英语听力：自然百科 Mystery Pelican Die-off in Calif 神秘的塘鹅死亡事件-英语课

时间：2018-12-03 作者：英语课 分类：自然百科2008年

英语课

Wild life experts are trying to figure out why sick, disoriented and bruised 2 California brown pelicans 4 are being found in record numbers up and down the west coast of North America.

The birds, some of them dead, have been spotted 5 from Washington State, to Baja California in Mexico.

"People are finding them in unusual places, and they are finding these birds are landing in the middle of the roads--some of them are getting hit by cars. There have been reports of birds landing in people’s backyards, which is very unusual behavior for these birds."

The pelican 3 started appearing late last month in Southern California. The International Bird Rescue Research Center has received dozens of birds at two Californian facilities.

"They are coming in very thin and bit disoriented, usually hypothermic. "

They also have bruise 1 inside their pouches 6 and many of the birds' feet have been swollen 7. Typically, this time of the year there is a significant die-off of young brown pelicans. But marine 8 biologists say they are seeing a larger-than-normal die-off of adults, and some researchers suspect the corporate 9 is a naturally occuring toxin 10 found in algae 11.

"In this particular area over the last three to four years, we’ve seen a regular occurrence, typically in the spring, of a particular group of alga that's capable of producing a very powerful neurotoxin called 'domoic acid'. Through the consumption of those algae, it gets into food chains, into small fishes such as anchovies 12 and sardines 13 and any organism alike. A pelican eating that material can acquire enough of it that it actually causes neurological distress 14 or even death. "

While disorientation is a common symptom among birds poisoned by domoic acid, the pelican’s other symptoms don’t fit their profile. So far, there are no concrete answers. Meanwhile, volunteers are nursing the feather patients.

"We are providing them with IV fluids, oral fluids, food, medication if necessary, and getting them eating on their own. "

The California brown pelican is a sub-species of the brown pelican. Over-hunting and DDT poisoning caused brown pelican populations to plummet 15 during the first half of the 20th century. And by the early 1970s the birds were all but gone. After DDT was banned in the US in 1972, the species made a dramatic comeback.

1 bruise

n.青肿，挫伤；伤痕；vt.打青；挫伤

The bruise was caused by a kick.这伤痕是脚踢的。
Jack fell down yesterday and got a big bruise on his face.杰克昨天摔了一跤，脸上摔出老大一块淤斑。

2 bruised

[医]青肿的，瘀紫的

his bruised and bloodied nose 他沾满血的青肿的鼻子
She had slipped and badly bruised her face. 她滑了一跤，摔得鼻青脸肿。

3 pelican

n.鹈鹕，伽蓝鸟

The pelican has a very useful beak.鹈鹕有一张非常有用的嘴。
This pelican is expected to fully recover.这只鹈鹕不久就能痊愈。

4 pelicans

n.鹈鹕( pelican的名词复数 )

Kurt watched the Pelicans fire their jets and scorch the grass. 库尔特看着鹈鹕运兵船点火，它们的喷焰把草烧焦。来自互联网
The Pelican Feeding Officers present an educational talk while feeding the pelicans. 那个正在喂鹈鹕的工作人员会边喂鹈鹕边给它上一节教育课。来自互联网

5 spotted

adj.有斑点的，斑纹的，弄污了的

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。

6 pouches

n.（放在衣袋里或连在腰带上的）小袋( pouch的名词复数 )；（袋鼠等的）育儿袋；邮袋；（某些动物贮存食物的）颊袋