2018年CRI Polar bears starve as Arctic sea ice melts
时间：2018-12-24 作者：英语课 分类：2018CRI中国国际广播电台
A new study has found that the Arctic's iconic polar bears are finding it harder to hunt for food due to melting sea ice caused by climate change, putting the species at a growing risk of extinction 1.
Researchers from the United States Geological Survey used high-tech 2 collars to track nine female polar bears for periods of 10 days over three consecutive 3 years.
The study found that polar bears have higher metabolism 4 than previously 5 thought.
About half of the bears under observation lost ten percent or more of their body weight.
"They have to capture at least one seal every five to 10 days, that's just to break even. And if they don't do that they are going to lose weight and if they lose weight then there are other things that come into play with their health, their ability to reproduce and so forth," said George Durner, a co-author of the new study.
The Arctic predator 6 needs sea ice to move around and find spots where they can catch prey 7.
But because of climate change, sea ice in the region is melting at a rate of 14 per cent per decade, which forces the bears to travel further and use more energy for their hunts.
"If we cut that period short, say the sea ice melt occurs earlier in the summer, then we are essentially 8 pulling the rug out from underneath 9 the polar bears and they don't have that platform any longer to capture seals," said Durner.
According to the National Snow & Ice Data Center, Arctic sea ice in December last year was at its second-lowest level since 1979.
If this trend continues, it could mean smaller bears and fewer cubs 10 for a species that is already endangered.
"Things are likely to get worse before they're going to get better and if it's bad for polar bears it might be affecting us in other ways, us being humans in other ways," said Durner.
The population of polar bears is currently sitting at around 20-thousand.
Researchers estimate that the figure has declined by 40 percent over the past decade.
- The plant is now in danger of extinction.这种植物现在有绝种的危险。
- The island's way of life is doomed to extinction.这个岛上的生活方式注定要消失。
- The economy is in the upswing which makes high-tech services in more demand too.经济在蓬勃发展，这就使对高科技服务的需求量也在加大。
- The quest of a cure for disease with high-tech has never ceased. 人们希望运用高科技治疗疾病的追求从未停止过。
- It has rained for four consecutive days.已连续下了四天雨。
- The policy of our Party is consecutive.我党的政策始终如一。
- After years of dieting,Carol's metabolism was completely out of whack.经过数年的节食，卡罗尔的新陈代谢完全紊乱了。
- All living matter undergoes a process of metabolism.生物都有新陈代谢。
- The bicycle tyre blew out at a previously damaged point.自行车胎在以前损坏过的地方又爆开了。
- Let me digress for a moment and explain what had happened previously.让我岔开一会儿，解释原先发生了什么。
- The final part of this chapter was devoted to a brief summary of predator species.本章最后部分简要总结了食肉动物。
- Komodo dragon is the largest living lizard and a fearsome predator.科摩多龙是目前存在的最大蜥蜴，它是一种令人恐惧的捕食性动物。
- Stronger animals prey on weaker ones.弱肉强食。
- The lion was hunting for its prey.狮子在寻找猎物。
- Really great men are essentially modest.真正的伟人大都很谦虚。
- She is an essentially selfish person.她本质上是个自私自利的人。
- Working underneath the car is always a messy job.在汽车底下工作是件脏活。
- She wore a coat with a dress underneath.她穿着一件大衣，里面套着一条连衣裙。