Two very young male beaked whales (Mesoplodon spp.) stranded on Ocean Beach in San Francisco on August 24, 1989. They were transported to Marine World Africa USA for treatment and rehabilitation. One lived for 16 days; the other for 25. Their clinical courses will be described elsewhere. The purpose of this report is to document the postmortem findings.

The first to die was the larger of the two. He had suffered from subcutaneous emphysema. The cause of death and the source of the emphysema could not be determined postmortem. There was pleural and interstitial emphysema and mild pleuritis, but no obvious defects in pleura or air ways were found. Unfortunately, the upper air ways had been removed prior to examination by the pathologists. The smaller of the two had a clinical history of blowing food out his blow hole. The cause of death was severe necrotizing bronchopneumonia with secondary overgrowth of Aspergillus. The fungal infection had spread to the bronchial lymph nodes and there was evidence of terminal disseminated intravascular coagulation. Complicating chances for rehabilitation were mild suppurative meningitis and necrosis of the right tail fluke secondary to vascular thrombosis that had possibly resulted from intravenous injections. He also had mild esophagitis and pharyngitis possibly from intubation for feeding. Although very young, and by clinical measures immunologically incompetent, both whales had histologic evidence of ability to respond to antigenic stimulation as evidenced by large numbers of plasma cells in sections of lymph nodes.

When stranded, both whales had ulcerative skin lesions that had begun to heal in captivity, and the larger one had mild parasitic gastritis. However, no severe underlying disease processes or congenital defects were found to account for the initial stranding.