trees, but only occasionally fed upon them. In the 

 Mississippi Delta region, they nested only in var- 

 ious species of hardwood trees (at least in the 

 Singer Tract), in parts of the woods where the 

 ground was at least partly covered with water dur- 

 ing the nesting season (Tanner 1942). 



A characteristic of all habitats used by ivory- 

 bills is that other species of woodpeckers, such as 

 the pileated and red-bellied woodpeckers, reach 

 their greatest abundance there also. The most 

 likely places to look for ivory-bills are bottom- 

 land forests where big sweet gums and oaks are 

 abundant, where there are many dead and dying 

 trees, and where other woodpeckers are abundant. 

 The many dying and dead trees in old age stands 

 of timber contain the wood-boring insects eaten 

 by the woodpeckers. The sweet gum-oak bottom- 

 land forests supply the best feeding conditions on 

 the Mississippi Delta. The wood-boring insects are 

 most abundant in wood 2 or 3 years dead from 

 storm, fire, logging, or disease. These conditions 

 occur most often in large, old forests, and their 

 elimination or isolation has made it increasingly 

 difficult for ivory-bills to find sufficient food and 

 to move from one area to another in search of a 

 variable food supply that has always been more or 

 less eruptive and undependable (Tanner 1942). 

 Virgin haidwood is not a necessity and pines are 

 more important than Tanner thought in the 

 Neches River Valley (Dennis 1967). 



The ivory-bill is a nomadic "disaster species," 

 moving into areas where trees have been killed by 

 fire, storms, insect attack, or flooding (Dennis 

 1967). Observations in Texas and Florida by 

 Herbert Stoddard and John Dennis convinced 

 them that old age or virgin hardwood forests are 

 not essential as long as there are large numbers 

 of recently dead trees to supply the type of 

 wood-boring grubs prefened by ivory-bills. They 

 thought that dead pine trees, including recently 

 cut slash, were frequently used (Dennis 1967). 



C. p. bairdii. Gunclach (1876) found Cuban 

 ivory-bills in the high country of Pinar del Rio 

 and also in low country along river bottoms simi- 

 lar to the habitat of the American ivory-bill, near 

 Guantanamo in eastern Cuba. During the last half 

 of the 19th century, Cuban ivory-bills were found 

 mainly in high country in pine forests on deep 

 lateritic soil. They feed in both hardwoods and 

 pines, but nest and roost almost exclusively in old 

 pine trees (Pinus cubensis) (Lamb 1957). The 

 lateritic soil, composed of small, hard nodules of 

 iron ore, drains very quickly and completely, so 

 that it can support pine forest up to about 300 m 



elevation. Above that, hardwood becomes domin- 

 ant. Most of the pine land has been lumbered, but 

 the birds have managed to adapt to changing habi- 

 tat, living in large dead pines that are still standing 

 and feeding on dead pines and dead hardwoods, 

 both of which are infested with wood-boring 

 beetles. They roost and nest only in pines, and 

 large enough pines are becoming rare.' 



FOOD AND FORAGING 



C. p. principalis. Audubon (1842) mentions 

 grapes, persimmons £ind blackberries as food of 

 ivory-bills, in addition to beetles and their larvae. 

 Allen and Kellogg (1937) found ivory-bills digging 

 trenches in rotten wood, as plicated wood- 

 peckers do, to get at the large wood-boring beetle 

 larvae. More often, they scaled off bark from 

 recently dead trees or from dead branches of liv- 

 ing trees to get at insects and larvae hidden be- 

 neath. Most feeding was in dead pines at the 

 edges of swamps. They sometimes fed on the 

 ground like flickers. 



The most common feeding behavior is to 

 knock the bark off recently dead trees with side- 

 wise blows or quick flicks of the bill to uncover 

 and eat the borers that live between the bark and 

 the sapwood. When feeding the young, they hold 

 grubs in the back of the bill while continuing to 

 scale bark for additional food. Grubs 2.5 to 5 cm 

 long are used to feed young. Ivory-bill workings 

 for food show as bare places on recently dead 

 limbs of trees where the bark has been scaled off 

 clean for a considerable extent. Pileated wood- 

 peckers do some scaling, but it is usually confined 

 to smaller limbs and to those longer dead. They 

 obtain most of their food by digging in the wood, 

 while ivory -bills obtain theirs by scaling the bark. 

 Extensive scaling of bark from a tree so recently 

 dead that the bark is still tight, with a brownish 

 or reddish color of the exposed wood showing 

 that the work is fresh, is one good indication of 

 the presence of ivory-bills (Tanner 1942). How- 

 ever, they do also chisel into the wood, making 

 somewhat conical holes. In the Singer Tract, 

 Louisiana, most feeding was on sweet gum. Nut- 

 tail's oak, and hackberry, over 30 cm in diameter. 

 Wandering and ranges of ivory-bills are prob- 

 ably controlled by abundance of food. They re- 

 quire an unusually large supply of certain wood- 

 boring insects which make up most of their diet 

 and which is abundant only in occasional localities 

 for a comparatively short period. Birds remain in 

 one locality as long as the food lasts, then move, 

 sometimes for considerable distances, until they 



