat.

Peer review and public comment.
We sought comments from independent specialists to ensure that our designation is based on scientifically sound data, assumptions, and analyses. We invited these peer reviewers to comment on our listing proposal. We obtained opinions from two knowledgeable individuals with scientific expertise regarding the Mazama pocket gopher. These peer reviewers generally concurred with our methods and conclusions and provided additional information, clarifications, and suggestions to improve this final rule. Information we received from peer review is incorporated in this document. We also considered all comments and information received from the public during our three open comment periods, which were open a total of 135 days. We held two public information workshops and a public hearing on the proposed rule in April 2013.

Previous Federal Actions

The full candidate history and previous Federal actions for the Olympia, Roy Prairie, Tenino, and Yelm pocket gophers (hereafter referred to as “the four Thurston/Pierce subspecies of the Mazama pocket gopher”) are

described in the proposed rule to list, establish a 4(d) special rule, and designate critical habitat for these four subspecies, published December 11, 2012 (77 FR 73770). In that same proposed rule, we identified five subspecies of Mazama pocket gopher in the State of Washington for removal from the candidate list: The Olympic, Shelton, and Cathlamet pocket gophers (
Thomomys mazama melanops, T.m. louiei,
and
T.m. couchi,
respectively) because we determined that they are not warranted for listing; the Tacoma pocket gopher (
T.m. tacomensis
) because it is extinct; and the Brush Prairie pocket gopher (
T. talpoides douglasii
) because it was added to the list due to taxonomic error. We published a notice of availability of the draft economic analysis (DEA) of the critical habitat designation and announcement of public information meetings and a public hearing on our proposed rulemaking on April 3, 2013 (78 FR 20074), and a 6-month extension of the final determination for the proposed listing and designation of critical habitat for the four Thurston/Pierce subspecies of the Mazama pocket gopher on September 3, 2013 (78 FR 54218). We extended our final determination under section 4(b)(6)(B)(i) of the Act in response to substantial scientific disagreement surrounding the accuracy or sufficiency of available data regarding the degree of threat to the Mazama pocket gopher from various agricultural and ranching activities. We worked collaboratively with the Washington State Department of Agriculture (WSDA) during this extension to address these uncertainties to the extent possible.

Details regarding the comment periods on the proposed rulemaking to list the four Thurston/Pierce subspecies, promulgate a 4(d) special rule, and designate critical habitat are provided below. On September 3, 2013, we published a notice in the
Federal Register
affirming the removal of the Olympic, Shelton, Cathlamet, Tacoma, and Brush Prairie pocket gophers from the candidate list (78 FR 54214). Critical habitat for the Olympia, Roy Prairie, Tenino, and Yelm subspecies of the Mazama pocket gopher is published separately elsewhere in today's issue of the
Federal Register
.

Summary of Comments and Recommendations

We requested written comments from the public on the proposed listing, the associated 4(d) special rule, and the designation of critical habitat for the four Thurston/Pierce subspecies of the Mazama pocket gopher during three comment periods. The first comment period, associated with the publication of the proposed rule (77 FR 73770; December 11, 2012), was open for 60 days, from December 11, 2012, through February 11, 2013. We then made available the DEA of the proposed critical habitat designation and reopened the comment period on the proposed rule for an additional 30 days, from April 3, 2013, to May 3, 2013 (78 FR 20074; April 3, 2013). We also contacted appropriate Federal, State, tribal, county, and local agencies; scientific organizations; and other interested parties and invited them to comment on the proposed rule and the DEA. We held two public information workshops and a public hearing in April 2013 on the proposed rule to list the subspecies, the associated 4(d) special rule, and the proposed critical habitat designations. On September 3, 2013, we announced a 6-month extension of the final determination on the listing and critical habitat designation for the four Thurston/Pierce subspecies of the Mazama pocket gopher (78 FR 54218) and reopened a third comment period on the proposed rule to list, establish a 4(d) special rule, and designate critical habitat for the four Thurston/Pierce subspecies for an additional 45 days. The total time available for public comment on the proposed rulemakings for the four Thurston/Pierce subspecies of the Mazama pocket gopher was 135 days.

During the 3 public comment periods, we received close to 220 comment letters and emails from individuals and organizations, as well as speaker testimony at the public hearing held on April 18, 2013. These comments addressed the proposed listing and associated special rule, or the proposed critical habitat (or both) for Mazama pocket gopher. We received comment letters from two peer reviewers, one State agency, and two Federal agencies on these four subspecies of the Mazama pocket gopher. The final rule designating critical habitat for the four Thurston/Pierce subspecies of the Mazama pocket gopher is published separately elsewhere in today's volume of the
Federal Register
, and comments specific to the critical habitat are addressed in that rulemaking. Here we address only those comments relevant to the proposed listing and the associated special rule under section 4(d) of the Act.

All substantive information provided during comment periods has either been incorporated directly into this final rule or is addressed below. Comments we received are grouped into general issues specifically relating to the listing or 4(d) special rule for the four Thurston/Pierce subspecies of the Mazama pocket gopher, and are addressed in the following summary and incorporated into the final rule as appropriate.

Comments From Peer Reviewers

In accordance with our peer review policy published on July 1, 1994 (59 FR 34270), we solicited expert opinion from six knowledgeable individuals with scientific expertise that included familiarity with the Mazama pocket gopher and its habitats, biological needs, and threats. Two peer reviewers responded, and both were supportive of the Service's evaluation of the best scientific and commercial data available in proposing to list the four Thurston/Pierce subspecies of the Mazama pocket gopher. Our requests for peer review are limited to a request for review of the merits of the scientific information in our documents; if peer reviewers have volunteered their personal opinions on matters not directly relevant to the science of our proposed listing, we do not respond to those comments here.

(1)
Comment:
Both peer reviewers provided corrections and suggestions for clarifying and improving the accuracy of the Background, Habitat and Life History, Historical and Current Range and Distribution, Summary of Factors Affecting the Species, and Conservation Measures sections of the preamble of the proposed rule.

Our Response:
We appreciate these corrections and suggestions, and have made changes to this final rule to reflect the peer reviewers' input.

(2)
Comment:
One peer reviewer recommended that an education and incentives program be implemented for private landowners to help conserve the four Thurston/Pierce subspecies of the Mazama pocket gopher.

Our Response:
The Service supports a variety of programs that conserve species, including Habitat Conservation Planning and Safe Harbor Agreements. The Service is working with the Natural Resources Conservation Service (NRCS), Thurston County, Washington Department of Fish and Wildlife (WDFW), and various nongovernmental entities to develop and implement education and incentive programs for the four Thurston/Pierce subspecies of the Mazama pocket gopher. We appreciate the suggestion, and will keep this in mind as we move forward with recovery planning for these species. However, such a consideration is not directly relevant to our evaluation of the status of the species.

(3)
Comment:
One peer reviewer found the section on unauthorized collecting, handling, possessing, etc., to

be confusing where it referenced possession of specimens not more than 100 years old but collected prior to 2012.

Our Response:
We have deleted this section because it did not accurately describe the Act's prohibitions. However, we can clarify for the reviewer that possession of specimens collected prior to listing is not prohibited.

Comments From State

Section 4(i) of the Act states, “the Secretary shall submit to the State agency a written justification for his [her] failure to adopt regulations consistent with the agency's comments or petition.” Comments we received from State agencies regarding the proposal to list four Thurston/Pierce subspecies of the Mazama pocket gopher subspecies as threatened under the Act are addressed below. We received comments from WDFW, Washington Department of Natural Resources (WDNR), and Washington State Department of Transportation (WSDOT) related to biological information, threats, and the 4(d) special rule.

WDFW and WDNR provided a number of recommended technical corrections or edits to the proposed listing determination for the four Thurston/Pierce subspecies of the Mazama pocket gopher. We have evaluated and incorporated this information into this final rule where appropriate to clarify the final listing determination. In instances where the Service may have disagreed with an interpretation of the technical information that was provided, we have responded in separate communication with either WDFW or WDNR.

Washington Department of Fish and Wildlife

(4)
Comment:
WDFW noted that no citation was given for the list of soils we described as being occupied by the Mazama pocket gopher in Washington.

Our Response:
The list of soil types described in the proposed rule were compiled by using the WDFW Heritage Database to document where occurrence records of the Mazama pocket gopher overlapped mapped soil type. While not all USDA soil type descriptions include slope, the majority of soil types where slope was included were described as being below 15 percent.

(5)
Comment:
WDFW stated that it is important to consider that pocket gopher populations are known to fluctuate and that those fluctuations may be fairly large.

Our Response:
The Service agrees that some species of pocket gophers that live multiple years and undergo multiple reproductive cycles per year are likely to exhibit fairly large fluctuations in population number, but we point out the following: All of the data we currently have indicates that Mazama pocket gophers are short lived (1-2 years), have a single reproductive event per year, and average five young. If predation and disease pressures are low and reproductive success is high, this could result in a fairly large population increase, but without the means to monitor population numbers, it is a difficult assertion to either support or disprove. Since there is only a weak correlation between the number of pocket gopher mounds and the number of resident pocket gophers (Olson 2011a, p. 37), and since there are many different scenarios under which an individual pocket gopher may increase the number of mounds it makes (optimal foraging, re-excavation, new excavation, etc.), the Service believes it is currently impossible to document fluctuations in population size. In arriving at our determination that the four Thurston/Pierce subspecies of the Mazama pocket gopher meet the definition of “threatened” under the Act, we note our conclusion is not based on estimates of population size, but on the reduction in range and numbers of populations due to past threats, and the negative impact of ongoing threats to those few populations that remain. We discuss this further in our response to Comment 15, below.

(6)
Comment:
WDFW suggested clarifications to the list of allowed activities on airports and on single-family residential properties under the proposed 4(d) special rule. WDFW expressed the concern that any special rules pertaining to airports be carefully crafted, and that there should be a mechanism in place to monitor Mazama pocket gophers on all occupied airports as they will face increasing pressure from surrounding development over time.

Our Response:
We have amended the 4(d) special rule to clarify the list of allowed activities that are covered. The Mazama pocket gopher special rule that pertains to civilian airports has been reworded based on input from a variety of commenters, including the Port of Olympia and informal comments submitted by the Federal Aviation Administration (FAA). We believe our final 4(d) special rule addresses concerns and incorporates recommendations we received on our proposal, and exempts from the prohibitions of section 9 certain ongoing activities on civilian airports and residential properties consistent with regulations necessary and advisable for the continued conservation of the four Thurston/Pierce subspecies of the Mazama pocket gopher. However, we note 4(d) rules can be revoked or amended through rulemaking at any time should the Service determine that they are no longer consistent with the conservation of the species.

While the Service did not list the Shelton pocket gopher (
Thomomys mazama couchi;
September 3, 2013, 78 FR 54214), which largely resides on the Port of Shelton's Sanderson Field (also known as Shelton Airport), it remains a State-listed species and as such, the Port of Shelton will be required to continue to conserve the species on their property. If the status of the Shelton pocket gopher changes such that Federal listing may be warranted, the Service retains discretion to propose listing this subspecies.

