OTHER MIGRATORY BIRDS 



Migratory birds other tli;iii waterfowl include 

 such game species as doves and pigeons, woodcock 

 and snipe, and rails. They also encompass diverse 

 groups of nongame water and land birds, from 

 the endangered whooping cranes to the diminutive 

 songbirds. All are protected under international 

 treaties with Great Britain (for Canada) and 

 Mexico. The Bureau is the responsible agency 

 for the United States under these treaties. 



Dove-icing collection surrey. — Since the annual 

 mourning dove census provides only an index to 

 the breeding population, production success must 

 be ascertained by other means. It lias been deter- 

 mined that age ratios may be obtained in the early 

 fall from wing examination. In oi-der to appraise 

 the feasibility of I'ountrywide dove-wing collec- 

 tion, pilot collections were nuide in Maryland and 

 Arizona during September 1964. 



In Maryland, 3,499 wings were collected by Bu- 

 reau and Maryland Game and Inland Fish Com- 

 mission personnel. Of these, 2,800 were classed 

 as immature, 503 as adult, 184 as unknown because 

 of having completed the molt, and 12 unknown 

 because of wing damage. Based on usal)l(' wings, 

 the young: adult ratio was 5.56:1, or about tlie 

 same as in 1963. Band recovery rates indicate tliat 

 immature doves are about 1.5 times as likely to be 

 shot as adults, whicli means that the age ratio 

 in the preseason popidation was 3.7: 1, or 79 per- 

 cent young. 



The dove-wing collection in .Vrizona was under- 

 taken in cooperation with the Arizona (Jame and 

 Fish De]iartment. Wing en\elopes were sent 

 from the Migratory Bird Populations ."Station to 

 2,356 Arizona sport.smen selected at raiulum from 



a list of white-winged and mourning dove hunters. 

 A total of 992 respondents returned 3,170 envel- 

 opes and 22,362 dove wings, averaging 5.4 white- 

 wings and 7.7 mourning doves, or 7 wings per 

 hunter response. The age ratio for white-winged 

 doves was 1.77 : 1, and for mourning doves, 0.79 : 1. 

 Reasons for the large disparity in age ratios be- 

 tween Maryland and Arizona are being studied. 



Minimum hreeding age of m-ourning daves. — 

 Little evidence has been gathered in the past on 

 the mininmm breeding age of mourning doves. 

 Since young are hatched as early as January and 

 February in southern Arizona, many birds have 

 the external appearance of adults by midsummer, 

 and whether they are se.xually mature has long 

 Ijeen a question. Evidence that birds of the year 

 are able to breed was gathered on two study areas 

 in the vicinity of Tucson, Ariz. Actual rejiring 

 of young by this age gi'oup was documented, 

 and corroborating evidence on various stages of 

 the breeding cycle was also collected. 



Woodcock productivity. — A selected sample of 

 wfx)dcock hiuiters in the United States and Can- 

 ada sent to the Migratory Bird Populations Sta- 

 tion 12,826 wings from birds shot in 1963. Age 

 and sex of the birds were determined by differ- 

 ences in pattern and color of the flight feathers, 

 limiting dates in 1903 varied considerably from 

 those in 1962 because of season closures brought 

 on by drought conditions. Accordingly, the wings 

 were not gathered under coini)aral)le conditions. 

 Nevertheless, a comparison of the number of 

 young per adult female suggested no change in 

 productivity from 1962 to 1963. This conclusion 

 is supported by the singing-gi'ound survey which 



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