Satellites See Fishing Industry’s Effects on the High Seas
Until recently, scientists had trouble identifying what was causing large numbers of fish to disappear from the high seas.
Now they have an answer: human beings.
By using emergency signals from ships, scientists got what they are calling the first complete picture of commercial fishing worldwide. And a new study claims the effect is much bigger than researchers thought.
Major commercial fishing covers more than 55 percent of the oceans. The world's fishing fleet travels more than 460 million kilometers a year, according to a study in the journal Science. That is equal to three times the distance between Earth and the sun.
Five countries do 85 percent of high seas fishing. The five are China, Spain, Taiwan (China), Japan and South Korea.
Boris Worm, a marine biologist at Dalhousie University in Canada, called the fishing study "mind-blowing." Worm helped prepare a report on the findings. He likened industrial fishing to factories that are mass producing goods for people around the world.
The latest fishing information was taken from 22 billion ship safety signals sent to satellites orbiting the Earth. Before this, scientists had to use shipping records and observations, which were not always correct.
Ships are obeying no-fishing areas and times, although they do sail along the edges of marine-protected areas. The study noted a drop in fishing around holidays, including Christmas, New Year's and the Lunar New Year.
"The maps of global fishing in this report are sobering," said Douglas McCauley, a marine biologist who wasn't part of the study. He works at the University of California, Santa Barbara.
The top country for fishing is China. Of the 40 million hours that large ships fished in 2016, 17 million hours were by boats sailing under a Chinese flag, noted marine biologist Barbara Block. She is with Stanford University in California.
"No longer is the ocean, especially the high seas – out of sight, out of mind," noted Jane Lubchenco in an email. She formerly led America's National Oceanic and Atmospheric Administration.
Lubchenco was not part of the study.
From 2012 to 2016, the researchers collected signals from boats. New laws require many ships to carry identification systems that every few seconds report their position to satellites as a safety measure.
Scientists then used computer programs to show where the boats were fishing, how they were moving, and what they were likely fishing for and how the fish were caught.
The information was then compared with log books from some ships and they were the same, Worm said. It also shows that in the high seas, there is a heavy use of long line fishing, which catches more of the top predators like tuna, sharks and whales.
Researchers said the findings could be used to better protect the oceans and keep fisheries alive.
Block said that for too long scientists failed to recognize that human activities have the biggest effect on the planet. He added we have to develop a better system or else we'll end up with a planet without Bluefin tuna and some sharks.
I'm Susan Shand.
1.the high seas 公海
He is a self-styled master and pirate captain of the high seas.
2.human activities 人类活动
These animals became extinct because of climate changes and human activities.
3.according to 通过
Prices vary according to the quantity ordered
4.No longer 不再
She no longer feared that they should misunderstand her.
5.That is equal to three times the distance between Earth and the sun.
be equal to 与...相等
Investors can borrow an amount equal to the property's purchase price.
She was determined that she would be equal to any test the corporation put to them.
6."No longer is the ocean, especially the high seas – out of sight, out of mind," noted Jane Lubchenco in an email.
out of mind 心不在焉；发狂
You make no plans and eventually fall out of mind for people.
The end is still unhappy. Out of sight, out of mind, I say.
科学家们利用船只发出的紧急信号获得所谓的“首张全球商业捕捞的完整图片” 。一项新研究表明，其影响远超出了研究人员的预想 。
大型商业捕捞覆盖了超过55%的海域 。据《科学》杂志发表的一项研究显示，全球的捕鱼船队每年航行超过4.6亿公里，相当于太阳到地球距离的三倍 。
加拿大达尔豪斯大学的海洋生物学家鲍里斯·沃姆（Boris Worm）称，这项捕捞研究“令人诧异 。”沃姆协助准备了该报告 。他将工业捕捞喻为全球人民大量生产商品的工厂 。
最新捕捞信息是从220亿条发往绕地运行卫星的船只安全信号中提取的 。在此之前，科学家们只能利用航运记录和观测数据，这些不完全准确 。
尽管船只沿着海洋保护区的边缘航行，但它们都要遵守禁止捕捞区域和时间的规定 。该研究指出，节日期间的捕鱼量有所下降，包括圣诞节、元旦以及春节 。
没有参与这项研究的海洋生物学家道格拉斯·麦考利（Douglas McCauley）表示，“这项报告中的全球捕鱼地图令人警醒 。”他在加州大学圣巴巴拉分校任职 。
其中，捕鱼量最多的国家是中国 。海洋生物学家芭芭拉·布洛克（Barbara Block）指出，2016年，在大型渔船约4000万小时的捕捞时间中，有1700万小时来自于中国船只 。布洛克供职于加州的斯坦福大学 。
简·卢布琴科（Jane Lubchenco）在一封电子邮件中指出，“对人们来说，海洋，尤其是公海，只是眼不见，心不想罢了 。”她曾领导美国国家海洋和大气管理局 。
研究人员收集了从2012年到2016年的船只信号 。新法规要求大量船只携带识别系统，为安全起见，每隔几秒船只会向卫星报告其所处位置 。
沃姆表示，然后他们将这些信息与一些船只的航行日志进行比较，发现数据是一致的 。其还表明，船只在公海上多采用延绳钓，捕捞的大多为金枪鱼、鲨鱼和鲸鱼等顶级肉食动物 。
布洛克表示，长期以来，科学家没有意识到人类活动对地球产生的影响最大 。他补充说，我们必须开发出一个更好的系统，否则，地球上的蓝鳍金枪鱼和一些鲨鱼会绝迹 。