Washington Department of Natural Resources

(7)
Comment:
WDNR, as well as the Natural Resources Conservation Service (NRCS), suggested additions and changes to the list of allowed agricultural activities and a revision to the calendar dates that some of those activities may take place under the proposed 4(d) special rule. They suggested these changes in order to avoid possible unintended consequences of some of the proposed requirements, which they believe might compromise the goal of encouraging continued agricultural use of these areas. WDFW raised concern about the lack of restrictions on conversion from one agricultural use to another, since Mazama pocket gophers do not respond positively to all agricultural practices.

Our Response:
The Service worked closely with our State and Federal partners to understand which agricultural practices and related activities could be covered under the 4(d) special rule. Not all suggested changes were incorporated because not all activities that were suggested met our criteria for what is appropriate for inclusion under a 4(d) special rule for the four Thurston/Pierce subspecies of the Mazama pocket gopher (under section 4(d) of the Act, such a special rule must be “necessary and advisable for the conservation of the species”). We have amended the rule to clarify the terms used, revised the dates that covered activities are allowed, and revised the list of agricultural activities that are covered, where appropriate. We believe our final 4(d) special rule addresses concerns and incorporates recommendations we received on our proposal and exempts from the

prohibitions of section 9 certain ongoing agricultural practices consistent with regulations necessary and advisable for the continued conservation of the four subspecies of Mazama pocket gopher. With the help of our Federal and State partners, we will continue to work with agricultural landowners as necessary to more fully cover their activities while conserving the Mazama pocket gopher using a range of available conservation tools, such as permits and other authorizations (see also our response to Comment 38).

Washington State Department of Transportation

(8)
Comment:
WSDOT asked that we consider expanding the exemptions listed under our 4(d) special rule to include vegetation management of roadside rights-of-way, including mechanical mowing, weed control, and woody vegetation control (mechanical or herbicide control measures), as well as fencing operations. They pointed out that these activities maintain suitable habitat conditions for the pocket gophers by reducing the woody vegetation that they avoid, and maintaining the low vegetation cover that they favor. The agency additionally pointed out that suitable habitat for the Mazama pocket gopher is found along highways and roadways that traverse prairie habitats throughout Thurston and Pierce Counties.

Our Response:
We agree that the roadside management activities described by WSDOT benefit the Mazama pocket gopher by restoring or maintaining habitat in a condition suitable for the subspecies. As we do not wish to discourage the continuation of proactive management activities that benefit the conservation of the Mazama pocket gopher, as described in the Special Rule section of this document, we conclude that it is necessary and advisable for the conservation of the four Thurston/Pierce subspecies to add roadside vegetation management and fencing activities to the list of exemptions from section 9 in our 4(d) special rule. This exemption applies to all Federal. State, county, private, or Tribal vegetation management activities on highways or roadside rights-of-way. Under the 4(d) special rule, although exemptions from the prohibitions of section 9 are provided, any activities subject to a Federal nexus and that may affect the species or its critical habitat still require consultation under section 7 of the Act.

Comments From Federal Agencies

Natural Resources Conservation Service

Comments from the NRCS have been incorporated into Comment 7, above.

Comments From the Public

(9)
Comment:
Several commenters questioned the use of the current taxonomy for the Mazama pocket gopher for the purposes of listing.

Our Response:
The Service acknowledges that the original taxonomy of the Mazama pocket gopher was based on morphotype (the difference between the appearances of separate subspecies) and that the examination of genetic material would provide greater insight into the degree of relatedness between subspecies. However, under the Act we are to make a listing determination based on the best scientific and commercial data available at the time of our rulemaking; we cannot speculate as to what future research may or may not reveal. The currently accepted subspecific designations of
Thomomys mazama
(the Mazama pocket gopher) stand according to the accepted rules of the International Commission on Zoological Nomenclature. No compelling information is available nor has been submitted through the appropriate scientific channels necessary to effect a revision in the established taxonomy. Some genetic work conducted on the Mazama pocket gopher created confusion regarding their taxonomy, but that work was never published in a peer-reviewed journal.

It is possible that ongoing genetic work will clarify the relationship between the subspecies in the future, and if the International Commission on Zoological Nomenclature receives and accepts a revised taxonomy for the Mazama pocket gopher that is at odds with the taxonomy used here, we can revisit the listing at that time. To date, however, there has been no publication of any data that could lead to a formal submission for a revision of the taxonomy of the Mazama pocket gopher to the International Commission on Zoological Nomenclature, nor is there any record indicating that they have received any petition to consider a revision. Therefore, consistent with the direction from the Act (i.e., based on the best scientific and commercial data available at the time of our finding), we are using the established taxonomy for the Mazama pocket gopher, which recognizes the Olympia, Roy Prairie, Tenino, and Yelm pocket gopher as separate subspecies. See the “Taxonomy” section of this document for further information.

(10)
Comment:
Several commenters believed that an ongoing collaboration between the U.S. Geological Survey (USGS) and the Service is designed to definitively determine whether or not the present subspecies distinctions upon which the proposed listing relies are in fact scientifically accurate, and believed the Service should delay its listing determination until these results are completed.

Our Response:
Scientific knowledge is an ever-growing body of work to which many researchers and studies contribute. There is no one point in time at which “science” is complete, however, the Service is required to use “the best scientific and commercial data available” at the time a listing determination is made. The ongoing collaboration between USGS and the Service that was referenced by the commenters was designed to assist in the ongoing conservation of the four Thurston/Pierce subspecies of the Mazama pocket gopher, and was not intended to support a determination of whether or not listing them as threatened under the Act is warranted. The results of this study would allow the Service to establish: (a) The functional unit of management for the species (e.g., the subspecies level, the metapopulation level, or the population level); and (b) where the physical boundaries for those units exist on the landscape. This assessment will be made based on whether or not the results indicate genetic differentiation has resulted in evolutionarily divergent paths for different populations. Evidence of evolutionary divergence will dictate the future management strategies for the Mazama pocket gopher. This is not the same question as whether the evidence suggests a possible redefinition of subspecies, though that could be a logical outgrowth of the research conducted if the results support that outcome. See also our response to Comment 9, above.

(11)
Comment:
One commenter stated that the presumption of earlier expansive occupancy for the Mazama pocket gopher across undeveloped prairies is without merit.

Our Response:
It is impossible to know for certain the full extent of the historical occupancy for the Mazama pocket gopher in Washington State for the entirety of the species' evolutionary history. Extrapolating from the geologic record, we can reasonably assert that pocket gophers were more widespread and likely occupied a much wider range of habitats across a much broader area prior to the descent of the Vashon lobe of the Cordilleran ice sheet during the last glaciation period. This is

demonstrable through the isolated and genetically distinct population of Mazama pocket gopher in the Olympic Mountains and other isolated populations, such as the Cathlamet pocket gopher in western Washington. Pocket gophers simply cannot disperse quickly across great distances where habitat is discontiguous, indicating that the ability of populations to extend across the state over a short period of time would have been extremely improbable. In order for prehistoric pocket gopher populations to reach the Olympic Mountains, they would have had to have had a much wider distribution across a greater variety of habitats than they currently inhabit. Mazama pocket gophers, as we know them, have evolved to require friable, well-drained soils in relatively open areas. The prairies of the south Puget Sound landscape are exactly that.

Considering the potential for evolutionary adaptation on the geologic time scale, it is completely reasonable to expect that pocket gopher populations were historically far more widespread in western Washington. That said, all species are somewhat patchily distributed based on habitat availability and each species' ability to disperse to, compete for, and exploit resources, so it is possible some historical prairies or areas of prairies may never have been occupied. We further acknowledge here and elsewhere in this document that the Mazama pocket gopher exhibits patchily distributed use of available habitat, meaning that not all suitable areas are likely to be occupied at all times. The current fragmented and discontiguous state of apparently suitable habitat, such as the remaining undeveloped prairies, has rendered it impossible for the Mazama pocket gopher to sustain widespread occupancy, as the Service asserts was likely the case. It is reasonable to state, based on knowledge of dispersal capability, current distribution, and the distribution of similar
Thomomys
species, that the Mazama pocket gopher likely had a much broader historical distribution that included a greater portion of the prairie habitat in the south Puget Sound than they currently occupy, as did Dalquest and Scheffer (1942, p. 95; 1944a, p. 311).

(12)
Comment:
One commenter stated that the only distribution studies being conducted on the Mazama pocket gopher involved lands within the Thurston County Urban Growth Areas (UGAs), and believed Mazama pocket gophers exist in many other areas of the County.

Our Response:
We draw the commenter's attention to the WDFW (2013a) Mazama Pocket Gopher Distribution and Habitat study, which used a randomized design to sample approximately 800 locations in Grays Harbor, Lewis, Mason, Pierce, and Thurston Counties on public and private lands, the vast majority of which were outside of any UGA. We also note that this study reinforced the current known distribution of the Mazama pocket gopher in western Washington by providing insight into where Mazama pocket gopher sign was detected (positive survey data) and where it was not detected (negative survey data). The strength of this effort and its results support our current understanding of the distribution of the Mazama pocket gopher in Thurston County.

(13)
Comment:
Two commenters referenced the reports from contract biologists who claim to have found Mazama pocket gopher mounds outside of the currently known range.

Our Response:
The Service took these reports into consideration, but subsequent trapping conducted by WDFW at the sites in question have resulted in the capture of only moles (
Scapanus
spp.), whose mounds are often confused with those of Mazama pocket gophers. Neither Service nor WDFW biologists have been able to locate any other Mazama pocket gopher sign in the area despite broad survey efforts.

(14)
Comment:
Several commenters expressed the opinion that the distribution and population sizes currently known for the Mazama pocket gopher have been underestimated, while another commenter stated that populations are either stable or increasing. Several other commenters stated that the Mazama pocket gopher should not be given Federal protection under the Act when it appears as if they occur in great numbers.

Our Response:
The extensive distribution study recently conducted by WDFW (2013a) reinforced the known distribution of the Mazama pocket gopher in Washington State and provided valuable “negative” survey data by documenting areas where Mazama pocket gophers were not detected. It is important to note that the Service did not use population size while conducting the threats analysis because there is no established way to accurately estimate and monitor population size for the Mazama pocket gopher. No data were collected that would provide information about population trends, nor would it have been possible to obtain this data in a single survey season.

Very few people actually see Mazama pocket gophers because they are primarily fossorial, living almost entirely underground. What most people see when they become aware of pocket gophers are mounds of dirt excavated from the tunnel systems where the pocket gophers live, and they may extrapolate from the number of mounds to the number of gophers, assuming that many mounds equates to many gophers. Research has demonstrated that the correlation between the number of mounds and the number of pocket gophers is weak (Olson 2011a, p. 37), and there are many different circumstances that can lead to an increase in the number of mounds when there are not many gophers. Such circumstances include instances of soil compaction (a response to tunnels being crushed or damaged), in cases of sparse vegetation (which forces the animals to dig farther for forage material), or when gophers disperse into a new area and have to excavate a completely new tunnel system.

Since Mazama pocket gophers are extremely territorial, their density is low except when young are present. Another complicating factor is that Mazama pocket gophers and moles can coexist at the same site, creating the impression that there are many more gophers than actually occur. There is currently no effective and accurate way to count live pocket gophers. However, the Service did determine larger-scale changes in population status such as local extirpations and range contractions, and evaluated potential future status in the threats analysis section of this rule for the four Thurston/Pierce subspecies of the Mazama pocket gopher by focusing on factors such as habitat destruction and fragmentation, predation, and lack of gene flow between extant populations. Based on our evaluation of these considerations, we have concluded that each of the four Thurston/Pierce subspecies of the Mazama pocket gopher meets the definition of a threatened species under the Act.

