What it is
The Bramble Cay melomys (Melomys rubicola) was a mosaic-tailed rat living only on Bramble Cay, a four-hectare coral islet in Torres Strait, Australia. IUCN lists it as Extinct. It ate herbaceous plants on a cay only a few metres above the sea.
Range
Bramble Cay alone. No other island held a population.
What happened
The last confirmed animal was seen in 2009. A thorough 2014 search found none; Queensland declared the species extinct in 2016. Repeated inundation and storm surge had stripped the vegetation that was its food and cover. Researchers (Woinarski, Waller, and others) identified anthropogenic sea-level rise as the main driver: the first mammal extinction widely assigned to climate change. Honesty still requires the other fact: a species confined to one wash-over cay was already extremely vulnerable.
When / status
Extinct. Last seen 2009; formal declarations 2016 (Queensland) and IUCN EX.
Human role
Climate-driven loss of a tiny island habitat: not hunting. The small range made the climate impact fatal.
Sources
IUCN Red List (Melomys rubicola, EX); GBRMPA/Queensland 2016 report; Woinarski and Waller analyses of climate-driven extinction.