ECOLOGY AND BIOLOGY OF THE PACIFIC WALRUS 



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which was cast ashore dead on the southern coast of St. Lawrence Island. The 

 entire respiratory tree of that female had been affected, leading to hepatization 

 (solidification) of most of the lungs. In addition, there was severe pleural and 

 pericardial inflammation with associated adhesions of the organs to the body 

 wall, fibrous thickening of the pericardial sac, and production of 7 to 8 L of 

 milky fluid in the thoracic cavity. The animal seems certainly to have died as a 

 consequence of those conditions. 



Conjunctivitis 



Apart from occasional damage to the eyes caused by tusk strikes, abnormal 

 ocular conditions seem to be uncommon in walruses. I observed only one case of 

 apparent conjunctivitis, in which one eye was swollen and nearly cemented shut 

 by a large amount of yellowish-green exudate. The animal, an old male, was 

 extremely emaciated and lethargic and had several open, bleeding wounds on its 

 body. Since this was in late March, at the end of the mating season, the leanness 

 and wounds probably were not related to the eye infection but to fights with 

 other bulls for display sites. 



Urethritis 



A 3-year-old male taken at Gambell on 1 June 1957 was affected by a general- 

 ized inflammation of the entire urogenital system, probably as a result of a 

 bacterial infection of long standing. The urethra was greatly inflamed, 

 thickened, and enlarged, and the testes and epididymides were swollen. The 

 penis also was inflamed and showed extensive osteonecrosis of the baculum. The 

 bladder contained a large amount of milky fluid. Conceivably, the kidneys also 

 had been affected, but they had been discarded before I was able to examine 

 them. The animal as a whole was emaciated, apparentiy having been severely 

 debilitated for some weeks or months. 



Pleuritis 



Two adults, a male and a female, showed generalized nodular fibrosis of the 

 visceral and parietal pleurae, indicative of chronic inflammation. About 3 L of 

 clear, serous fluid also were present in the thoracic cavity of the male; a lesser 

 amount was present in the female. Apart from those conditions, both animals 

 appeared to be normally healthy in all other respects. Probably, "the 

 inflammatory process began as the result of pneumonia or pneumonitis" (J. G. 

 Bridgens, personal communication). 



Pneumonia-Pneumonitis 



Minor inflammations of the respiratory tract seem to occur commonly in 

 walruses, for it is not unusual to see yellowish to greenish mucous expelled from 

 the nares (suggestive of catarrhal inflammation of the nasal membranes) or to 

 hear animals wheezing during respiration (suggestive of bronchial congestion). 

 A. C. Heinrich (personal communication), who spent several years as a school 

 teacher on Little Diomede Island, reported to me that "extremely thin animals 

 with large portions of the lungs decayed or atrophied . . . are sometimes found." 



Calves may be particularly susceptible to respiratory conditions. Five of 17 



