Australian rodent becomes first 'climate change extinction'

The Brown Rat - Rattus norvegicus

Australia officially declared a Great Barrier Reef rodent extinct on Tuesday, making it the first mammal believed to have been killed off by human-induced climate change.

The rat-like Bramble Cay melomys - whose only known habitat was a small sandy island in far northern Australia - has not been spotted in a decade.

Researchers from Queensland determined a key factor in its disappearance was "almost certainly" repeated ocean inundation of the cay - a low-lying island on a coral reef - over the last decade, which had resulted in dramatic habitat loss.

Australia's environment ministry on Tuesday said it had officially transferred the animal to the "extinct" list.

The declaration was expected. The researchers completed a wide-ranging survey in 2014 in a bid to track down the species, but found no trace.

Available data on sea-level rise and weather events in the Torres Strait region "point to human-induced climate change being the root cause of the loss of the Bramble Cay melomys", a study released in 2016 said.

The Melomys rubicola, considered the Great Barrier Reef's only endemic mammal species, was first discovered on the cay in 1845 by Europeans who shot the "large rats" for sport.