ABSTRACT
Diseases caused by pathogenic bacteria, either alone or in conjunction with parasitic or traumatic damage to allow the bacteria entrance to tissue, are probably the main cause of disease and death in marine mammals. Bacterial infection involving the skin and underlying structures often occurs following traumatic injury. Microscopic examination of bacterial skin lesions reveals a spectrum of histopathologic features. Isolates were cultured and identified from a large number of animals that died of septicemia. Genital tract infection was the apparent cause of stranding and death of two adult female California sea lions. Bacterial diseases, alone or in concert with parasitic infections, appear to be the most serious problem encountered in the study of marine mammal diseases. This is an especially severe problem in captive animals, particularly cetaceans, and is also responsible for or associated with the stranding and death of numerous pinnipeds along the southern California coast.
