THE SEA OTTER IN THE EASTERN PACIFIC OCEAN 109 



in California sea otters, it is rarely observed in the parts of Alaska 

 where I have v^atched sea otters feeding or in Soviet waters 

 (Barabash-Nikiforov, 1947). At Amchitka, I have twice observed 

 subadult otters pounding a chunk of coralline algae held between 

 the forepaws against another resting on the chest. This behavior 

 appeared, however, to be play as the animals did not attempt to 

 find food in the algae after breaking it but discarded the material 

 after a few minutes of intermittent pounding. 



That Alaska sea otters are capable of using the pounding tech- 

 nique was demonstrated by a captive taken at Amchitka Island. 

 Soon after Susie had become accustomed to captive conditions at 

 Seattle, several small stones and whole butter clams (Saxidomus) 

 were placed in her pool. Although she used a stone as an anvil on 

 which to break the clams, she used it in other ways too. The stone 

 was also held in the paws and used as a hammer. Also, if a large 

 number of clams were given to her she often neglected to obtain 

 the stone but pounded the clams against each other (fig. 60). 

 Clams, sea urchins, fish, and rocks were pounded against the 

 cement-constructed side of the pool (fig. 59). 



Figure 60. — Clams (Saxidomus) were broken open by pounding one against 

 another held on the chest. If a rock was handy, this captive otter pounded 

 clams against it. Clam meats are scooped from the shell with the tongue 

 and lower incisors. (KWK 57-22-32) 



