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Australian Federation Christmas Island_Crab spawning / incubation / spawning

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Australian Federation Christmas Island Christmas Island Travel Report (34th  

1 month old crab baby

Baby crab (5mm)

Crab hatching

Moment of spawning ・ The brown part is the egg

Standby for spawning

Male on the left and female on the right

■    During the spawning season from November to December, it takes 7 to 18 days to move from the forest to the coast.
■ Males arrive 5 to 7 days earlier than females, hydrate with seawater, and then dig a burrow.
■   Females enter the burrows dug by males and breed.
■ The male returns to the burrow in the mountains after hydrating with seawater.
■   The female lays an egg in the burrow (depth 80 cm) within 2 to 3 days.
■      Hold eggs for 12 to 13 days until they grow (100,000 eggs at a time)
■   Eggs in seawater on the morning of the new moon or at high tide before dawn.
■   Spawning lasts 5 to 6 days, and returns to land 1-2 days after spawning.
■   After spawning in the sea, it hatches immediately, and one month later, it becomes a larva shaped like a shrimp and returns to the Island.  
■   It becomes a crab of about 5 mm and heads inland for about 9 days.
■   It grows under fallen trees, branches and rocks for 3 years.
■   It takes 4 to 5 years to grow to 40 mm (shell width).

Crab spawning / incubation / spawning