856 U.S. NATIONAL MUSEUM BULLETIN 23 7 part 2 



birds of the year can be distinguished from adults only by a faint tan 

 remainder of the juvenal chest band. 



Adults undergo a complete postnuptial molt which starts in August 

 and may continue into October. During this period many tailless 

 birds are in evidence. One adult captured August 24 had the first 

 five primaries new, and new primary coverts only over the new pri- 

 maries. The fresh feathers are darker and longer than the old ones. 

 I have seen no evidence of any molt in winter or spring. The white 

 and buffy edges of the contour feathers wear off during the winter 

 to produce the very dark nuptial dress. 



Food. — Howell (1932) states: "Six stomachs of birds of this species 

 were examined * * *. The food contents consisted largely of insects 

 and spiders, with some vegetable matter. Grasshoppers and crickets 

 composed about 37 percent of the total, and spiders about 25 per- 

 cent. Other items were beetles, bugs, horse flies, dragon flies, 

 lepidopterous larvae, Hymenoptera, and a praying mantis. The 

 vegetable matter consisted of a few seeds of sedges, one seed of wax 

 myrtle, and a quantity of tubers of a grass or sedge." 



In addition I have seen them feeding on small snails and possibly 

 ants. I saw one female carrying a dragonfly larva and another an 

 adult salt marsh butterfly to their nestings. Except for a few red- 

 winged blackbirds, the salt marshes do not harbor many other insecti- 

 vorous birds, and the seaside sparrows have little competition for 

 their food. 



Behavior. — During the nonbreeding season the duskies are quite 

 shy, and either remain concealed in the dense vegetation or fly long 

 before one comes near. In the breeding season they become rather 

 tame. Parents with heavily incubated eggs or young in the nest 

 are very bold and will come to within 15 or 20 feet of an intruder at 

 the nest. They perch on the grass tops and nervously twitch their 

 tail and wings, bob up and down, and scold continuously with their 

 metallic chip-chip, chip-chip until you leave. For a week or so after 

 the young leave the nest the female will come almost within arm's 

 reach and chip incessantly whUe trying to lead you away. 



After a shower the wet males often sit exposed on the top of the 

 vegetation to fluff and preen their feathers. I watched one such male 

 scratch his head three times, twice over and once under the wing, after 

 which he stretched the same wing out over the extended foot, down- 

 ward and behind the body. 



Voice. — The dusky male usually gives his territorial song from an 

 exposed perch with his head thrown back, bill open, and neck visibly 

 vibrating. Typically the song has one or two short introductory 

 syllables which do not carry far, followed by a longer buzzing note, 

 which Nicholson (MS.) writes toodle-raeeeee. Peterson (1947) calls 



