Maintenance

They keep warm and dry because of a layer of soft thick fur next to the skin called under-fur. Guard fur on top of the under fur is much thicker and protects the bears from moisture, insect bites and stings; also acts as camouflage.**SELF-GROOMING:** Little has been reported, but scratching with a hind foot, and licking of the paws, has been described. ( [] )

In addition to self grooming, American black bears, //Ursus americanus,// hibernate for and extended period of time. The bears can hibernate for 4 to 6 months without eating, drinking, remaining basically immobile and do not expel urine or feces. The black bear has a unique biological mechanism for processing urea, which is involved in the metabolism of nitrogen, which allows for this extended hibernation. (Lohuis et al., 2005)


 * References:

Lohuis, T., Beck, T. & Harlow, H.,** 2005. Hibernating black bears have blood chemistry andplasma amino acid profiles that are indicative of long-term adaptive fasting. //Canadian Journal of Zoology.// **83,** 1257–1263.

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