Ornithological biography, Vol. 3 (of 5)

by John James Audubon

Length 22 inches. Weight from 2 lb. to 2 1/2.

The Young acquire the full plumage in the course of the first winter.

THE WHITE IBIS.

Ibis alba, Vieill.
PLATE CCXXII. Adult Male, and Young.

Sandy Island, of which I have already spoken in my second volume, is remarkable as a breeding-place for various species of water and land birds. It is about a mile in length, not more than a hundred yards broad, and in form resembles a horse-shoe, the inner curve of which looks toward Cape Sable in Florida, from which it is six miles distant. At low water, it is surrounded to a great distance by mud flats abounding in food for wading and swimming birds, while the plants, the fruits, and the insects of the island itself, supply many species that are peculiar to the land. Besides the White Ibis, we found breeding there the Brown Pelican, the Purple, the Louisiana, the White, and the Green Herons, two species of Gallinule, the Cardinal Grosbeak, Crows, and Pigeons. The vegetation consists of a few tall mangroves, thousands of wild plum trees, several species of cactus, some of them nearly as thick as a man’s body, and more than twenty feet high, different sorts of smilax, grape-vines, cane, palmettoes, Spanish bayonets, and the rankest nettles I ever saw,—all so tangled together, that I leave you to guess how difficult it was for my companions and myself to force a passage through them in search of birds’ nests, which, however, we effected, although the heat was excessive, and the stench produced by the dead birds, putrid eggs, and the natural effluvia of the Ibises, was scarcely sufferable. But then, the White Ibis was there, and in thousands; and, although I already knew the bird, I wished to study its manners once more, that I might be enabled to present you with an account of them, which I now proceed to do,—endeavouring all the while to forget the pain of the numerous scratches and lacerations of my legs caused by the cactuses of Sandy Island.

As we entered that well-known place, we saw nests on every bush, cactus, or tree. Whether the number was one thousand or ten I cannot say, but this I well know:—I counted forty-seven on a single plum-tree. These nests of the White Ibis measure about fifteen inches in their greatest diameter, and are formed of dry twigs intermixed with fibrous roots and green branches of the trees growing on the island, which this bird easily breaks with its bill; the interior, which is flat, being finished with leaves of the cane and some other plants. The bird breeds only once in the year, and the full number of its eggs is three. They measure two inches and a quarter in length, with a diameter of one inch and five-eighths, are rough to the touch, although not granulated, of a dull white colour, blotched with pale yellow, and irregularly spotted with deep reddish-brown. They afford excellent eating, although when boiled they do not look inviting, the white resembling a livid-coloured jelly, and the yolk being of a reddish-orange, the former wonderfully transparent, instead of being opaque like that of most other birds. The eggs are deposited from the 10th of April to the 1st of May, and incubation is general by the 10th of the latter month. The young birds, which are at first covered with thick down of a dark grey colour, are fed by regurgitation. They take about five weeks to be able to fly, although they leave the nest at the end of three weeks, and stand on the branches, or on the ground, waiting the arrival of their parents with food, which consists principally of small fiddler crabs and crayfish. On some occasions, I have found them at this age miles away from the breeding-places, and in this state they are easily caught. As soon as the young are able to provide for themselves, the old birds leave them, and the different individuals are then seen searching for food apart. While nestling or in the act of incubating, these Ibises are extremely gentle and unwary, unless they may have been much disturbed, for they almost allow you to touch them on the nest. The females are silent all the while, but the males evince their displeasure by uttering sounds which greatly resemble those of the White-headed Pigeon, and which may be imitated by the syllables crooh, croo, croo. The report of a gun scarcely alarms them at first, although at all other periods these birds are shy and vigilant in the highest degree.

The change in the colouring of the bill, legs, and feet of this bird, that takes place in the breeding-season, is worthy of remark, the bill being then of a deep orange red, and the legs and feet of a red nearly amounting to carmine. The males at this season have the gular pouch of a rich orange colour, and somewhat resembling in shape that of the Frigate Pelican, although proportionally less. During winter, these parts are of a dull flesh colour. The irides also lose much of their clear blue, and resume in some degree the umber colour of the young birds. I am thus particular in these matters, because it is doubtful if any one else has ever paid attention to them.

While breeding, the White Ibises go to a great distance in search of food for their young, flying in flocks of several hundreds. Their excursions take place at particular periods, determined by the decline of the tides, when all the birds that are not sitting go off, perhaps twenty or thirty miles, to the great mud flats, where they collect abundance of food, with which they return the moment the tide begins to flow. As the birds of this genus feed by night as well as by day, the White Ibis attends the tides at whatever hour they may be. Some of those which bred on Sandy Key would go to the keys next the Atlantic, more than forty miles distant, while others made for the Ever Glades; but they never went off singly. They rose with common accord from the breeding-ground, forming themselves into long lines, often a mile in extent, and soon disappeared from view. Soon after the turn of the tide we saw them approaching in the same order. Not a note could you have heard on those occasions; yet if you disturb them when far from their nests, they utter loud hoarse cries resembling the syllables hunk, hunk, hunk, either while on the ground or as they fly off.

The flight of the White Ibis is rapid and protracted. Like all other species of the genus, these birds pass through the air with alternate flappings and sailings; and I have thought that the use of either mode depended upon the leader of the flock, for, with the most perfect regularity, each individual follows the motion of that preceding it, so that a constant appearance of regular undulations is produced through the whole line. If one is shot at this time, the whole line is immediately broken up, and for a few minutes all is disorder; but as they continue their course, they soon resume their former arrangement. The wounded bird never attempts to bite or to defend itself in any manner, although, if only winged, it runs off with more speed than is pleasant to its pursuer.

At other times the White Ibis, like the Red and the Wood Ibises, rises to an immense height in the air, where it performs beautiful evolutions. After they have thus, as it were, amused themselves for some time, they glide down with astonishing speed, and alight either on trees or on the ground. Should the sun be shining, they appear in their full beauty, and the glossy black tips of their wings form a fine contrast with the yellowish-white of the rest of their plumage.