NORTHERN SEASIDE SPARROW 829 



sharp-tail flies very much like the seaside, but can usually be recognized 

 by its smaller size and browner color. 



Enemies. — A Lavallette nest that contained four 3-day-old nestlings 

 on July 2 was empty when I checked it July 3, robbed by an unknown 

 predator. Both the common crow (Corvus brachyrhynchos) and the 

 fish crow (C. ossijragus) %nsited the marshes frequently as might be 

 suspected. A marsh hawk (Circus cyaneus) was also in residence 

 nearby, and whenever it appeared the sparrows disappeared quickly 

 and quietly into the grass. I watched it make many passes at what 

 I thought were sparrows, but I never saw it catch anything but 

 microtine rodents. 



The seaside sparrow has few natural enemies, for its salt marsh home 

 is comparatively free of the reptile and mammalian predators that 

 harass species inhabiting fresh marshes or upland fields. Perhaps the 

 few raccoons, skunks, or foxes that wander out on the marshes get an 

 occasional nest of eggs or young, and the bird-catching hawks must 

 take an unwary adult or two, but no evidence of either is recorded in 

 the literature. In listing the one known case of cowbird (Atolothrus 

 ater) parasitism on a seaside sparrow, Friedmann (1949) comments: 

 "The cowbird ordinarily does not penetrate brackish or salt water 

 marshes, and so probably rarely foists any of its eggs on the birds 

 that nest in such places. The seaside sparrow would appear, then, 

 to be an unusual, and rarely imposed upon victim." 



The worst threat to the seaside sparrow is the steady shrinking of 

 its habitat as the human population encroaches upon it and alters it. 

 Stone (1937) described how the "draining and 'development' of the 

 marshes" drove out all but a few pairs "of the thousands that once 

 nested about Cape May." He states "this species, the sharp-tail and 

 the Marsh Wrens are actually threatened with extinction so far at 

 least, as most of the New Jersey coast, is concerned." 



Fall and winter.— MieT the young have left the nest the adults 

 continue to feed them for approximately 20 daj^s. Young seaside 

 sparrows have a characteristic method of flying and dropping back into 

 the grass when they are flushed which makes them easy to recognize 

 as birds of the year. Stone (1937) saw a young bird still being fed 

 by an adult in Cape May County, N.J., on August 18, but remarks 

 that the date is very unusual and probably due to a delayed nesting. 

 At Lavallette all nesting duties were concluded early in August 1955, 

 and the birds were then beginning to form flocks. 



Cruickshank (1942) states that in the New York area "With the 

 first light frost in September a definite southward movement sets in. 

 It reaches a peak during the middle of October and is virtually con- 

 cluded by the middle of November. A number of birds regularly 



