THE SEA OTTER IN THE EASTERN PACIFIC OCEAN 275 



gether produce iron sulfide, the putrafactive changes in the in- 

 testine produce the H2S). 



7. I have examined the stomachs of more than 200 otters that 

 showed symptoms of enteritis at death. None has contained food. 

 The stomach may contain from 10 to 50 ml. of liquid which may 

 be pinkish, reddish brown, or yellowish. The mucosa may show 

 inflammation. 



8. Weight loss, probably caused by dehydration and starvation, 

 characteristically accompanies enteritis. A captive juvenile male 

 (59-159), that died showing symptoms of enteritis, lost 26 per- 

 cent of its body weight in 3 days. 



It appears probable that a Clostridium organism is present in 

 all animals and that it becomes active when the animal is sub- 

 jected to stress, such as starvation or nervous tension. Unsatis- 

 factory conditions in captivity, such as lack of water, may cause 

 such nervous tension. In captivity, I have observed that animals 

 given access to an abundant supply of clear water and abundant 

 food have not been subjected to sufficient stress to develop enteritis. 

 As pointed out elsewhere, animals which show symptoms of 

 enteritis when captured may recover in captivity when given 

 abundant food and water. Stress may be caused in captivity if the 

 fur becomes dirty and the animal is chilled. Extreme anxiety ac- 

 companies chilling, a large intake of food may occur but unless 

 the fur condition can be improved the animal experiences stress; 

 enteritis usually develops, and is followed in a few hours by death. 

 In the wild, lack of nourishing food and accompanying rough, 

 stormy seas appear to cause stress that results in enteritis and 

 terminates in death. 



Additional laboratory examination of specimen material taken 

 from sick or dying sea otters is needed before we can attain a 

 proper understanding of the relationship between enteritis and 

 the trematode Microphallus pyrum, and the bacterium, Clostri- 

 dium, in the sea otter. 



Infection and liver degeneration 



Dr. Dean Jensen, College of Veterinary Medicine, Colorado State 

 University, kindly made a study of pathological tissues obtained 

 from animals found dead or dying at Amchitka. 



An adult female (D7-57), having well-worn teeth, weighed 56 

 lb. (25.4 kg.) when captured alive on 1 December 1957. Her 

 weight at death, 6 December 1957, was 47 lb. (19 kg.). This animal 

 lacked energy and ate sparingly during the period of captivity. 



