Recovery of Different Kinds of At-risk Animals Can Raise Conflicts
2022-08-11
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1Wildlife experts in the United States are struggling with a problem:
2As some kinds of threatened animals increase in number, they put pressure on other at-risk creatures.
3Experts say these kinds of situations involve tradeoffs.
4But they do not necessarily show problems with special protection programs or the U.S. Endangered Species Act.
5These tradeoffs show the importance of protecting what some scientists call biological communities, rather than individual species.
6The famous bald eagle's comeback has pressured rare water birds.
7Peregrine falcons are also making a comeback.
8But they threaten the birds called the California least tern and Western snowy plover.
9And, off the California coast, attacks from protected white sharks are hurting the recovery of threatened sea otters.
10Stuart Pimm is with Duke University in North Carolina.
11He is an extinction specialist.
12"Clearly there are occasions when we get these conflicts between species that we're trying to protect," Pimm said.
13"But is it a major worry in conservation? No," he added.
14Conservation means the protection of animals, plants, and natural resources.
15Bruce Stein is a scientist with the National Wildlife Federation.
16Stein suggested that animal recoveries can produce tradeoffs.
17That is because some animals are more adaptable than others to changes in the climate or land.
18Stein said, "A lot of ecosystems where these things are occurring are a little out of whack to begin with because we've altered them in some way."
19He added, "With climate change, there are going to be winners and losers.
20The losers will tend to have specific habitat requirements, narrow ecological niches, and often will be the ones already declining."
21Recovery of America's national bird, the bald eagle, is a success.
22But in one area of Maine, the large bird creates a problem for the only U.S. breeding population of another kind of bird: great cormorants.
23"When they're disturbed by eagles, the adult cormorants will...leave their nests," said Don Lyons, a scientist at the National Audubon Society's Seabird Institute.
24Then gulls, crows, and other birds fly in to eat cormorant eggs and young.
25"If this happens repeatedly, an entire colony can fail," Lyons said.
26Lyons' team organizes volunteers to camp near cormorant gatherings to keep away eagles.
27But conflicts between recovering species and ones still in trouble do not always mean something is wrong, scientists say.
28Such conflicts could be a return to how things were before humans got involved.
29John Fitzpatrick of Cornell University's Laboratory of Ornithology said,
30"When a population gets back to where it's having the same interactions with other organisms as before it went down, that's nature at work."
31Lyons of the Audubon Society said the bald eagle is "challenging our...notions about what's normal" for prey such as great cormorants in New England.
32Cormorants might have been less numerous before eagles declined, he said.
33Lyons noted that the eagle's recovery "complicates the conservation of certain other species."
34But he added that "their recovery is...a welcome complication."
35Relationships between different animals are complex, said Stein of the National Wildlife Federation.
36He said it is often wiser to place effort on protecting and reconnecting habitats to support natural movements.
37I'm John Russell.
1Wildlife experts in the United States are struggling with a problem: As some kinds of threatened animals increase in number, they put pressure on other at-risk creatures. 2Experts say these kinds of situations involve tradeoffs. But they do not necessarily show problems with special protection programs or the U.S. Endangered Species Act. 3These tradeoffs show the importance of protecting what some scientists call biological communities, rather than individual species. 4Winners and losers 5The famous bald eagle's comeback has pressured rare water birds. Peregrine falcons are also making a comeback. But they threaten the birds called the California least tern and Western snowy plover. And, off the California coast, attacks from protected white sharks are hurting the recovery of threatened sea otters. 6Stuart Pimm is with Duke University in North Carolina. He is an extinction specialist. 7"Clearly there are occasions when we get these conflicts between species that we're trying to protect," Pimm said. "But is it a major worry in conservation? No," he added. 8Conservation means the protection of animals, plants, and natural resources. 9Bruce Stein is a scientist with the National Wildlife Federation. 10Stein suggested that animal recoveries can produce tradeoffs. That is because some animals are more adaptable than others to changes in the climate or land. 11Stein said, "A lot of ecosystems where these things are occurring are a little out of whack to begin with because we've altered them in some way." He added, "With climate change, there are going to be winners and losers. The losers will tend to have specific habitat requirements, narrow ecological niches, and often will be the ones already declining." 12Nature at work 13Recovery of America's national bird, the bald eagle, is a success. But in one area of Maine, the large bird creates a problem for the only U.S. breeding population of another kind of bird: great cormorants. 14"When they're disturbed by eagles, the adult cormorants will...leave their nests," said Don Lyons, a scientist at the National Audubon Society's Seabird Institute. 15Then gulls, crows, and other birds fly in to eat cormorant eggs and young. "If this happens repeatedly, an entire colony can fail," Lyons said. 16Lyons' team organizes volunteers to camp near cormorant gatherings to keep away eagles. 17But conflicts between recovering species and ones still in trouble do not always mean something is wrong, scientists say. Such conflicts could be a return to how things were before humans got involved. 18John Fitzpatrick of Cornell University's Laboratory of Ornithology said, "When a population gets back to where it's having the same interactions with other organisms as before it went down, that's nature at work." 19Lyons of the Audubon Society said the bald eagle is "challenging our...notions about what's normal" for prey such as great cormorants in New England. Cormorants might have been less numerous before eagles declined, he said. 20Lyons noted that the eagle's recovery "complicates the conservation of certain other species." But he added that "their recovery is...a welcome complication." 21Relationships between different animals are complex, said Stein of the National Wildlife Federation. He said it is often wiser to place effort on protecting and reconnecting habitats to support natural movements. 22I'm John Russell. 23John Flesher, Christina Larson and Patrick Whittle reported on this story for the Associated Press. John Russell adapted it for VOA Learning English. 24______________________________________________________________________ 25Words in This Story 26tradeoff - n. : a situation in which you must choose between or balance two things that are opposite or cannot be had at the same time - often + between 27species -n. (pl.) a group of animals or plants that are similar and can produce young animals or plants 28extinction - n. : the state or situation that results when something (such as a plant or animal species) has died out completely 29adaptable - adj. able to change or be changed in order to fit or work better in some situation or for some purpose : able to adapt or be adapted 30alter - v. to change (something) 31habitat - n. the place or type of place where a plant or animal naturally or normally lives or grows 32disturb -v. to prevent someone or something from doing what it normally does 33interaction - n. the act of coming together and having an effect on each other - often + with 34notion - n. an idea or opinion 35complicate - v. to make (something) more difficult or less simple 36______________________________________________________________________ 37What do you think of environmental tradeoffs? We want to hear from you. 38We have a new comment system. 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