It wasn’t especially charismatic, just a small rodent, scurrying around on an extremely limited patch of habitat on a low-lying island on the surface of the Great Barrier Reef. Yet the disappearance of the Australian Bramble Cay melomys made headlines this summer—because scientists deemed the critter, also known as the mosaic-tailed rat, to be the first mammal to go extinct as a result of manmade climate change.

The rat had no defenses against the impacts of sea-level rise. Researchers concluded that it perished because the tiny island was inundated on multiple occasions.

Its demise is a snapshot of a growing problem. According to a study published last year in the journal Science, one in six species worldwide could face extinction if climate change proceeds as expected.

In an interview with National Geographic, renowned biologist E.O. Wilson explained why. It all comes down to habitat loss:

“Changing climatic conditions destroys habitat wholesale. There are parts of the Earth where, as habitats are affected, the fauna and flora have no way to retreat. Parts of the world will see very large extinction of species and habitat because of climate warming. The Arctic and subarctic regions, for instance, contain a rich fauna and flora and those are in imminent danger.”

“Changing climatic conditions destroys habitat wholesale. There are parts of the Earth where, as habitats are affected, the fauna and flora have no way to retreat. Parts of the world will see very large extinction of species and habitat because of climate warming. The Arctic and subarctic regions, for instance, contain a rich fauna and flora and those are in imminent danger.”

Think of an animal threatened by the impacts of climate change, and chances are the iconic polar bear will come to mind. The marine mammal depends on sea-ice for survival. Disappearing ice sheets interfere with the bears’ traditional feeding patterns, putting them into desperate circumstances as their habitat literally melts.  But the problem of vanishing sea-ice will only get worse if climate change continues unchecked.

In Earthjustice’s Alaska offices, attorneys Eric Jorgensen and Erik Grafe are challenging proposed federal plans to sell leases for new offshore oil and gas drilling. They know it will only result in the release of more greenhouse gas emissions into the atmosphere (to the tune of 850 million metric tons, according to a study by Greenpeace and Oil Change International), contributing to runaway climate change that is fundamentally altering the climate. On a global scale, this will ultimately bring consequences not only for the polar bear, but potentially thousands more species ranging from coral, to Antarctic penguins, to rainforest amphibians facing threats that are exacerbated by climate change.

It gets worse when you consider how often politics, and not science, become the driving factor in all-important decisions on listing species for federal protection under the Endangered Species Act.

Case in point: wolverines.

No, not the mutant of Marvel Comics fame, but the fierce mammal of the Northern Rockies—which cannot survive without snow. As Doug Chadwick, author of The Wolverine Way, explained to Earthjustice in an interview:

“Females require deep, persistent snowpack to raise their young from February through May, and they don’t tend to tolerate warm temperatures very well. As scientists model various climate regimes, they have predicted that wolverines are going to lose perhaps a third of their existing range in the U.S. by 2050.”

In Bozeman, Montana, Earthjustice attorney Tim Preso has fought for years to get the wolverine listed for protection under the Endangered Species Act. The U.S. Fish & Wildlife Service initially declined to list the badger-like creature for protection, even though it could easily serve as the Northern Rockies’ poster child for a species directly threatened by climate change. This past spring, a federal judge rejected that listing decision as illegal. He slammed the service for ignoring the warning signs of climate change, and for buckling to political pressure from Western states in declining to list it:

“The wolverine’s sensitivity to climate change, in general, cannot really be questioned.”

“The wolverine’s sensitivity to climate change, in general, cannot really be questioned.”

The judge also noted that reasons having nothing to do with science, and everything to do with politics, may have been a factor in the agency’s decision. He said, “Internal service documents expose the likely motives—freedom from perceived federal oversight, maintaining the public’s right to trap—behind the states’ efforts against listing the wolverine.”

For species that have already been pushed to the brink for other reasons, climate change can be the last straw.

This past May in the Pacific Northwest, a federal district court threw out federal agencies’ fifth try at crafting a legal and scientifically sound plan that adequately protects endangered salmon runs in the Columbia and Snake rivers. Earthjustice attorneys Todd True and Steve Mashuda have been advocating for years for a scientifically sound approach for protecting these iconic salmon runs.

The fish need cold water—think rivers that start in the mountains as snow melt —to survive. Adult salmon’s natural migration patterns normally carry them from the Pacific Ocean to some of the coldest high-elevation rivers of Idaho, where the best available spawning grounds are located. But their path is impeded by a series of federal dams that were constructed along the migratory route.

Rivers that once flowed undammed have been converted into slack-water reservoirs. Hotter-than-average weather leaves these pools baking in the sun, and in recent years these conditions have further imperiled the fish, exposing them to dangerously warm waters. Last summer, tens of thousands of adult salmon died off due to record-high river temperatures.

The impact of climate change on salmon wasn’t lost on the federal judge reviewing the agency plan. He blasted federal regulators for not taking this factor seriously enough. Judge Michael Simon wrote: “NOAA Fisheries’ analysis does not apply the best available science, overlooks important aspects of the problem, and fails properly to analyze the effects of climate change.”

These days, global average temperatures are consistently entering new record-breaking territory (it got so hot in India this summer that people’s shoes were melting onto roads). At the same time, there’s more data at our fingertips than ever before about the connection between climate change and the latest wave of extinction.

The Endangered Species Act serves as our nation’s best defense against the global extinction crisis.  Now more than ever we need this and our other bedrock environmental laws to be fully funded and enforced by Congress and our government agencies.