(15)
Comment:
One commenter questioned whether or not there was a reduction in population numbers of the Mazama pocket gopher in Washington and asserted that if a decrease in population numbers does exist, it should be attributed to past pest control efforts, of which Mazama pocket gophers were a target as recently as 1992. The same commenter stated that Mazama pocket gophers are “rodents,” implied that rodents are immune to the efforts of humans to eradicate them, and provided a list of documents reporting on efforts to control or eradicate many different species of
Thomomys
and many subspecies of
T. mazama.
Most of

these studies were conducted in Oregon and where gophers were considered pests at tree farms.

Our Response:
Because there is currently no practical way to count individual Mazama pocket gophers within a population, the status evaluation of each subspecies was conducted using other metrics. The Service determined that the suitable habitat available has been reduced to the point that many historical populations have been permanently extirpated (such as in heavily developed areas) and gene flow between surviving populations has been restricted to the point of preventing the natural recovery of the subspecies. Past pest control efforts directed at Mazama pocket gophers may have contributed to fragmentation and decline in some populations.

While it is true that Mazama pocket gophers are rodents, it is important to note that the documented reproductive strategy of Mazama pocket gophers is unlike that of most rodents. Mazama pocket gophers only reproduce once a year and have an average lifespan of just a year or two in the wild. Even though they generally have a litter of around five pups, they are still a prey species, so it is reasonable to expect that only one or two of their offspring will survive each year, depending on contemporaneous predation pressure. This life history is in contrast to most other rodents, many of which have flexible reproductive cycles and the ability to produce multiple large litters of offspring each year.

Even within the same species of pocket gopher, evolutionary adaptation plays a role in the ability of individual subspecies to utilize particular habitats. The majority of the subspecies of
Thomomys mazama
in Washington inhabit soils associated with prairies and glacial outwash, not forests. Douglas-fir trees (
Pseudotsuga menziesii
) will encroach into the soil types and prairies that the four Thurston/Pierce subspecies of the Mazama pocket gopher prefer, but Mazama pocket gopher habitat in Washington historically consisted of open areas. To extrapolate from the literature regarding other species of
Thomomys
and even from other subspecies of
T. mazama
that live in different habitat types could lead to erroneous conclusions about the ability of the four Thurston/Pierce subspecies of the Mazama pocket gopher to persist without protection.

(16)
Comment:
Many commenters with concerns about the listing of the Mazama pocket gopher conflated the U.S. Fish and Wildlife Service (the Service) with the Washington Department of Fish and Wildlife (WDFW), which is the State of Washington's fish and wildlife management agency.

Our Response:
While the Service, as a Federal agency, works collaboratively with the State of Washington and maintains close working relationships with their expert biologists, we cannot speak to the agreements negotiated between WDFW and other parties, except where we explicitly rely upon information in those agreements, nor are we able to account for any perceived inconsistencies in information produced by the State. It is especially important to recognize that a conservation agreement negotiated between State agencies, such as WDFW, and independent parties is not automatically extended to include the Service or accepted by the Service, regardless of the conservation benefit to the species.

(17)
Comment:
Several commenters observed that WDFW clarified their position on the necessity of a Federal listing for the Mazama pocket gopher between the first comment period and the second comment period.

Our Response:
The Service received two comment letters from WDFW during the public comment periods. WDFW initially stated, “While WDFW supports the objective of ensuring appropriate conservation measures are in place for the species, federal listing and critical habitat designation is not necessary at this time due to ongoing county, state, and federal conservation efforts.”

During the second comment period, the Director of WDFW submitted a second comment letter that stated, in part “The GMA [Washington State's Growth Management Act] provides landscape-scale planning and conservation policies and tools, while the ESA focuses on protection for species and the ecosystems upon which they depend. Each authority plays an important role in achieving our shared goals for prairie habitat and species conservation; however, in this case implementation to date of GMA alone has not provided enough certainty of future conservation for the species to fully address the threats identified in the proposed federal ESA listing. More work is needed to identify specific protection standards at the landscape and site scale in order to achieve those goals. Policy makers and planners continue to work together to identify these standards so that we can work together jointly to help other entities prepare for these potential listings, and perhaps eliminate the need for additional listings in the future due to the presence of sufficient state-led conservation actions.”

(18)
Comment:
Several commenters mistakenly used the term “endangered” instead of “threatened” to refer to the Service's proposed listing status of the four subspecies of the Mazama pocket gopher found in Pierce and Thurston Counties.

Our Response:
An “endangered” species is any species that is in danger of extinction throughout all or a significant portion of its range; a “threatened” species is any species that is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range. Endangered species are at the brink of extinction today, while threatened species are likely to be at the brink in the near future if their status does not improve or at least stabilize. We have made the determination that the four Thurston/Pierce subspecies of the Mazama pocket gopher found in Pierce and Thurston Counties are likely to become an endangered species in the foreseeable future, therefore each will be listed as a “threatened” species under the Act.

(19)
Comment:
Many commenters questioned the data and the science used to determine the threatened status of the four Thurston/Pierce subspecies of the Mazama pocket gopher, averring that the state of our collective knowledge about the Mazama pocket gopher and its known threats is incomplete and that more studies are required to make a determination.

Our Response:
We are required to make our determination based on the best scientific and commercial data available at the time of our rulemaking, except in cases where the Secretary finds that there is substantial disagreement regarding the sufficiency or accuracy of the available data relevant to the determination. In such a case, under section 4(b)(6)(B)(i) of the Act, the Secretary may extend the 1-year period to make a final determination by up to 6 months for the purposes of soliciting additional data. In this case, we did extend our final determination on the listing status of the four Thurston/Pierce subspecies of the Mazama pocket gopher by 6 months due to substantial disagreement regarding the sufficiency or accuracy of some of the available threats information, which is the maximum extent allowable under the statute. We considered the best scientific and commercial data available regarding the subspecies of Mazama pocket gophers and their habitats in Washington State to evaluate their potential status under the Act.

In the case of the Olympic pocket gopher (
Thomomys mazama melanops
), the Shelton pocket gopher (
T. m. couchi
), and the Cathlamet pocket gopher (
T. m. louiei
), we determined that the best available data did not support listing under the Act (September 3, 2013; 78 FR 54214). For the Olympia pocket gopher, Roy Prairie pocket gopher, Tenino pocket gopher, and Yelm pocket gopher, as detailed in the Summary of Factors Affecting the Species section of this document, our evaluation of the best available scientific data leads us to determine that these subspecies each meet the definition of a threatened species under the Act. We solicited peer review of our evaluation of the available data, and our peer reviewers supported our analysis. Science is a cumulative process, and the body of knowledge is ever-growing. In light of this, the Service will always take new research into consideration. If plausible new research supports amendment or revision of this rule in the future, the Service will modify the rule consistent with the Act and our established work priorities at that time.

(20)
Comment:
Several commenters suggested that the Service did not take into account WDFW's ongoing research that had not been formally completed when the proposed rule was published.

Our Response:
The Service was fully informed by the researchers who were conducting this work and cited data provided by those individuals directly where their current state of knowledge differed from their previously published reports. WDFW's January 2013 summary report of the extensive Mazama pocket gopher distribution and habitat survey that was conducted in 2012 reinforced the known distribution of Mazama pocket gophers in Washington State. The report stated that only one potentially new location had been identified, but subsequent investigation did not result in confirmation of pocket gopher presence at that site. The WDFW survey was a valuable contribution to our current state of knowledge about Mazama pocket gopher distribution and habitat use in that it provided both positive and negative survey data that reinforced the previously established pattern of distribution.

(21)
Comment:
One commenter requested substantiated data demonstrating a positive benefit of listing the Mazama pocket gopher, and asked whether there had been an evaluation of the economic impact of the pending action.

Our Response:
In making a determination as to whether a species meets the Act's definition of an endangered or threatened species, under section 4(a)(1)(A) of the Act the Secretary is to make that determination based
solely
on the basis of the best scientific and commercial data available (emphasis added). The question of whether or not there may be some positive benefit to the listing cannot by law enter into the determination. The evaluation of economic impacts comes into play only in association with the designation of critical habitat under section 4(b)(2) of the Act, as described in detail in our final designation of critical habitat for Mazama pocket gopher, published elsewhere in the
Federal Register
today. Therefore, although we did not consider the economic impacts of the proposed listing, as such a consideration is not allowable under the Act, we did consider the potential economic impacts of the critical habitat designation, including the potential benefits of such designation.

(22)
Comment:
Numerous commenters expressed concerns that the listing of the four Thurston/Pierce subspecies of the Mazama pocket gopher would result in sweeping adverse economic impacts. Among these concerns was that much of the privately owned land and housing would be rendered worthless, and that businesses would be ruined. One commenter expressed concerns that their property would be sold to developers, or that there would be no compensation for property that would be rendered unusable. Several commenters expressed concerns that restrictions associated with the listing would hinder economic development, and implied that the uncertainty associated with the listing could hinder the ability to pass bonds for school construction.

Our Response:
We understand that there is a lot of confusion and concern about the effect of a listing and critical habitat designation for the four Thurston/Pierce subspecies of the Mazama pocket gopher. We encourage any landowners with a listed species present on their property and who thinks they carry out activities that may negatively impact that listed species to work with the Service. We can help those landowners determine whether a habitat conservation plan (HCP) or safe harbor agreement (SHA) may be appropriate for their needs. These plans or agreements provide for the conservation of the listed species while providing the landowner with a permit for incidental take of the species during the course of otherwise lawful activities. We are working with Thurston County to develop a county-wide HCP for grassland and prairie associated species, including the Mazama pocket gopher. If completed, this HCP would provide long-term regulatory assurances under the Act for people who live, work, or conduct business in Thurston County.

In addition, we have attempted to recognize the conservation contribution of non-Federal landowners through the issuance of a 4(d) special rule, which exempts individuals from the take prohibitions of the Act for certain activities, such as the construction of dog kennels or installation of fences or play equipment on their property. The 4(d) special rule additionally identifies specific agricultural practices, noxious weed and invasive plant control, and roadside maintenance activities that are consistent with regulations necessary and advisable for the continued conservation of the Mazama pocket gopher.

We also note that any restrictions or regulations already in place for the Mazama pocket gopher and its habitat and any costs associated with those restrictions or regulations under the GMA and associated critical areas ordinances were not the result of listing under the Act, but are a consequence of State laws and regulations that were already in place. We acknowledge that some economic impacts are a possible consequence of listing a species under the Act; for example, there may be costs to the landowner associated with the development of an HCP. In other cases, if the landowner does not acquire a permit for incidental take, the landowner may choose to forego certain activities on their property to avoid violating the Act, resulting in potential lost income. However, as noted in our response to Comment 21, above, the statute does not provide for the consideration of such impacts when making a listing decision. Section 4(b)(1)(A) of the Act specifies that listing determinations be made “solely on the basis of the best scientific and commercial data available.” Such costs are therefore precluded from consideration in association with a listing determination.

