SOUTHERN SWAMP SPARROW 1479 



Nothing has been written of nest sanitation, which probably does not 

 differ from that in the song sparrow. G. M. Sutton writes me that 

 he found bits of shell in a nest after the young had fledged, suggesting 

 that the shells may sometimes be crushed rather than carried away by 

 one of the adults. 



The chicks hatch with their eyes closed and are very helpless. 

 They make no sound as they gape for food. The inside of the mouth 

 is pink with a very pale yellowish border. The pinkish skin is so 

 transparent the viscera and blood vessels show clearly through the 

 abdomen wall. The tiny egg tooth is about 1 millimeter from the 

 tip of the bill. The upper mandible is pigmented sooty gray ante- 

 riorly; the toenails are horn color. The flight feather tracts show 

 pigmentation where the feathers will appear. As the young grow 

 older their mouth lining becomes much brighter orange with a yellow 

 border than in the newly-hatched fledglings. 



E. H. Forbush (1929) states: 



The young ordinarily remain in the nest about 12 or 13 days, if undisturbed. 

 Swamp Sparrows nest near water so frequently that the callow young in their 

 first attempts at flight are likely to fall into it and struggling as they do on the 

 surface, they sometimes fall a prey to large frogs, fish or turtles. The following 

 from one of my note books shows how one little bird bravely struggled to safety: 

 Concord, August 28, 1907. This morning early as I stood on the river bank, a 

 bird flying toward me fell and struck the water about half way across the stream. 

 Immediately it fluttered swiftly along on the calm surface of the water for about a 

 rod, and then, apparently exhausted and unable to raise itself from the water, it 

 lay there for a few seconds, head under and tail a little raised. I looked to see 

 some fish seize it, but no! Suddenly by a vigorous struggle it raised its body 

 clear of the water and fluttered almost ashore, alighting on the pickerel weed at 

 the water's edge. A few minutes later, having regained its breath and courage, 

 it flew up into the bushes, and I saw that it was one of a brood of young Swamp 

 Sparrows in juvenal plumage, which were flitting along the shore. 



G. M. Sutton (1935) presumes that the young leave the nest "on 

 or about their ninth day." I have found them still in the nest on 

 the 7th day but gone on the 11th day. 



Plumages and molts. — The natal down is blackish brown. Seven 

 specimens had neossoptiles one-half inch long with the following 

 average distribution: coronal region 9, occipital 4, mid-dorsal 6, 

 upper pelvic 1, lower pelvic 6, femoral 8, scapular 5, greater secondary 

 coverts 7, ventral abdominal (these were white) 3. Sporadic pterylal 

 loci were the posterior orbital region, the distal middle secondary 

 coverts, and the proximal secondaries. 



To speak of a postnatal molt is a misnomer, as no passerine bird 

 actually "molts" its natal down. The loss of neossoptiles is by abra- 

 sion, a process which, although inevitable, is an accidental external 

 phenomenon of a different order than physiological molt. Some loss 



