298 



CALIFORNIA BIRD STUDIES 



dead stalks, on which the birds nest. Some contain many 

 acres, others less than an acre ; but large or small, all fur- 

 nish the essential requisite of insular isolation, and all 

 illustrate better than any other bird islands with which I am 

 familiar, the attraction of an island home for communal, 

 ground-nesting birds. 



" Low-lying snaky Cormorants " 



The White Pelicans find here no pebbles with which to 

 build their little mound-nests ; the Caspian Terns do with- 

 out sand; the Cormorants without rocks; all must nest 

 under exactly the same conditions; even the Great Blue 

 Herons, in default of trees, built their platform nests of 

 tules in the tules. 



I do not know how many islands were inhabited by birds, 

 but I counted fifteen on which Pelicans were nesting, and 

 there were at least a dozen more with Eing-billed and Cali- 

 fornia Gulls, Caspian Terns, Farallone Cormorants, and 

 Great Blue Herons. In most instances the birds nested near 

 the water and were therefore easily visible. 



Most of .the islands were separated by only narrow chan- 

 nels, the canals in this Venice of bird cities, through which 