The Act does provide for the consideration of potential economic impacts in the course of designating critical habitat. However, the regulatory consequence of critical habitat designation is limited to actions with a Federal nexus (activities that are funded, authorized, or carried out by a Federal agency). The designation of critical habitat has no regulatory effect on private lands lacking a Federal connection. Critical habitat designation itself does not prevent development or alteration of the land, create a wildlife preserve, or require any sort of response or management from a private

landowner. Therefore, the designation of critical habitat would not directly result in any specific requirements by the Federal Government on the part of private landowners. Even in the case of a Federal nexus, such as in a case where a private landowner should require a Federal permit for an activity, the only requirement is that the Federal agency involved in permitting the activity avoids the destruction or adverse modification of critical habitat. Infrequently there are some costs to private landowners in such cases as third-party applicants.

The Service believes that restrictions alone are neither an effective nor a desirable means for achieving the conservation of listed species. We prefer to work collaboratively with private landowners, and strongly encourage individuals with listed species on their property to work with us to develop incentive-based measures such as SHAs or HCPs, which have the potential to provide conservation measures that effect positive results for the species and its habitat while providing regulatory relief for landowners. The conservation and recovery of endangered and threatened species, and the ecosystems upon which they depend, is the ultimate objective of the Act, and the Service recognizes the vital importance of voluntary, nonregulatory conservation measures that provide incentives for landowners in achieving that objective.

(23)
Comment:
One commenter argued that, while the Service determined road construction associated with development causes fragmentation of habitat in the south Puget Sound region, the Service previously concluded that road construction can have a positive effect on pocket gopher species, referencing a rule issued for another species of pocket gopher in Wyoming.

Our Response:
The Service referenced the rule cited by the commenter, which states “We conclude the effects of roads on the Wyoming pocket gopher may be both positive and negative. Although we remain concerned about roads, the best available information does not indicate that road construction and use pose a threat to the Wyoming pocket gopher now, or in the foreseeable future.” (75 FR 19600; April 15, 2010). We draw the commenter's attention to the Wyoming counties discussed in the finding and highlight the following: The human population density of Sweetwater and Carbon Counties in 2010 when the determination was made for the Wyoming pocket gopher was 4 and 5 people per square mile, respectively. Thurston County has a population density of 334 people per square mile (47 square miles of which are water and thus uninhabitable by gophers). Clearly, there is a significant difference in the human population between these areas, which extends to a high degree of difference in the density of roads; for this reason, the Service determined that road construction may not have a large effect in the case of the Wyoming pocket gopher but could have a negative effect on the Mazama pocket gopher subspecies in Thurston County. With the population of Thurston County projected to increase by approximately 141,000 people by the year 2040 (Thurston Regional Planning Council 2012, pp. 30, 32), raising the density to greater than 550 people per square mile, the corresponding increase in infrastructure will only further disrupt and fragment the remaining remnants of habitat.

(24)
Comment:
One commenter asserted that the listing determination incorrectly assumes that development in Thurston County poses the same risk to the four Thurston/Pierce subspecies of Mazama pocket gopher as earlier development did in Pierce County for the Tacoma pocket gopher, which is now presumed extinct.

Our Response:
While we do not disagree that the threat of development in Pierce County is likely unequal to the threat of development in Thurston County, the threat analyses conducted for the four Thurston/Pierce subspecies of Mazama pocket gopher took many factors into account when making the determination of threatened species status. The tremendous loss of Mazama pocket gopher habitat to development in Thurston County is indisputable. Combined with fragmentation and isolation of habitat; the subsequent loss of connectivity between populations and, therefore, gene flow, increased predation pressures associated with proximity to development, habitat degradation due to the spread of invasive plants, and successional changes in grasslands attributable to development-associated fire suppression, we made the determination that the four Thurston/Pierce subspecies of Mazama pocket gopher are indeed threatened. This determination stands despite the likely differential in development pressures of historical Pierce and present-day Thurston Counties.

(25)
Comment:
One commenter suggested that increased burrowing activity after soil disturbance and other manmade environmental modifications such as installation of underground utility services or land clearing was evidence of the Mazama pocket gopher's ability to adapt to changing conditions. Several commenters observed that some environmental consultants are recommending against protection for the four Thurston/Pierce subspecies of the Mazama pocket gopher and that they are reporting observations of pocket gophers in clear cuts, on Christmas tree farms, and in areas where soils have been highly disturbed through anthropogenic processes, such as in the Artillery Impact Area (AIA) at Joint Base Lewis-McChord (JBLM).

Our Response:
While it may look as if there are a lot of new mounds in areas where soil disturbance has recently occurred, this may be the activity of as few as one or two pocket gophers that are excavating new tunnel systems, attempting to reconstruct compacted or destroyed burrows, or, if much of the herbaceous vegetation has been removed from the surface of the soil, they may be expanding their tunnel system in order to increase their forage area. The presence of numerous gopher mounds does not necessarily mean that there are a lot of gophers or that the gophers present are thriving and able to persist long term (Olson 2011a, p. 37).

Due to fire suppression, much of the historical prairie landscape has been converted to timber through the succession of the plant community. If the underlying soils were formerly suitable Mazama pocket gopher habitat, removal of timber re-exposes this temporarily inaccessible habitat and any nearby population could potentially disperse into or otherwise make use of the opening. Similarly, Christmas tree farms that are situated on suitable or occupied habitat may not exclude Mazama pocket gophers, especially if the associated agricultural practices do not include heavy herbicide use or extensive mechanical soil manipulation. It is true that the AIA of JBLM appears to have been continuously occupied, at least patchily, for a very long time. The Service believes the ability of Mazama pocket gophers to use this habitat is due in part to, not in spite of, the year-round bombardment of the central impact area: Ignition of dry standing vegetation attributable to bombardment leads to low-intensity burns across the 91st Division Prairie where the AIA is located. The effect of these burns, aside from mimicking the historical burning regime, is that they prevent woody encroachment and encourage a vegetative community similar to the kind the Mazama pocket gopher evolved with; in essence, their ideal forage community. Due to the sporadic nature of artillery training, it is not unexpected that individual Mazama pocket gophers would disperse and create tunnels into

the high-intensity impact area at the center of the prairie, especially if the outer edges of the prairie have a high density of Mazama pocket gophers.

(26)
Comment:
One commenter suggested that a translocation study previously conducted on Mazama pocket gophers supports the relocation of pocket gophers from urban areas to unoccupied prairies as a viable management tool to sustain the species over the long term.

Our Response:
The study referenced was discussed at length in the proposed rule (77 FR 73770; December 11, 2012). It was the first of its kind and initially resulted in extremely high mortality rates for the translocated gophers. While deaths attributable to translocation declined as techniques improved, long-term monitoring will be required before it is possible to determine whether or not a “new” population has been established without continual addition of new individuals. Further it is difficult to determine whether or not a site (e.g., Mima Mounds Natural Area Preserve or Mima Prairie Glacial Heritage Preserve) provides appropriate habitat if there is no historical record of occupancy. Some of these sites superficially appear to have characteristics of suitable habitat, but are not currently documented as occupied and have no historical record of occupancy. Overall, we do not believe translocation of gophers from one area to another is a sustainable approach to conserving the species in the long term. We are collaborating with land owners, local governments, and the business community to develop a range-wide habitat conservation strategy that may include translocation as an appropriate tool in certain circumstances.

(27)
Comment:
One commenter suggested that there is not enough information about pet predation on Mazama pocket gophers to conclude that the threat is significant and cited a comment submitted by the WDFW stating the same.

Our Response:
While the Service is unaware of any pet predation studies that apply specifically to the Mazama pocket gopher, we have received numerous firsthand reports of pet predation on pocket gophers in general and Mazama pocket gophers specifically from both WDFW and Service biologists. Supplementing these observations with citizen reports received from non-biologists and incidents documented by video, we have concluded that pet predation is likely a common occurrence and we consider it a threat to the four Thurston/Pierce subspecies of Mazama pocket gopher in the south Puget Sound region. In most cases, biologists do not consider predation on individual animals as a threat to their respective populations as a whole; when considering endangered or threatened species, though, populations may be depressed to the point that the loss of individual animals becomes disproportionally important. Mazama pocket gophers are somewhat solitary in nature, and due to the known loss of occupied habitat through conversion to incompatible uses (e.g., development, mineral extraction, etc.) and the increasingly fragmented habitat that remains, we contend that loss of individual animals may have greater than normal impacts to the overall health of their populations. In WDFW's second comment letter they agreed that predation was appropriate to include as a threat, so it could be further examined and compared to the other well-documented threats to determine actions that may be needed during the recovery process for the four Thurston/Pierce subspecies Mazama pocket gophers.

(28)
Comment:
Many commenters believe that Washington State's Growth Management Act (GMA) provides enough regulatory certainty to protect Mazama pocket gophers in Washington into the foreseeable future, therefore, precluding the need to list them as a threatened species under the Act.

Our Response:
We disagree. Washington State's GMA was crafted to provide land use guidance that would result in conservation of State resources and wise land use practices. The GMA outlines 13 goals to guide the development of regulations at the county and municipality levels, but it does not mandate the establishment of performance measures or the requirement of monitoring, thus there is no standardized metric or means by which to quantify the success or failure of the resulting regulation. The Service recognizes that the GMA has produced some tangible conservation benefits, but variability in the formulation, implementation, and enforcement of the ensuing regulations has allowed for divergent planning practices across the State as well as a broad range of results at individual sites where required mitigation has taken place. Further, current implementation of the GMA fails to sufficiently curb the continued fragmentation and loss of Mazama pocket gopher populations and habitat. (Also see response to Comment 17). For these reasons and others, as detailed in our Summary of Factors Affecting the Species, we have determined that existing regulatory mechanisms, including the GMA, are inadequate to ensure the conservation of the Mazama pocket gopher.

(29)
Comment:
One commenter concluded that the final rule determining threatened status for the four Thurston/Pierce subspecies of Mazama pocket gopher would reverse the benefits of Washington State's GMA by reducing human population density in the Urban Growth Areas (UGAs) and increasing sprawl in rural areas.

Our Response:
The Service is actively engaged with county and municipal governments (e.g., Thurston County, City of Tumwater, and Port of Olympia) to support the results of Washington's GMA and land-use planning under the Act.

(30)
Comment:
One commenter posited that the development threats and pressures that may have led to the extirpation of the Tacoma pocket gopher took place prior to the passage of Washington State's GMA and that, due to the differences between past and current regulations, conclusions about current and future threats to the Mazama pocket gopher in Washington should not be considered to be equivalent. In other words, the commenter felt the more recent State regulations are sufficient to prevent the four Thurston/Pierce subspecies from going the way of the Tacoma pocket gopher.

Our Response:
We generally agree that the GMA has helped to reduce threats to the four Thurston/Pierce subspecies, although loss of Mazama pocket gopher habitat to development pressures still remains a threat. Additionally, although the GMA and associated critical areas protections have certainly provided greater protection to priority habitats and species than existed prior to their passage, it does not necessarily follow that they are sufficient to conserve the four Thurston/Pierce subspecies of the Mazama pocket gopher given the subspecies' current status and fragmented distribution. Overall the effectiveness or timeliness of regulations to conserve a species is partially dependent upon when the actual conservation concern for the species of interest was recognized or identified as a need. Regulations implemented after significant habitat has been lost will not have the same conservation impact as those implemented when significant portions of habitat still remain intact.

