craft. Many appi'oaches are being used by the 

 Branch in developing such measures: cultural 

 practices, including the encouragement of agricul- 

 tural experiment stations in the development of 

 damage-resistant crops; manipulation of habitat; 

 chemical repellents and scaring devices; drugs and 

 lethal substances; sonic and electronic installa- 

 tions; traps; radiation; reproductive inhibitors; 

 and disease organisms, to give a partial list. 



Blackbirds. — During the last 2 years 252 winter 

 roost sites, holding an estimated 214 million black- 

 birds and starlings, were located in the United 

 States. The search is continuing and at this time 

 it is not known what portion of the countrywide 

 population is represented by these millions of 

 birds. The buildup of starlings in the West has 

 continued, and concentrations in some California 

 feedlots have become a matter of real concern. 

 About 1 million blackbii'ds and starlings have been 

 banded— 38,700 in 1962— as part of the effort, to 

 obtain basic information on migrations, seasonal 

 movements, and concentration areas, knowledge 

 of wliicli facilitates control. 



Red-winged blackbird feeding on corn. Because of 

 its wide distribution, great numbers, and fondness for 

 corn in all stage of kernel development, the redwing 

 is responsible for more damage to this crop than other 

 blackbirds. (Photo by Brooke Meanley) 



Blackbird and starling roosts, winter, 1962-63. An estimated 214,000,000 birds are represented in the 252 roosts 

 indicated. (Photo by Patuxent Wildlife Research Center) 



39 



