458 BULLETIN 20 3, UNITED STATES NATIONAL MUSEUM 



by April 27, Iowa by April 29, Minnesota by May 7, by mid-May they 

 are in Manitoba and Alberta, and by the end of May they are at their 

 outposts of range in Alaska. 



The ovenbird arrives on its breeding grounds in the spring with 

 great regularity, and there is much less variation in the date of arrival 

 from year to year than is exhibited by many other birds. It appears 

 at a certain point regardless of the weather, be it warm and summer- 

 like, freezing, or snowing. The coming of the ovenbird is so definitely 

 announced by its loud and easily recognized song that a factor in its 

 apparent punctuality may be its being promptly recorded. In my 

 own esperience I more frequently hear than see the first arrivals in 

 spring. 



Harry W. Hann (1937) has clearly established by banding and 

 careful detailed observation — 



that both male and female adult birds return to their old breeding grounds, if 

 possible. Old males have a good chance of obtaining their former territory 

 either by arriving early or by driving out the other males. Returning females 

 have more difficulty, however, since females probably return at more nearly the 

 same time, and there is the additional factor in their adjustment, with the 

 male. It seems obvious, though it was not actually observed, that the female 

 goes first to the old territory, and if the male there already has a mate, she 

 goes to an adjoining territory. The particular male in the territory seems to 

 be of no consequence. 



With both males and females attempting to return to the same place, there 

 would seem to be a strong tendency for the pairs to remate in subsequent years, 

 and this happened twice with banded birds. 



Courtship. — The courtship of the ovenbird, a most interesting and 

 remarkable affair, is intimately associated with the male's extraor- 

 dinary musical performance. One may see the birds walking casually 

 over the leaves of the forest floor, making scarcely a sound, then'i 

 through some sudden impulse the male starts after the female in a 

 frantic pursuit often terminated by a wild flight, during which he 

 pours forth a loud and eloquent love song. After this flight he returns 

 to the forest floor to sing his ringing "teacher" notes, Morris Gibbs 

 (1885) gives us an excellent account of this unusual courtship of a 

 pair of birds he observed near Grand Kapids, Mich. : 



Carefully crawling through the almost impenetrable growth of small saplings 

 and brush, I came at last to a partial clearing over which a bird, apparently 

 in the highest transports of joy, was fluttering in irregular flight. * * * i 

 observed another bird undoubtedly its mate, perched on the ground near, and 

 which appeared to be a Golden-crowned Thrush and the centre of attraction to 

 the delightful warbler overhead. Never had I heard the song before, and never 

 have I witnessed such a scene. This was indeed making love with a spirit which 

 I have never witnessed among our birds before. The song was almost con- 

 tinuous, and with an occasional interruption to the new song by the common 

 chattering notes so well known and described by Coues as a "harsh crescendo," 

 the notes were all of the most melodious description. The energetic uncon- 



