Mount Graham Red Squirrel Taxonomy
BISON-M Taxonomy
Species: Mt. Graham Red Squirrel
(Tamiasciurus hudsonicus grahamensis (AZ))
Species Id 050811
Date 20 OCT 9
TAXONOMY:
NAME ................... Squirrel, Red, Mt. Graham
OTHER COMMON NAMES .....
ELEMENT CODE ........... AMAFB08011
BLM CODE ...............
CATEGORY ............... Mammals
PHYLUM, AND SUBPHYLUM ... Chordata, Vertebrata
CLASS, AND SUBCLASS ..... Mammalia, Theria
ORDER, AND SUBORDER ..... Rodentia, Sciurognathi
FAMILY, AND SUBFAMILY ... Sciuridae, Sciurinae
GENUS, AND SUBGENUS ..... Tamiasciurus,
SPECIES ................ hudsonicus
SUBSPECIES ............. grahamensis (AZ)
ACCOUNT ................ Single Ssp, < full species
AUTHORITY ..............
SCIENTIFIC NAME ........ Tamiasciurus hudsonicus grahamensis (AZ)
TAX.ORDER .............. 13245
TAXONOMY REFERENCES - 01
COMMENTS ON TAXONOMY
For information regarding other subspecies of T. hudsonicus, see
accounts 050810 and 050812.
Taxonomy - 1
BISON-M Status
Species: Mt. Graham Red Squirrel
(Tamiasciurus hudsonicus grahamensis (AZ))
Species Id 050811
Date 20 OCT 97
STATUS:
CODED STATUS REFERENCES
Federal: Endangered 01
Federal: Recovery Plan Approved 02
Federal: Critical Hab. Designated (AZ) 03
USFS Sensitive: Region 3 (NM,AZ) 01
State AZ: FORMER STATUS; Endangered 01
State AZ: Species of Special Concern 04
Heritage Global: Very Rare/Critically Imperiled (G01
Heritage AZ: Very Rare in AZ (S1) 01
Heritage Ranking: Taxon Tracked by Heritage Progra01
Heritage Ranking: See comments 01
COMMENTS ON STATUS
1993: In 1993, a Federal Recovery Plan was approved for this
species (AGFD,1995) *02*.
1995: Tamiasciurus hudsonicus grahamensis was listed under
the Natural Heritage Global Rank "G5T1" ("G5" = [species
listed "Demonstrably Secure"; "T1" = [subspecies listed]
"Very Rare") (AGFD, 1995) *01*.
1995: The subspecies, Tamiasciurus hudsonicus grahamensis,
was being "Tracked": data were being actively accumulated
and entered into computerized and manual files by the
Heritage Program (AGFD, 1995) *01*.
ARIZONA
1995: Mount Graham Red Squirrel (Tamiasciurus hudsonicus
grahamensis). Arizona State Endangered. Critical Habitat
proposed for high elevations in the Pinaleno Mountains
(AGFD, 1995) *01*.
1995: This species was granted Designated Critical Habitat
in Arizona (AGFD,1995) *03*.
1995: Tamiasciurus hudsonicus grahamensis was listed under
the Natural Heritage Arizona State Rank "S1"
("S1" = "Very Rare") (AGFD, 1995) *01*.
1996: The Mount Graham red squirrel (T.h.grahamensis) was
listed as an Arizona Species of Special Concern
(AGFD, 1996) *04*
Status - 1
BISON-M Distribution
Species: Mt. Graham Red Squirrel
(Tamiasciurus hudsonicus grahamensis (AZ))
Species Id 050811
Date 20 OCT 97
DISTRIBUTION - State and County:
States - Known to occur:
STATE REFERENCES
AZ: Extant 01
ARIZONA COUNTY DISTRIBUTION DATA REFERENCES
Graham 06
OTHER DISTRIBUTION:
COMMENTS ON DISTRIBUTION
ARIZONA
1996: The Mount Graham red squirrel (T.h.grahamensis) is
restricted primarily to spruce-fir and old growth Douglas-fir
forests at higher elevations of the Pinaleno (Graham)
Mountains (AGFD, 1996)*04*.
