National Geographic USA - 10.2019

(Joyce) #1
Ribs

Fat

CONSERVATION STATUS Esophagus
Critically endangered
Endangered
Vulnerable
Insufficient data


Shell length 3.5 ft (maximum)

Scute

3.1 ft

200 ft

Female

Claw

1 in

Scute
Rib

Stomach
Liver

4 ft

Brain

500 ft

PRIMARY ADULT DIET
Invertebrate
Marine plant
Horseshoe crab
Sponge
Crustacean
Mollusk
Fish


2.1 ft
Diet Maximum diving depth

585 ft

160 ft

Lungs

INDIANOCEAN

PACIFICOCEAN
PACIFICOCEAN

ATLANTICOCEAN
SOUTHAMER.

AMERICANORTH EUROPE

ANTARCTICA

AUS.

ASIA
EQUATOR AFRICA
Population athighest risk

Range

Nestingarea

FERNANDO G. BAPTISTA, JOHN KAPPLER, DIANA MARQUES, AND EVE CONANT, NGM STAFF; MESA SCHUMACHER SOURCES: JEANETTE WYNEKEN, FLORIDA ATLANTIC UNIVERSITY; BRIAN HUTCHINSON, RODERIC MAST, OCEANIC SOCIETY

SEA SURVIVORS


HARD SHELL


Sea turtles have navigated the oceans since the time of the dinosaurs
more than 100 million years ago. Today all seven species are under threat
at every life stage because of human activities, from accidental capture in
fishing nets to overharvesting of eggs and widespread plastic pollution.

Six of the seven species have hard shells fused to their ribs and over-
laid with keratin scutes. They also have claws on their flippers.


Illustrations in approximate,
relative scale

All sea turtles have glands around the eyes
to remove excess salt from their bodies.

Interlocking scutes pre-vent water loss and cover
flattened, fused ribs that separate at the tips.

Adult males can be identified by their
long tails, which hold sex organs.

Front flippers act as wings for propulsion.
Rudder-like hind feet stabilize and steer.

The green turtle’s serrated beak helps
tear marine plants.

KEMP’S RIDLEYLepidochelys kempii
Accidental capture and egg overhar-vesting have made the smallest sea
turtle the world’s most threatened.


LOGGERHEADCaretta caretta
The most abundant sea turtle in the U.S. is named for its giant head. Its
strong jaws can crack conch shells.

FLATBACKNatator depressus
The flatback makes the shortest migra-tion: around Australian waters. It has a
nearly flat body with flared edges.

GREEN Chelonia mydas
Named for a layer of green fat under their shell, green turtles start as omni-
vores before turning into herbivores.
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