Melbourne: Australia’s sea snakes are at the risk of extinction, marine biologists have warned.
A genetic study has revealed turtleheaded snakes rarely breed with individuals on other reefs in Australia, so if one population was wiped out, it’s unlikely to be “replenished” by neighbouring snakes.
The biologists from the ARC Centre of Excellence for Coral Reef Studies and the University of Sydney used genetic “fingerprinting” to show that this behaviour has resulted in significant genetic differentiation in populations of the sea snakes, Emydocephalus annulatus, living on adjacent reefs.
These snakes occur in shallow water coral reef habitats from the Philippines to the Great Barrier Reef and from New Caledonia to north western Australia.
“The genetic divergence we found confirms that snakes rarely travel to other locations to mate, regardless of the distance, and means that if one population were to decline or disappear, it is unlikely to be ‘replenished’ by neighbouring snakes, because snakes rarely move between reefs,” said lead researcher Dr Vimoksalehi Lukoschek in a release.
Added co-researcher Prof Rick Shine: “For eight years, sea snakes on two reefs that are adjacent to each other in New Caledonia have been captured, tagged with a microchip device and released. In almost all instances, snakes were repeatedly re-captured on the same reef during summers and winters.”
According to the marine biologists, the implications are that coral reef sea snakes are extremely vulnerable to disturbances in their local habitats, which could be caused by human activities or environmental changes.
Dr Lukoschek said: “This is of great concern, given that some Australian populations of turtleheaded and other reef-associated sea snakes have undergone massive declines or local extinctions in recent years, particularly at Ashmore Reef in the Timor Sea, and also on some reefs in the southern Great Barrier Reef.”
The findings have been published in the latest edition of the ‘Ecology and Evolution’ journal.