BUREAU OF BIOLOGICAL, SURVEY. 441 



DISTRIBUTION AND MIGRATION OF BIRDS. 



Bird migration reports were received from about 285 volunteer 

 observers ; a number of these have been sending in records from the 

 same localities for more than 20 years, and a few as long as 30 years. 

 The cumulative value of such series of records can scarcely be esti- 

 mated. The card catalogue of the bird collection was brought up to 

 date, and considerable work was done in rearranging the study 

 collection of birds. 



BIRD CENSUSES. 



Reports on the birds breeding on definite areas, usually selected 

 as affording a variety of topographic conditions and different types 

 of vegetative cover, numbered about 100, nearly double the number 

 received during the previous year. Many of these involved areas 

 which had been reported on during several previous years, thus 

 affording an index to such local fluctuations in bird life as may have 

 occurred. A publication on this subject, the third report on bird 

 censuses in the United States, covering the period from 1916 to 1920, 

 inclusive, was in press at the close of the year. 



BIRD BANDING. 



The work of banding birds, as an aid to the study of distribution 

 and migration, made material progress during the year. More than 

 25,000 birds were banded and the number of cooperators increased 

 to 851, of whom 63 are in Canada. During the shooting season 668 

 returns of banded ducks were reported, which has added much to 

 our knowledge of the seasonal movements of these important species. 

 There has been a gratifying increase in the number of persons under- 

 taking the operation of trapping stations, by means of which the 

 best returns of the small nongame birds are obtained, and the results 

 have been correspondingly satisfactory. 



In October the Inland Bird Banding Association, formed to coor- 

 dinate the activities of cooperators of the bureau in the Mississippi 

 Valley, was organized in Chicago, the work of this organization 

 being in a measure similar to that of the New England Bird Banding 

 Association, which was formed in 1921. Plans have been formulated 

 looking to the organization of similar regional associations covering 

 the Atlantic seaboard and the Pacific slope. 



An important feature of the year's progress has been the perfect- 

 ing by a private firm of machinery which makes it possible to manu- 

 facture numbered aluminum bird bands cheaply and in large quanti- 

 ties, thus solving what has heretofore been a perplexing problem. 



During the year two important field trips were made by an assist- 

 ant for the purpose of banding ducks. The first expedition, covering 

 most of October and November, involved trapping and banding 

 ducks on an extensive scale on the grounds of the Sanganois Club, 

 near Browning, 111., where similar work had been done during the 

 early spring of the same year. By means of traps of wire netting 

 it was possible to capture and band over 1,300 ducks, including mal- 

 lards, black ducks, and pintails. It is expected that many interesting 

 returns will be reported during the fall shooting season. Another 

 trip was made in January to Oakley, S. C, for the purpose of exam- 

 ining a proposed station for trapping and banding ducks. The con- 



