Red crabs are native to Christmas Island, Australia. The central plateau of Christmas Island is dominated by strands of rain forest. The island has a tropical climate and experiences both a wet season (December through April) and a dry season (May through November).
More than 120 million red crabs can be found on the rain forest floor of Christmas Island. Red crabs live alone in dirt burrows, or deep rock crevices. Crabs stay in the shade of their dwelling for most of the year. In October or November, when the wet season is about to return, crabs begin their migration to the shore. This timing coincides with the lunar cycle and the tides.
This video documents the third and final stage of the red crab migration, after the eggs have been released into the ocean. The crab larvae remain in the water for about a month, growing through several larval stages. Few are able to survive the harsh ocean currents and marine predators. Those that survive shed their larval casing and begin the journey back into the rain forest, battling predators, such as the yellow crazy ant, along the way.
How long do the red crab eggs drift in the ocean?
What guides young red crabs on their migration route?
What hazards do red crabs face at sea? What hazards do they face on land?
Term Part of Speech Definition Encyclopedic Entry animal migration Noun
process where a community of animals leaves a habitat for part of the year or part of their lives, and moves to habitats that are more hospitable.
small hole or tunnel used for shelter.
type of marine animal (crustacean) with a flat body, hard shell, and pincers.
to emerge from an egg.
danger or risk.
Indian Ocean Noun
one of Earth's four oceans, bordered by Africa, Asia, Australia, and Antarctica.
natural motivation or behavior.
a new or immature insect or other type of invertebrate.
lunar cycle Noun
complete cycle of visible phases of the moon, approximately 29.5 days.
movement of a group of people or animals from one place to another.
large body of salt water that covers most of the Earth.
Encyclopedic Entry: ocean plateau Noun
large region that is higher than the surrounding area and relatively flat.
Encyclopedic Entry: plateau predator Noun
animal that hunts other animals for food.
rain forest Noun
area of tall, mostly evergreen trees and a high amount of rainfall.
Encyclopedic Entry: Rain forest tide Noun
rise and fall of the ocean's waters, caused by the gravitational pull of the moon and sun.
Encyclopedic Entry: tide