Voglio sapere a riguardo di…

53596

Federal Register / Vol. 86, No. 185 / Tuesday, September 28, 2021 / Proposed Rules
essential to the conservation of the Penasco least chipmunk:
1 Areas within the White Mountains:
a Between elevations of 2,5003,597
meters 8,20011,800 feet, b That contain rock outcrops or talus, and c That are subalpine Thurbers fescue meadow/grassland communities found within openings of spruce-fir forest, above tree line in the glacial cirque, containing tall bunchgrasses, including Thurbers fescue, sedges, flowering forbs, and shrubs.
2 Forage, including species of Asteraceae, flowers and fruits of gooseberry Ribes spp, wild strawberry Fragaria spp., pinyon Pinus edulis nuts, Gambel oak Quercus gambelii acorns, and insects.
Special Management Considerations or Protection When designating critical habitat, we assess whether the specific areas within the geographical area occupied by the species at the time of listing contain features that are essential to the conservation of the species and which may require special management considerations or protection. The features essential to the conservation of the Penasco least chipmunk may require special management considerations or protections to reduce the following threats: 1 Forest encroachment due to altered fire regime; 2 recreation, development, land use, and land management; 3 destruction of habitat by nonnative species feral hogs; and 4 disease.
Management activities that could ameliorate these threats include, but are not limited to: Prescribed fire and forest management to maintain the open subalpine meadows with native vegetation; continued closure of the encompassing Forest Service allotment to grazing; disease management; and feral hog management.
In summary, we find that the occupied areas we are proposing to designate as critical habitat contain the physical or biological features that are essential to the conservation of the species and that may require special management considerations or protection. Special management considerations or protection may be required of Federal agencies that may take actions in designated critical habitat in order to eliminate, or to reduce to negligible levels, the threats affecting the physical and biological features of the unit.

VerDate Sep<11>2014

16:08 Sep 27, 2021

Jkt 253001

Criteria Used To Identify Critical Habitat As required by section 4b2 of the Act, we use the best scientific data available to designate critical habitat. In accordance with the Act and our implementing regulations at 50 CFR
424.12b, we review available information pertaining to the habitat requirements of the species and identify specific areas within the geographical area occupied by the species at the time of listing and any specific areas outside the geographical area occupied by the subspecies to be considered for designation as critical habitat.
We are proposing to designate critical habitat in areas within the geographical area that was occupied by the species at the time of listing. We also are proposing to designate specific areas outside the geographical area that was occupied by the species at the time of listing because we have determined that a designation limited to occupied areas would be inadequate to ensure the conservation of the species.
Furthermore, we conclude there is a reasonable certainty that the unoccupied area will contribute to the conservation of the species and contains one or more of those physical or biological features essential to the conservation of the species. We have also determined that the unoccupied area falls within the regulatory definition of habitat at 50 CFR 424.02.
The current distribution of the Penasco least chipmunk is much reduced from its historical range. We anticipate that recovery will require continued protection of the existing population and its habitat, and potentially reintroduction of Penasco least chipmunk into historically occupied areas in the Sacramento Mountains, ensuring there are adequate numbers in both of the two historical locations. This strategy will help to ensure that catastrophic events, such as the effects of fire, cannot simultaneously affect all known populations.
Rangewide recovery considerations, such as maintaining existing genetic diversity and striving for connectivity within portions of the species current range to allow adequate movement to assure genetic diversity, were considered in formulating this proposed critical habitat.
Sources of data for this proposed critical habitat designation include multiple reports and discussions with species experts, including New Mexico Department of Game and Fish see SSA
report. We have also reviewed available information that pertains to the habitat requirements of this species. Sources of
PO 00000

Frm 00030

Fmt 4702

Sfmt 4702

information on habitat requirements include studies conducted at occupied sites and published in peer-reviewed articles and agency reports, and data collected during monitoring efforts.
Areas Occupied at the Time of Listing The proposed critical habitat designation does not include all areas known to have been occupied by the Penasco least chipmunk historically;
instead, it focuses on the currently occupied area within the historical range that retains the necessary physical or biological features that will allow for the maintenance and expansion of the existing population. We are not proposing any critical habitat in the Sacramento Mountains because we conclude that the area no longer has the ability to support the species.
We delineated occupied and unoccupied critical habitat unit boundaries using the following geospatial methodology:
1 First, we compiled all known Penasco least chipmunk observations i.e., captures in the White Mountains from 19312018, mapped their locations, and eliminated duplicate records. This process provided a bounded estimate of the subspecies known range.
2 Using existing U.S. Forest Service vegetation mapping for the Lincoln National Forest, we identified and exported all vegetation classes that coincided with the known observations.
The vegetation classes included 1
mixed grass-forb and 2 Gambel oak, which are consistent with physical habitat descriptions for the subspecies in the White Mountains. Vegetation characterized by meadow/grassland community within openings of sprucefir forest are one of the physical or biological features essential to the conservation of the Penasco least chipmunk.
3 Next, we determined the elevation interval in which the White Mountains population has been observed. We used that interval to further define the extent of the grass-forb and Gambel oak vegetation classes. Although the upper limit of the occupied interval did not extend to the highest points within the critical habitat units, we assumed that the Penasco least chipmunk is capable of occupying these higher elevations as the difference roughly 100 meters or 330 feet is not substantial. Therefore, we extended the interval to include the highest peaks within each unit. This process resulted in a basic model of potential habitat.
4 Finally, we refined the output of step 3 above through aerial photo interpretation in order to correct for the
E:FRFM28SEP1.SGM

28SEP1