Winter mortality of common loons in Florida coastal waters.

Diagnostic findings are presented for 434 common loons (Gavia immer) found sick or dead on Florida beaches from 1970 through 1994, primarily during the months of December to April. The most commonly recognized problem was an emaciation syndrome (66%), followed by oiling (18%), aspergillosis (7%), trauma (5%) and miscellaneous disease entities (1%). The cause-of-death for 3% of the birds was not determined. Many of the carcasses examined (n = 173) were obtained during an epizootic which occurred from January to March of 1983 in which more than 13,000 loons were estimated to have died. An emaciation syndrome, characterized by severe atrophy of pectoral muscles, loss of body fat and hemorrhagic enteritis, was the primary finding in this epizootic. It was postulated to have a complex etiologic basis involving synergistic effects and energy costs of migration, molting and replacement of flight feathers, food resource changes, salt-loading, intestinal parasitism, environmental contaminants, and inclement weather.

Psoroptic scabies in bignorn sheep (Ovis canadensis mexicana) in New Mexico.

Prior to 1978, no reports were made of scabies lesions or mites recovered from any Mexican bighorn sheep (Ovis canadensis mexicana) examined in the San Andres National Wildlife Refuge in southern New Mexico. In 1978, all of five rams harvested by hunters had live mites of the genus Psoroptes and active lesions of scabies in their ears and/or on their bodies. Deaths due to scabies were not documented during this outbreak although aerial helicopter surveys conducted in March, June and September, 1979 recorded less than half the sheep observations of five previous and similarly conducted surveys. After measurement of the length of the outer opisthosomal setae of the male mites, they appear to be Psoroptes ovis (Hering), the common scabies mite of domestic sheep, cattle and horses. Final specific determination must await proposed transmission studies with domestic livestock.