66 THE FUR SEALS OP THE PRIBILOF ISLANDS. 



small pebbles, the total weight of which was 62.299 grams (2.2 ounces). M. Grebnltski 

 has suggested that the pebbles are swallowed in catching cephalopods, but this is 

 evidently incorrect for several reasons. The squid preyed u])on by the fur seal is a 

 deep-water species and does not cling to pebbles, being found near the surface; the 

 pebbles and beaks of squid are not found together, and tlie pebbles occur in the pups 

 who are eating nothing but milk. The most honest thing to say is that we really 

 don't know why seals swallow hard substances. 



From observations made by Mr. Clark during the season of 1896, he concludes 

 that seals remain in the water until' the food in their stomachs is digested, and that 

 this accounts not only for the fact that seals taken on landare invariably empty, but 

 for the presence of the band of swimming seals in front of every rookery. It would 

 also explain why females are never seen to come directly in from the sea, but emerge 

 from the fringe of idle seals along the shore, although this seems rather due to indi: 

 rectness of character, since we never saw a seal going directly out to sea, although 

 constantly watching for it. 



Although excrement is always to be met witli on rookeries and hauling grounds," 

 it is by no means commensurate with the number of seals, while Mr. Clark in Septem- 

 ber and October noticed large quantities of fecal matter strewn along the shore in 

 localities where the pups were sporting in the water. 



Bones of fishes or remains of squids are also very seldom found on land on the 

 Pribilofs, indicating that these, too, are rejected in the water, while they are much more 

 common on the Commander Islands where the feeding grounds are not so far from the 

 rookeries as on the American Islands. 



Although we know little of the food of the fur seal south of the Aleutian Islands, 

 something may be inferred from the character of its food in Bering Sea. Since the 

 seal feeds near the surface, none of the bottom-haunting flishes such as the cod and 

 halibut, nor their enemies, can be influenced by it, except so far as their food supply 

 may be affected by the destruction of pollock, and it is highly improbable that the 

 cod fishery of Bering Sea could have been in any way affected by the fur seal. Sur- 

 face-swimming species, like the salmon, might possibly be destroyed in appreciable 

 numbers were the fur seal abundant, but as no previous effect has been reported, 

 although it is fair to say that no study of the subject was made in the past, the verdict 

 for the present must be — not proven. 



In regard to the bearing of the seals upon fisheries. Dr. Stejneger's remarks con- 

 cerning Bering Island are very much to the point. He says:^ 



Three species of salmon {Oncorhynchus) abound in all the rivers on Bering Island and the fur 

 seals are not observed to feed upon them at the mouths of these rivers; but the fact that the 

 largest salmon river of the island, the Saranna River, is situated less than 7 miles from the largest 

 rookery, without the seals coming over there to feed upon the enormous number of salmon ascendin" 

 that river, is proof conclusive. * * » The annual catch in that river alone varies between 20 000 

 and 100,000 salmon. ' 



As for the codfish, it is only necessary to state that they are common right off the great North 

 Rookery of Bering Island. On September 16, 1895, we were anchored in 10 fathoms of water, loss than 

 a mile from Sivntchi Kamen, and within hearing of the roar from the rookery. A single cod line over 

 the side of the steamer for a couple of hours brought np three-fourths of a barrel of codfish. 



1 That, as has been stated, anyone ever searched for excrement and did not find it indicates very 

 poor powers of observation or of veracity. 



2 The Russian Fur Seal Islands, p. 70. 



