Other common names: Hawksbill
Turtle, Hawksbill, Hawksbill Seaturtle, Carey in Latin America
(Witherington, 2006)
The Hawksbill
Sea Turtle, Eretmochelys
imbricata, is the most beautiful of sea turtles,
and the lovely amber & black sunburst patterns on the
scutes of its carapace have made its shell in great demand
for many types of ornamental items, such as combs, glasses
frames, oriental fans, and musical instrument parts.
The hawksbill is a small to medium size sea turtle with
a weight of 40-80 kg (88 to 176 lbs) and a carapace length
of from 75 to 90 cm (30 to 35 in) (Witherington, 2006). It
can be identified by its hooked, bird-like beak, its beautifully
patterned shell that features overlapping scutes, its small
head, a long neck, two claws on each flipper, and its narrow
heart-shaped carapace with serrated edges. It has two pairs
of prefrontal scales and 4 pairs of lateral scutes, distinguishing
it from Loggerhead
Sea Turtles, Caretta
caretta, which have five. Its shell may feature
a range of colors, including yellow, gold, cream, brown,
amber, rust and black. The underside, or plastron, is typically
cream-colored, as are its fins, which are spotted with dark
scales. The shells of older hawksbills sometimes become home
to Chelonibia barnacles.
Hawksbill Sea Turtles are found in tropical waters throughout
the world, and most frequently reside in the vicinity of
coral reefs. They prefer shallower waters of 18 meters or
less and are often found resting under coral ledges, outcroppings,
and in other sheltered areas, such as caves. They hide for
protection in crevices and are adept at maneuvering.
Hawksbills are unusual in that their preferred food is the
sponge. Sponges are toxic to most animals, and certain species
contain slivers of glass-like silica. Some humans have died
after eating the meat of the hawksbill that contained residual
sponge toxins. Other foods eaten by hawksbills are jellyfish,
snails, mollusks, anemones, sea urchins, crustaceans, sea
plants, and scavenged fish and squid.
Unlike the Olive
Ridley Sea Turtle, Lepidochelys
olivacea, and Kemp’s
Ridley Sea Turtles, Lepidochelys
kempii, Hawksbill Sea Turtles do not nest in large
groups, but seek out isolated nesting spots on the tropical
island beaches and quiet continental coasts where they
were born. Thanks to their small size and maneuverability,
they are able to climb around obstacles to seek out protected
nesting spots that would be inaccessible to larger species.
Their success in choosing nesting spots that are difficult
for poachers to find may be one reason they have survived
as a species.
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| Picture of hawksbill
sea turtle, Eretmochelys
imbricata, Bahamas, Caribbean
Sea, Atlantic Ocean. |
Image
#: 013437 |
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Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Reptilia
Order: Testudines
Suborder: Cryptodera
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Hawksbills nest about 5 times during a laying season, which
occurs every two to three years. Each clutch contains about
130 brown eggs. It takes two months for the hawksbill eggs
to hatch and the 4 cm (2 inch) babies emerge at night and are
said to use reflected light on the water as their guide to
the sea. They are sometimes confused by reflected car or streetlights
and head in the wrong direction.
Hawksbill hatchlings typically go through a pelagic period
where they disperse into the open ocean for a few years,
and then return to shallow waters when they reach 20 to 30
cm (8 to 12 inches) in length. However, research suggests
that hawksbills from Hawaii and the Seychelles may skip this
pelagic period and stay close to home all their lives. It
takes hawksbills 20 to 40 years to become adults. Their average
longevity is not known.
Despite the hawksbill’s efforts to conceal its eggs, they
are sometimes found and consumed by people, dogs, rats and
raccoons. Herons, gulls and crabs intercept hatchlings as
they travel from their nest to the sea. If they manage to
reach the sea, they are then preyed upon by humans, sharks,
crocodiles, octopuses, and large fish. These dangers, along
with the marketability of their shell, make them highly threatened
as a species.
Biologists believe that the population of Hawksbill Sea
Turtles has gone down by 80% in the last 100 years. Fewer
than 15,000 nesting females reach worldwide shores each year
to lay eggs. The IUCN lists the hawksbill as Critically Endangered.
For a diagram helpful in identifying the hawksbill sea turtle,
see: http://marinebio.org/species.asp?id=164
• Hawksbill Sea Turtle information assembled from published
and on-line sources by Kevin
Miller on Nov. 9, 2006 for SeaPics.com.
Sources:
Perrine,
D. Sea Turtles of the World, Voyageur Press, 2003.
Ripple,
J. Sea Turtles, Voyageur Press, 1996.
Witherington,
B. Sea Turtles, Voyageur Press, 2006.
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