SQUIRREL, ARCTIC GROUND

Under Construction May 2011

ARCTIC GROUND SQUIRREL

Spermophilus parryii

GUARD HAIR

Length: 15-20mm and 35mm tail (ASM #2)

Diameter Range: 110 -125 microns (ASM #1) 92.5-100 (ASM #2)

Medullary Index: 0.77 (ASM #1) 0.89-0.8 (ASM #2)

Medulla: 85-90 microns (ASM #1) Medulla along the hair changes from the root to the tip. At the root it is uniserial ladder. Further along it is absent, then interrupted. As the hair widens the medulla appears as fused cells of bubble-like letterforms resembling H,K,Y etc, turning into squat bubble-like side by side M shapes. The cells are widely spaced with some brown-red pigmentation scattered throughout. As the hair widens further, these bubble-like letters appear stretched wider across the width of the medulla and are closely spaced. The perimeter of the medulla looks like repeating “V” shapes in the widest section.

Medulla from the ASM #2 pelt ring sample shows a completely different medulla; one that is continuous and completely filled with dark brown pigmentation, so dark that it is not really possible to distinguish features in the medulla except in locations where the pigmentation is slightly a lighter red-brown. Where the pigmentation is lighter it is possible to a medulla that appears to be formed of irregularly shaped translucent globules that are somewhat interconnected.

Color: Brown-reddish coloration is present in the very tip and by the root- absent in the widest area (ASM #1) In ASM#2 samples the fibers are consistently pigmented throughout the medulla and cortex, with a narrow margin by the cortex.  Easier to see banding on the macro view.

Scales:  Scales have a very irregular margin that is torn-paper like with very jagged edges. There is one scale per width of the medulla (ASM)

UNDERFUR

Length: 5-10mm (ASM #2)

Diameter Range: 12.5-20 microns (ASM #1) 20 microns  (ASM#2)

Medullary Index: 0.5 (for samples with medulla present)

Medulla: Fragmentary in some samples, Uniserial ladder with cells that slightly taper giving a trapezoidal shape, or like a back pocket of a pair of Levi’s jeans (about 7.5 microns in width).Other samples did not show any medulla.

Color: light streaky brown in center of the fiber and lessens towards the cuticle.

Scales: stacked crowns

Macro Qualities:

Cultures: Reference on how to process the skins in Edna Wilder (1976) Secrets of Eskimo Skin Sewing.  University of Alaska Press, Fairbanks.

Notes: ASM #1 is taxidermy mount UA/UC 407 at the ASM off site storage, ASM #2 is from a pelt on the ASM education collection pelt ring.  The MacBride Museum in Whitehorse, Yukon Territory, Canada reportedly has a cape made from black ground squirrel pelts with glass beadwork on cloth that belonged to Kate Carmacks.  Black color is the default in the Carcross/Teslin/Tagish area on the border between Alaska and Canada.  Normal markings like barring are present, just very dark.  (Valery Monahan, objects conservator for the Yukon Government)

Troubleshooting: Squirrels (Arctic Ground, Northern Flying and Red) have shorter guard hairs than the other rodents observed, with a length not exceeding 30mm except on the tail where it might reach 35mm on the arctic ground squirrel and 45 mm on the red squirrel.  Underfur of squirrels also may have a distinct brownish tip after a seemingly colorless shaft for most of its length.  Squirrels may also have intermediate sized hairs with long narrow interrupted or uniserial ladder medulla near the base until the shield where the medulla looks like tire tread.  Distinguishing among the squirrels: arctic ground squirrel underfur has no medulla.  Northern flying squirrel is gray in color?  To distinguish squirrel from muskrat, observe the underfur.  Often, muskrat underfur has a gray appearance to the naked eye with a hint of cool lavender purple.  Under magnification, the muskrat underfur often has no medulla, or a few fibers will have an interrupted medulla. 

Range: Very common around Carcross (Woodford 2010).  NOT in Southeast, South Central, or Y-K Delta area.

Names: Order Rodentia (the rodents)  Older publications may refer to “Parry’s Spermophile”  Also called parka or parky squirrel.  Might be called sic sic puk.

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