The Australian government has confirmed the extinction of a small rodent native to a tiny spit of sand in the northernmost part of the Great Barrier Reef ― the first known mammal lost to human-caused climate change.
Bramble Cay melomys lived on the coral island of Bramble Cay, located in the Torres Strait between Queensland state and Papua New Guinea. The Government of Queensland initially declared the species extinct in a 2016 report, and Australian Environment Minister Melissa Price confirmed the die-off in a press release this week. The whiskered rat has been officially reclassified from “endangered” to “extinct.”
Geoff Richardson, an official with Australia’s Department of the Environment and Energy, told lawmakers on Monday that the declaration “was not a decision to take lightly,” according to The Sydney Morning Herald.
“There’s always a delay while the evidence is gathered to be absolutely certain,” he said.
It is estimated that several hundred Melomys rubicola roamed the island in the late 1970s, according to the 2016 report co-authored by researchers at the University of Queensland. By the late 1990s, the population had fallen to below 100 individuals. The last reported sighting was by a fisherman in 2009.
The 2016 report concluded that the “key factor responsible for the extirpation of this population was almost certainly ocean inundation,” which resulted in “dramatic habitat loss and perhaps also direct mortality of individuals.” Sea levels around the world have risen by an average 8 inches since the beginning of the 20th century, and are forecast to rise by as many as four additional feet by 2100, according to NASA. Thousands of low-lying atolls in the Pacific and Indian oceans could be left uninhabitable by the mid-century, a recent study found.
In a series of posts to Twitter, Sen. Janet Rice, a member of the Australian Greens party, called the extinction “a huge tragedy” and accused Australian Prime Minister Scott Morrison of turning a blind eye on the species.
“There must be a review of how this happened,” Rice wrote. “No species needs to go extinct. This is a political choice.”
Leeanne Enoch, Queensland’s minister for environment and the Great Barrier Reef, told the Herald that the loss of the species shows that “we are living the real effects of climate change right now.”
“We have consistently called on Scott Morrison and Melissa Price to show leadership on climate change, instead of burying their heads in the sand,” Enoch said. “How many more species do we have to lose for the federal government to take action?”
Along with sea-level rise, drought and extreme weather, climate change is driving the biodiversity crisis that scientists have declared Earth’s sixth mass extinction event. As many as 150 species die off each day. Insect populations around the globe have plummeted, largely as a result of habitat loss and pesticide use. And a 2017 study estimated that 47 percent of mammals and 23 percent of birds on the International Union for Conservation of Nature’s Red List of Threatened Species have been negatively affected by our changing planet.
“The extinction of the Bramble Cay melomys is just the first of what will be countless species lost to climate change if we don’t get our pollution under control,” Noah Greenwald, endangered species director at the Center for Biological Diversity, said in an email Wednesday. “We’re already seeing declines in polar bears and many coral species around the world, and it’s only going to get worse without swift action.”
Nikhil Advani, a lead specialist on climate and wildlife at the World Wildlife Fund, echoed that message.
“We must urgently reduce emissions of greenhouse gases to limit the worst impacts of climate change, while also helping species adapt to a changing climate,” he said in an email.
A dire report late last year from the Intergovernmental Panel on Climate Change, the leading United Nations consortium of researchers studying anthropogenic climate change, makes clear that limiting future warming could prevent scores of species from going extinct in the coming decades.
The IPCC report projects that 6 percent of insects and 8 percent of plants would lose more than half their geographic range with warming of 1.5 degrees Celsius (2.7 degrees Fahrenheit) above pre-industrial levels. Those percentages increase to 18 and 16, respectively, under the 2-degree scenario.
“The Bramble Cay melomys was a little brown rat,” Tim Beshara, federal policy director at The Wilderness Society in Australia, said in a press release. “But it was our little brown rat and it was our responsibility to make sure it persisted. And we failed.”