204 BIRDS OF PENNSYLVANIA. 



V. They do much harm by the distribution of seeds of poison ivy, poison sumach, 

 and perhaps other noxious plants. 



VI. They do much harm by the destruction of beneficial insects. 

 On the other hand 



VII. They do much good by the destruction of injurious insects. 



VIII. They are largely beneficial through their destruction of mice and other 

 rodents. 



IX. They are valuable occasionally as scavengers. 



The careful examination of large numbers of stomachs, and the critical study of 

 the insect food of the crow, may change materially the present aspect of the ques- 

 tion ; but so far as the facts at present known enable a judgment to be formed, the 

 harm which crows do appears to far outweigh the good. 



Corvus ossifragus WILSON. 



Fish Crow. 



DESCRIPTION. 



Smaller than C. americanus. Glossy black with green and violet reflections ; the 

 gloss of head, neck and belly greenish ; a small space at base of lower mandible, on 

 each side bare ? ; bill and feet black ; iris brown. Length 14 to 16 inches ; extent 

 about 32 inches. 



Habitat. Atlantic coast, from Long Island to Florida. 



The Fish Crow is a common and abundant resident, during- all seasons, 

 about the maritime districts of most and probably all of the southern 

 states. According- to Audubon they migrate northward in April and 

 ascend the Delaware river in Pennsylvania, nearly to its source, but re- 

 turn to the south at the approach of cold weather. This bird is also 

 found along the Susquehanna from Lancaster southward in the summer. 

 Mr. J. Hoopes Matlack informs me that some few years ago he found 

 the nest and eggs of this bird along the Brandywine creek, some two or 

 three miles from the borough of West Chester. Mr. Gentry writing in 

 1877, says he has observed it during the past five or six years nesting 

 along the water courses in the neighborhood of Philadelphia. This bird, 

 like the preceding species, builds in trees. The nests and eggs of the 

 Fish Crow, although smaller, cannot with absolute certainty be distin- 

 guished from those of the American Crow. The voice of the Fish Crow, 

 according to Wilson, is very different from that of the Common Crow, 

 being more hoarse and gutteral, uttered as if something had lodged in 

 the throat. The common note of this bird, Audubon says, resembles the 

 syllables ha, ha, hoe, frequently repeated. In referring to the food of 

 this species, Audubon writes substantially as follows : While searching 

 for food, these birds hover at a moderate height over the water ; but 

 when they rise in the air, to amuse themselves, they often reach a great 

 elevation. Like the Common Crow, the Fish Crow robs other birds of 

 their eggs and young. They also prey upon the fiddler-crab, which 

 they pursue and dig out of the muddy burrows into which they retire at 

 the approach of danger. Small fry are easily secured with their claws 

 as they fly close over the water's surface, from which they also pick up 



