equipment detect minute quantities of pesticides in 

 soil, water, and animal tissue. Cunt ml methods 

 experts prescribe for mouse-infested orchards or 

 woodlands, seek repellents that prevenl forest 

 damage, or screen chemosterilants that may, w hen 

 perfected, prevent rodent and predator outbreaks. 

 The specialist in animal diseases is railed upon 

 when rabies in skunks or foxes reaches epidemic 

 proportions, or when birds are the suspected vec 

 tor in bacteria] contamination discovered in food 

 processed for human use. 



There are specialists in oilier disciplines used in 

 wildlife research. Available in Bureau programs, 

 or in cooperation with other agencies, are biologists 

 and biometricians skilled in measuring population 

 dynamics in game birds and mammals; ecologists 

 who devise methods of converting land marginal 

 for agricultural or industrial use into productive 

 and economically profitable wildlife habitat : and 

 aviculturists whose knowledge of animal behavior 

 appears to offer hope of preventing extinction of 

 the whooping crane and other threatened species. 



There are Bureau research specialists in other 

 wildlife fields. Their main and general assign 

 ment, in lx>th direct and cooperative investigations, 

 is the conservation of the Continent's migratory 

 bird resources, perpetuation of hunting and fishing 

 now inventoried at $8 billion annually, and preser- 

 vation and enhancement of outdoor recreational 

 opportunities of still greater value. 



RESEARCH OF SPECIAL NOTE 



Contamination by pesticides 



During the year, research biologists and analyti- 

 cal chemists of the Bureau collected and analyzed 

 hundreds of specimens of fishes, birds, mammals, 

 and food organisms. The findings revealed the 

 presence of pesticide residues in the eggs, tissues. 

 and vital organs of numerous species collected 

 from practically all parts of the country, including 

 several Canadian Provinces. For example, DDT 

 residues were present in 36 of 37 clutches of eggs 

 of wild black ducks taken in 8 States from Maine 

 to Maryland. In a number of cases the pesti 

 cidal levels in game species exceeded the tolerances 

 permitted in domestic meats shipped in interstate 

 commerce. The significance of almost universal 

 contamination of fish and wildlife by these chemi- 

 cals is yet to be determined. Since it is known 

 that minute amounts of some pesticides in the 

 daily diets of species such as quail and pheasants 



have pronounced effects upon their survival and 

 reproduction, man's widespread use of these chemi- 

 cals is regarded as one of the most serious threats 



faced by agencies charged with conservation of 

 living natural resources. 



New animal control methods 



I msiderable progress was made during the year 

 toward the discovery and development of new 

 and improved methods for controlling damage 

 caused by certain species of birds and mammals. 

 Foremost among these was the successful field test- 

 ing of a chemosterilant to limit reproduction of 

 coyotes over a 720-square-mile area in New Mexico. 

 Approximately BO percent fewer coyote pups were 

 produced on the treated area than on a comparable 

 check area. Advances were made also in the dis- 

 covery and development of selective lethal chemi- 

 cals with high toxicity to target species of birds 

 and mammals and comparatively low toxicity to 

 other kinds of wildlife. 



Bird banding 



With the installation of more versatile data- 

 processing equipment, methods of processing band- 

 ing data changed markedly in 1963. During the 

 year somewhat more than son, Dim birds were 

 banded, including 300,000 ducks, geese, and coots, 

 of which mallards totaled 10-2,841. Species of ma- 

 jor economic importance, mainly blackbirds and 

 starlings, accounted for about 200,000 records, and 

 gulls and terns for about 100,000. The good band- 

 ing year is further reflected by the .">0 percent in- 

 crease in the number of waterfowl banded, and 

 by the '21-percent increase in band recoveries. A 

 total of 2,329,931 bands were issued in 10(5.3, and 

 the attachment of preopened bands on plastic tub- 

 ing was begun. 



Visitors to the banding -tat ion came from 

 throughout the United States and Canada, and 

 from Europe and South America. 



Bat banding 



The importance of learning more about the dis- 

 tribution, migration, and life history of bats has 

 Keen under-cored during the past year by the ap- 

 parent increase in bat rabies, (irowth of the bat- 

 banding program during the year was spectacular, 

 as indicated by the following: Hands issued 254,- 

 925; records received, 19,500; recoveries reported, 

 1,201); total letters written (by the Bird Mammal 

 Laboratories). 635; and number of bats banded, 

 195,000 (approximately). 



