VOA慢速英语2018 随着全球变暖，山地鸟类将会灭绝（在线收听）

 Mountain Birds Will Die Out as Planet Warms

Scientists have recreated a 1985 study of birds in Peru that shows climate change is pushing them from their natural environment.

科学家再现了1985年在秘鲁进行的一项鸟类研究，这次研究表明气候变化正在迫使鸟类离开它们生活的自然环境。

Thirty years ago, researchers studied more than 400 kinds of birds living on a mountainside in Peru.In 2017, researchers looked again at the bird populations.They found that almost all had moved to higher places in the mountain.Almost all had decreased in size.And, the scientists say at least eight bird groups that started at the higher elevations had died out completely.

30年前，研究人员研究了生活在秘鲁山坡上的400多种鸟类。2017年，研究人员再次观察了鸟类的数量。他们发现几乎所有的鸟类都飞到了山上更高的地方。几乎所有鸟类的体型都变小了。并且，科学家们说，至少有8个鸟类种群开始从海拔较高的地区完全灭绝。

John W. Fitzpatrick is director of the Cornell Laboratory of Ornithology and a co-writer of the study.He said, “Once you move up as far as you can go, there’s nowhere else left.”

约翰·W·菲茨帕特里克是康奈尔鸟类学实验室的主任，同时也是这项研究的共同撰稿人。他说，“一旦你向上爬到你能爬的最远的地方，就没有别的地方了。”

The researchers say the birds might have moved up the mountain because of temperature changes.Or, they say, changes to food sources may have forced them to go higher.

研究人员说，由于气温的变化，这些鸟可能已经飞上山了。或者，他们说，食物来源的变化可能迫使他们飞去更高的地方。

The findings were published in the Proceedings of the National Academy of Sciences.

该研究结果发表在了《美国国家科学院院刊》上。 

Past research has documented birds and other animals moving up in elevation in reaction to warming temperatures.Mark Urban is director of the Center of Biological Risk at the University of Connecticut.He said this recent study was the first to prove that rising temperatures and moving to avoid them can lead to extinction.

过去的研究证明鸟类和其他动物向高海拔的地方迁移是对气温升高做出的反应。马克·厄本是康涅狄格大学生物风险中心的主任。他表示，最近的这项研究首次证明了气温上升及为避开高温而向上迁移会导致物种灭绝。

In 1985, Fitzpatrick and a team of scientists established a camp alongside a river running down a mountainside in southeastern Peru.He wanted to document where tropical bird groups there lived.His team spent several weeks using nets to catch and release birds.They kept detailed notes of birds they caught, saw or heard.

1985年，菲茨帕特里克和一个科学家小组在秘鲁东南部一条沿着山坡流淌的河流旁建了一个营地。他想要记录那里热带鸟类种群生活的地方。他的团队花了几个星期的时间用网子捕捉并放飞鸟儿。他们详细记录了他们捉到、看到或听到的鸟类。

In 2016, Fitzpatrick passed his notes, photos and other records to Benjamin Freeman.He is with the Biodiversity Research Centre at the University of British Columbia.Freeman has been researching tropical birds for more than 10 years.He set out in August and September of 2017 to copy Fitzpatrick’s study.His team used the same methods, searching the same places in the same time of year.

2016年，菲茨帕特里克把他的笔记、照片和其他记录交给了本杰明·弗里曼。弗里曼在不列颠哥伦比亚大学生物多样性研究中心工作。他研究热带鸟类已有10余年。他于2017年8月和9月出发仿效菲茨帕特里克的研究。他的团队使用了相同的方法，在一年中同一时间搜寻相同的地方。

Freeman’s team wanted to see how things had changed for the bird groups since 1985.The average temperatures on the mountain had risen 0.42 degrees Celsius.

弗里曼团队想了解自1985年以来鸟类种群的变化情况。山上的平均气温上升了0.42摄氏度。 

Freeman’s team placed 20 sound recording devices on the mountain to record the sounds of birds that might not easily be seen.

弗里曼团队在山上放置了20个录音设备，以记录那些不易被发现的鸟类的声音。 

Freeman said that the birds moved an average of 98 meters further up the mountain.He said he believes that temperature is the main cause of the birds’ movement.

弗里曼表示，这些鸟向山顶平均移动了98米。他说，他认为温度是鸟类迁移的主要原因。 

Fitzpatrick noted that birds used to living in areas with little temperature change may be especially at risk because of climate change.He said, “We should expect that what’s happening on this mountain top is happening more generally in the Andes, and other tropical mountain ranges.”

菲茨帕特里克指出，由于气候变化，习惯生活在气温变化小的地区的鸟类尤其可能面临危险。他说，“我们应该预料到，这个山顶上发生的事情在安第斯山脉和其他热带山脉中会更普遍发生。”

Words in This Story

ornithology – n. the study of birds

extinction – n. the state or situation that results when something (such as a plant or animal species) has died out completely

tropical – adj. of, relating to, occurring in, or used in the tropics

range – n. a series of mountains or hills in a line