85 



period of such actions, the attitude of the male suddenly 

 changes. Instead of pursuing the female, he is more subdued 

 and takes to following her about. He never allows her to 

 escape from his sight, and as she hunts about near the water's 

 surface, he vaunts himself on the nearest cat-tail. They now 

 may be considered mated. At about this time (the last of 

 April), although there are comparatively few birds in the 

 marsh, the migration ceases for a time. The flocks which 

 come in each night and leave each morning are scattering, and 

 are composed entirely of resident birds. Before all of the 

 birds have become mated, the females naturally predominate 

 in the flights to and from the uplands, for the still unmated, 

 resident males spend the entire day in the marsh. After 

 mating occurs, and before and during the building of the nest 

 and oviposition, the sexes leave together for the hills in the 

 late morning, and return in the late afternoon. A study of the 

 food at this season of the year, without reference to sex or 

 time of day or place of collection, would therefore give most 

 varied results. The vegetation in the marsh is beginning to 

 show considerable green above the water. The cat-tails are 

 about thirty inches in height, the burreed is well started, the 

 water horsetail and the sweet flag are eight or ten inches in 

 length, though not yet showing above the water's surface, 

 and the sedges have sent up sprouts about two inches in length. 

 Stretches of open water mark burned-over areas that will soon 

 be covered with a new and luxuriant growth of sedges. In- 

 sects at this period appear in greater numbers and supply 

 abundant food for the Redwings. Numerous tabanid and 

 other dipterous larvae are floating at the surface of the water, 

 and furnish the almost exclusive food of some individuals. 

 Other individuals continue their diet of lepidopterous larvae and 

 weevils, adding only the spiders, whose wind-blown webs some- 

 times fairly cover the cat-tails (Plate XVIII, fig. 3). But the 

 migration has not yet ceased. 



Arrival of resident immature males. — About the first week in 

 May, after most of the adult resident birds have begun to 

 nest, the immature residents begin to appear in numbers. 

 The days are much longer now, and the sun does not sink below 



