Conservation Status

Not listed as threatened or endangered



--Red Crabs are known for their famous annual mass migration to the sea in order to lay their eggs. They migrate by the millions and can be seen from the air!

--Outside of the breeding season, red crabs are solitary and live in a humid burrow for most of the year.

--The eggs released by the female hatch immediately upon contact with the water.

Class: Malacostraca
Order: Decapoda
Family: Gecarcinidae
Genus: Gecarcoidea
Species: natalis


Length: 5 inches
Weight: 17 ounces
Life Span: Over 12 years
# of young: A female may brood up to 100,000 eggs
Range: Christmas Island in the Indian Ocean
Diet: Scavenger, eats fallen leaves and flowers and occasionally animals

Energy & Conservation

It is possible that the extremely large population of the Christmas Island Red Crabs may have been caused by the extinction of Maclear's Rat. This rat was thought to have been a possible predator of the crab, keeping their populations in check.

Humans also affect the red crab population. Thousands of crabs are crushed each year while crossing roads. In order to reduce the number of crabs killed by cars each year, crab crossings are being constructed. A crab crossing consists of a tunnel dug under the road in areas of dense migrations for the crabs to pass through.

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