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Common bear afflictions
Skin
Sarcoptic Mange
Sarcoptic mange is rarely seen in black bears in Michigan. It is caused by a mite (Sarcoptes scabiei), which lives and burrows into the layers of the skin. The mites cause an irritation, resulting in the animal scratching and biting at the affected area and spreading the mites on its body. Hair loss, thickening and wrinkling of the skin, and scab formation are the result of the infestation.
Pantless Bears: Hair loss on the hind end of black bear, dubbed “pantless bear syndrome” is a phenomenon that has been observed in multiple states. While the experts don’t think that this is caused by mange, they are uncertain what the exact cause is. One theory is that it is related to nutrition and researchers are looking at mineral concentrations in black bear livers and correlating with coat anomalies. This condition doesn’t appear to affect the bear physically and as this is a skin condition the meat would be okay for consumption. We are interested in reports and photos of bear suspected of having mange or with pantless bear syndrome. We are also interested in collecting skin and liver samples from pantless bears. If you encounter one of these bears, please report it online.
Subcutaneous/abdominal cavity
Bear Filarial Worm
The bear filarial worm (Dirofilaria ursi) is commonly seen subcutaneously on the neck and the inguinal area and in the connective tissue around the aorta, kidneys, and the rectum. The worm does not cause any clinical disease but is easily seen by a hunter when field dressing the bear.
Intestinal tract
Bear Roundworm
The common intestinal roundworm seen in bears is the ascarid Baylisascaris sp. and it can occur throughout the intestinal tract. These nematodes do not cause any clinical disease but if the intestinal tract is cut/torn the roundworms will migrate out of the tract and into the abdominal cavity. They are large and are easily seen by a hunter when field dressing the bear.