Distribution - 1
BISON-M Habitat Associations
Species: Mt. Graham Red Squirrel
(Tamiasciurus hudsonicus grahamensis (AZ))
Species Id 050811
Date 20 OCT 97
HABITAT:
COMMENTS ON HABITAT ASSOCIATIONS
ARIZONA
The Mount Graham red squirrel (T.h.grahamensis) is restricted
primarily to spruce-fir and old growth Douglas-fir forests
at higher elevations of the Pinaleno (Graham) Mountains
(AGFD, 1996)*04*.
Habitat - 1
BISON-M Food Habits
Species: Mt. Graham Red Squirrel
(Tamiasciurus hudsonicus grahamensis (AZ))
Species Id 050811
Date 20 OCT 97
FOOD HABITS:
Food Habits - 1
BISON-M - Environment
Species: Mt. Graham Red Squirrel
(Tamiasciurus hudsonicus grahamensis (AZ))
Species Id 050811
Date 20 OCT 97
ENVIRONMENT:
G = General A = Adult
LIM = Limiting RA = Resting Adult
J = Juvenile FA = Feeding Adult
RJ = Resting Juvenile BA = Breeding Adult
FJ = Feeding Juvenile P = Pupae
L = Larvae E = Egg
RL = Resting Larvae FL = Feeding Larvae
LIFESTAGE ENVIRONMENTAL ASSOCIATIONS
BA Terrestrial Features: Leaf nests
BA Snag: Specified in Comments
REFERENCES FOR BREEDING ADULT ENVIRONMENTAL ASSOC. - 07
COMMENTS ON BREEDING ADULT ENVIRONMENTAL ASSOC.
Sixty six percent (n=40) of Mount Graham red squirrel nests
examined were located in cavities within snags, 26% (n=16)
were bolus nests, and 7% (n=4) were ground nests
(Point, et al., 1997) *07*.
Environmental Associations - 1
BISON-M - Life History
Species: Mt. Graham Red Squirrel
(Tamiasciurus hudsonicus grahamensis (AZ))
Species Id 050811
Date 20 OCT 97
LIFE HISTORY:
REPRODUCTION
Mount Graham red squirrels predominantly nest in cavities
within snags (66%), followed by bolus nests (26%), and
ground nests (7%). Nest location heights averaged 8.3 m
(+/- 0.5 m). Nest tree DBH averaged 50.5 cm (+/- 2.5
cm) (Point, et al., 1997) *07*.
BEHAVIOR
Red squirrels (Tamiasciurus hudsonicus) demonstrate a rise
in body temperature before leaving resting sites. Their
body temperature is depressed while resting in protected
sites, but they rely on agility and alertness to avoid
predation once outside. Thus, a raised body temperature
is important for activities which require less protected
environs than occur in resting sites
(Buskirk, et al., 1988) *05*.
LIFE HISTORY CODES
1400 Reproduction: Viviparous/Ovoviviparous (live bearing)
3702 Birthing/Egg Laying Site: Snag
3720 Birthing/Egg Laying Site: On the ground
4700 Nest Tree Height: < 10 Ft (< 3m)
4705 Nest Tree Height: 10-50 Ft (3-15m)
4799 Nest Tree Height: Specified in Comments
4815 Nest Tree DBH: 12.1-20 in. (30.6-50.8cm)
4820 Nest Tree DBH: > 20 in. (> 50.8cm)
4899 Nest Tree DBH: Specified in Comments
REFERENCES FOR LIFE HISTORY CODES - 07 and 10
Life History - 1
BISON-M - Management
Species: Mt. Graham Red Squirrel
(Tamiasciurus hudsonicus grahamensis (AZ))
Species Id 050811
Date 20 OCT 97
MANAGEMENT:
RESULTS MANAGEMENT PRACTICES
Adverse Habitat Mgt; recreational dev.; camp/picnic areas
Adverse Logging; general
Adverse ANIMAL DAMAGE CONTROL (ADC) Chemical
Adverse ADC: Zinc Phosphide, above ground (grain bait)
REFERENCES FOR ADVERSE MANAGEMENT PRACTICES - 04, 08 and 09
COMMENTS ON ANIMAL DAMAGE CONTROL PRACTICES
Zinc phosphide is highly toxic to rodents (USDA, 1994)*08* and
(Johnson and Fagerstone, 1994)*09*.
