National Geographic USA - 10.2019

Shell length: about 7 ft Weight: up to 2 tons

Stomach

300 ft

3 ft

2.3 ft

835 ft

Brain Salt glands

Skin Bone

Lungs

Liver

6 ft

4,000 ft

3 in Fat

Esophagus

Ribs

Scute

Veincool

blood

Arterywarm

blood

INDIANOCEAN PAC.OC.

ATL.OC.

SOUTHAMER.

EUROPE NORTHAMERICA

ANTARCTICA

AUS.

ASIA

AFRICA

OREGON, U.S.

NEW GUINEA^12 ,^774

mi

documentedLongest

sea turtlemigration

MAP SOURCES: SCOTT BENSON, SOUTHWEST FISHERIES SCIENCE CENTER, NOAA; STATE OF THE WORLD’S SEA TURTLES (SWOT), OBIS-SEAMAP

FLEXIBLE SHELL

Leatherbacks are the only living species with unfused ribs, rubbery

skin over layers of connective tissue, and a flexible shell of bony plates.

The hawksbill is the only turtle with

overlapping scutes and serrated edges

on its shell.

HAWKSBILLEretmochelys imbricata
Hawksbills’ intricately patterned, trans-lucent scutes have long been used to
decorate jewelry and luxury items.

OLIVE RIDLEY Lepidochelys olivacea

The most abundant species exits the sea en masse to nest, a safety-in-

numbers strategy against predators.

LEATHERBACKDermochelys coriacea

The largest and deepest diving turtle makes the longest migrations

and can weigh up to 2,000 pounds.

Slippery dietA long, barbed esoph-

agus traps jellyfish and keeps them moving

into the stomach.

Migration cuePale skin lets light into

the pineal gland, which can track day length

and spur migration.

ArchelonThis giant that roamed the (extinct)
seas 75 million years ago had unfused ribs, like its close rela-
tive, the modern leatherback.

Waxy skin covers a shell of coin-size bony plates

that can withstand the pressure of deep dives.

Transferring heatBlood flowing to flippers

warms returning cold blood, maintaining a warmer core

than hard-shell turtles have.