Monday, September 19, 2005

Audubon Observes Florida Sea-Turtles

During an 1832 trip to Florida and the Tortugas, the naturalist James Audubon had the opportunity to study the region's large Turtles: the Green (Chelonia mydas), the Hawk-billed (Eretmochelys imbricata), the Logger-head (Caretta caretta) and the Trunk [Leatherback] (Dermochelys coriacea), Turtles. The following is an excerpt, on their nesting behavior, from his observations:

But the Tortugas are not the only breeding places of the Turtles; these animals, on the contrary, frequent many other Keys, as well, as various parts of the coast of the mainland. There are four different species which are known by the names of the Green Turtle, the Hawk-billed Turtle, the Logger-head Turtle and the Trunk Turtle. The first is considered the best as an article of food, in which capacity it is well known to most epicures. It approaches the shores, and enters the bays, inlets, and rivers, early in the month of April, after having spent the winter in the deep waters. It deposits its eggs in convenient places, at two different times in May, and once again in June. The first deposit is the largest, and the last the least, the total quantity being, at an average, about two hundred and forty. The Hawk-billed Turtle, whose shell is so valuable as an article of commerce, being used for various purposes in the arts, is the next with respect to the quality of its flesh. It resorts to the outer Keys only, where it deposits its eggs in two sets, first in July, and again in August, although it "crawls" the beaches of these Keys much earlier in the season, as if to look for a safe place. The average number of its eggs is about three hundred. The Logger-head visits the Tortugas in April, and lays from that period until late in June three sets of eggs, each set averaging one hundred and seventy. The Trunk turtle, which is sometimes of an enormous size, and which has a pouch like a Pelican, reaches the shores latest. The shell and flesh are so soft that one may push his finger into them, almost as into a lump of butter. This species is therefore considered the least valuable, and, indeed, is seldom eaten, unless by the Indians, who, ever alert when the Turtle season commences, first carry off the eggs, and afterwards catch the Turtles themselves. The average number of eggs which it lays in the season, in two sets, may be three hundred and fifty.

The Logger-head and the Trunk Turtles are the least cautious in choosing the places in which to deposit their eggs, whereas the other two species select the wildest and most secluded spots. The Green Turtle resorts either to the shores of the Main, between Cape Sable and Cape Florida, or enters Indian, Halifax, and other large rivers or inlets, from which it makes its retreat as speedily as possible, and betakes itself to the open sea. Great numbers, however, are killed by the turtlers and Indians, as well as by various species of carnivorous animals, as Cougars, Lynxes, Bears, and Wolves. The Hawk-bill, which is still more wary, and is always the most difficult to surprise, keeps to the sea-islands. All the species employ nearly the same method in depositing their eggs in the sand, and as I have several times observed them in the act, I am enabled to present you with a circumstantial account of it.

On first nearing the shores, and mostly on fine, calm, moonlight nights, the Turtle raises her head above the water, being still distant thirty or forty yards from the beach, looks around her, and attentively examines the objects on the shore. Should she observe nothing likely to disturb her intended operations, she admits a loud hissing sound, by which such of her enemies as are unaccustomed to it are startled, and so are apt to remove to another place, although unseen by her. Should she hear any noise, or perceive any indications of danger, she instantly sinks, and goes off to a considerable distance; but should everything be quiet, she advances slowly towards the beach, crawls over it, her head raised to the full stretch of her neck, and when she has reached a place fitted for her purpose, she gazes all round in silence. Finding "all well" she proceeds to form a hole in the sand, which she effects by removing it from under her body with her hind flippers, scooping it out with so much dexterity that the sides seldom if ever fall in. The sand is raised alternately with each flipper, as with a large ladle, until it has accumulated behind her, when, supporting herself with her head and fore part on the ground fronting her body, she, with a spring from each flipper, sends sand around her, scattering it to the distance of several feet. In this manner the hole is dug to the depth of eighteen inches, or sometimes more than two feet. This labor I have seen performed in the short period of nine minutes. The eggs are then dropped one by one, and disposed in regular layers, to the number of a hundred and fifty, or sometimes two hundred. The whole time spent in this part of the operation may be about twenty minutes. She now scrapes the loose sand back over the eggs, and so levels and smooths the surface that few persons on seeing the spot could imagine anything had been done to it. This accomplished to her mind, she retreats to the water with all possible dispatch, leaving the hatching of the eggs to the heat of the sand. When a Turtle, a Logger-head for example, is in the act of dropping her eggs, she will not move, although one should go up to her, or even seat himself on her back, for it seems that at this moment she finds it necessary to proceed at all events, and is unable to intermit her labor. The moment it is finished, however, off she starts; nor would it then be possible for one, unless he were as strong as Hercules, to turn her over and secure her.

Audubon and His Journals ed. Maria R. Audubon. New York: Scribner's Sons, 1897. (Dover Reprint, 1960.) II, 373-75.

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