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Native Californian, biologist, wildlife conservation consultant, retired Smithsonian scientist, father of two daughters, grandfather of four. INTJ. Believes nature is infinitely more interesting than shopping malls. Born 100 years too late.
Showing posts with label age determination. Show all posts
Showing posts with label age determination. Show all posts

Friday, August 30, 2013

My neighborhood bears



As if you haven't seen enough bears on this blog already, here is the full cast of characters -- the bears in my neighborhood.

I've gotten to know them pretty well, and this shows how I tell them apart. 

Like people, they get a bit gnarly looking with age.

So, they are easier to identify when they get old.

My estimates of age are based on body size and photos of two of these critters taken some years ago.

If you are interested in this sort of thing, here are some useful references.


Alt, G.L. 1980. Rate of growth and size of Pennsylvania black bears. Pennsylvanian Game News, 51(12)7-17.

Marks, S.A. and A.W. Erickson. 1966. Age determination in the black bear. Journal of Wildlife Management, 30:389-410.

Rausch, R.L.. 1961. Notes on the black bear in Alaska with particular referecne to dentition and growth. Zeitschrift fur Saugetierkunde, 26(2):65-128.