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NORTH AMERICAN FAUNA 68 



Various reports of poaching by foreign nationals in the outer 

 Aleutian Islands are not confirmed. 



The problem of illegal killing of sea otters may be of more 

 importance in California. Captain Howard Shelby of the California 

 Department of Fish and Game reported that in one period (late 

 1957 and early 1958) in the Monterey area alone 18 dead otters 

 were found. ''Some had a hole clear through them, either spear or 

 bullet wound." He said further that ''it's my opinion that there 

 are people and there are groups of people who do definitely shoot 

 this animal. Then there are quite a group that target practice at 

 anything." (California Senate, 1963) 



Summary 



1. Few sea otters were found dead on Amchitka beaches in 

 the period 1938-40. The first report of significant natural mortality 

 was made in the spring of 1948 when "more than 100" otters were 

 found dead on beaches. Since the late 1940's significant late-winter, 

 early-spring mortality was observed when biologists visited 

 Amchitka. During five study periods from 1956 to 1963, data 

 were obtained from 311 otters found dead or dying on beaches of 

 the eastern half of Amchitka Island. 



2. The greatest number of otters usually died in the month 

 of March but considerable mortality also occurred in February, 

 April, and May. In this late-winter, early-spring period about 

 three-quarters of all annual mortality occurred. 



3. Approximately 70 percent of the late-winter, early-spring 

 mortality occurred among juveniles deserted by mothers. The other 

 30 percent of dead animals were predominantly adults showing 

 signs of age. 



4. During the period of stress caused by storms, mothers 

 deserted their large juveniles at an earlier age than they did at 

 other seasons. They appeared to do this because it was difficult for 

 a mother to obtain sufllicient food to satisfy both herself and the 

 large juvenile. Few very small pups were found dead even though 

 they were present in the population at all seasons. 



5. Mortality was usually greater among males than among 

 females. Among juveniles this disparity was greater than among 

 adults. Males in captivity were found to be less hardy than females. 



6. Vigorous adults were able to obtain adequate nourishment 

 from high-calorie foods, such as fish and octopus. These organisms 

 were seldom obtained by juveniles and aged animals. 



7. A high percentage of juveniles and aged animals found 



