BUREAU OF BIOLOGICAL SURVEY. 265 



diicecl in numbers by draft and enlistment. Analyses were completed 

 for the siskin, pipits, longspurs, and red-eyed vireo, and miscella- 

 neous examinations made for a considerable variety of other birds. 

 Publications issued during the year, in addition to that on the 

 crow, were a Department Bulletin, "Food Habits of the Swallows, 

 a Family of Valuable Native Birds," and Farmers' Bulletins, " How 

 to Attract Birds in the Middle Atlantic States," and " How to Attract 

 Birds in the East Central States." Five Farmers' Bulletins were 

 revised during the year. 



BIOLOGICAL INVESTIGATIONS. 



Biological investigations have been conducted during the year, 

 both in field and in laboratory, along lines essential to the administra- 

 tion of the Bureau. The correlated activities which depend to a 

 greater or less extent on these investigations include the administra- 

 tion of the Federal migratory bird law ; the enforcement of the Lacey 

 Act, which regulates importations of, and interstate commerce in, 

 birds and mammals; the maintenance of mammal and bird reserva- 

 tions; the economic relations of birds and mammals to agriculture, 

 stock raising, forestry, and the conservation of game. 



Large additions have been made to the card indexes of data con- 

 cerning the distribution, abundance, and habits of the various species 

 of North American birds and mammals, including unpublished data 

 gathered by field parties of the Bureau and miscellaneous manuscript 

 records from outside sources, as well as a vast amount of information 

 gathered from publications. 



DISTRIBUTION AND MIGRATION OF BIRDS. 



Reports on the migration of birds have been received from nearly 

 400 volunteer observers located throughout the United States and 

 many parts of Canada and Alaska. Much additional information 

 concerning the distribution and migration of birds was gathered from 

 published sources. Indexed files containing these data consist of con- 

 siderably more than a million cards. These files are of fundamental 

 importance in connection with the administration of the Federal 

 migratory bird law. 



BIRD COUNTS. 



Reports of the fourth annual series of local counts of breeding 

 birds made in various parts of the United States were received from 

 about 135 observers, many of whom reported on more than one area, 

 bringing the total number of counts of nesting birds on selected areas 

 to about 200. These schedules include many counts made on areas 

 previously covered, afi'ording opportunity for comparing conditions 

 on the same area during succeeding years. In many cases a gratify- 

 ing increase in bird population has been observed. Effort is being 

 made to enlarge the list of volunteer observers and especially to se- 

 cure reports from areas representative of the various physiographic 

 types throughout the country. 



BIOLOGICAL SURVEYS. 



Field work continuing the biological surveys of States was con- 

 ducted in Arizona, Florida, Montana, Washington, and Wisconsin, 

 substantial progress being made in all these States. A report on the 



97335°— ABG 1918 18 



