Page 90 - Reptiles & Dinosaurs (Britannica Illustrated Science Library)

86 HUMANS AND REPTILES REPTILES AND DINOSAURS 87

Endangered

arine turtles are in danger of extinction. Their need to leave the water to breathe makes
them very easy to catch. Females and their offspring are at the greatest risk because they HAWKSBILL LEATHERBACK MESOAMERICAN
M build exposed nests on the shore where they can easily be attacked by hunters and egg TURTLE SEA TURTLE RIVER TURTLE
collectors. Others die when they are trapped in fishing nets. Marine turtles' nesting sites are also Eretmochelys Dermochelys Dermatemys mawii
at risk because of the effects of coastal urbanization. Artificial light drives females from the imbricata coriacea
routes they naturally take to lay their eggs. The offspring suffer from the same Status Critical Status Endangered Status Endangered
problem and become confused, unable to find their way. Habitat Warm Atlantic Habitat Tropical Waters Habitat Central America and Mexico
Size 2 to 2.5 feet (60-80 cm) Size 4 to 6 feet (1.3-1.8 m) Size 1.5 to 2 feet (50-65 cm)
The hawksbill is one of the smallest sea The leatherback, the largest marine Although turtles have developed
turtles and is easily recognized by its turtle, is one of the world's foremost adaptations for swimming, such as palm-
shell, which has a central keel and migratory animals: it routinely crosses shaped feet and a hydrodynamic shell, they
toothed edges. The beautiful designs on the Atlantic Ocean. The beaches where are practically defenseless on land. They
their shells have caused this species to they nest and lay their eggs are now have very short tails, and the females have
be savagely hunted. Hawksbills have a threatened by development related to olive green coloring on the upper portions
long life span and migrate less than tourism. of their heads. They lay between six and 20
other marine species. eggs in the marshy banks of rivers and are
hunted by coypu (nutria) and humans.

GREEN SEA PACIFIC PANCAKE
TURTLE RIDLEY TORTOISE
Chelonia Lepidochelys Malacochersus
mydas olivacea tornieri

Status Endangered Status Endangered Status Vulnerable
Habitat Tropical Waters Habitat Gulf of Mexico Habitat East Africa
Size 3 feet (1 m) Size 1.5 to 2.5 feet (50-75 cm) Size 5.5 to 7 inches (14-17 cm)
The green sea turtle is one of the most The Pacific ridley (olive ridley) has a The shell of the pancake tortoise is not
common sea turtles. It is found in round-shaped greenish-gray shell with only very flat but also very flexible
tropical and subtropical waters around five costal scutes. Its mouth is beaklike, because of the openings in the bone on its
the world. It has been a primary victim similar to that of a parrot, and its underside. This feature allows it to crawl
of commercial fishing. Green sea preferred diet consists of crustaceans and into narrow cracks to escape from
turtles are also in peril because of benthic mollusks. It is the smallest of the predatory birds and mammals. It can also
changing conditions on the beaches sea turtles and the species under the squeeze itself into holes.
where they mate. greatest threat of extinction.

GALAPAGOS YELLOW-
Migration TORTOISE MARGINED
LOGGERHEAD Geochelone BOX TURTLE
SEA TURTLE Some turtles travel great distances nigra Cuora flavomarginata
Caretta to reach the beaches where they
caretta will lay their eggs. The Laud turtle Status Vulnerable Status Endangered
is capable of crossing the entire Habitat Galapagos Islands Habitat China, Taiwan
Status Endangered Atlantic Ocean. Size Up to 4 feet (1.2 m) Size 8 inches (20 cm)
Habitat Tropical Waters
Size 4 feet (120 cm) The shell and other characteristics of The population of this turtle has decreased
these tortoises have evolved in significantly in recent decades because of
The loggerhead is a marine turtle that distinctive manners according to the the expansion of agriculture. The
inhabits the coasts of tropical seas and can conditions of each island where the population remaining in Taiwan has
stabilized and now shows signs
migrate great distances during its species is found—especially conditions of of recovery. Those in China, on
climate and nutrition. Many have
reproductive period. It lives in deep waters developed overgrown extremities to the other hand, remain in
but is sometimes found near the shore. It is
carnivorous but obtains food from a variety of reach their food. They can no longer be great danger.
sources depending on its age. found on some islands.