The Nesting of the Black Tern 



(Hydrochelidon nigra surinamensis) 



Charles Knapp Carpenter 



Naturalist. Elgin, 111. 

 (Wich photographs by the author) 



The black tern is found to be fairly common in northern Illi- 

 nois if one searches in suitable localities. 



It is a marsh bird and yet many marshes may be investigated 

 without finding this species. In other marshes, however, it may 

 be found in considerable numbers. 



Its irregular distribution leads some people more or less familiar 

 with birds to assert that it is only a bird of the ocean or of the 

 Great Lakes. A number of years ago, the author was delivering 

 a series of bird lectures at the Dixon (Illinois) Chautauqua and 

 made some reference to this bird being a native. During the 

 dinner hour, a gentleman at the hotel which stood on the bank 

 of Rock River was telling a group of men about the blunder made 

 by the lecturer, who when he entered the dining-room was taken 

 to task and was told that these birds were never to be found in 

 the interior of Illinois. Chancing to look out of the window over- 

 looking the river, he noticed a flock of them skimming the water 

 and "hawking" for insects. They were probably working south 

 from some marsh, and following the river. Calling the group 

 to the window he said, "Gentlemen, there they are." But they 

 are easily overlooked because of their being so restricted in their 

 habitat. 



The black tern is sometimes called the short-tailed tern to 

 distinguish it from its tern-cousins. Others compare it to a 

 swallow because of its manner of flight and long wings, and would 

 call it the Marsh Swallow. 



The tern is not quite ten inches long while the wing is over 

 eight inches in length. During the early breeding season, the 

 head, neck and lower parts are a sooty -black while the other 

 principal color is a silvery-grey or plumbeous. But during the 

 nesting season the moulting is taking place and the black feathers 

 are changing to white so that a person might think there were two 

 or three different species. 



The bird does not spend much time building the nest. Some 

 of the nests are built directly on the water where the growing grass 

 helps to support them; but usually a pile of floating vegetation 



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