Platypuses Lost 22% of Their Habitat Over Last 30 Years

One of Australia’s most adored animal oddities is under threat, reports Lisa Cox for the Guardian. A new report estimates that the platypus has disappeared from at least 22 percent of its former habitat over the past three decades, and recommends the duck-billed, egg-laying mammal be added to the country’s list of threatened species. The loss is equivalent to platypuses disappearing from an area larger than the entire state of Washington.

This formal assessment, a collaboration between researchers with the University of New South Wales, the Australian Conservation Foundation, the World Wildlife Foundation and the Humane Society, calls for Australia to classify the species as nationally threatened. The assessment echoes troubling findings reported earlier this year, which projected that the platypus population could decline between 47 and 66 percent by 2070.

Internationally, platypuses are listed as “near threatened” by the International Union for Conservation of Nature’s (IUCN). The new report recommends that the severity of the species’ listing be increased to “vulnerable” to respond to evidence of past and projected future declines in the platypus population.

Only found in Australia, platypuses inhabit rivers and streams on the country’s eastern seaboard from Queensland to Victoria and across much of Tasmania. Despite being warm blooded, furry and nursing their young with milk, the platypus lays eggs, making it—along with the two types of echidna—one of just three known species of monotreme on Earth. Combined with their appearance, these traits would be plenty to make the platypus a truly singular animal, but the details of their physiology only make them stranger and more fascinating.

For starters, their signature duck-shaped bill is fleshy rather than hard like a bird’s and can detect electromagnetic fields underwater, which helps the platypus find food in murky waters. Males have a venomous spur on their hind legs, and females lactate by sweating on their tummies. Recent research has even revealed that they glow turquoise under ultraviolet light.

But this uniquely Australian creature’s riverine habitat is being threatened by climate change, in the form of more severe and more frequent droughts, as well as by water diversion and extraction. Other threats mentioned by the report include land clearing, pollution and predation by feral dogs and foxes, reports Michael Slezak for Australia’s ABC News.

"Protecting the platypus and the rivers it relies on must be a national priority for one of the world's most iconic animals," says Richard Kingsford, an ecologist at the University of New South Wales and the report’s lead author, in a statement. "There is a real concern that platypus populations will disappear from some of our rivers without returning, if rivers keep degrading with droughts and dams."

The declines quantified by the report were most severe in New South Wales, which saw a 32 percent drop in platypus observations since 1990, followed by Queensland with a 27 percent decline and Victoria decreasing by 7 percent, per a statement. Some urban areas were even worse. In some places near Melbourne, for example, the decline in observations was as high as 65 percent.

“We have a national and international responsibility to look after this unique animal and the signs are not good” says Kingsford in the statement. "Platypus are declining and we need to do something about threats to the species before it is too late."

Alex Fox | | READ MORE

Alex Fox is a freelance science journalist based in California. He has written for the New York Times, National Geographic, Science, Nature and other outlets. You can find him at Alexfoxscience.com.