Page 28 - Super Shark Encyclopedia

SHELL SHEDDER

BLUE SWIMMING CRAB

Big crabs are heavy on land because of their cumbersome hard shell, Back legs
but they are buoyant in the ocean—and this crab even has paddles to are used for
swimming
get around in midwater. Hard shells offer good protection, but are too
stiff to expand—so crabs must discard their old shell and make a new,
bigger one so that they can grow.

“Only one

AT A GLANCE
in a million

baby crabs

survives to

become an adult”
• SIZE 6½–10½ in (17–27 cm) shell diameter

• HABITAT Estuaries and bays with muddy
or sandy bottoms, going upstream into rivers
• LOCATION Western North America, Gulf of
Mexico south to Argentina, introduced to
Europe and Japan
• DIET Oysters, clams, mussels, worms, small fish,
seaweed, and carrion

STATS AND FACTS 6

WIDTH OF SHELL
3½ in/9 cm (males)
MILLION Thick muscles at the
in 1 2 3
MAX. EGGS PER SPAWNING
base of the claw pull on
flat blades to open and
cm 2 4 6 8 10
close the pincers
3 in/7.5 cm (females)
TIME 20 months to
complete all molts
Muscles in each leg
MOLTS IN A LIFETIME segment work in pairs:
months 10 20 30 40 50 UP TO one bends the leg, the
20
up to 48 months average lifespan other extends it

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