Research published in the journal Global Change Biology suggests that the platypus’ cold water loving habits make it vulnerable to climate change. This species’ double-layered fur, which is even finer and denser than that of a polar bear, ensures it stays dry in water that is close to freezing, but may cause it to overheat rapidly when exposed to warm conditions.
Platypus feeling the heat
Researchers at Monash University in Melbourne found that in 60 years one third of the platypus’ habitat could simply become too hot to sustain them.
Using weather and platypus habitat data stretching back more than 100 years, researchers were able to map declines in populations in connection with droughts and heat events. The team then extrapolated their findings across a range of climate change scenarios to model how global warming could affect this unusual native species.
In a worst-case scenario the researchers predicted that the platypus, which is already difficult to spot in the wild, would become extinct on the Australian mainland and confined to Tasmania, King and Kangaroo Islands, three of the coolest parts of the country.
“Platypus have only a limited capacity to moderate their body temperature,” said Professor Jenny Davis from the university’s Australian Centre for Biodiversity, where the research was conducted.
“When summer temperatures become too warm they are very vulnerable. Compared with 50 years ago some places have become too warm for them, their habitat is shrinking.”
An intriguing fraud
When first encountered by European scientists, the platypus was thought to be the fraudulent work of a skilled taxidermist who had sewn a duck’s bill to a mammal’s body. Even after the specimens were found to be authentic, it was some time before scientists concluded that the ‘amphibious mole’ was in fact a mammal, and one of the most evolutionary distinct mammals alive.
It is considered to be one of the most intriguing animals on Earth, but it joins a list of other native Australian wildlife whose future is under threat thanks to the warming planet. Koalas, for example, are suffering as a result of warmer temperatures and increased carbon dioxide in the atmosphere, which is poisoning their main food source, eucalyptus leaves.
Although the platypus is not yet endangered, being classified in Australia as “common but vulnerable”, it is now extinct in the wild in South Australia state, and already appears to be responding to increases in average temperature – certain populations have receded since the 1960s when a warming trend first became evident.
“This is just another piece of evidence that climate change is a real factor affecting our native biodiversity now,” said Dr Ross Thompson, Deputy Director of the Australian Centre for Biodiversity. “It reinforces the need to act decisively on climate change issues.”
Alex Royan, Species Text Author