SOMETHING ABOUT BIRDS [9] 



observer who watches from one of these blinds soon learns that each adult 

 has built up a stereotyped behavior. It habitually forages in the same 

 area and comes to and leaves the nest by the same route, even alighting 

 on the same twigs each time. In some individuals, this response becomes 

 almost automatic and very firmly fixed. Gabrielson, in preparing to watch 

 a House Wren, inadvertently placed his blind across the out-bound path 

 of one of the parents. This disconcerted the bird for a time and resulted 

 in a lot of scolding. It eventually solved the problem, not by changing 

 its route, but by varying the steps. From the nest it flew directly to the 

 opening of the blind, lit on the cloth in the opening, hopped from that 

 to the observer's knee, then onto his shoulder, and out through the 

 entrance opening on the opposite side of the tent. After this routine was 

 established, the bird became reconciled to the tent and made the trips 

 through it in the fashion indicated many times that day. 



MIGRATION 



FROM THE early dawn of history, the migratory movements of birds have 

 excited curiosity and speculation among the peoples of the world. This 

 interest has resulted in the development of curious legends and beliefs, 

 some of which still persist strongly in many countries. For example, at 

 one time it was widely accepted that when all the clan of swallows and 

 swifts that gathered in the large autumnal companies that are such 

 familiar late-summer sights over the marshlands were assembled, all the 

 birds took wing at once, dived into the water, swam to the bottom and 

 buried themselves in the mud, to emerge the following spring after the 

 cold weather had passed. In other lands, barnacles were supposed to 

 change into geese, and fruits or seeds of certain trees that grew along the 

 seashore and dropped into the water were supposed, by some mysterious 

 alchemy of the deep, to be transformed into waterfowl of various types. 



STUDY OF MIGRATION ROUTES 



IN MODERN times, with modern facilities of travel and methods of com- 

 munication, bird migrations are much better understood, and we now 

 know in a great measure the summer and winter homes of our common 

 birds and the routes traveled. The first systematic study of migrations 

 of North American birds on a large scale was undertaken by the Biological 

 Survey and was carried on for many years by Professor Wells W. Cooke. 

 By using hundreds of volunteers, acquainted at least with the common 

 birds scattered over the United States, and getting these observers to 

 record the first spring and fall appearances of the birds and other data, 

 he soon began to accumulate an immense volume of information. True, 

 there were probably many individual errors of observation and identifi- 



