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Hawk's-bill Turtle
- Colouration
- Carapace dark brown or black, richly marbled with yellow; plastron yellow. Shields of the head and limbs dark brown or black, margined with yellow.
- Dimensions
- Smallest of the sea turtles. The carapace of a very large animal will measure about two and a half feet in length; few examples of that length are captured nowadays.
- Habits
- Unlike its near ally, the Green Turtle, the present reptile is apparently carnivorous, living upon fish, crustaceans and molluscs. Like all of the marine chelonians, it lays its eggs on sandy beaches, above tide-line.
- Colour
- Very dark olive, or dark brown.
- Distribution
- North America east of the Rockies; southward to Ecuador.
- Colour
- Pale brown or yellowish.
- Distribution
- Rivers emptying in the Gulf of Mexico--Florida to Texas; northward to Missouri.
Distinguished from the other sea turtles by the loosely-overlapping (imbricate) shields of the carapace. The structure of the shields on the plastron is like that of the Green Turtle. Head, limbs and flippers covered with shields; head elongated, the upper mandible terminating in a pronounced hook or beak-hence the popular name. (See accompanying illustration.) Two claws on each front flipper.
It is from this sea turtle only, that the valuable "tortoise-shell" of commerce is obtained; this is the clear, horny substance, in the shape of shields, covering the bony carapace.
A Small Family, Composed of Three Large and Powerful Species
Classification.--Of the three species composing the family Chelydridae, two inhabit North America. The family is divided into two genera, Chelydra and Macrochelys. One species of the former is widely distributed and abundant in the United States and ranges southward to Ecuador; the other species inhabits Mexico and Guatemala. The single species of Macrochelys is confined to the Southern United States.
General characters.--The Snapping Turtles are the largest of the fresh-water chelonians inhabiting the United States. Their general form is well known. The dull, rough carapace, with its heavy keels and marginal serrations, the proportionately huge and sinister head, and the long, fleshy tail, with its alligator-like crest combine to make these turtles unique. The plastron is insignificantly small and narrow and affords comparatively no protection--but these big turtles do not seek to withdraw the head and limbs like their smaller and weaker relations. They are bold and aggressive fighters and their massive, keen-edged jaws cause them to be the terror of most of the aquatic and semi-aquatic creatures.
The Common Snapping Turtle (Chelydra serpentina), though larger than any other species of North American turtle, except its near ally, is dwarfed by the comparison of the latter species--the Alligator Snapping Turtle (Marcochelys lacertina). Adult specimens of this enormous, fresh-water turtle attain a weight of 130 and 140 pounds.
The genera may be defined, thus:
Under surface of tail with large shields. . . . Chelydra.
Under surface of tail with large scales. . . Macrochelys.
Besides these characters the following points may be employed in separating the two species inhabiting the United States:
a. Three moderate keels on the carapace.
COMMON SNAPPING TURTLE, Chelydra serpentina.
b. Three very high keels on the carapace.
ALLIGATOR SNAPPING TURTLE, Macrochelys lacertina.
The Snapping Turtles are herewith considered in detail: