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NORTH AMERICAN FAUNA 68 



strated that the local abalone beds were seriously decimated but 

 not entirely eliminated by sea otter predation. 



In a public statement, additional information was given by 

 Cox (California Senate, 1963) : 



In 1956 we went into Shelter Cove right off Monterey and over a period of 

 several days tagged 513 abalone. One year later we came back in the area and 

 we spent approximately three days searching and we found five abalone . . . 

 one of which had a tag. The area where we were able to collect five hundred 

 abalone in an hour we couldn't find any. On one dive I brought up over two 

 dozen broken shells . . . characteristic of broken ones of the sea otters. We 

 were told ... by the caretaker, that a herd of sea otters had spent the 

 winter in this cove ... I had been called to task for not reporting this. . . . 

 However, I felt this was not an adequate experiment. 



In a recent study of sea otter feeding habits on the California 

 coast, Ebert (1968) concluded that ''sea otters exert a profound 

 influence upon benthic communities." 



During 1963, abalone fishermen in San Luis Obispo County, 

 California, complained that sea otters were destroying the abalone 

 resource of that area. Claims of spectacular damage to abalone 

 beds appeared in many newspapers. In response to these com- 

 plaints a hearing was held at the City Hall, San Luis Obispo, on 

 19 November 1963. At this hearing Mr. Harry Anderson, Deputy 

 Director of the California Department of Fish and Game, presented 

 testimony to the California Senate Fact Finding Committee on 

 Natural Resources. He compared commercial landings of abalones 

 in certain areas before and after sea otters were present in these 

 areas. In 1961 when sea otters were present **the catch was over 

 1,550,000 pounds, by far the largest catch of any year in the 

 10-year period." He indicated further that competition among 

 abalone fishermen has increased greatly. In 1928 there were 11 

 licensed commercial abalone fishermen in California. The number 

 has increased to 505 in 1963. Since the abalone resource is limited, 

 it becomes apparent that the individual fishermen can expect to 

 obtain fewer abalones than when competition among them was 

 less. It was concluded that "all the evidence we have indicates 

 that the sea otter has not seriously harmed or threatened the 

 abalone resource." 



The data indicate that the depletion of food resources at Am- | 

 chitka has resulted in an abnormally high winter die-off of sea 

 otters as well as a population of undersized animals (see Mortality 

 Factors and Body Measurements). Evidence from California re- 

 veals that when sea otters feed for an extended period in a limited 

 area they may seriously deplete local populations of their prey 

 species. 



