8 BULLETIN 621, U. S. DEPARTMENT OP AGRICULTURE. 



them reported to contain over 100,000 birds. Here the open water 

 maintained by most of these streams throughout the winter and the 

 extensive tidal flats within easy reach of these rendezvous assure 

 the crows a fairly ample supply of food. In the Middle West a 

 greater region of favorable winter habitat has permitted the birds 

 to establish their roosts over a much broader area. As in the East, 

 the winter crows of the Mississippi Valley have selected a district well 

 supplied with their customary winter food. Here the roosts of 

 greatest size are found in southern Indiana, central Illinois, and 

 westward along the Missouri River, while eastern Kansas and north- 

 ern Oklahoma also support vast numbers. During fall and early 



Fig. 1. — Map showing location of crow roosts known to have been occupied in 

 the winter of 1911-12. 



spring the northern States from Maine west to the Plains harbor 

 many migrants, which form, at times, temporary roosts of consid- 

 erable size. From December to the middle of February, however, 

 the birds which frequent these States are comparatively few in 

 number and their roosts seldom contain over a few hundred indi- 

 viduals. The more important of these may be found along the coast 

 of Maine and in west-central New York, in the vicinity of Seneca 

 and Cayuga Lakes. In the South the largest colonies are found 

 along the Atlantic and Gulf coasts and are made up probably of 

 birds resident in the Southern States which have congregated at 

 favorable spots. Fish crows often form the bulk of the population 

 of southern roosts, and in fact are common in colonies as far north 

 as Maryland. On the Pacific coast, owing probably to the milder 

 winter climate, the roosts are found at higher latitudes, the coastal 

 region about Puget Sound being an area particularly well supplied. 



