Scientists in Poland have been following the worrying case of the white-coated weasel, which sheds its tawny covering in the winter for a milky coat allowing it to blend effortlessly into its icy environment.
It means that the little creatures are being caught out in a completely unsuitable environment, where they are easy prey for predators like foxes and crows.
The team at the Polish Academy of Sciences found that on days when there was little winter snow cover, the number of white-coated weasels they managed to capture fell to as low as 20 percent of the total, suggesting the rest had been killed.
Previously they would have been dominant, because their coats would have given them a survival advantage.
The problem is likely to affect other white-furred mammals and birds living in areas vulnerable to climate change such as the Arctic fox as the snow cover increasingly gives way to a landscape of greens and browns.
Scientists have recorded 21 mammal and bird species which turn white in the winter to hide themselves in snowy landscapes including the mountain hare, the Siberian hamster, the collared lemming, the white-tailed jackrabbit and the willow ptarmigan bird.
“According to studies on showshoe hares during periods when hares are colour mismatched weekly survival probability decreases by 3.3 - 6.5 percent. This seems not to be a big effect, but the cumulative effect over winter can seriously influence mortality of the species.
The authors say both findings suggest that the decrease in white-coated weasels is due to an increase in detection by predators in a less snowy environment.
The researchers are hopeful the animals will learn to adapt, but say they cannot rule out the animals vanishing entirely.
Weasels that do not change colour in the winter, are more likely to survive to pass on their brown-coated genes, increasing the numbers of the darker species.
Dr Zub added: “We should not underestimate the power of natural selection. We hope that along with future climate warming, autumn temperatures will also increase, providing an additional signal to the weasels to delay their moult.