504 PROCEEDINGS OF THE NATIONAL MVSEUM. vol. 56. 



noissance is necessary in order to ascertain what other animals are 

 after the fishes. With many opportunities for observation, I observed 

 the large birds feed from schools of fish that I knew to be pursued by 

 lobos only where the school was an immense one, and, therefore, 

 where there could be little to fear from the sea lion. 



There is yet another point of view from which some light may be 

 be gained. If the lobos are of especial value to the birds we might 

 expect to find ^ome direct relation between birds and lobos in their 

 distribution. Are the birds found in greatest abundance where the 

 lobos are most numerous ? 



At the islands of Lobos de Tierra there were observed considerable 

 numbers of birds, but not a large number of lobos, although one out- 

 lying island, occupied around its base by sea lions, was crowned with 

 a rookery of guanays. At Lobos de Afuera the birds were still more 

 numerous, especially pelicans, but sea lions were comparatively few. 

 Macabi Island was almost without birds, but was surrounded by 

 populous loberias. At Guanape there were a great many gannets, 

 but, at the time of my visit, few other birds. There were consid- 

 erable numbers of sea lions. In the Bay of Chimbote there were not 

 many birds, but an abundance of lobos. In the Chincha and Bal- 

 lestas Islands, the only island which had practically no nesting 

 ground was the middle island of the Chinchas, and this was the island 

 about which were found the greatest number of lobos. San Gallan 

 showed few birds, but some large loberias. In the region of the 

 Bahia de Independencia, with its islands of Vieja and Santa Rosa, 

 sea lions are very abundant, while birds are practically absent. Only 

 the small terrecle was abundant at Santa Rosa, and this is the kind 

 of bird that may derive much help from the lobos, because the}'' 

 barely strike the surface of the water as they take their fish, but 

 they produced little guano. 



In alm.ost every case the disappearance of the birds, or their 

 decrease in numbers, is largely due to the way they have been treated 

 by man, a,l though the sea lion may have formed a part of the unfav- 

 orable condition. For example, at such a place as the Santa Rosa 

 Islands, it is probable that the sea lions did not accomplish great 

 harm to the birds until the working of the islands began. Immature 

 birds that could fly from the land, but could not rise from the water, 

 into which they had been driven by man, would fall an easy pre}^ to 

 the sea lions. It is very natural that the birds would abandon those 

 points where they were pursued both on land and on the water, 

 sooner than those where their enemies vv^ere only on the land. 



The conclusions arrived at from all observations were: (1) That 

 the sea lion as a producer of guano was not of sufficient value to 

 require its protection; (2) that, as regards the relation between the 

 sea lions and the birds, the evidence did not indicate that the sea 



