LIFE HISTORIES OF NOETH AMERICAN PETRELS AND PELICANS. 261 



Lakes) to western Nevada (Pyramid Lake) and southern California 

 (Salton Sea) . On islands off the coast from northern Oregon (Three 

 Arch Rocks) southward along the coasts of California and Lower 

 California to the Revillagigedo Islands. The breeding birds of Great 

 Salt Lake may be intermediate between this and the eastern form. 

 Breeding grounds protected in the following reservations: In Oregon, 

 Three Arch Rocks, Klamath Lake, and Malheur Lake ; and in Cali- 

 fornia, Farallon. 



Winter range. — Includes most of the breeding range, except per- 

 haps the more northern inland resorts, and extends to the valley of 

 the Colorado River and the Gulf of California. 



Egg dates. — Farallon Islands : Twenty-seven records, May 9 to July 

 12; fourteen records. May 30 to June 28. Los Coronados Islands: 

 Eighteen records, March 27 to June 3 ; nine records, April 3 to May 

 10. Oregon, California, and Nevada : Twelve records, February 5 to 

 June 6; six records, April 20 to May 20. 



PHALACROCORAX VIGUA MEXICANUS (Brandt). 

 MEXICAN CORMORANT. 



HABITS. 



This small, but handsome-, cormorant is a tropical species which 

 extends its range northward over the Mexican border and into the 

 southern part of the Mississippi valley. It has also been found 

 breeding in some of the West Indes. It is the only one of the North 

 American species of cormorants that I have not seen in life. Com- 

 paratively few ornithologists have studied its habits and still fewer 

 have published anything about it, so its life history will be rather 

 meager. It seems to be rare north of Texas and Louisiana, but on 

 the coasts of southern Texas and Mexico it is a common bird of the 

 salt water lagoons, rivers, and inland lakes, much resembling in ap- 

 pearance and behavior the well known Florida cormorant. 



Nesti7ig. — It is apparently not a migratory species, being a resi- 

 dent throughout the year over practically all of its range and hav- 

 ing a much extended breeding season. Dr. E. W. Nelson (1903) has 

 given us the best account of its habits and I shall quote freely from 

 his notes. On Christmas day, 1902, he discovered a breeding colony 

 of Mexican cormorants on Lake Chapala, Mexico, of which he 

 writes : 



In tlie afternoon a long line of whitened bushes growing in the open water 

 some distance aw^ay was pointed out by our host who said he liad passed there 

 a short time befoi'e and found a lot of cormorants nesting in them. I could 

 scarcely credit this but the whitened appearance of the buslies showed that the 

 birds used the place as a roost at least and I decided to investigate. As w'e 

 poled near enough we saw that the bushes, or small trees, which projected 

 twelve or fifteen feet from the water were full of cormorants and many could 

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