White-furred animals are in danger of dying out. Climate (天气) change is causing a fall in snow cover, leaving them exposed (暴露的), a new study suggests.
Scientists in Poland have been following the worrying case of the white-coated weasel (白鼬), which sheds (褪去) its brown covering in the winter for a milky coat in order to blend easily into its icy environment.
But researchers have discovered that between 1997 and 2007 the number of days with snow cover was from 80 to 40 in Bialowieza Forest, Poland. It means that the little animals are caught out in a completely unsuitable environment, where they can be caught by foxes and crows. Scientists found that on days when there was little winter snow cover. The number of white-coated weasels they managed to catch fell to as low as 20 percent of the total. It meant that the rest had been killed.
The problem is likely to affect other white-furred animals such as the Arctic fox when the snow cover increasingly gives way to a landscape (风景) of greens and browns.
In the near future white weasels may disappear completely from many areas of Northern Europe and America. They will either be replaced by brown ones or they will evolve (进化).
Researchers also carried out tests using toys of brown and white-coated weasels to see if the colors were actually making a difference to predators (捕食者). They found lots of animals had come near to the white toys, but none had shown interest in the brown toys.
The researchers are hopeful the animals will learn to adapt (适应), but say they cannot rule outthe animals disappearing completely.
