FOX, ARCTIC

Under Construction May 2011

ARCTIC FOX

Alopex lagopus

GUARD HAIR

Length: 70-80mm (Brown 1942), 40-50 (Adorjan and Kolenosky 1969), 75-85 (Furskin 2006), 20-35mm (ASM #2 lower back), 80-85mm (ASM #2 belly), 60-70mm (ASM #2 tail)

Diameter Range: 56-132 (Brown 1942). 37-65 (ASM #2)

Medullary Index: 0.61 ave (Brown 1942) 0.69 (ASM #2)

Medulla: Continuous with large dark brown granules scattered between the cells (Brown 1942). Continuous appearing with discrete stacked disk shaped cells, some with spaces between and other closely stacked. These disk shaped cells appear to be angled (like wedges) in some areas.  Medulla is 15 microns in present sample, and the height of the average disk shaped cell is 5 microns (ASM #2). Uniserial ladder and no medulla near base (Furskin 2006).

Color: Can be white, dirty brown or slate gray (Brown 1942). White (ASM#2).

Scales: Petal-like with short tips (Furskin 2006)  One sample showed flower-petal like scales that were consistent along the whole length, but most ASM samples showed very long pointed petals at base turning into fat petals with smooth edges along shaft, becoming torn paper-like edges near the tip with much closer scale margins near tip.  It seems that some of the intermediate or underfur hairs will show the same petal-shaped scales along the entire length, while the guard hairs will show the change in scale pattern along the length that is typical for canids.  This is also reflected in the photos in Adorjan and Kolenosky (1969)

UNDERFUR

Length: 20-30mm (Brown 1942), 15-30mm (Furskin 2006), 18-22 mm (ASM #2 lower back), 40-50mm (ASM #2 belly), 25-30 (ASM #2 tail)

Diameter Range: 20-60 (Brown 1942). 25 (ASM #2)  15 microns near base 50 microns closer to tip, base has a very long taper.

Medullary Index: 0.57 ave (Brown 1942) 0.5 (ASM #2)

Medulla: No pigment (Brown 1942). 12.5 microns, continuous appearing as vacuolated with discrete discus shaped cells stacked, some with spaces between and other closely stacked- identical to guard hairs. The medulla is similar to uniserial ladder, but the cells are not very square. Average height for individual cells is 5 microns.  More elaborate medulla near the fatter tip, and gets simpler in the long taper near the base. (ASM #2)

Color: Absent in the cortex.  Should always be white. (Brown 1942). White (ASM#2) Furskin reports that the underfur is always brown  (Furskin 2006)

Scales: Seem to be petal shaped with sharp points the entire length of the hair. Unusual for canids.

Macro Qualities: 2.5 – 3.9 feet long (Forsyth 1999)  43” long (Including the tail, which is around 15)  Come in both a white and a blue color phase.  Blue phase more common on Aleutian and Pribilof Islands.  Summer phase tends to be brown, but can be dark gray.  Blue phase foxes are dark or charcoal colored year round but slightly lighter in winter.  Newborn pups have short velvety dark brown fur.  (ADF&G 2008) 30” long plus 13” tail (ASM #2) The blue phase of the Arctic fox is actually a dark brown with a bluish tinge, fading to a reddish brown in the spring. Rounded ear tips.  (Bachrach 1953) Guard hairs are curled near skin and straight near tip. Underfur is curled and always brown? (Furskin 2006)  ASM #2 has white underfur.  “The idea that a white fox turns into a blue fox in the summer is mistaken.  (however, summer phase arctic fox are often called blue, so what does Bacharach mean?) So is the idea that a cross fox is a cross between a red fox and a silver fox.  Blue fox ranching began in Alaska as early as 1865” Fair “serviceability” (Bachrach 1953)  Adorjan and Kolenosky (1969) describe the underfur as growing “bundled together to form cotton-like tufts” Samet (1950) says unprime arctic fox underfur will mat easily because there are not enough guard hairs to separate it.

Cultures: For example: Some native peoples do not sell the paws with the pelt but keep them for themselves (Bachrach 1953)  Yup’ik men hunted them (p.248)  Women used arctic fox for boot liners (p.258)  Fienup-Riordan (2007) Yuungnaqpiallerput: The Way We Genuinely Live.  Masterworks of Yup’ik Science and Survival.  Anchorage Museum Association. 

Notes: ASM #1 is conservation lab old set of slides, ASM #2 is from pelt I-B-35 in collection.  Furskin (2006) reports guard hairs can be dumbbell shaped in cross section in some parts of the shaft.

Troubleshooting:  Distinguished from polar bear whose shaft diameter is much larger  (80-200 microns, as opposed to fox at only 37-132microns) and medulla is skinnier (polar bear at 0.37 and Arctic fox at 0.61)

Range: NOT in Southeast, Kenai Peninsula or Kodiak Island (Forsyth 1999)  Treeless coastal areas from the Aleutian Islands north to Point Barrow and east to Canada (ADF&G 2008)

Names: Order Carnivora (the carnivores) Family Canidae (the canids) Also called a polar fox (Furskin 2006)  Summer phase seems to be called a blue fox.

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