They’re Back: Supposedly Extinct Sea Snakes Have Been Found in Australia

Nearly 15 years later and about 1,000 miles away from the last sighting, the snakes could be making a comeback

Sea Snakes
This photo of two short-nosed sea snakes alerted researchers to the species' survival, even though they were thought to be extinct for 15 years. Grant Griffin, W.A. Dept. Parks and Wildlife

Normally, spotting a large predatory sea creature would be cause for alarm. But when researchers came across a pair of yellow sea snakes near an Australian reef, they had reason to celebrate. The Washington Post’s Elahe Izade reports that the sighting proved that two species of sea snakes thought to be extinct actually still exist.

Izade writes that it was the first sighting of short-nosed sea snakes, or Aipysurus apraefrontalis, in nearly 15 years—and that the snakes appeared to have been breeding when they were spotted near Ningaloo Reef. Researchers also found a thriving population of another supposedly extinct species of sea snake, Aipysurus foliosquama or leaf-scaled sea snake. They wrote about the find in the journal Biological Conservation this week.

The two rediscovered species are native to Australian waters. But a 90 percent decline in population put them on the IUCN Red List of Threatened Species as Critically endangered.

The last spotting of the leaf-scaled sea snake happened in 2001 and the short-nosed sea snake in 2002. At that time, both species were thought to exist only in Ashmore Reef in the Timor Sea off of Northern Australia. However, the new discoveries were made about 1,000 miles away in Western Australia in entirely different types of habitat.

The find is great news, but it doesn’t explain why sea snake numbers are falling all over Australia. Some scientists hypothesize that their declining populations can be linked to coral reef bleaching. The researchers have another hypothesis: Since many of the snakes they found in their research were recovered by shrimp trawlers, the team thinks both species are vulnerable to trawling.

But it may not be enough to chalk up the sea snakes’ strange disappearance and migration to trawling alone. “Clearly we need to identify the key threats to their survival in order to implement effective conservation strategies” says Vimoksalehi Lukoschek, one of the paper’s co-authors, in a release. The sea snakes may be back for now, but until scientists understand what made them decline in the first place, their future remains uncertain.

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