242 ECONOMIC MAMMALOGY 



pus, skate, starfish and flounder. 18 Of 100 stomachs, 10 per cent were 

 empty; 9 per cent contained only traces of food; fish, 93.58 per cent, 

 largely noncommercial; I contained 64 singing fish (6 pounds) ; only 

 2 contained salmon. 18 " 8 Some following remarks on the relation of 

 sea-lions to fish will apply with equal force to the seals. Dall has listed 

 eight species of marine mollusks taken from stomachs of the bearded 

 seal (Erignathus barbatus). In addition to the value of their skins 

 and oil, the flesh of seals is often eaten. 



Sea-lions also are accused of being destructive to the fisheries. Red- 

 ding said that in 1887 there were three thousand seals and sea-lions 

 at the entrance to Golden Gate Harbor, San Francisco, each eating 

 from twenty to forty pounds of fish daily. He seemed to consider them 

 the cause of the decrease in the number of salmon, yet he admitted the 

 difficulty of preventing Greek and Italian fishermen ''from capturing 

 every fish that comes into the harbor," 20 which assuredly must have 

 had something to do with the decrease in the salmon run up the river. 

 The fact is that an examination of the stomachs of California sea- 

 lions does not make a very strong case against them. An even more 

 significant fact is that both seals and sea-lions had lived in large num- 

 bers in the vicinity for unknown ages, and yet the salmon remained 

 very abundant until human fishermen of the Pacific Coast began to 

 supply the world with canned salmon. 21 Hence the justice of the fisher- 

 men's demand for the extermination of seals and sea-lions is very ques- 

 tionable. 



Eight stomachs of sea-lions killed by fishermen during the salmon 

 season, because they were believed to be feeding on salmon, were 

 examined by Dyche, who found no fish remains in them. Afterwards 

 he killed twelve sea-lions and found seven of the stomachs to be filled 

 with squid, one with octopus, four nearly empty, except a few squid 

 beaks. Later two more were examined; he found one full of squid, 

 the other full of octopus. He says that when sea-lions were abundant, 

 about fifty years ago, salmon were also much more abundant, and that 



18 Scheffer, Precarious status of the seal and sea-lion on our northwest coast, 

 Journ. Mammalogy, ix, 10-16, 1928. 



"~* Scheffer and Sperry, Food habits of the Pacific harbor seal, Phoca richardii, 

 Journ. Mammalogy, xn, 214-226, 1931. 



19 Dall, Report of the Canadian Arctic expedition, 1913-7918, vin, Part A, Mol- 

 lusks, 1919 ; Journ. Mammalogy, i, 246-247, 1920. 



^Redding, Causes of the decrease of salmon in the Sacramento River, Bull. 

 U. S. Fish Comm., vii, 57-58, 1887. 



21 Dall, On the preservation of the marine animals of the northwest coast, Ann. 

 Rept. Smithsonian Inst. for 1901, p. 687. 



