科学美国人60秒 SSS Migrating Birds Prefer Lakefront Property
时间：2018-12-02 作者：英语课 分类：2016年Scientific American(十二)月
You may have spotted 1 V-shaped squadrons of geese heading south this fall. But for many migrants—like smaller songbirds—nighttime is the right time, when it comes to migration 2. Winds are gentler. And darkness helps them avoid airborne attacks. Of course darkness also makes it harder for us to see them. Which is where weather radar 3 comes in.
"These radars 4 were designed to detect water drops in the air, precipitation in the air." Jeff Buler, an ornithologist 5 and aeroecologist at the University of Delaware. "They also detect any other large object that will reflect back radio energy. It essentially 6 sees insects and bats and birds as large drops of water."
Buler and his team used three weather surveillance radars to track migratory 7 birds near the Great Lakes—observing four spring migrations 8 in a row. And what they found was, as the night migration ended, and dawn broke, many birds in flight over the lakes turned back. Decided 9 to quit for the day. Which meant crowded real estate on the south shore of the lakes, as the birds piled up there to wait out the day. The study is in the journal The Auk. [Kevin M. Archibald et al., Migrating birds reorient toward land at dawn over the Great Lakes, USA]
The message for conservators? "Restoring one hectare of forest along the shoreline of Lake Michigan might be able to support more migrants than a hectare of forest 50 km away from the shoreline." Because birds—just like humans—like that lakefront property.
—Christopher Intagliata
[The above text is a transcript 10 of this podcast.]
- The milkman selected the spotted cows,from among a herd of two hundred.牛奶商从一群200头牛中选出有斑点的牛。
- Sam's shop stocks short spotted socks.山姆的商店屯积了有斑点的短袜。
- Swallows begin their migration south in autumn.燕子在秋季开始向南方迁移。
- He described the vernal migration of birds in detail.他详细地描述了鸟的春季移居。
- They are following the flight of an aircraft by radar.他们正在用雷达追踪一架飞机的飞行。
- Enemy ships were detected on the radar.敌舰的影像已显现在雷达上。
- Servos for large radars and launchers are either electro-hydraulic or all-electric. 大型雷达和发射装置的伺服系统，不是电动-液压式的，就是全电动式的。 来自辞典例句
- Range-velocity simultaneous pull-off is one of effective measures for countering PD radars. 距离-速度同步拖引干扰是对抗PD雷达的有效方法。 来自互联网
- That area is an ornithologist's paradise.那个地区是鸟类学家的天堂。
- Now I know how an ornithologist feels.现在我知道做为一个鸟类学家的感受了。
- 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。
- Many migratory birds visit this lake annually.许多候鸟每年到这个湖上作短期逗留。
- This does not negate the idea of migratory aptitude.这并没有否定迁移能力这一概念。
- It foundered during the turmoils accompanying the Great Migrations. 它在随着民族大迁徙而出现的混乱中崩溃。 来自辞典例句
- Birds also have built-in timepieces which send them off on fall and spring migrations. 鸟类也有天生的时间感应器指导它们秋春迁移。 来自互联网
- This gave them a decided advantage over their opponents.这使他们比对手具有明显的优势。
- There is a decided difference between British and Chinese way of greeting.英国人和中国人打招呼的方式有很明显的区别。
- A transcript of the tapes was presented as evidence in court.一份录音带的文字本作为证据被呈交法庭。
- They wouldn't let me have a transcript of the interview.他们拒绝给我一份采访的文字整理稿。