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A new study published in the Journal of Applied Ecology revealed when, where and how most songbirds migrate offshore over North American coasts. This data can help wind energy managers cut down on birds dying from hitting wind turbines(涡轮机)while generating sustainable energy.
The researchers studied 10 years of weather radar data from 16 sites and found that birds flying over the Atlantic Coast and the Gulf of Mexico gather more closely and move for a shorter time than those flying over land. More birds also migrate in fall than in spring. Shannon Curley the study's lead researcher, explained, “Birds migrate over the sea on fewer nights than over land.There's no place to rest and refuel on the water, so birds may wait for ideal atmospheric conditions,such as favorable winds, before making an offshore crossing."
This short yet critical time window gives wind energy managers a chance to reduce collisions (相撞). Curley said they could pause turbine work on nights when migration is most intense - a practice that is currently more common in Europe than North America. “These peak nights of migration tend to have fairly nice weather and calmer winds, and are therefore not the nights when wind operators have a huge energy harvest,” Curley noted. “So there might be a sweet spot where we can target these big migration nights and give these birds safe passage."
The study also found that songbirds migrating offshore fly at lower altitudes than those migrating over land, potentially putting them at greater risk of wind turbine collisions. The U.S.Fish and Wildlife Service says 140.000 to 327.000 birds die from land turbines each year. But no one knows how many die from offshore turbines, since dead birds’ bodies wash away easily. So using radar technology to identify high-risk areas is key.
With one-third of all American bird species rapidly declining, data-driven decisions abou turbine siting and operations can point the way to sustainable energy while also saving birds. “Our hope is that this work will help identify high-risk, high-use areas for birds and contribute to positive green energy solutions," Curley said.
4. What can we learn about the songbirds in paragraph 2?
A. They favor flying over open seas.
B. They become more active on spring nights.
C. They are particular about where to rest.
D. They time crossings by weather conditions.
5. What does the underlined phrase “'a sweet spot" refer to?
A. An ideal balance.
B. A moral dilemma.
C. An opportunity for profit.
D. A place without turbines.
6. Why is it diffcult to identify high-risk areas offshore?
A. Birds change their travelling routes.
B. Wind strength at sea is unpredictable.
C. Dead birds’ bodies are hard to trace.
D. Radar technology is underdeveloped
7. What is the main idea ofthe passage?(有改动)
A. Radar changes songbird migration study.
B. Study balances energy and bird protection.
C. North America tests-smart wind practices
D. Offshore turbines kill more kinds than land ones.
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