BEAR, BROWN

Under construction May 2011

BROWN BEAR

Ursus arctos

GUARD HAIR

Length: 60-80mm (Brown 1942), max 70 (Hicks 1977 for grizzly), 90mm (Furskin 2006), 70mm max (Moore et al 1974), 40-48mm (ASM #1), 45-60mm (ASM #2), 110-120mm (ASM #4)

Diameter Range: 100-260 microns (Brown 1942). 100-120 (ASM#2). 87-95 microns (ASM #1) 140 microns (ASM #4) 80-175 microns (Furskin 2006)  153 microns ((Hicks 1977) 148 microns (Moore et al 1974)

Medullary Index: 0.27  Very slender medullary column.  0.2-0.27 (ASM#2). 0.34-0.36 (ASM #2) 0.28 (ASM #4)

Medulla: fragmentary in basal region, but continuous in mid shaft with robust rounded forms (Brown 1942). Medulla is fragmentary in basal (near skin) region and becomes continuous as it progresses along the shaft. The medulla is very narrow, and one cell wide throughout. The cells appear as variously shaped globules and disks with a narrow pocket of air between the cells. This pocket of air appears as a dark circle around each of the cells. The medulla has brown pigment running through it.

Fiber sample from ASM #1 shows a slightly different type of medulla where the cells are of inconsistent shape and size. There appears to be many small bubble-like forms throughout, that are surrounded by thin channels of air that give the medulla the appearance of having many black squiggly lines superimposed over elliptical stacked cells.

Color: Cortex is usually deeply stained by sparse pigments, color mostly due to stain (Brown 1942). Brown throughout the cortex and becoming translucent by the cuticle. Some hairs might look lighter brown on the base end.

Scales: Scales appear to be overlapping shingle-like with margins that are not jagged. Overall the scales appear to be wider than they are tall.  Almost triangular in shape. (ASM #4)  Grizzly bear scale photomicrographs from Moore et al (1974) show scales that are fairly widely spaced with rough edges along the entire length.  It may be that the scales are smooth edged near the base and rough edged near the tip.  More examination needed.

UNDERFUR

Length: ave 30mm curly (Brown 1942) 5-15mm (ASM #1) 10-15mm (ASM #2)

Diameter Range: 44-108 microns (Brown 1942) 15-28 microns (Furskin 2006) 42.5 microns (ASM #2) 60-70mm (ASM #4)

Medullary Index:  0.20  (Brown 1942) 0.11 (ASM #2)

Medulla: Absent in about 40% of the hairs studied by Brown.  When present, usually fragmented (Brown 1942). Narrow and fragmentary medulla (ASM #2)  Furskin 2006 failed to find a medulla in its samples.  Alaska State Museum samples often had a medulla, and medulla in general could show considerable variation.

Color: pigment in the cortex but not the medulla. Brown pigmentation throughout the cortex.

Scales: closely spaced, overlapping with toothy edges, maybe 2-3 scales across the width.  Mostly diamond petal shaped, but also a few stacked crown shapes.

Macro Qualities: 8.5 feet long (Forsyth 1999)  Larger than black bears and featuring a prominent shoulder hump.  Largest bears may be 10 feet tall when standing on hind legs.  Colors can range from dark brown to light blonde.  (ADF&G 2008) Good “serviceability” (Bachrach 1953) Guard hairs are darker near the tip and underfur is wavy and reddish brown (Furskin 2006)

Cultures: For example: 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 from the Sheldon Jackson Museum education collection surplus, ASM #2 is from the ASM education collection, ASM #3 is from a reference slide made by Alaska State Archaeologist Dave McMahan, labeled “grizzly”, ASM #4 is from the Juneau-Douglas City Museum 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: All of Alaska (Forsyth 1999)  All of Alaska except islands south of Frederick Sound in Southeast, west of Unimak on the Aleutian Chain, and the Bering Sea islands. 

Names: Family Ursidae (the ursids) Subspecies Ursus arctos horribilus is also called Grizzly and well-known in Alaska.  Subspecies Ursus arctos middendorffi is also called the Kodiak Brown Bear and is known in Alaska.  Moore et al (1974) calls the Grizzly bear ursus arctos imperator.

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