Crocodiles at sea
Can crocodiles live in the sea? Mossi,
Someplace, World
 A
10-foot (3 m) Australian saltwater crocodile basking on a sand bank along the
Daly River in Australia. Photo courtesy of Adam Britton,
crocodilian.com, copyright, used with permission
Most crocodile species live in fresh or brackish water.
They can tolerate some saltwater, since they have special tongue glands to
remove excess salt. However, one species tolerates saltwater
well, and lives sometimes in saltwater. This species spends the wet season in fresh
water. During the dry season, a saltie moves into brackish water, and
makes occasional forays out to sea.
How far a saltie moves into brackish water, depends partly on his social status. Dominant territorial
adults breed in freshwater; their young grow up there. Eventually,
however, the dominant adults force the sub-adults out of the freshwater areas,
says zoologist
Adam
Britton. The sub-adults that can establish a territory in their tidal
river stay in salty waters near their tidal river system. But those sub-adults that can't
establish territory are in trouble. The
dominant adults will either "kill them or force them out to sea" where they
must hunt for
another tidal river.
They don't live
at sea long, but can move around the coast between rivers, and occasionally
between offshore islands. Sea life dehydrates them quickly.
"But saltwater crocodiles can cope better than
any other crocodile species in salty water," says Britton.
By the way, the Australian saltwater crocodile is the world's most massive living reptile, reaching
lengths of up to 20 feet (6 m).
Further Reading:
Crocodilian Species List, Australian saltwater crocodile, Crocodilians
Natural History and Conservation
Alligators and Crocodiles, the San Diego Zoo
Comments:
Interesting. What about alligators? Are they more likely to be salt water
denizens? Sukumar, Chennai, India
That's less likely, Sukumar. According to the
San Diego Zoo, alligators do have special glands in their tongue to get rid
of excessive salt. But alligator's glands don't work as well as
crocodile's do. So they prefer freshwater.
This photo indicates they can end up in brackish waters, though:
http://www.thejump.net/alligators-etc/2-alligators-2/alligators-3.htm
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