154 



Bird - Lore 



In studying the home-life of the Warblers, one is continually being im- 

 pressed by the great individual differences in the habits of each species. When 

 one is about ready to make a generalization, for example that the male Yellow- 

 throat never assists in incubation or care of the young, the very next pair that 

 one watches may reverse the tables and the male may do most of the work. 

 In general, however, the cycle seems to me to be as follows: the resident 

 individuals arrive after a certain number of migrating individuals have 

 passed through. The resident males arrive sometime before the migrating 

 females and several days, or even weeks, before the resident females. Each 

 male selects a circumscribed nesting-area where he permits of no intrusion 

 by other males of his species. Here he sings and displays and awaits the 



A SWAMP-LOVING FAMILY 

 The (Northern) Water Thrush requires extreme humidity, pools of standing water, moss, and ferns 



coming of a female that will be susceptible to his charms and that will 

 approve his choice of a nesting-area. Very often it is the same female that 

 accepted him the } ear before, because the homing instinct is just as strong 

 in her as in the male, and she will ordinarily return to the spot where she 

 nested the year before. If her former mate is still strong enough and aggres- 

 sive enough to drive off other males, she re-accepts him. Otherwise she 

 accepts, with equal grace, his conqueror. The female selects the actual nest- 

 ing-site and ordinarily builds the nest, though the male often pretends to help 

 and is occasionally quite assiduous in his assistance. In the case of the Pro- 

 thonotary Warbler, already mentioned, the male built an entire nest while 

 waiting for a female to put in an appearance. 



In the majority of cases the female performs all the duties of incubation, 