(31)
Comment:
One commenter asserted that the Service dismisses the WDFW Priority Habitat and Species (PHS) program as a legal nullity for listing under the Act. Another commenter said that the WDFW PHS recommendations requires the use of standardized performance measures in

the development of Habitat Management Plans (HMPs) and that the recommendation is enough of a safeguard against variability in the implementation of the HMPs to preclude the listing of the four Thurston/Pierce subspecies of the Mazama pocket gopher.

Our Response:
The Service does not dismiss the contribution that the PHS program provides in the form of consultation and guidance on land use issues affecting priority habitats and species. However, we note the limitations of their PHS Management Recommendations, and reflect WDFW's own characterization of the PHS: “These recommendations are not regulatory, but are based on best available science for avoiding, minimizing, and mitigating impacts to gophers and their habitat, which is primarily located in South Puget Sound. WDFW recommends the following mitigation sequence for reviewing and conditioning proposed development projects with potential impacts to Mazama pocket gophers” (WDFW 2011, p. 1). Because these are recommendations and are explicitly not regulatory in nature, we do not weight them equally to existing law when evaluating the adequacy of existing regulatory mechanisms.

While the PHS allows for WDFW recommendations to become mandatory performance measures in HMPs when required and adopted by local governments, this has not occurred consistently. Performance measures must be capable of assessing the quality and efficacy of the executed plan. In order to do so, performance measures must mandate objective and measurable metrics that are used to delineate performance thresholds for success and are standardized across all plans.

Further, the PHS specifies that the recommendations for HMP development are not regulatory in nature, leaving individual planning authorities to determine implementation practices, including management and enforcement. While the PHS recommendations do specify that HMPs should be submitted to WDFW for review, the review process only occurs as WDFW resources allow, which leads to inconsistent results. Further, should WDFW staff make specific recommendations, these recommendations may or may not be implemented by the County, especially where a land use variance has been approved. The Service does not agree that these recommendations provide enough regulatory certainty to ameliorate threats to the Mazama pocket gopher to the extent that listing would not be warranted.

(32)
Comment:
Several commenters either asked how effective mitigations resulting from the current GMA critical areas regulations have been or stated that the mitigations had been successful or unsuccessful. Some commenters averred that successful mitigation should preclude the listing of the four Thurston/Pierce subspecies of the Mazama pocket gopher while others highlighted the weaknesses in the implementation of the recommendations and regulations.

Our Response:
Due to the lack of performance measures, there is no standard metric of success or failure of the GMA critical areas regulations. Furthermore, due to lack of monitoring, there is not a comprehensive list of sites where mitigation measures have been implemented and where Mazama pocket gopher populations are being tracked. Of the sites where Habitat Management Plans (HMPs) have been developed as required under the critical areas regulations and shared with the Service, many of the plans do not appear to have adequately provided for the habitat needs of the Mazama pocket gopher, in some cases overlaying water retention ponds with habitat set-asides. Due to the lack of consistency between regulations, variability in implementation of approved HMPs, the lack of requirement of performance measures or monitoring, and a lack of enforcement, the Service does not find the existing regulations to be effective at protecting and sustaining Mazama pocket gopher populations or habitat at a level consistent with the persistence of the species into the foreseeable future.

(33)
Comment:
Several commenters concluded that the Service found the existing State and local regulatory scheme adequate to protect gophers in areas outside of Thurston County, despite the fact that those jurisdictions have even lesser critical area protections.

Our Response:
This statement is not correct. The Service actually concluded that although the existing State and local regulatory schemes provided some conservation measures, they are inadequate to reduce the threats within both Thurston and Pierce Counties (See threats discussion in our proposed rule; 77 FR 73770, pp. 73782-73786). In other counties where the Olympic, Shelton, or Cathlamet subspecies of Mazama pocket gophers are located, we currently have no evidence to suggest existing regulatory mechanisms are inadequate to such a degree that they pose a threat given the current status of these subspecies and their habitats.

(34)
Comment:
A comment submitted by a representative of the petroleum industry asserted that the impacts of impending climate change are not foreseeable.

Our Response:
The vast majority of the body of literature contributed by adherents to the scientific method projects an increasing trend toward higher-than-average temperatures worldwide accompanied by an increased frequency in stochastic weather events, many of which present real and foreseeable threats. The Service does not consider climate change as a threat for the four Thurston/Pierce subspecies of the Mazama pocket gopher because the threat is not imminent given the organism's fossorial lifestyle and propensity to use exceedingly well-drained soils, which may provide a buffer from the most predictable aspects of a changing climate. This should not be misconstrued as an indicator that the Service believes that climate change is not a threat in the long term.

(35)
Comment:
One commenter stated that, despite following State recommendations for infrastructure development that complies with the Clean Water Act while simultaneously accommodating projected population growth in Thurston County, the listing determination and designation of critical habitat for the four Thurston/Pierce subspecies of the Mazama pocket gopher communicates to the public that participation in such processes is a useless exercise.

Our Response:
The Service encourages all parties involved in the development of infrastructure to comply with all Federal and State recommendations and laws. We additionally wish to draw attention to the annually updated list of species that are candidates for listing under the Act, which has included the Mazama pocket gopher since 2001. The Service works closely with Federal, State, county, and municipal planners to publicize the status of these candidate species so that the public, and specifically developers, will be able to make informed decisions when planning for future development at all scales.

(36)
Comment:
Several commenters suggested that, faced with the prospect of Federal regulations attributable to the listing of the Mazama pocket gopher, land owners will be more inclined to maintain their land in a way that would discourage pocket gopher presence on their property.

Our Response:
Although some landowners may choose to maintain their land in such a way, we do not anticipate this to universally be the case. Many Thurston and Pierce County landowners have communicated a

desire to manage their lands in such a way that enhances prairie habitat. The Service recognizes these landowners and encourages positive stewardship that preserves biodiversity and local ecosystems. In this final rule, we have expanded the protections provided to residential and agricultural landowners under the 4(d) special rule for activities that support the maintenance of the open, early-seral conditions the Mazama pocket gopher prefers. We also encourage property owners who believe they have Mazama pocket gophers on their property to investigate the potential for a conservation agreement with the Service, some of which allow increased flexibility in land use in exchange for the maintenance of suitable habitat. For more information, please visit:
http://fws.gov/endangered/
and see the “For Landowners” tab.

(37)
Comment:
One commenter urged the Service to take into consideration lands that have been recently protected as conservation areas before publishing a final rule.

Our Response:
We have carefully considered the contribution of all protected lands to the conservation and recovery of the four Thurston/Pierce subspecies of the Mazama pocket gopher before making a final listing decision for each subspecies. We concluded there are currently an insufficient number and distribution of permanently protected areas for the four Thurston/Pierce subspecies of the Mazama pocket gopher to preclude the need to list them under the Act.

(38)
Comment:
Several commenters wanting the Service to make the proposed 4(d) special rule more inclusive provided anecdotal accounts of Mazama pocket gophers persisting in landscapes where certain agricultural practices have been taking place for many years (e.g., ranching, raising of nursery trees, row cropping, etc.), but failed to provide the Service with any means by which to verify their statements.

Our Response:
The Service is aware of some sites where Mazama pocket gophers appear to persist concordantly with certain agricultural practices. We have limited information on how different kinds of agricultural practices affect individual Mazama pocket gophers or their populations. Some practices such as subsoil or moldboard ploughing may conceivably have a greater impact on Mazama pocket gophers in the path of the plough than would most grazing and ranching practices. Similarly, shallow tillage may have a very different effect on animals present than deep tillage. Without being able to examine the short- and long-term effects of these practices, it is difficult to know if they are detrimental to Mazama pocket gopher populations where tilling and Mazama pocket gophers may co-occur.

During the 6-month extension for making our final determination, the Service worked collaboratively with the Washington State Department of Agriculture (WSDA) to address uncertainties surrounding the accuracy or sufficiency of the data we used to assess the threat of various agricultural and ranching activities to the Mazama pocket gopher. As part of this effort, WSDA conducted an assessment with cooperating agricultural landowners to evaluate the co-occurrence of the Mazama pocket gopher with certain representative agricultural practices.

The results of the assessment suggest that the Mazama pocket gopher is able to persist in at least some areas where these practices occur. While some of the practices recorded in the assessment may kill individual pocket gophers or negatively impact specific pocket gopher populations, we have expanded the list of permitted activities under our 4(d) special rule to include a broader range of agricultural practices, or address the specific timing of certain practices. We note that some agricultural practices are likely detrimental to the Mazama pocket gopher, but may be perceived as relatively harmless due to the continued presence of gophers on agricultural sites. Among all agricultural activities, deep tillage appears to have the highest likelihood of inadvertently killing the greatest number of individual gophers. The potential scope of impact this activity may cause is limited by virtue of its application to only a subset of agricultural lands and its intermittent use (recommended at a frequency of no more than once every 10 years, by NRCS). Continued presence of gophers on any tilled site may be the result of reoccupancy by remnant individuals from undisturbed field edges, and are not necessarily representative of established and enduring populations within these sites.

The value of maintaining actively working agricultural lands as open and undeveloped areas provides a substantial conservation benefit to the four Thurston/Pierce subspecies of the Mazama pocket gopher. Furthermore, we now have some additional information available to us regarding the compatibility of certain practices with Mazama pocket gopher conservation, as the result of the 6-month extension on this final listing rule and an assessment conducted during that time by WSDA. As a result, we have exempted some additional agricultural practices under the 4(d) special rule (See Special Rule, below.)

(39)
Comment:
Many commenters provided suggestions for revising the 4(d) special rule.

Our Response:
The 4(d) special rule is a provision of the Act that allows for some “take” of a protected species when the overall outcome of the allowed actions are “necessary and advisable to provide for the conservation of the species.” The special rule is not intended to cover activities that do not provide some clear conservation benefit to the species. Many parties requested coverage for their actions under the 4(d) special rule without identifying the conservation benefit those actions would provide for the Mazama pocket gopher. The Service carefully considered all requests and amended the rule where appropriate, but was unable to cover many of the proposed actions. See the section entitled “Special Rule” for details on the revised 4(d) special rule.

Summary of Changes From the Proposed Rule

In making our final determination, we fully considered comments from the public and the peer reviewers on our proposed rule to list the four Thurston/Pierce subspecies of the Mazama pocket gopher as threatened species, and to promulgate a 4(d) special rule for the conservation of these subspecies. This final rule incorporates changes to our proposed listing and 4(d) special rule based on the comments and new information that we received, as summarized above. Changes from the proposed rule that we have incorporated here are as follows:

• We have expanded our discussion of occupied habitat and peripheral (or “stepping stone”) populations in the Habitat and Life History section of this document, as well as our discussion of minimum habitat patch size.

• We received additional distribution data for the Mazama pocket gopher in western Washington, which we have incorporated here. However, this information did not alter the conclusion of our analysis.

• We included a more thorough discussion of the use of soil types and soil type complexes by the four Thurston/Pierce subspecies of the Mazama pocket gopher, which can also be found under the Habitat and Life History section.

