The Christmas Island Red crab (Gecarcoidea natalis) is a species of land crab that is endemic to Christmas Island in the Indian Ocean. Low numbers are also found on North Keeling Island, thought to be from larvae drifted from Christmas Island and never been observed to breed. Although restricted to a relatively small area, it has been estimated that 43.7 million adult Red crabs once lived on Christmas Island alone, but the accidental introduction of the yellow crazy ant is believed to have killed about 10–15 million of these in recent years. Christmas Island Red crabs are well known for their annual mass migration to the sea to lay their eggs in the ocean.
Source: Wikipedia
Source: TheConversation.com
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