Control methods that have sliown much promise 

 and wliic'h are now imdergoing further tests are 

 lethal baits and specially designed traps. Lethal 

 baits used in cattle feedlots resulted in the destruc- 

 tion of about 260,000 starlings in one Idaho in- 

 stance; and a method of using TEPP, an organo- 

 phosphate, for the control of feedlot-using birds 

 has been perfected and released for use under Bu- 

 reau supervision. In Delaware, Maryland, and 

 Virginia, nine decoy traps took 50,000 blackbirds 

 in one season, and a single trap took 20,000 birds 

 in a 35-week period. A total of 132,000 birds were 

 captured in light traps at five winter roosts in 

 1962. During the year, sterility-inducing chem- 

 icals were tested, and these materials show great 

 promise as control agents. Branch biologists are 

 working closely with agricultural interests in the 

 development of still more etfective control 

 methods. 



Birds and aircraft. — Birds were blamed for the 



loss of two aircraft in 1962. One was tlie crash 

 of an Air Force fighter plane on takeoff because 

 of engine failure due to ingestion of starlings, and 

 the other was the crash of a Viscount airliner after 

 colliding with two whistling swans. The Air 

 Force pilot escaped injury, but there were no sur- 

 vivors in the airliner crash. Tliese two accidents, 

 plus the 321 additional bird-plane strikes reported 

 in 1962, have emphasized the potential liazard of 

 birds to aviation and the need for continuing re- 

 search on the problem. Most of the strikes were 

 at altitudes of less than 2,500 feet, and engines 

 and wings were struck most often. Over 30 species 

 of birds were involved in the 323 collisions. The 

 Denver Center averted a bird hazard at the Staple- 

 ton Airport, Denver, by burning tlie cover pro- 

 vided by a small marsh a few hundred yards from 

 the main east-west runway where about 135,000 

 starlings and redwing blackbirds had established 

 a winter roost. 



Biologists examine ears of several varieties of corn in plantings exposed to blackbirds to determine ear characters 

 resistant to bird attack. (Photo by John T. Linehan) 



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