284 NORTH AMERICAN FAUNA 61, FISH AND WILDLIFE SERVICE 



are ingested together with the soft digestible parts, are causing 

 the sea otter some difficulty. Do some individuals succumb 

 through injuries caused by such materials? How are the tissues 

 responding to the demands for taking care of such rough fare? 



It is obvious that the sea otter does not meticulously select only 

 the soft parts. Apparently, it relies on crushing the shells with 

 its teeth (and the teeth have developed enormously to meet the 

 need) and then proceeds to swallow a considerable portion of 

 shells, tests, and spines. Even the byssus of the mussel, often 

 with pieces of stone or coral attached, is swallowed. In one in- 

 stance, pebbles made up 21.8 percent of the contents of one scat. 

 All such material passes through the alimentary tract, therefore 

 it would not be surprising if serious injury occasionally resulted. 

 It would be interesting to know how many of the sea otters 

 washed up on the beach in Alaska have internal injuries similar 

 to the gastric perforations reported by Miss Fisher. 



On the other hand, from the standpoint of the sea otter popula- 

 tion as a whole, the organism appears to be coping with the de- 

 mands successfully. Rate of reproduction is slow — one young per 

 year — yet, when released from the pressure of the fur trade, the 

 sea otter has multiplied rapidly. 



Distribution and Numbers 



It is well known that in primitive times the northern sea otter 

 ranged along all of the southern Alaskan coast, including the 

 Aleutian chain and Alaska Peninsula. It ranged southward, evi- 

 dently intergrading with the southern form at some unknown 

 point, and the southern form ranged from this point southward 

 as far as the coast of Baja California. The northern sea otter 

 also occurred in the Commander Islands and southward into the 

 Kurile Island chain, and they were numerous about the Pribilof 

 Islands. Littlejohn (1916) reported schools of 400 sea otters 

 in the early days of hunting along the Kuriles. 



The decline of the sea otter population is a striking instance 

 of the near extinction of a species through unregulated commer- 

 cial exploitation. Before the coming of the white man, sea otters 

 were extremely numerous and the skin was used by the Aleuts 

 for clothing and (according to the chief of Atka Village) for a 

 lining of the interior of their underground huts. We found Aleut 

 mummies in a cave on Kagamil Island that w ere wrapped, in part, 

 in sea otter skins. 



When the Pribilofs were first visited, the sea otters were abun- 

 dant. Preble and McAtee (1923), quoting Elliott and Littlejohn 

 (1916), state that 5,000 sea otters were killed in the first year of 