STATUS OR CONDITION OF A POPULATION WITHIN NORTH AMERICA
1993: In 1993, a Federal Recovery Plan was approved for this
species (AGFD, 1995) *02*.
1995: Mount Graham Red Squirrel
(Tamiasciurus hudsonicus grahamensis).
Arizona State Endangered. Population seriously threatened
by cumulative effects of approximately 100 years of human-related
activities, including timber harvest, recreational development
and possibly competition from tassel-eared squirrels (Sciurus
aberti) introduced from northern Arizona. The proposed
development of an astrophysical complex currently poses
additional threats. Critical Habitat proposed for high elevations
in the Pinaleno Mountains (AGFD, 1995)*01*.
ARIZONA
1996, Threats include: cumulative effects of a century of
human-related activities, including timber harvest, recreational
development, development of an astrophysical complex, and
possibly competition from introduced tassel-eared squirrels
(Sciurus aberti) (AGFD, 1996)*04*.
Management Practices - 1
BISON-M References
Species: Mt. Graham Red Squirrel
(Tamiasciurus hudsonicus grahamensis (AZ))
Species Id 050811
Date 20 OCT 97
REFERENCES:
01 Arizona Game and Fish Department. February, 1995.
Status Designations Notebook. Heritage Data Management
System (HDMS). Phoenix, AZ.
02 Arizona Game and Fish Department. November 9, 1995.
Recovery Plans and Conservation Agreements for Listed
and Candidate Species in Arizona. Heritage Data Management
System (HDMS). Phoenix, AZ.
03 Arizona Game and Fish Department. November 9, 1995.
Special Status Animals and Plants with Designated or
Proposed Critical Habitat in Arizona. Heritage Data
Management System. Phoenix, AZ.
04 Arizona Game and Fish Department. March 16, 1996.
Wildlife of Special Concern in Arizona (Public Review DRAFT).
Phoenix, AZ, 85023-4399.
05 Buskirk, Steven W., Henry J. Harlow, and Steven C.
Forrest. 1988. Temperature Regulation in American Marten
(Martes americana) in Winter. National Geographic
Research 4(2):208-218.
06 Arizona Game and Fish Department. June, 1996.
Natural Heritage Program. Phoenix, AZ.
07 Point, E.A., T.E. Morrell, and J.C.Devos. 1997.
Nest Site Characteristics of Sympatric Mount Graham Red
Squirrels and Abert Squirrels. In Abstracts of the 30th
Joint Annual Meeting of The Wildlife Society, New Mexico
and Arizona Chapters, and American Fisheries Society, Arizona
-New Mexico Chapter. Feb., 1997.
08 USDA. April 1994. Animal Damage Control Program; Final
Environmental Impact Statement. US Dept. of Agriculture,
Animal and Plant Health Inspection Service. 3 volumes.
09 Johnson, G.D. and K.A. Fagerstone. 1994. Primary and
Secondary Hazards of Zinc Phosphide to Non target
Wildlife - A Review of the Literature. USDA-APHIS,
DWRC Research Report No. 11-55-005.
10 Schmitt, Greg. September, 1997. Endangered Species
Biologist. New Mexico Department of Game and Fish. Santa Fe, NM.
Pers. Communication.
