Page 91 - Reptiles & Dinosaurs (Britannica Illustrated Science Library)
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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.
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