Our First Mammalian Casualty: The Extinction of the Bramble Cay Melomys

Not too long ago, I wrote a piece on our native rodents. Before I wrote that article I, like 80% of the people I’ve met, was… not a fan, to put it nicely. Researching our native species and their amazing relationship with our continent completely switched my brain around. I couldn’t believe that, in just one-fifth of Australia’s history as an isolated continent, our number of native rodent species grew from zero to sixty. I couldn’t believe that we actually had mice that used pebbles in their burrows! And some of our native rodents hopped like our marsupial species - I mean, that’s crazy, right? That is actually amazing. I couldn’t believe that there was all this diversity right at my feet and I had literally no idea.

There have been no sightings of the Bramble Cay melomys since 2009.

There have been no sightings of the Bramble Cay melomys since 2009.

Up until a few days ago, I also had no idea about another native rodent species, the mosaic-tailed rat, which was also known as the Bramble Cay melomys, or Melomys rubicola. Reddish-brown and small-eared, it had a tail scaled in a mosaic pattern, distinctive for the genus. The species was found only on Bramble Cay, a small vegetated coral cay in the Torres Strait. The species shared its home with sea turtles, shore birds, and a single lighthouse, the only artificial structure. In 1978, hundreds of Bramble Cay melomys were thought to have lived on Bramble Cay, foraging at night and burrowing through logs and debris. Numbers declined rapidly in the 1990s and 2000s, directly correlated with rising sea levels. In just ten years, 97% of their habitat was completely wiped out. In the last month, this native rodent, the only mammal endemic to the Great Barrier Reef, has been confirmed to be extinct. Not only that, it is the first mammal confirmed to be driven to extinction due to climate change.

For a lot of people, climate change probably doesn’t seem very real. I know in the past it has seemed rather abstract to me. I’ve learnt about it since I was in primary school, and it seems to have followed me as I’ve aged – discussed by teachers, lecturers, scientists, and politicians. There have been movies and documentaries, papers and popular books written about the phenomenon, warning me of what was to come. Still, I had always been able to distance myself from the reality of climate change – based in Melbourne, I’m relatively protected from the realities faced by so many other people and species. But when I recently read about the Bramble Cay melomys and discovered that scientists had recorded the first mammal to go extinct from climate change – and that this mammal was native to Australia – climate change no longer seemed like a far-off thing. Climate change is not ‘coming’ – it has arrived in full force, and it has claimed its first mammalian casualty here, in Australia.

The only artificial structure on the island, the Bramble Cay lighthouse sticks out amongst flocks of nesting seabirds. Image: Natalie Waller via The Conversation

The only artificial structure on the island, the Bramble Cay lighthouse sticks out amongst flocks of nesting seabirds. Image: Natalie Waller via The Conversation

Australia is home to so many endemic species, each of them amazing. From kangaroos to wombats, platypus to green tree frogs, the sheer number of species is difficult to think about. But now we are home to one less. We may not notice one species, the only mammal in the Great Barrier Reef, as it slipped away from us due to human-induced climate change – but we will miss the approximate one-sixth of all species on the planet that are estimated to disappear if we keep refusing to act. There are opportunities we can take to minimise the damage we’re causing and reduce our carbon footprint. Getting involved in charities like Cool Earth and Conservation Volunteers Australia are good places to start to learn how to give back.  

It is too late for the Bramble Cay melomys, but we owe it to our other native species to try.


Mary Shuttleworth

Mary Shuttleworth is a Masters graduate from the University of Melbourne, where she pursued her interests in ecology and parasitology. She is interested in science communication, education and community engagement.

Find her on Twitter at @muttersworth.


Banner image courtesy of Natalie Waller via The Conversation.