Mr. Audubon, whose account of the breeding-habits of the Ivory-bill is given from his own immediate observations, supplies a more minute and detailed history of its nesting. He states that it breeds earlier in spring than any other species of its tribe, and that he has observed it boring a hole for that purpose as early as the beginning of March. This hole he believed to be always made in the trunk of a live tree, generally an ash or a hackberry, and at a great height. It pays great regard to the particular situation of the tree and the inclination of the trunk, both with a view to retirement and to secure the aperture against rains. To prevent the latter injury, the hole is generally dug immediately under the protection of a large branch. It is first bored horizontally a few inches, then directly downward, and not in a spiral direction, as Wilson was informed. This cavity is sometimes not more than ten inches in depth, while at other times it reaches nearly three feet downward into the heart of the tree. The older the bird, the deeper its hole, in the opinion of Mr. Audubon. The average diameter of the different nests which Mr. Audubon examined was about seven inches in the inner parts, although the entrance is only just large enough to admit the bird. Both birds work most assiduously in making these excavations. Mr. Audubon states that in two instances where the Woodpeckers saw him watching them at their labors, while they were digging their nests, they abandoned them. For the first brood, he states, there are generally six eggs. These are deposited on a few chips at the bottom of the hole, and are of a pure white color. The young may be seen creeping out of their holes about a fortnight before they venture to fly to any other tree. The second brood makes its appearance about the 15th of August. In Kentucky and Indiana the Ivory-bill seldom raises more than one brood in a season. Its flight is described by Audubon as graceful in the extreme, though seldom prolonged to more than a few hundred yards at a time, except when it has occasion to cross a
large river. It then flies in deep undulations, opening its wings at first to their full extent, and nearly closing them to renew their impulse. The transit from tree to tree is performed by a single sweep, as if the bird had been swung in a curved line from the one to the other.
Except during the love-season it never utters a sound when on the wing. On alighting, or when, in ascending a tree, it leaps against the upper parts of the trunk, its remarkable voice may be constantly heard in a clear, loud, and rather plaintive tone, sometimes to the distance of half a mile, and resembling the false high note of a clarionet. This may be represented by the monosyllable pait thrice repeated.
The food of this Woodpecker consists principally of beetles, larvæ, and large grubs. They are also especially fond of ripe wild grapes, which they eat with great avidity, hanging by their claws to the vines, often in the position of a Titmouse. They also eat ripe persimmons, hackberries, and other fruit, but are not known to disturb standing corn nor the fruits of the orchard.
These birds attack decaying trees so energetically as often to cause them to fall. So great is their strength, that Audubon has known one of them to detach, at a single blow, a strip of bark eight inches long, and, by beginning at the top branch of a dead tree, tear off the bark to the extent of thirty feet in the course of a few hours, all the while sounding its loud notes.
Mr. Audubon further states that this species generally moves in pairs, that the female is the least shy and the most clamorous, and that, except when digging a hole for the reception of their eggs, they are not known to excavate living trees, but only those attacked by worms. When wounded, they seek the nearest tree, and ascend with great rapidity by successive hops. When taken by the hand, they strike with great violence, and inflict severe wounds with their bills and claws.
Mr. Dresser states that these birds were found on the Brazos River, and also on the Trinity, where they were by no means rare.
Wilson dwells at some length and with great force upon the great value of these birds to our forests. They never injure sound trees, only those diseased and infested with insects. The pine timber of the Southern States is often destroyed, thousands of acres in a season, by the larvæ of certain insects. In Wilson’s day this was noticeable in the vicinity of Georgetown, S. C., and was attributed by him to the blind destruction of this and other insect-eating birds.
An egg of this species (Smith. Coll., No. 16,196) taken near Wilmington, N. C., by Mr. N. Giles, measures 1.35 inches in length by .95 of an inch in breadth. It is of a highly polished porcelain whiteness, and is much more oblong in shape and more pointed than are the eggs of Hylotomus pileatus.