84 



NORTH AMERICAN FAUNA 68 



Figure 45. — A captive adult male sea otter from Amchitka Island pounds a 

 clam, held between his forepaws, against a rock resting on his chest. 

 Usually the head is held erect (above) but not infrequently it is extended 

 during food pounding behavior (below). (KWK 67-15-7 above, 67-14-30 

 below) 



hard-shelled organisms or by fish they did not care for. Also 

 (Kenyon, 1959), a sea otter pounded a drain cover with a rock 

 when the cover frustrated a desire to explore the drain. I consider 

 the sea otter's tool-using behavior, as derived from chest-pounding. 



