NORTH AMERICAN MARSH BIRDS 29 



perches, which were often filled with both of these species. We were 

 now in the center of the rookery; wading in mud and water nearly 

 to our armpits, where big alhgators had left their tracks on the 

 exposed mud banks, we soon came to the main nesting grounds of 

 the white ibises, in a thick growth of small trees and button bushes. 

 The place seemed alive with them; every tree and bush was as full 

 of their nests as possible, at heights varying from 4 feet above the 

 water to 14 feet or more. The nests were much smaller than the 

 spoonbill's nests, were made of lighter sticks and were not so well 

 made; they were lined with dry and green leaves. Some nests still 

 contained three or four eggs, but by far the greater number contained, 

 or had contained, young of various ages. Only the smaller young 

 remained in the nests when we approached; all that were half grown 

 or more began climbing out of the nests and traveling through the 

 branches to get away from us; there were hundreds of them, scram- 

 bling through the trees and bushes in droves; it was a lively scene. 

 Though awkward and ungainly in appearance, they were really 

 expert climbers and made surprisingly good progress, using bills and 

 wings as well as feet, in climbing and performing many acrobatic 

 stunts. Short falls were frequent and often they fell into the water; 

 where they went flopping off over the shallows or even swimming in 

 the deep open water. If not too hard pressed, they preferred to hud- 

 dle together in the tops of the trees. Many of them were already 

 on the wing. How the parents ever find their young in such confu- 

 sion is a mystery. 



Plumages. — The downy, young, white ibis is far from white. The 

 head is glossy black, the throat and neck brownish black, the back 

 is "mouse gray" and the under parts "pale mouse gray." The down 

 is short and thick on the head and short and scanty on the body. 

 The bill is pale flesh color with a black tip. 



The Juvenal plumage is a striking combination of dark brown and 

 wliite in marked contrast. The head and neck are mottled with 

 dark brown and grayish white; the upper back, wings and outer half of 

 the tail, are "clove brown" or "warm sepia" ; the lower back, upper tail 

 coverts and entire under parts are pure white. This plumage is worn 

 through the first summer and fall, without much change except a 

 gradual fading; by January the browns have faded to light, dingy 

 shades. In December the first prenuptial molt begins, with the ap- 

 pearance of a few wliite feathers in the back. The molt then spreads 

 during the late winter and early spring, involving the scapulars, wing 

 coverts, and tail, in varying amounts; generally some of the juvenal 

 rectrices are retained until the first postnuptial molt; and sometimes 

 a few new white secondaries arc acquired during the spring. In this 

 first nuptial plumage young birds show a great variety of color pat- 

 terns, but there is always more or less white, usually a preponder- 

 92G42— 26t 4 