• We made some technical corrections and reevaluated the threats to all four subspecies of the Thurston/Pierce subspecies of the Mazama pocket gopher based on comments received

from our State partners, as well as other comments received. Although our analysis of these potential threats is different from that in our proposed rule, none of the information changed our determination that listing each of the four subspecies of the Mazama pocket gopher as threatened species is warranted.

• We have revised the 4(d) special rule based on Federal and State agency comments and public comments. The 4(d) special rule included in our final determination has been broadened from the proposed special rule and has increased the scope of activities and allowable timing of those activities occurring on airport and agricultural and ranching lands; increased the scope of activities occurring on single-family residential properties; more broadly allowed the control of invasive plants and noxious weeds; and included the addition of routine vegetation management activities and fencing along roadside rights-of-way. We have found that such measures are necessary and advisable for the conservation of the species, and, as such, are appropriate for inclusion in our 4(d) special rule. As with all other activities covered by the 4(d) special rule, although exempted from the prohibitions of section 9 of the Act, consultation under section 7 of the Act is still required for those activities that may affect the listed species or their critical habitat in cases where there is a Federal nexus.

Background

Below, in this section of the rule, we discuss only those topics directly relevant to the listing of the Olympia, Roy Prairie, Tenino, and Yelm subspecies of the Mazama pocket gopher found in Thurston and Pierce Counties of Washington State.

Species Information

Although the species
Thomomys mazama,
or the Mazama pocket gopher, includes numerous subspecies that are found in the States of Washington, Oregon, and California (as described below in Taxonomy), only the four Thurston/Pierce subspecies of the Mazama pocket gopher are the subject of this rulemaking. In this document, when we use the general term “Mazama pocket gopher,” we are referring collectively to only those subspecies of
Thomomys mazama
that occur in the State of Washington; as used here, “Mazama pocket gopher” is not intended to include any subspecies of
T. mazama
that occur in the States of Oregon or California.

Adult Mazama pocket gophers are reddish brown to black above, and the underparts are lead-colored with buff-colored tips. The lips, nose, and patches behind the ears are black; the wrists are white. Adults range from 7 to 9 inches (in) (189 to 220 millimeters (mm)) in total length, with tails that range from 2 to 3 in (45 to 85 mm) (Verts and Carraway 2000, p. 2). In Washington, Mazama pocket gophers are found west of the Cascade Mountain Range in the Olympic Mountains and in the Puget Sound trough, with an additional single locality known from Wahkiakum County (Verts and Carraway 2000, p. 3). Their populations are concentrated in well-drained friable soils often associated with glacial outwash. Mazama pocket gophers reach reproductive age in the spring of the year after their birth and produce litters between spring and early summer. Litter size ranges from one to nine (Wight 1918, p. 14), with an average of five (Scheffer 1938, p. 222).

Taxonomy

The Mazama pocket gopher complex consists of 15 subspecies, 8 of which occur only in Washington, 5 of which occur only in Oregon, 1 that occurs only in California, and 1 subspecies with a distribution that spans the boundary between Oregon and California (Hall 1981, p. 467). The first pocket gophers collected in western Washington were considered to be subspecies of the northern pocket gopher (
Thomomys talpoides
) (Goldman 1939), until 1960 when the complex of pocket gophers found in western Washington was determined to be more similar to the western pocket gopher (
T. mazama
) based on characteristics of the baculum (penis bone) (Johnson and Benson 1960, p. 20). Eight western Washington subspecies of the Mazama pocket gopher (
T. mazama,
ssp.
couchi, glacialis, louiei, melanops, pugetensis, tacomensis, tumuli,
and
yelmensis
) have been identified (Hall 1981, p. 467).
Thomomys mazama
is recognized as a valid species by the Integrated Taxonomic Information System (ITIS), as are each of the subspecies (ITIS 2014).

Although there have been some suggestions that potential changes to the classification of some of these subspecies may be considered, as discussed below, we have no information to suggest that any of the presently recognized subspecies are the subject of serious dispute. We consulted with Alfred Gardner, Curator of North American mammals, Smithsonian Institution, National Museum of Natural History, who identified the Mammalian Species Account 641 of the American Society of Mammalogists, authored by Verts and Carraway (2000), as the definitive text for this taxon (Gardner 2012, pers. comm.). Thus we follow the subspecies designations of Verts and Carraway (2000) in this finding, as this text represents the currently accepted taxonomy for the species
Thomomys mazama.

While past descriptions of Mazama pocket gophers have focused on morphological differences in characteristics such as pelage color, skull features, and body size (Bailey 1915; Taylor 1919; Goldman 1939; Dalquest and Scheffer 1942; Dalquest and Scheffer 1944a, b; Gardner 1950; Hall 1981, pp. 465-466), recent genetic evaluations have been conducted on the Mazama pocket gopher complex using mitochondrial deoxyribonucleic acid (mtDNA) sequencing of the cytochrome b gene (Welch 2008). From these and subsequent data, Welch and Kenagy (2008, pp. 6-7) determined that the Mazama pocket gopher complex in Washington is geographically structured into three haplotype clades (genetic groups) representing the following three localities: (1) Olympic Peninsula (Clade A, which includes the Olympic pocket gopher); (2) Mason County (Clade B, which includes the Shelton pocket gopher), and (3) Thurston and Pierce Counties (Clade C, which includes the Roy Prairie, Olympia, and Yelm pocket gophers).

Specimens from the subspecies
Thomomys mazama louiei
(Wahkiakum County) were unobtainable and as such were omitted from Welch and Kenagy's (2008, pp. 1-3) analysis, so what clade the Cathlamet pocket gopher belongs to or if it occupies its own clade is unknown. In addition, no specimens from either the subspecies
T. m. tumuli
(the Tenino pocket gopher) or the presumed extinct subspecies
T. m. tacomensis
(the Tacoma pocket gopher) were readily available and were also not included in the analysis. None of the haplotypes in the analyzed specimens were shared between the three clades, which supports the differentiation of the clades. The mtDNA analysis was not able to distinguish between subspecies in Clade C; more genetic work needs to be done to determine how closely related these subspecies are. Verts and Carraway (2000, p. 1) and the ITIS (2014) recognize
T. m. pugetensis, glacialis, tumuli,
and
yelmensis
(the Olympia, Roy Prairie, Tenino, and Yelm pocket gophers, respectively) as separate subspecies based on differences in morphological characteristics (for example, pelage coloration; skull shape, size, and weight; shape and form of zygomatic arch; jugal bone; foot and tail length) and distribution. For the reasons

described above, we accept this classification of the Olympia, Roy Prairie, Tenino, and Yelm pocket gophers as separate subspecies of the Mazama pocket gopher.

Habitat and Life History

The four Thurston/Pierce subspecies of the Mazama pocket gopher are associated with glacial outwash prairies in western Washington, an ecosystem of conservation concern (Hartway and Steinberg 1997, p. 1) Steinberg and Heller (1997, p. 46) found that Mazama pocket gophers are even more restricted in distribution than are prairies, as there are some remnant high-quality prairies seemingly within the species' range that lack pocket gophers (e.g., Mima Mounds Natural Area Preserve (NAP), and 13th Division Prairie on JBLM). Pocket gopher distribution is affected by the rock content of soils (gophers avoid the rockiest soils), drainage, forage availability, and climate (Case and Jasch 1994, p. B-21; Steinberg and Heller 1997, p. 45; Hafner
et al.
1998, p. 279; Reichman 2007, pp. 273-274; WDFW 2009; also see Stinson 2005, p. 31), thus further restricting the total area of a prairie that may be occupied by gophers. Prairie and meadow habitats used by pocket gophers have a naturally patchy distribution. In their prairie habitats, there is an even patchier distribution of soil rockiness, which may further restrict the total area that pocket gophers can utilize (Steinberg and Heller 1997, p. 45; WDFW 2009). We assume that meadow soils have a similarly patchy distribution of rockiness, though the soil surveys to support this are, at this time, incomplete.

In Washington, Mazama pocket gophers currently occupy the following soil series and soil series complexes: Alderwood, Cagey, Carstairs, Everett, Everett-Spanaway complex, Everett-Spanaway-Spana complex, Godfrey, Grove, Indianola, Kapowsin, McKenna, Murnen, Nisqually, Norma, Shelton, Spana, Spana-Spanaway-Nisqually complex, Spanaway, Spanaway-Nisqually complex, and Yelm. No soil survey information is currently available for the Olympic National Park, so soils series occupied by gophers there are unknown. These soil series and soil series complex names were derived from a GIS overlay of gopher locations with USDA NRCS GIS soil survey data layer (accessed June 20, 2008 for Thurston County; received from JBLM May 30, 2013 for Pierce County). These soil type names are very broad-scale soil series names, and don't include the more specific soil characteristics that come with a full soil map unit name, such as “Spanaway gravelly sandy loam, 0 to 3 percent slopes.”

We are purposely not using specific map unit names because we know that there are imperfections in soil mapping. Mapped soil survey information may be imperfect for a variety of reasons. First, maps are based on the technology, standards, and tools that were available at the time soil surveys were conducted, sometimes up to 50 years ago. We recognize that soil survey boundaries may be adjusted in the future, and that soil series names may be added or removed on the NRCS's soil survey maps database. As a result, the overlap of gopher locations with soil series names may be different in the future. The soils information presented here is based on best scientific data available at the time of listing.

We also recognize that some of these soil series or soil series complexes are not typically either deep or well-drained. For a variety of reasons, a specific mapped soil type may or may not have all of the characteristics of that soil type as described by NRCS, and the actual soil that occurs on the ground may have characteristics that make it inhabitable by Mazama pocket gophers. These reasons may include map boundary or transcription errors, map projection errors or differences, map identification or typing errors, soil or hydrological manipulations that have occurred since mapping took place, small-scale inclusions in the mapped soil type that are different from the mapped soil and which may be used by Mazama pocket gophers, etc. Nevertheless, based on best available data, these are the areas where Mazama pocket gopher locations and mapped soils have been found to overlap when mapped in GIS. All of these soils could potentially be suitable for any of the four Thurston/Pierce subspecies of the Mazama pocket gopher. In addition, the four Thurston/Pierce subspecies of the Mazama pocket gopher may be able to forage or burrow in soil series not on the above list. For these reasons, our list of soils may be incomplete or appear to be overly inclusive. Although some soils are sandier, more gravelly, or may have more or less silt than described, most all soils used by Mazama pocket gophers are friable (easily pulverized or crumbled), loamy, and deep, and generally have slopes less than 15 percent.

In 2011, there were reports of Mazama pocket gophers (subspecies unknown) occurring on new types of soils and on managed forest lands in Capitol State Forest (owned by Washington Department of Natural Resources (WDNR)) and Vail Forest (owned by Weyerhaeuser) in Thurston County. These were subsequently determined not to be Mazama pocket gophers but instead moles (
Scapanus
spp.), based on followup surveying and/or trapping conducted in these areas by Washington Department of Fish and Wildlife (WDFW) during the 2012 gopher survey season (Thompson 2012b, pers. comm.). Please see the discussion in Historical and Current Range and Distribution for more information about the current state of knowledge on this matter for the Mazama pocket gopher.

