The Xantus Murrelet 



they will crawl under thick vegetation to lay, if their other requirements 



can there be met. 



The Xantus Murrelets have many nesting characteristics which are 



worthy of note, or 

 which, not fully under- 

 stood, have given rise to 

 many errors in bird 

 books. They are decid- 

 edly gregarious in their 

 breeding sites. For ex- 

 ample, on the Coronado 

 Islands, just below the 

 Mexican border, there 

 are three well defined 

 colonies on South Island. 

 Vet five miles away, on 

 North Island, which 

 swarms with Cassin 

 Auklets, gulls, pelicans, 

 and cormorants, no 

 Murrelet's nest has ever 

 been discovered. 



The individual 



birds of most species 



nesting in this manner 



will lay almost at the 



On any day in the late spring 



I have obtained 



Anacapa Island 



EGGS OF XANTUS MURRELET. IN SITU 



Photo by Dickey 



same time. Not so the Xantus Murrelet. 

 or early summer eggs exist in every state of incubation, 

 from the original data blanks of Mr. Nelson Carpenter, making due allow- 

 ance for condition, proof that in one of the colonies referred to on South 

 Island there have been eggs continuously from the earliest part of April 

 to the twentieth of July, — a period of over three and a half months. 

 On May first of this year (192 1 ) I examined nests containing a downy 

 young, sets of half incubated eggs, of fresh eggs, of eggs on the point of 

 pipping, besides numerous shells the conditions of whose membrane 

 showed that they had hatched this spring. 



This disposes of the theory of two distinct nesting seasons. These 

 birds are merely following individual idiosyncracies in their nesting dates. 

 They do not at any time congregate in flocks ; when found in groups larger 

 than three or four, it is merely a matter of accident. So when they come 

 to their breeding grounds, they do so independently of each other. The 

 result is violent fluctuations from year to year, and a season which, while 



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