A Co-operative Study of Bird Migration 



25 



At the first post-nuptial (second fall) molt, the pink plumage of the adult 

 (Fig. 5) is gained. For the first year of its life, therefore, the male Purple 

 Finch resembles the female in color, but, having once assumed the pink plumage 

 of maturity, it is thereafter retained, and the only further change in color is 

 due to the wearing off of the whitish barbules of the reddish feathers, which, 

 as Dr. Dwight has shown ('Sequence of Molts and Plumages', Ann. N. Y. Acad. 

 Sci., 1900, 173), makes the adult male appear to be brighter in summer than 

 at other times. 



The California Purple Finch (Carpodacus purpureus calif ornicus), of 

 the Pacific Coast Region, closely resembles the eastern bird, but the male is 

 duller and darker, the female more olive-green above. As is well known, caged 

 male Purple Finches lose their pink plumage and become and remain saffron 

 in color, a phenomenon which is generally ascribed to the effects of change of 

 food. 



A Cooperative Study of Bird Migration 



Bird-Lore asks the coiiperation of its readers in recording the migrations of 

 certain common birds in the belief that a joint study of their movements will add to 

 the interest with which their coming is awaited, and contribute something of 

 value to our knowledge of their travels in particular, and bird migration in general. 



By restricting the plan to a small number of common and well-known birds, we 

 largely avoid the danger of misidentification, focus our efforts and thereby increase 

 the value of the records contributed. 



It is proposed to take three birds which arrive during the earlier part of the 

 migration season, and three more which are due in the latter part. A summary 

 of observations on the first group will be published in Bird-Lore for June, while 

 those relating to the second group, the names of which will be announced later, 

 will appear in Bird-Lore for August. 



The first three birds selected are the Redwinged Blackbird, Robin, and 

 Phoebe. A blank form is appended showing how the records should be scheduled 

 before sending them to Bird-Lore. These records should be mailed to Mr. Charles 

 H. Rogers, care of Bird-Lore, American Museum of Natural History, New York 

 City, not later than April 10. — F. M. C. 



Report from. 



(Give locality) 



Made by. 



(Give 



name and address of observer) 









Date 

 first seen 



No. 

 seen 



Date 

 next seen 



No. 

 seen 



Date of 

 becoming 

 common 



Red-winged blackbird 











Robin .... 













Phoebe . . . 













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