Mazama pocket gophers are morphologically similar to other species of pocket gophers, all of which exploit a subterranean existence. They are stocky and tubular in shape, with short necks, powerful limbs, long claws, and tiny ears and eyes. Their short, nearly hairless tails are highly sensitive and probably assist in navigation in tunnels. Burrows consist of a series of main runways, off which lateral tunnels lead to the surface of the ground (Wight 1918, p. 7). Pocket gophers dig their burrows using their sharp teeth and claws and then push the soil out through the lateral tunnels (Wight 1918, p. 8; Case and Jasch 1994, p. B-20). Nests containing dried vegetation are generally located near the center of each pocket gopher's home tunnel system (Wight 1918, p. 10). Food caches and store piles are usually placed near the nest, and excrement is piled into blind tunnels or loop tunnels, and then covered with dirt, leaving the nest and main runways clean (Wight 1918, p. 11).

The “pockets” of pocket gophers are external, fur-lined cheek pouches on either side of the mouth that are used to transport nesting material and carry plant cuttings to storage compartments. As with all rodents and lagomorphs (rabbits and hares), their incisors grow continuously (Case and Jasch 1994, p. B-20), though the rate of growth of pocket gopher incisors is higher than most rodents, perhaps to compensate for increased wear resulting from tooth-digging. Pocket gophers also have ever-growing cheek teeth (aradicular hypsodont teeth), presumably an adaptation to compensate for the high rate of wear due to an abrasive diet. Pocket gophers don't hibernate in winter; they remain active throughout the year (Case and Jasch 1994, p. B-20). Many different vertebrates and invertebrates take refuge in gopher burrows, especially during inclement weather, including beetles, amphibians (such as toads and frogs), lizards, snakes, ground squirrels, and smaller rodents (Blume and Aga 1979, p. 131; Case and Jasch 1994, p. B-21; also see Stinson 2005, pp. 29-30).

A variety of natural predators eat pocket gophers, including weasels, snakes, badgers, foxes, skunks, bobcats, coyotes, great horned owls, barn owls, and several hawks (Hisaw and Gloyd 1926, entire; Fichter
et al.
1955, p. 13; Huntly and Inouye 1988, p. 792; Case and Jasch 1994, p. B-21; Stinson 2005, pp. 29-30).

In addition to natural predators, predation by feral and domestic dogs (
Canis lupus familiaris
) and cats (
Felis catus
) is an increasing problem for the four Thurston/Pierce subspecies of the Mazama pocket gopher. Many local populations of the four Thurston/Pierce subspecies of the Mazama pocket gopher are presumed to be small, based on the extent of mounding activity and the solitary and territorial nature of Mazama pocket gophers. Due to their solitary and territorial nature, many sites occupied by one of the four Thurston/Pierce subspecies of the Mazama pocket gopher may contain a small number of individuals and occur in a matrix of residential and agricultural development. With feral or uncontrolled domestic animals in the vicinity, Mazama pocket gophers are exposed to increased levels of predation in these semi-urban and rural environments. In addition, some local populations of the Mazama pocket gopher occur in areas where people recreate with their dogs, bringing these potential predators into environments that may otherwise be relatively free of them, such as wildlife areas or expanses of prairie controlled by DOD, consequently increasing the risks to the pocket gopher.

Pocket gophers are generalist herbivores and their diet includes a wide variety of plant material, including leafy vegetation, succulent roots, shoots, and tubers. In natural settings pocket gophers play a key ecological role by aerating soils, enriching soils with nutrients, activating the seed bank, and stimulating plant growth, though they can be considered pests in agricultural systems. In prairie and meadow ecosystems, pocket gopher activity is important in maintaining species richness and diversity.

The home range of a Mazama pocket gopher is composed of suitable breeding and foraging habitat. Home range size varies based on factors such as soil type, climate, and density and type of vegetative cover (Cox and Hunt 1992, p. 133; Case and Jasch 1994, p. B-21; Hafner
et al.
1998, p. 279). Little research has been conducted regarding home range size for individual Mazama pocket gophers. Witmer
et al.
(1996, p. 96) reported an average home range size of about 1,076 square feet (ft
2
) (100 square meters (m
2
)) for Mazama pocket gophers in one location in Thurston County, Washington. Gopher density varies greatly due to local climate, soil suitability, and vegetation types (Case and Jasch 1994, p. B-21; Howard and Childs 1959, pp. 329-336), and densities are likely to be higher when habitat quality is better. Therefore, this one report on the Mazama pocket gopher (Witmer
et al.
1996) is unlikely to represent the average density across all soil types, vegetation types, and other unique site characteristics across the ranges of the four Thurston/Pierce subspecies of the Mazama pocket gopher. Research on other species of
Thomomys
pocket gophers in other states showed a wide range of home range sizes from approximately 80 to 14,370 ft
2
(7.4 to 1,335 m
2
). Some of these are estimates based on density of gophers trapped per acre, and some are based on measurements of individual gopher territory sizes.

In the absence of studies demonstrating the minimum possible patch size for persistence of the Mazama pocket gopher, we used 50 ac (20 ha) as the smallest area necessary for recovery of Mazama pocket gopher populations, which was the agreed upon estimate of an expert panel (Converse
et al.
2010, pp. 14-15) assembled to assist with the construction of a prairie habitat modeling exercise. We acknowledge the uncertainty with this estimate, but there are currently no studies regarding minimum patch size available for the Mazama pocket gopher, nor are there any obvious means by which a better answer can be obtained. Thus, the best available scientific data in this case is the opinion of an informed expert panel.

Foraging primarily takes place below the surface of the soil, where pocket gophers snip off roots of plants before occasionally pulling the whole plant below ground to eat or store in caches. If above-ground foraging occurs, it's usually within a few feet of a tunnel opening and forage plants are quickly cut into small pieces, and carried in their fur-lined cheek pouches back to the nest or cache (Wight 1918, p. 12). Any water they need is obtained from their food (Wight 1918, p. 13; Gettinger 1984, pp. 749-750). The probability of Mazama pocket gopher occupancy is much higher in areas with less than 10 percent woody vegetation cover (Olson 2011a, p. 16). It is reasonable to conclude that increasing amounts of woody vegetation will shade out the forbs, bulbs, and grasses that gophers prefer to eat, and high densities of woody plants make travel both below and above the ground difficult for gophers. Encroachment of woody vegetation is cited by WDNR as a threat to habitat occupied by the Mazama pocket gopher in Olympic National Park (the Olympic pocket gopher), causing fragmentation and reducing the possibility that individual Mazama pocket gophers will emigrate or immigrate, (thus reducing gene flow) and eventually lead to complete exclusion (Fleckenstein 2013, p. 3). Mazama pocket gophers are not known to occupy areas where woody vegetation is dense and no suitable forage is available (Marsh and Steel 1992, p. 210), which includes areas invaded by the native Douglas fir tree and the invasive shrub, Scot's broom (
Cytisus scoparius
). The Service considers encroachment by woody vegetation to have the potential to have substantial negative impacts on occupied Mazama pocket gopher habitat and thus their populations.

Pocket gophers have been documented to reach sexual maturity during the spring of the year following their birth, and generally produce one litter per year (Case and Jasch 1994, p. B-20), though timing of sexual maturity has been shown to vary with habitat quality (Patton and Brylski 1987, p. 502; Patton and Smith 1990, p. 76). Gestation lasts approximately 18 days (Schramm 1961, p. 169; Anderson 1978, p. 421). Young are born in the spring to early summer (Wight 1918, p. 13), and are reared by the female. Aside from the breeding season, males and females remain segregated in their own tunnel systems. There are 1-9 pups per litter (averaging 5), born without hair, pockets, or teeth, and they must be kept warm by the mother or “packed” in dried vegetation (Wight 1918, p. 14; Scheffer 1938, p. 222; Case and Jasch 1994, p. B-20). Juvenile pelage starts growing in at just over a week (Anderson 1978, p. 420). The young eat vegetation in the nest within 3 weeks of birth, with eyes and ears opening and pockets developing at about a month (Wight 1918, p. 14; Anderson 1978, p. 420). At 6 weeks they are weaned, fighting with siblings, and nearly ready to disperse (Wight 1918, p. 15; Anderson 1978, p. 420), which usually occurs at about 2 months of age (Stinson 2005, p. 26). They attain their adult weight around 4-5 months of age (Anderson 1978, pp. 419, 421). Most pocket gophers live only a year or two, with few living to 3 or 4 years of age (Hansen 1962, pp. 152-153; Livezey and Verts 1979, p. 39).

Pocket gophers rarely surface completely from their burrow except as juveniles, when they disperse above ground from spring through early fall (Ingles 1952, p. 89; Howard and Childs 1959, p. 312). They are highly asocial

and intolerant of other gophers. Each gopher maintains its own burrow system, and occupancy of a burrow system by multiple individuals occurs only for brief periods during mating seasons and prior to weaning young (Ingles 1952, pp. 88-89; Witmer and Engeman 2007, p. 288; Marsh and Steele 1992, p. 209). The mating system is probably polygynous (a single male mates with multiple females) and most likely based on female choice. The adult sex ratio has been reported as biased toward females in most species of pocket gophers that have been studied, often as much as 4:1 (Howard and Childs 1959, p. 296; Patton and Feder 1981, p. 917), though Witmer
et al.
(1996, p. 95) reported a sex ratio of close to 1:1 in Mazama pocket gophers.

Sex ratio may vary with population density, which is often a measure of forage density and soil suitability for burrowing (Patton and Smith 1990, p. 6). One researcher concluded that a site having a deep soil layer that was much less rocky had a pocket gopher population density five times that of another site having rocky soil (Steinberg 1996, p. 26). A study of the relationship between soil rockiness and pocket gopher distribution revealed a strong negative correlation between the proportion of medium-sized rocks in the soil and presence of pocket gophers in eight of nine prairies sampled (medium sized rocks were considered greater than 0.5 in (12.7 mm) but less than 2 in (50.8 mm) in diameter; Steinberg 1996, p. 32). In observations of pocket gopher distribution on JBLM, pocket gophers did not occur in areas with a high percentage of Scot's broom cover in the vegetation, or where mole populations were particularly dense (Steinberg 1995, p. 26). A more recent and methodical study conducted throughout Thurston and Pierce Counties also found that pocket gopher presence was negatively associated with Scot's broom; however, the researcher found no relationship between pocket gopher presence and mole density (Olson 2011a, pp. 12-13).

