354 BULLETIN 195, UNITED STATES NATIONAL MUSEUM 



they had become mated. The nest was soon finished and the eggs laid. 

 During the period of incubation, I heard the male thrasher sing a few 

 notes one day, but that was all the song I heard from the bird that 

 summer. They produced a brood of young successfully. 



"I believe that both the brown thrasher and the catbird are terri- 

 torial in nesting behavior. But in this region the catbird is extremely 

 abundant and the thrasher only fairly common. For catbirds terri- 

 tory is scarce, but for thrashers it is abundant. Evidently a pair of 

 thrashers can have their pick of territory, once they are mated, by 

 simply taking that of the catbirds. So they often move elsewhere 

 after the mate arrives, whereas catbirds must stick to the territory 

 they have selected. 



"So, it seems from this observation that the male thrasher does not 

 always select the nesting territory, but merely one to which it first 

 attracts a mate by its singing. The nesting territory, in some cases at 

 least, is selected after the mating has taken place, and then it would 

 seem likely that the female would have more to do with the selection 

 than her mate." 



From Dr. Erwin's (1935) studies of the territorial behavior of the 

 brown thrasher on Peabody College campus, "it seems that the male 

 Thrasher selects a desirable area immediately after arrival, and re- 

 mains in this area for 10 or more days before beginning his song. The 

 author was unable to secure data which would indicate whether terri- 

 torial fights occurred within this interval or not." He continues : 



An effort was made to locate the boundaries of the territories of each pair of 

 Thrashers on Peabody Campus. The method used was the observation of the 

 limits of their feeding grounds and the locations and results of territorial fights. 

 * * * There seemed to be a definite tendency for the Thrashers to adopt 

 buildings, driveways, walks, and shrubbery rows for boundaries in many cases. 

 After a territory was established, the activities of the particular pair of Thrash- 

 ers seemed to be almost entirely confined to this area. All nests of the season 

 were built within this territoi'y. * * * 



Thrashers almost always object to the presence of other Thrashers in their 

 territory, although they usually do not object to the presence of birds of other 

 species so long as they do not go near their nest, or do not interfere with their 

 feeding activities. 



Courtship. — The loud, tree-top song of the male is the first step in 

 the courtship performance, the curtain raiser, as it were. It will be 

 noted from the above account that the male does not begin to sing 

 immediately on his arrival but waits until he can expect the arrival 

 of a possible mate, a matter of perhaps 10 days or 2 weeks. Then he 

 issues his loud invitation, which, under favorable circumstances, may 

 be heard at a long distance. This song is also a challenge to rival 

 males, and territorial fights between the rivals may occur during the 

 early stages of courtship. When the male and the female finally come 

 together, the song of the male becomes so subdued and soft that it is 



