（带文稿）1029 思考一个悖论：是否该为了救动物A而牺牲B（文末小测）

Transcript

    Since ancient times, owls have been called many things, such as mysterious. These birds can be found in many parts of the world. And today, one kind of owl is causing a problem in forests of the northwestern United States.

    Barred owls are a large species native to eastern North America, but they began moving west at the start of the 20th century. By 1973, large numbers of barred owls had arrived in the western state of Washington. Later they moved south into Oregon and California.

    In parts of the Pacific Northwest, the owls are now believed to be causing a drop in the population of a smaller, less aggressive bird: the northern spotted owl.

    In many ways, the barred owl is the spotted owl’s worst enemy. The barred owl has more babies per year and eats the same animals, like squirrels and wood rats. And their numbers are now larger in many parts of the spotted owl’s traditional territory.

In this photo taken in the early morning hours of Oct. 24, 2018, wildlife technician Jordan Hazan records data in a lab in Corvallis, Ore., from a male barred owl he killed earlier in the night.

    David Wiens is a biologist with the U.S. Geological Survey, a federal agency that studies the Earth and its natural resources. He and other officials are doing something unusual to protect spotted owls: killing barred owls.

    It is a controversial, experimental program. More than 2,400 barred owls have already been shot.

    Wiens is the son of a well-known bird expert and grew up with a fascination for birds. He has mixed feelings about the program.

    “It’s a little distasteful, I think, to go out killing owls to save another owl species,” he says. But he adds, “We knew that barred owls were outcompeting spotted owls and their numbers were growing too fast."

    To catch barred owls, officials put digital bird callers on the ground. Then they step back and wait as several sounds from the devices fill the air. All of this happens in the dark of night.

    Barred owls dislike other birds in their territory, so they will fly down and chase other owls out. That is when Wiens and his team try to shoot them.

This image shows the differences between a barred owl and northern spotted owl.

    The federal government has been trying for years to save the northern spotted owl. Some years ago, this bird was at the center of a huge battle over logging rights across Washington, Oregon and California.

    In 1990, the northern spotted owl was listed as threatened under the Endangered Species Act, and appeared on the cover of Time magazine. Then, officials suspended logging on millions of hectares of forests to protect the bird. But the spotted owl population continued to fall.

    During that time, researchers began to study another threat: Larger, more aggressive barred owls were competing with spotted owls for food and space and pushing them out of some areas.

    Now comes this final effort to see whether the government can save spotted owls.

    The U.S. Fish and Wildlife Service launched the experiment a few years ago. It has raised questions, such as: How much is it possible to reverse a drop in population that has been happening for years, caused in part by human activity? And, as climate change continues to push species out and affect how and where plants and animals live, how much should people get involved?

In this photo taken in the early morning hours of Oct. 24, 2018, wildlife technician Jordan Hazan records data in a lab in Corvallis, Ore., from a male barred owl he killed earlier in the night.

    Just as with other conservation measures that involve killing one animal to save another, the program has also led to legal questions and debate. Still the Fish and Wildlife Service has a permit to kill up to 3,600 owls and, if the program works, could decide to expand its efforts.

    In four small study areas in Washington, Oregon and California, Wiens and his team have been killing barred owls to see whether the native birds return to their land once their competitors are gone. Small efforts to remove barred owls in northern California and Canada’s British Columbia have shown promising results.

    Wiens now sees his gun as a research tool. He said that, by getting involved, humans “may be able to achieve more biodiversity in the environment, rather than just having barred owls take over and wipe out all the prey species.”

    But not everyone agrees.

    Marc Bekoff is a professor of ecology and biology at the University of Colorado, Boulder. He strongly opposes the experiment and says humans should find another way to help owls. Bekoff notes that there is no way to see it as a good thing “if you’re killing one species to save another.”

    Michael Harris directs the wildlife law program for Friends of Animals, a nonprofit group. He thinks the government should direct its attention on what humans are doing to the environment and protect habitats rather than blaming barred owls.

    Some Americans see a responsibility to get involved. They note that humans are to blame for activities like logging, which helped lead to the drop in spotted owl numbers. But other people just see a losing situation.

    “A decision not to kill the barred owl is a decision to let the spotted owl go extinct,” said Bob Sallinger. He is conservation director with the nonprofit Audubon Society in Portland, Oregon.

    If reducing the barred owl population improves the number of spotted owls, the U.S. Fish and Wildlife may consider killing more barred owls as part of a longer-term effort. Enough success has been noted that the experiment already has been extended to August of 2021.

    I’m Dorothy Gundy. And I’m Bryan Lynn.

QUIZ【答案在Words in This Story 最下方】

Why are barred owls affecting spotted owl numbers in some northwestern forests?

A.They are bigger and can be hostile toward spotted owls.

B.Barred owls have more babies each year than spotted owls.

C.They are eating up the animals spotted owls need for food.

D.Barred owls are affecting spotted owls for all these reasons.

How do Wiens and other officials catch the barred owls?

A.They use equipment to climb trees at night and shoot the owls.

B.Officials use a special device that makes bird calling sounds.

C.They put barred owl food in traps and the owls fly into them.

D.Officials capture barred owls through all of these methods.

Words in This Story

controversial – adj. relating to or causing much discussion, disagreement or argument

fascination – n. the act of being very interested in something or someone

logging – n. to cut down trees in an area for wood

reverse – v. to move backward; to make something the opposite of what it was

conservation – n. the protection of animals, plants and natural resources

wipe out – v. to kill or destroy someone or something completely

ecology – n. the field of biology that deals with the relationship of organisms to one another to their environment

【DBBD】