Polar Bears in Greenland Might Have Found Place to Survive
2022-06-21
LRC
TXT
大字
小字
滚动
全页
1As polar bears fight for survival because of disappearing Arctic sea ice, a new group of Greenland bears seems to have found an icy area that might permit a small population to "hang on."
2But the situation overall for the endangered polar bear species remains serious.
3Scientists say the animals are in danger of disappearing because of the effects of climate change.
4A team of scientists recently studied a group of a few hundred polar bears in Southeast Greenland.
5These bears are genetically different and geographically separate from others.
6What is unusual about these bears is that they survive even while having just 100 days a year when there is enough sea ice to hunt seals.
7In other places, polar bears need at least 180 days, usually more, of sea ice for them to effectively hunt.
8When there is no sea ice, bears often do not eat for months.
9Sea ice is frozen ocean water. With limited amounts of this ice, the Southeast Greenland polar bears use freshwater ice masses called icebergs.
10The icebergs - created from the shrinking Greenland ice sheet - serve as hunting grounds, scientists say.
11A study on the new finding recently appeared in the publication Science.
12The scientists, however, are not sure if the bears might be surviving because they are smaller and have fewer babies than other polar bear populations.
13Kristin Laidre was the lead writer of the study. Over nine years, Laidre followed, studied and tested the all-white bears - usually from a helicopter.
14"These polar bears are adapted to living in an environment that looks like the future," Laidre said.
15But Laidre added that Greenland is special.
16"Most bears in the Arctic don't have glacial ice," she said.
17Laidre explained, "We project large declines of polar bears across the Arctic and this study does not change that very important message."
18The population of polar bears is on the southeast part of Greenland, where there are no towns.
19For years scientists believed these bears were part of the same population that existed in Northeast Greenland.
20But they are not, Laidre said. Wind and other conditions around 64 degrees North make it next to impossible for bears to move north of that point, she added.
21While most bears travel 40 kilometers over four days, the Southeast Greenland bears go about 10 kilometers in the same amount of time, the study found.
22"They just stay in the same place for years and years," Laidre said.
23Beth Shapiro was the co-writer of the study.
24She said genetic testing has shown that the Southeast Greenland bears are different from other polar bear populations.
25In general, the Southeast Greenland bears are thinner than other Arctic bears, with females weighing about 185 kilograms.
26This compares to weights of about 199 to 255 kilograms for bears in other parts of the North American Arctic, Laidre said.
27The Southeast Greenland bears also often have fewer babies, she added.
28This could be because they are so isolated and do not get as many chances to reproduce.
29"They're not reproducing as much as other individuals... They're not as healthy as other individuals who are in a better habitat," Shapiro said.
30She used the term oasis - meaning a safe place that is surrounded by something unpleasant - to describe where the bears live.
31"So it's kind of an oasis maybe, but it's not a happy oasis," Shapiro said.
32"It's a I'm-struggling-to-get-by-but-just-making-it kind of oasis."
33I'm John Russell.
1As polar bears fight for survival because of disappearing Arctic sea ice, a new group of Greenland bears seems to have found an icy area that might permit a small population to "hang on." 2But the situation overall for the endangered polar bear species remains serious. Scientists say the animals are in danger of disappearing because of the effects of climate change. 3A team of scientists recently studied a group of a few hundred polar bears in Southeast Greenland. These bears are genetically different and geographically separate from others. 4What is unusual about these bears is that they survive even while having just 100 days a year when there is enough sea ice to hunt seals. In other places, polar bears need at least 180 days, usually more, of sea ice for them to effectively hunt. When there is no sea ice, bears often do not eat for months. 5Sea ice is frozen ocean water. With limited amounts of this ice, the Southeast Greenland polar bears use freshwater ice masses called icebergs. The icebergs - created from the shrinking Greenland ice sheet - serve as hunting grounds, scientists say. 6A study on the new finding recently appeared in the publication Science. 7The scientists, however, are not sure if the bears might be surviving because they are smaller and have fewer babies than other polar bear populations. 8Kristin Laidre was the lead writer of the study. Over nine years, Laidre followed, studied and tested the all-white bears - usually from a helicopter. 9"These polar bears are adapted to living in an environment that looks like the future," Laidre said. 10But Laidre added that Greenland is special. "Most bears in the Arctic don't have glacial ice," she said. 11Laidre explained, "We project large declines of polar bears across the Arctic and this study does not change that very important message." 12The population of polar bears is on the southeast part of Greenland, where there are no towns. For years scientists believed these bears were part of the same population that existed in Northeast Greenland. 13But they are not, Laidre said. Wind and other conditions around 64 degrees North make it next to impossible for bears to move north of that point, she added. 14While most bears travel 40 kilometers over four days, the Southeast Greenland bears go about 10 kilometers in the same amount of time, the study found. 15"They just stay in the same place for years and years," Laidre said. 16Beth Shapiro was the co-writer of the study. She said genetic testing has shown that the Southeast Greenland bears are different from other polar bear populations. 17In general, the Southeast Greenland bears are thinner than other Arctic bears, with females weighing about 185 kilograms. This compares to weights of about 199 to 255 kilograms for bears in other parts of the North American Arctic, Laidre said. 18The Southeast Greenland bears also often have fewer babies, she added. This could be because they are so isolated and do not get as many chances to reproduce. 19"They're not reproducing as much as other individuals... They're not as healthy as other individuals who are in a better habitat," Shapiro said. 20She used the term oasis - meaning a safe place that is surrounded by something unpleasant - to describe where the bears live. 21"So it's kind of an oasis maybe, but it's not a happy oasis," Shapiro said. "It's a I'm-struggling-to-get-by-but-just-making-it kind of oasis." 22I'm John Russell. 23Seth Borenstein reported on this story for the Associated Press. John Russell adapted it for VOA Learning English. 24__________________________________________________________________ 25Words in This Story 26hang on - phr v. to barely keep surviving 27ice sheet - n. a permanent layer of ice covering a large area of land, especially a polar region 28species - n. biology : a group of animals or plants that are similar and can produce young animals or plants : a group of related animals or plants that is smaller than a genus 29adapt - v. to change (something) so that it functions better or is better suited for a purpose 30isolate - v. to put of keep someone or something in a place or situation that is separate from others 31habitat - n. the place or type of place where a plant or animal naturally or normally lives or grows