It's a bird! It's a plane!
Okay, so maybe leatherback sea turtles can't leap tall
buildings in a single bound, but if there were a sea turtle
super-hero, the leatherback would be it. They have many
abilities and traits not seen in other sea turtles or even
other reptiles.
Leatherbacks can dive much deeper than any other sea turtle
species—to depths below 4,000 feet, a remarkable dive for an
air-breathing vertebrate. Only sperm whales and elephant seals
exceed such depths. And unlike all other sea turtles and
reptiles, leatherbacks are able to maintain their core (deep)
body temperature, which allows them to swim in waters as cold
as 40 degrees Fahrenheit, a temperature that would mean
lethargy or death for any other reptile species, which must
assume the temperature of their environment.
Leatherbacks are the largest of the sea turtles and the
largest living reptile, averaging six feet in length and
weighing approximately 1,200 lbs, although they can be larger.
In 1988, a leatherback was found measuring nine feet in length
and weighing nearly 2,000 pounds.
The leatherback carapace (shell) is different from that of
all other sea turtle species. Instead of the usual visible
scutes (bony plates), the leatherback's carapace is made up of
irregular bony plates covered with a tough leathery skin that
is permeated with oil, which helps insulate the leatherback in
colder waters. And while most sea turtles carapaces are
composed of keratin, the leatherback's carapace is made up
entirely of cartilage. It is dark grey to black with white
spots, and is divided into seven vertical sections running the
length of the turtle, separated by distinct bony ridges. The
leatherback carapace is designed more for swimming than for
protection, and it will bleed if scratched, which is why sharks
prey more on this species than any other sea turtle.
With their streamlined bodies, leatherbacks are the
strongest swimmers of all sea turtles.The leatherback's front
flippers are considerably longer than those of other sea
turtles, sometimes spanning eight feet, but they lack the claws
found on other sea turtles.
Surprisingly, the leatherback's amazing physical abilities
are fueled by a diet consisting almost exclusively of
jellyfish, of which a leatherback will consume almost twice its
weight per day. Thin, three-inch spines line the leatherback's
mouth and esophagus, helping it to catch and pulverize its soft
prey.
Leatherback nesting season occurs every two to three years,
six to nine times per season. Each nest contains approximately
120 eggs, only about 80 of which are viable. Hatchlings emerge
from the nest after a 65-day incubation period. At this point,
they are 2½" long and weigh approximately 1½ ounces. They are
mostly black and are covered in tiny scales. Their flippers are
edged in white, and their carapaces have seven rows of white
scales running down their length. Very few of the hatchlings
will survive to reach reproductive maturity, which occurs at
approximately 10 to 15 years.
Leatherbacks are highly migratory; they may be found in
oceans from Alaska to the tip of Africa. They inhabit the
Atlantic, Pacific, and Indian oceans, and regularly visit the
Pacific coast of North America. However, only during the
breeding season will leatherbacks enter coastal waters. From
February to July, nesting females can be found on warm tropical
beaches throughout the Caribbean, the northern coast of South
America, and the west coast of Central America. Each year, a
few nest on the east coast of Florida.
Unlike many sea turtle species, leatherback females often
change nesting beaches from year to year, making it difficult
for scientists to monitor nesting populations. However, based
on recent nesting populations at all known nesting beaches in
the Pacific, leatherback nesting is in serious decline.
The most obvious threat to leatherbacks are fishing
operations, whose nets and lines endanger all sea turtles.
Leatherbacks also suffer from water pollution and solid waste.
They sometimes ingest discarded plastic materials such as bags
and balloons, probably because they mistake the trash for
jellyfish. This plastic material causes suffocation,
strangulation, or blocked digestive tracts.
Another serious threat to leatherback survival is trade.
They are killed for the oil secreted on their carapace, which
is thought to contain medicinal qualities and is also used for
caulking boats as well as in oil lamps. In many countries,
leatherback eggs are collected and traded because they are
believed to be an aphrodisiac.
The leatherback is in serious decline throughout its range,
particularly in Mexico, India, Thailand, and Papua New Guinea.
Pacific leatherback populations appear to be in the greatest
danger from commercial fishing operations and pollution; they
are, in fact, the most endangered sea turtle in the Pacific
Ocean. The leatherback has been designated endangered under the
U.S. Endangered Species Act since 1970. It is protected
internationally by an Appendix I listing by the Convention on
International Trade in Endangered Species of Wild Fauna and
Flora (CITES), forbidding any international trade in
leatherbacks, their eggs, or products derived from them.
