Cerise crabs are native to Christmas Island, Australia. The central plateau of Christmas Island is dominated by strands of pelting forest. The island has a tropical climate and experiences both a wet season (Dec through April) and a dry out season (May through November).

More than 120 one thousand thousand scarlet venereal can be found on the pelting woods floor of Christmas Island. Red crabs alive alone in dirt burrows, or deep rock crevices. Crabs stay in the shade of their dwelling for near of the year. In October or November, when the wet season is about to render, crabs begin their migration to the shore. This timing coincides with the lunar cycle and the tides.

This video documents the 2nd phase of the red crab migration, after the crabs accept mated and before the eggs hatch in the bounding main. At the offset of this stage, females brood their eggs in dirt or littoral rock burrows for 12 to xiii days. A female cherry-red crab can lay up to 100,000 eggs, which she holds in her intestinal sac. With the arrival of the waning moon, females make their way into the sea. In what looks like a dance, females brace themselves at the waters border, and release their eggs.

  1. How many eggs can a female person crab produce?

    • Respond

      A female crab can produce up to 100,000 eggs.

  2. How many days does the female red crab sit with her eggs?

    • Reply

      The female scarlet crab sits on and protects her eggs for 12-13 days.

  3. What cues the crimson venereal to lay their eggs and begin migration?

    • Reply

      The waning moon cues the reddish crabs to lay their eggs. A waning moon means that the moon is decreasing in size, moving from a full moon towards a new moon. During this time, the moon takes on a crescent shape.

  4. What kind of tide is best for the female crabs to release their eggs?

    • Answer

      Carmine crabs release their eggs during mild or low tides, coinciding with the waning moon. Although the tide is low, many female person crabs drown as they attempt to release their eggs into the bounding main.

  5. Do most of the eggs survive to render every bit hatchlings?

    • Answer

      No, merely a handful of the hatched eggs survive and return to shore.

fauna migration

Noun

procedure where a customs of animals leaves a habitat for part of the year or role of their lives, and moves to habitats that are more than hospitable.

burrow

Noun

pocket-sized hole or tunnel used for shelter.

crab

Substantive

blazon of marine animal (crustacean) with a flat torso, hard shell, and pincers.

Noun

steady, predictable menstruation of fluid within a larger trunk of that fluid.

lunar cycle

Noun

complete cycle of visible phases of the moon, approximately 29.5 days.

Noun

movement of a group of people or animals from one place to another.

Substantive

large torso of salt h2o that covers most of the World.

offspring

Noun

the children of a person or animal.

Noun

large region that is higher than the surrounding area and relatively apartment.

Noun

surface area of alpine, generally evergreen trees and a loftier corporeality of rainfall.

Noun

rise and fall of the ocean's waters, caused by the gravitational pull of the moon and sun.

  • Credits

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    Editor

    Caryl-Sue, National Geographic Club

    Page Producer

    Makayla Trotter

    Producer

    Nina Page, National Geographic Society

    Terminal Updated

    Jan. xix, 2012

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