BEAR, BLACK

Under construction May 2011

BLACK BEAR

Ursus americanus

GUARD HAIR

Length: max 80mm (Mayer 1952), up to 100mm (Tumlison 1983), max 108mm (Hicks 1977), 100-110 mane hairs (Adorjan and Kolenosky 1969), 108mm max (Moore et al 1974), 90-100 mm up to 120mm near belly (ASM #1), 55-65mm (ASM #2), 45-70 (ASM #3), 80-290mm (ASM #4), 90-100mm (ASM #6), 60-70mm (ASM #7)

Diameter Range: 100-260 microns (Brown 1942) 100 microns (Mayer 1952). 100-107.5 (ASM #1) 62.5 microns (ASM #3)  75 microns (ASM #7) 153 microns max (Hicks 1977, same as black bear he says) 

Medullary Index: 0.27 (Brown 1942), 0.32 (ASM #1), 0.24 (ASM#3) 0.4 (ASM #7)

Medulla: fragmentary in basal region (Brown 1942). 30-35 microns (ASM #1). 15 microns (ASM #3). 30 microns (ASM #7) ASM samples show a medulla that is continuous and largely air filled with rounded stacked single cells that span the width of the medulla that are barely visible. In general it is difficult to make out much of the details of the medulla, though viewing in polarized light can be helpful.

Color: Brown pigmentation throughout the cortex, getting lighter closer to the cuticle.

Scales: From a cast made with Duco: The scales appear as wide individual shingles that overlap. Each of the overlapping scales has a unique outline, looking similar to torn paper edges placed on top of one another with multiple jagged  points per scale. There appears to be one or two scales per width (ASM samples) Scales have rough margins, spaced more widely at base and closer near the tip.  Scales 1-3 across width of hair as seen under the microscope (Adorjan and Kolenosky images, 1969).  In one sample, the scale edges looked smooth near the base.

UNDERFUR

Length: 45-50mm (Adorjan and Kolenosky 1969), 20-30mm (ASM #1), 5-15mm (ASM #2), 5-10mm (ASM #3), 10-12mm (ASM #4), 85-90mm (ASM #6 could that be right?? Specimen is a glacier bear), 50-60mm (ASM #7)

Diameter Range: 44-108 microns (Brown 1942). 37.5-42.5 (ASM #3)

Medullary Index: 0.20 ave (Brown 1942). 0.30-0.26 (ASM #3)

Medulla:  10 microns wide on ASM#3 in the form of a uniserial ladder with air filled spaces between the square and disk shaped cells.  Some samples show interrupted medulla, others none at all.

Color: Pigment in cortex but not medulla (Brown 1942). Red-brown pigment is in the medulla and the cortex (ASM #3).

Scales: Mostly diamond-petal shaped like a snakeskin, but can also be stacked crown shaped.

Macro Qualities: 3.9-4.9 feet long (Forsyth 1999) 60” long nose to tail, 29” high at the shoulder.  Color can range from jet black to almost white.  (ADF&G 2008)  Brown or cinnamon colored bears are sometimes seen in Southcentral Alaska and the mainland, blue glacier bears are found in the Yakutat area, and most of the bears in southeast Alaska are black, perhaps with a white patch on the chest. Blue bear or Glacier bear is a smoky blue or blue-grey rare recessive coloration most often found in the Yakutat area (Rearden 1981)  Glacier bear rug I-B-255 is 65” long nose to tail.  Fur is a mix of creams and grays, no banding.  Darker paws and head, slightly reddish toes.  Guard hairs are mostly white and black, and underfur is mostly brown and white.  (ASM #6) Guard hairs wavy, underfur may appear in large closely matted bunches (Adorjan and Kolenosky 1969)  Kermode are a rare white or pale (but not albino) coloration.

Cultures: For example: European market for the fur on certain ceremonial military hats (shako, busby, bearskin).  Good “serviceability” (Bachrach 1953)  Fur of brown and black bears often used on ornamentation of masks. Emmons (1991) The Tlingit Indians University of Washington Press, Seattle. p.175

Notes: ASM #1 is a pelt from ASM off site storage, ASM #2 is a small pelt (cub?) from ASM off site storage, ASM #3 is from the education collection pelt ring, ASM #4 is Alaska State Archaeologist Dave McMahan’s reference set, ASM #5 is from an old slide in the ASM conservation lab, ASM #6 is from a glacier bear I-B-255 at ASM off site storage, ASM #7 is from the Juneau-Douglas City Museum fur touchboard.

Troubleshooting: Black bear and brown bear hairs can be difficult to distinguish.  Narrower medulla than most other carnivores or the bison.  Hairs are longer than otters and fur seals who also have a narrow medulla like the black bear.  (Mayer 1952)

Range: Mostly interior, southern and southeast panhandle, NOT on the Aleutian Islands (Forsyth 1999)  NOT on the North Slope (Rearden 1981)  Generally in the forested areas of the state.  Not on the Seward Peninsula or Yukon-Kuskokwim Delta, or north of the Brooks Range.  Absent from many islands, including Kodiak, Admiralty, Baranof, Chichagof and Kruzof (which are inhabited by brown bears)  (ADF&G 2008)

Names: Family Ursidae (the ursids) One subspecies Kermode is often almost white is known in the British Columbia area of Canada.  Subspecies Cinnamomum is not known in Alaska.  Blue bears or Glacier bears are black bear color phases. 

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