1476 U.S. NATIONAL MUSEUM BULLETIN 23 7 part 3 



apparently takes no interest in their whereabouts and sits quietly down, curiosity 

 may overcome their suspicions and bring them into view. 



Spring. — The "swamp song sparrows" are first heard in the breeding 

 range in March, and they reach a numerical peak in New England in 

 mid-May. At this time they can be found in many swamps where 

 there will be none during the nesting season. The sparse northern 

 wintering population is probably migratory; a bird banded at Athol, 

 Mass. in January remained at the banding station until April when it 

 disappeared (Bagg and Eliot, 1937). One banded at Lisle, 111., 

 May 1, 1931, was found dead a year and a day later in Clarion, Mich. 



P. L. Hatch (1892) states, perhaps without critical evidence, that 

 the females arrive a few days later than the males in spring. 



LeRoy C. Stegeman (1955) notes that swamp sparrows are lighter 

 in weight in the spring than they are in the fall. This condition, the 

 reverse of that in its near relative, the song sparrow, he attributes to 

 the fact that the swamp sparrow is more insectivorous and less 

 granivorous than the song sparrow. 



Nesting. — The swamp sparrow breeds in fresh water marshes, 

 swamps, bogs, and wet meadows, and about the low swampy shores of 

 lakes and streams, more rarely in coastal brackish meadows. Usually 

 only a few pairs occupy a given locality, but occasionally it seems 

 to nest semi-colonially where conditions are suitable. Chandler S. 

 Robbins (1949) reports a breeding density of 21 per 100 acres (2 in 

 9% acres) of "open hemlock-spruce bog" in Maryland. J. W. Aldrich 

 (1943) determined that in northeastern Ohio it shares seasonal 

 predominance with the redwinged blackbird and Virginia rail in the 

 Decodon-Typha Associes; with the short-billed marsh wren, redwinged 

 blackbird, and Virginia rail in the Juncus-Scirpus Associes; with the 

 song sparrow, yellowthroat, and yellow warbler in the Nemopanihus- 

 Alnus Associes; with the song sparrow, American goldfinch, robin, 

 yellow warbler, yellowthroat, redwinged blackbird, kingbird, and 

 Traill's flycatcher in the Cephalanthus-Alnus associes; and with the 

 song sparrow and yellowthroat in the Chamaedaphne-calyculata 

 Consocies. G. M. Allen (1925) states more simply that in most 

 New England swamps "The Swamp Sparrows are found in the inner 

 grassy ring; Song Sparrows and Yellowthroats in the bushy border." 

 George M. Sutton writes me that he believes, from observations at 

 the George Reserve in Michigan that this species requires mixed 

 vegetation, a more complete overhead shelter than a pure stand of 

 Chamaedaphne affords, and that adequate nest-sites are not provided 

 by a pure stand of cat-tails. 



Practically nothing is known of territorial behavior in this species, 

 nor has its courtship been described. The male generally sings from 

 a conspicuous position on an alder or willow or cat-tail, and often 



