Parliamentary Secretary to the Minister for the Environment and Heritage
Greg Hunt MP
11 March 2005
Mr Greg Hunt, Parliamentary Secretary with responsibility for Australia's land-based National Parks has announced that hundreds of thousands of baby red crabs emerged from the sea around Christmas Island this month after a remarkably successful breeding migration gave the rare species a population boost.
The island off Western Australia houses the only place in the world that the crabs are found, and after several years of poor survival this baby boom is particularly welcome.
"The baby red crabs march up into the forest in dense columns - it is truly spectacular," Mr Hunt said.
"Most years none of the baby crabs survive - they spend their first month in the ocean as plankton, and have to evade the large numbers of whale sharks and other predators that they attract.
"To see an entire generation survive to re-populate the island is remarkable."
The baby red crabs eventually find shelter under logs and rocks where they feed out of sight for the next two years. The adult red crabs march from the forests to the sea each year to spawn.
"They normally only breed after the rains start in October or November, and it was thought they needed the warm, wet weather to reproduce," Mr Hunt said.
"This year they have surprised us all and spawned despite the lack of rain, making three large breeding migrations down to the sea in December, January and February, plus a rare fourth migration in March.
"Sadly no babies survived the first two migrations, but the February migration was very successful, with large numbers of baby crabs emerging all round the island in early March.
"Parks Australia is conducting research into their marine planktonic phase to find out more about why the return of baby crabs is so uncommon."
The $30 000 research project is funded by Parks Australia, and also monitors movements of whale sharks which feed on the crab larvae.
"This year's return is the first large one after the deaths of large numbers of adult crabs at the height of the crazy ant eruption a few years ago," Mr Hunt said.
Very little information exists on the larval stages of any species of crab. Knowledge of their marine life cycle may help to improve red crab management in the future.
Fiona Murphy (Mr Hunt's office) 0423 577 045