Bear Lice

Lice are small, wingless insects that belong to the order Phthiraptera. Lice are parasites that have a symbiotic relationship with a host organism, such as a bear. As ectoparasites, lice live off the surface of the host in the spaces between the coat hairs. They have flattened bodies that measure approximately 1 to 2 mm in length. Body color includes white to pale yellow, with a darker orange to brown head.

  1. Life

    • Lice spread via direct contact between animals. Lice deposit eggs or nits that attach to the bear's hairs. A louse spends its entire life cycle on the host's fur. Two general types of lice include lice that chew on the body surface or suck blood.

    Impact

    • In this symbiotic relationship, chewing lice or mallophaga benefit by feeding on a bear's hair, skin and dander, or skin debris, at the expense of the bear host. While a few lice do not cause great problems, an infestation of biting lice can bring hair matting or loss, according to the Alaska Department of Fish and Game. Lice can cause a parasitic infection on the host animal or act as vectors for other diseases such as tapeworms.

    Types of Lice

    • Three types of mallophaga impact bears. Trichodectes spp. affects the American black bear (Ursus americanus). Trichodectes pinguis euarctidos, with a length of only 2 mm, have been found on black bears from British Columbia, Ontario, Montana, New York and Florida. Trichodectes pinguis pinguis is specific to the Asiatic black bear (Ursus thibetanus), according to the Journal of Wildlife Diseases. Grizzly bears and polar bears are also parasitic hosts.