62 BULLETIN 135, UNITED STATES NATIONAL MUSEUM 



quite bare, as well as a portion of the upper part of the neck. In the fourth 

 year, the bird is as you see it in the plate. The male is much larger and heavier 

 than the female, but there is no difference in color between the sexes. 



The complete molt of the adult apparently occurs in September 

 and October; I have seen no evidence of a molt in the spring or of 

 any seasonal difference in plumage. 



Food. — The wood ibis is mainly a fresh water bird and prefers to 

 feed in shallow, muddy ponds, marshes and sloughs; but it also re- 

 sorts occasionally, perhaps often to salt-water mud flats and shoals. 

 I frequently saw them in winter, usually from two to four birds, 

 feeding on the extensive mud flats of Boca Ceiga Bay in company 

 with American egrets, little blue, Louisiana, and Ward herons. They 

 must fly long distances to feed, for this locality, in Pinellas County, 

 Florida, is at least 100 miles from the nearest known rookery. Two 

 birds were seen occasionally in a little pond hole on Long Key beside 

 a much frequented road, where they fed with the egrets, totally un- 

 concerned with many passing automobiles. I once sat and watched 

 them feeding within 20 yards of my blind and was much impressed 

 by the loud clattering of their bills, as they walked about with long, 

 deliberate steps, feeling for their food and scooping it out of the mud 

 and water. A method of feeding, that 1 have never seen or read 

 about, is described in some notes sent to me by Mr. Kennard, based 

 on observations made by his guide. He reported watching a num- 

 ber of them at close range. They were in some open water with a 

 very muddy bottom, walking back and forth, dragging their bills 

 beside them, pointed downward and backward, opening and shut- 

 ting them repeatedly, as if sifting the mud through them, after the 

 manner of flamingos, lie says that on moonlight nights numbers 

 of them may be seen feeding in the sloughs; and on a cloudy, rainy 

 day they could be seen all over the prairie, feeding, perhaps on 

 grasshoppers. 



Audubon's (1840) account of the feeding habits of the wood ibis 

 is worth quoting, as follows: 



This species feeds entirely on fish and aquatic reptiles, of which it destroys an 

 enormous quantity, in fact more than it [eats; for if they have been killing fish 

 for half an hour and have gorged themselves, they suffer the rest to lie on the 

 water untouched, when it becomes food for alligators, crows, and vultures, when- 

 ever these animals can lay hold of it. To procure its food, the wood ibis walks 

 through shallow muddy lakes or bayous in numbers. As soon as they have dis- 

 covered a place abounding in fish, they dance as it were all through it, until the 

 water becomes thick with the mud stirred from the bottom by their feet. The 

 fishes, on rising to the surface, are instantly struck by the beaks of the ibises, 

 and, on being deprived of life, they turn over and so remain. In the course of 

 10 or 15 minutes, hundreds of fishes, frogs, young alligators, and water snakes 

 cover the surface, and the birds greedily swallow them until they are completely 

 gorged, after which they walk to the nearest margins, place themselves in long 

 rows, with their breasts all turned toward the sun, in the manner of pelicans and 



