^ Ol l906 in ] Anthony, The Large-billed Sparrow. 149 



WHERE DOES THE LARGE-BILLED SPARROW 

 SPEND THE SUMMER? 



BY A. W. ANTHONY. 



In the January issue of 'The Auk/ 1905, Mr. Joseph Grinnell 

 has given us some interesting notes on the Large-billed Sparrow 

 (Passerculus rortratus), and called attention to the fact that this 

 species, which is in winter abundant all along the coast of southern 

 California and the northern half of Lower California, has until 

 the present time succeeded in keeping its breeding ground so well 

 hidden that with all of the dozens of trained collectors that have 

 studied the species on its range, none seem to be able to state where 

 it nests. 



It is no doubt true that there has been no authentic record of eggs 

 found or nests taken, but the region is so well known both north 

 and south of the winter home of the Large-billed Sparrow, and the 

 local lists for the coast from San Francisco south are so complete, 

 that I think we can locate the summer and breeding range of this 

 species within fairly definite limits and with reasonable accuracy. 

 I think that perhaps the shortest route to the probable nesting 

 grounds will be by a process of elimination of some of those sec- 

 tions where it does not nest. 



So far the most northern record for the species is Santa Cruz, 

 nor is it at all common north of Point Conception, I think. If the 

 nesting ground were to be sought for in the north, certainly some of 

 the many collectors in the region of San Francisco would have 

 reported migrating birds, and as none have been recorded, we may 

 for the moment consider the coast region of the north as out of the 

 nesting habitat. 



As for the winter range, anyone who has collected in the tide 

 flats about San Diego Bay can testify that here at least they swarm 

 until March 5 or later. Such cover would seem to best suit the 

 requirements of the species, for I have found them equally abundant 

 in all similar localities south of San Diego, notably San Quintin, 

 Lower California, and Todas Santos Bay, south of Ensenada. 



That there is a regular migration is attested by their appearance 



