NORTHERN SEASIDE SPARROW 823 



normally single-brooded. The literature contains no information on 

 the duration of incubation, which I also was unable to ascertain 

 because I found no nest before it contained its full complement of eggs. 



The female seaside sparrow does all the incubating. While she is on 

 the nest the male usually remains a short distance away and sings 

 frequently from some favorite perch. When disturbed he gives alarm 

 notes that bring the female off the nest and both chip at the intruder. 

 When the female leaves for the feeding grounds before the eggs hatch, 

 the male accompanies her, and normally they return together. 



Young. — At hatching a crack develops around the widest part of the 

 egg where it has been etched on the inside by the egg tooth. Con- 

 traction of the chick's neck muscles separates the shell into two pieces, 

 and extending the legs frees the bird from the shell. Each of two 

 young I held in my hand during this process defecated in the shell 

 while freeing itself. When free of the shell the nestling rests on its 

 tarsi, abdomen, and forehead. The down dries in a few minutes, and 

 the skin becomes noticeably darker. 



The day they hatch the young start to gape, and as the parents feed 

 them their abdomens distend. During the first 24 hours they fre- 

 quently utter a soft "peep," and at its end are better able to right 

 themselves, and many feather papillae show distinctly through the 

 skin. On the second day the young are able to move short distances 

 by using their wings and feet. A thick ridge of tissue forms over the 

 eyeball where the eyelids later delaminate. The call now becomes a 

 double version of the "peep" note. When the young are 3 days old 

 the eyelids open slightly. During the next 3 days they become 

 better coordinated and their eyes open fully. The egg tooth is usually 

 lost by the sixth day. 



All incoming feathers remain sheathed until the seventh day, when 

 the body feathers start to emerge from the tips of their sheaths. Up 

 to this time disturbing the nest produced only a begging reaction. 

 Now they show the first signs of cowering and utter a squealing distress 

 call when handled. On the eighth day begging is less frequent, 

 cowering is the predominant attitude, and the young try to escape 

 when removed from the nest. The remigial sheaths now turn from 

 dark blue to gray and begin to slough off. 



The first young left the Lavallette nests, which it must be 

 remembered were being disturbed daily by my visits, on the ninth day, 

 and none remained in the nest beyond the tenth day. When I parted 

 the grass over a nest on the tenth day, the four young jumped out and 

 scattered in the grass. They were able to run well. One of them 

 gave a chipping note similar to the adult distress call. 



Both parents fed the young and maintained nest sanitation by 

 carrying fecal sacs away in their bills, I never saw an adult swallow 