Pocket gophers have low vagility, meaning they have a poor dispersal capability (Williams and Baker 1976, p. 303).
Thomomys mazama
pocket gophers are smaller in size than other sympatric (occurring within the same geographic area; overlapping in distribution) or peripatric (immediately adjacent to each other but not significantly overlapping in distribution)
Thomomys
species (Verts and Carraway 2000, p. 1). Both dispersal distances and home range size are therefore likely to be smaller than for other
Thomomys
species. Dispersal distances may vary based on surface or soil conditions and size of the animal. For other, larger,
Thomomys
species, dispersal distances average about 131 ft (40 m) (Barnes 1973, pp. 168-169; Williams and Baker 1976, p. 306; Daly and Patton 1990, pp. 1286, 1288). Initial results from dispersal research being conducted on JBLM indicate that juvenile Mazama pocket gophers in Washington usually make movements from 13.1-32.8 ft (4-10 m), though these may not be dispersal movements. One juvenile made a distinct dispersal movement of 525 ft (160 m) in 1 day (Olson 2012b, p. 5). Suitable dispersal habitat is free of barriers to gopher movement, and may need to contain foraging habitat if an animal is required to make a long-distance dispersal move. Potential barriers include, but are not limited to, forest edges, roads (paved and unpaved), abrupt elevation changes, Scot's broom thickets, (Olson 2012b, p. 3), highly cultivated lawns, inhospitable soil types (Olson 2008, p. 4) or substrates, development and buildings, slopes greater than 35 percent, and open water. Barriers may be permeable, meaning that they may impede movement from place to place without completely blocking it, or they may be impermeable, meaning they cannot be crossed. Permeable barriers, as well as lower quality dispersal habitats, may present an intensified risk of mortality to animals that use them (e.g., open areas where predation risk is increased during passage or a paved area where vehicular mortality is high).

Historical and Current Range and Distribution

The following general description of the distribution of the Olympia, Roy Prairie, Tenino, and Yelm subspecies of the Mazama pocket gopher is based on our current knowledge. Steinberg (1996, p. 9) surveyed all historical and many currently known gopher sites. This included all current and formerly known occupied sites listed by the WDNR as having Carstairs, Nisqually, or Spanaway gravelly or sandy loam soil, and that WDNR determined to have vegetation that was intact prairie or restorable to prairie. WDFW and a suite of consultants have surveyed areas of potential gopher habitat in both counties, usually associated with proposed development (WDFW 2012). WDFW has also surveyed areas in relation to various research studies, as well as conducting distribution surveys across five counties in 2012 (Thompson 2012a and b, entire).

Based on current and historical survey information, in Pierce County, Roy Prairie pocket gophers occur generally south and east of I-5, south of Highway 512, and west of State Highway 7. There are prairie-type areas within this described area that have been surveyed multiple times with no detections of pocket gophers, so this description is likely to be an overestimate of the subspecies' range, and likely includes areas surveyed within the historical range of the Tacoma pocket gopher, which is presumed extinct. We acknowledge that few surveys have been conducted off JBLM lands in this area, and our specific knowledge of the range of this subspecies could change in the future.

In Thurston County, the Olympia, Tenino, and Yelm pocket gophers are known to occur east of Black River and south of Interstate 5 and State Highway 101. There are no historical records of Mazama pocket gophers occurring outside of these areas within Thurston County. Soil series and soil series complexes that are known to support pocket gophers do occur outside of these areas. Multiple surveys conducted west of the Black River have consistently yielded negative results (WDFW 2013a). For that reason, there is some confidence that the Black River is a range-restrictive landscape feature. Fewer surveys have been conducted north of Interstate 5 and State Highway 101 (WDFW 2013a), but those also yielded negative results. It is possible that the Mazama pocket gopher may occur north of these highways in Thurston County, but we presently have no gopher occurrence data to support that potential.

The present outermost boundaries of the ranges of each of the four Thurston/Pierce subspecies of the Mazama pocket gopher are likely approximately the same as they were historically. However, entire prairie areas or portions thereof within those outer perimeters have been lost to development and woody plant encroachment (see Summary of Factors Affecting the Species). Therefore, at present Mazama pocket gophers likely occupy fewer total acres than they did historically, and also occupy fewer total areas (that is, there are fewer populations within the area of their diminished range). These four subspecies are known to still occur in their type locality locations (described below), and the areas immediately around those locations are considered to still be part of each subspecies' range. Beyond these areas, uncertainty remains as to the entire areal extent of each subspecies' range, and where or if populations of subspecies coexist or abut one another; each subspecies' range is presumed to extend beyond their type localities. For this reason, the list of soils given for each subspecies below is

shorter than the list given in our final designation of critical habitat for Mazama pocket gopher, published elsewhere in the
Federal Register
today.

The type locality for the Olympia pocket gopher (
Thomomys mazama pugetensis
) was the prairie on and around the Olympia Airport, known as Bush Prairie (Dalquest and Scheffer 1944b, p. 445). Gophers continue to occupy this area. Soil series and soil series complexes in and around this area that may support Mazama pocket gophers include Alderwood, Cagey, Everett, Indianola, McKenna, Nisqually, Norma, Spana, Spanaway-Nisqually complex, and Yelm.

The Roy Prairie pocket gopher (
Thomomys mazama glacialis
) is found in the vicinity of the Roy Prairie and on JBLM in Pierce County. The subspecies was described as plentiful in 1983 but by 1993 the extent of activity at the type locality was described as a “small population” (Steinberg 1996, p. 24). Due to proximity to the subspecies' type locality, it is likely that gophers occurring on 91st Division Prairie and Marion Prairie in Pierce County contain this subspecies. Soil series and soil series complexes in and around this area that may support Mazama pocket gophers include Alderwood, Everett, Everett-Spanaway complex, Everett-Spanaway-Spana complex, Nisqually, Spana-Spanaway-Nisqually complex, and Spanaway.

Tenino pocket gophers (
Thomomys mazama tumuli
) were originally found in the vicinity of the Rocky Prairie NAP, near Tenino (Dalquest and Scheffer 1942, p. 96), a relatively small-extent prairie area. Gophers still reside there, but WDFW researchers have not seen consistent occupancy of the area by gophers in recent years (Olson 2010,
in litt.
), suggesting that the activity intermittently detected in the NAP may be attributable to individuals dispersing in from a currently unidentified nearby source. Soil series and soil series complexes in this area that may support Mazama pocket gophers include Everett, Nisqually, Norma, Spanaway, and Spanaway-Nisqually complex.

Yelm pocket gophers (
Thomomys mazama yelmensis
) were originally found on prairies in the area of Grand Mound, Vail, and Rochester (Dalquest and Scheffer 1944b, p. 446). Surveys conducted in 1993-1994 found no gophers near the towns of Vail or Rochester (Steinberg 1995, p. 28). More recent surveys have reported gophers near Grand Mound, Littlerock, Rainier, Rochester, and Vail (Krippner 2011, p. 31), though WDFW biologists question the validity of the reports near Littlerock and Vail (WDFW 2013b, enclosure 1, p. 3). Soil series and soil series complexes in and around these areas that may support Mazama pocket gophers include Alderwood, Everett, Godfrey, Kapowsin, McKenna, Nisqually, Norma, Spana, Spanaway, Spanaway-Nisqually complex, and Yelm.

Population Estimates/Status

There are few data on historical or current population sizes of Mazama pocket gopher populations in Washington, although several local populations and one subspecies are believed to be extinct. Knowledge of the past status of the Mazama pocket gopher is limited to distributional information. Recent surveys have focused on determining current distribution, primarily in response to development applications. In addition, in 2012, WDFW initiated a 5-county-wide distribution survey. Because the object of all of these surveys has mainly been to determine presence/absence only, total population numbers for each subspecies are unknown. As discussed under Current and Historical Range and Distribution, the precise boundaries of each subspecies' range are not currently known. Local population estimates have been reported but are based on using apparent gopher mounds to delineate the number of territories, a method that has not been validated (Stinson 2005, pp. 40-41). Olson (2011a, p. 2) evaluated this methodology on pocket gopher populations at the Olympia Airport and Wolf Haven International. Although there was a positive relationship between the number of mounds and number of pocket gophers, the relationship varies spatially, temporally, and demographically (Olson 2011a, pp. 2, 39). Based on the results of Olson's 2011 study we believe past population estimates (Stinson 2005) may have been too high. As there is no generally accepted standard survey protocol to determine population size for pocket gophers, it is not currently possible to obtain an estimate of subspecies population sizes or trends. Overall habitat availability has declined, however, and habitat has a finite ability to support pocket gophers, though the number of gophers any one patch can support may vary due to a variety of factors related to habitat quality and population dynamics. For these reasons, the Service concludes the overall population trend of each of the four Thurston/Pierce subspecies of the Mazama pocket gopher is negative.

Increased survey effort since 2007 resulted in the identification of numerous additional occupied sites located on private lands, especially in Thurston County (WDFW 2013a). Some of these new detections are adjacent to other known occupied sites, such as the population at the Olympia Airport. The full extent of these smaller discontiguous sites is currently unknown, and no research has been done to determine whether or not these aggregations are “stepping stone” sites that may facilitate dispersal into nearby unoccupied suitable habitat or if they are population sinks (sites that do not add to the overall population through recruitment). Others of these additional occupied sites are separate locations, seemingly unassociated (physically) with known populations (Tirhi 2008,
in litt.
). The largest known expanse of areas occupied by any subspecies of the Mazama pocket gopher in Washington occur on JBLM (Roy Prairie and Yelm pocket gophers), and at the Olympia and Shelton airports (Olympia and Shelton pocket gophers, respectively).

A translocated population of Mazama pocket gophers occurs on Wolf Haven International's land near Tenino, Washington. Between 2005 and 2008, over 200 gophers from a variety of areas in Thurston County (some from around Olympia Airport (Olympia pocket gopher,
Thomomys mazama pugetensis
)) and some from near the intersection of Rich Road and Yelm Highway (assumed to be Olympia pocket gophers) were released into the 38-ac (15-ha) mounded prairie site. Based on the best available information, we do not believe the property contained Mazama pocket gophers previously. Today pocket gophers continue to occupy the site (Tirhi 2011,
in litt.
); however, current population estimates are not available. Another site, West Rocky Prairie Wildlife Area, has received a total number of 560 translocated pocket gophers (
T. m. pugetensis
) from the Olympia Airport between 2009 and 2011. Initial translocation efforts in 2009 were only marginally successful; a majority of the pocket gophers died within 3 days due to predation (Olson 2009, unnumbered p. 3). Modified release techniques used in 2010 and 2011 resulted in improved survival rates of gophers translocated to West Rocky Prairie Wildlife Area (Olson 2011c, unnumbered p. 4). It is too soon to know if the population will become self-sustaining in the absence of additional translocations. Here we note that this experimental population was inadvertently placed within what appears to have been the historical range of the Tenino pocket gopher (
T. m. tumuli
).

Summary of Factors Affecting the Species

Section 4 of the Act (16 U.S.C. 1533), and its implementing regulations at 50 CFR part 424, set forth the procedures for adding species to the Federal List of Endangered and Threatened Wildlife and Plants. Under section 4(a)(1) of the Act, we may list a species based on any of the following five 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; and (E) other natural or manmade factors affecting its continued existence. Listing actions may be warranted based on any of the above threat factors, singly or in combination. Each of these factors is discussed below.

In making this finding, information pertaining to each of the subspecies in question in relation to the five factors provided in section 4(a)(1) of the Act is discussed below. In considering what factors might constitute threats, we must look beyond the mere exposure of the species to the factor to determine whether the species responds to the factor in a way that causes actual negative impacts to the species. If there is exposure to a factor, but no response, or only a positive response, that factor is not a threat. If there is exposure and the species responds negatively, the factor may be a threat and we then attempt to determine how significant a threat it is. If the threat is significant, it may drive or contribute to the risk of extinction of the species such that the species warrants listing as an endangered or threatened species as those terms a

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Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/fr%3A2014-07414. Public record. Not legal advice.