为什么选择吃鱼可能会杀死鲨鱼

为什么选择吃鱼可能会杀死鲨鱼

The ideal shark hotspot in the ocean is rich in appealing food -- and that's exactly where commercial fishing vessels are snagging sharks along with the fish they catch, according to a new study.

一项新的研究表明，海洋中理想的鲨鱼聚集地富含诱人的食物，而这正是商业渔船捕获鲨鱼和鱼的地方。

An international team of researchers spanning 26 countries tracked about 2.000 sharks using satellite tags to determine areas in the ocean where multiple shark species converged. They were found in ocean frontal zones, which act as the boundaries between different water masses. Nutrients and plankton flourish here, which encourages fish to flock to the zones.

一个由26个国家组成的国际研究小组使用卫星标签跟踪了大约2000条鲨鱼，以确定海洋中多种鲨鱼聚集的区域。它们发现于海洋锋面区域，作为不同水团之间的边界。营养物质和浮游生物在这里繁衍生息，这促使鱼类向这些区域聚集。

While this feeding ground draws sharks, it also draws commercial longline fishing vessels. This method include hundreds of baited hooks hanging from a single line used to catch swordfish, tuna and halibut. But they also catch dolphins, sea turtles, birds and sharks.

这片觅食地吸引鲨鱼的同时，也吸引了商业长线钓渔船。这种方法包括数百个带饵料的鱼钩挂在一条钓线上，用来钓旗鱼、金枪鱼和比目鱼。但它们也捕捉海豚、海龟、鸟类和鲨鱼。

The movement data of the sharks helped the researchers determine that one quarter of the sharks' habitats were also located in active fishing areas. The study published July 25 in the journal Nature.

这些鲨鱼的移动数据帮助研究人员确定，四分之一的鲨鱼栖息地也位于活跃的捕鱼区。这项研究发表在7月25日的《自然》杂志上。

"Our results show major high seas fishing activities are currently centered on ecologically important shark hotspots worldwide" said David Sims, study author and team leader with the Global Shark Movement Project based at the Marine Biological Association Laboratory in Plymouth, UK.

“我们的研究结果表明，目前主要的公海捕鱼活动都集中在世界范围内具有重要生态意义的鲨鱼聚集地区，”大卫·西姆斯说，他是这项研究的作者，也是英国普利茅斯海洋生物协会实验室全球鲨鱼运动项目的负责人。

Oceanic sharks migrate across vast parts of the ocean, and they also account for about half of the sharks pulled in by fisheries. Some of the shark hotspots also overlap in areas where a higher than normal concentration of fishing occurs, which causes more sharks to be caught.

海洋鲨鱼在海洋的大部分地区迁徙，它们也占了渔业捕捞的鲨鱼的一半。一些鲨鱼出没的聚集地区也有重叠，那里的捕鱼活动比正常情况下更为集中，这导致更多的鲨鱼被捕获。

"Some shark hotspots were exposed to higher than average fishing effort for as much as half the year," said Nuno Queiroz, study co-author and researcher at the University of Porto's Center in Biodiversity and Genetic Resources.

“一些鲨鱼聚集地区在长达半年的时间里受到的捕捞量高于平均水平，”研究报告的合著者、波尔图大学生物多样性和遗传资源中心的研究员努诺·奎罗斯说。

And although great white sharks are protected, their populations overlapped 50% with commercial fishing.

尽管大白鲨受到保护，但它们的数量与商业捕鱼的数量重叠了50%。

"Currently, little to no protection exists for sharks in the high seas. It's clear from our study that immediate conservation action is needed to prevent further declines of open-ocean sharks," said Neil Hammerschlag, a study co-author and research associate professor at the University of Miami Rosenstiel School of Marine and Atmospheric Science.

“目前，公海对鲨鱼几乎没有保护。从我们的研究中可以清楚地看到，需要立即采取保护行动，以防止开放式海洋鲨鱼数量进一步减少，”研究合著者、迈阿密大学罗森斯蒂尔海洋与大气科学学院研究副教授尼尔·哈默施拉格说。

"These findings are concerning because as top predators, sharks help maintain healthy ocean ecosystems."

“这些发现令人担忧，因为作为顶级捕食者，鲨鱼有助于维持健康的海洋生态系统。”

The researchers believe a map of hotspots could help determine areas that should be declared as protected to help conservation efforts, as well as quotas to reduce catches.

研究人员认为，(鲨鱼)聚集地区的地图可以帮助确定哪些地区应该被宣布为保护区，以协助保护工作，以及减少捕捞量的配额。

"Some of the shark hotspots we studied may not be there in as little as a few years' time if management measures are not put in place now to conserve the sharks and the habitats on which they depend," Sims said.

西姆斯说:“如果现在不采取管理措施保护鲨鱼和它们赖以生存的栖息地，我们研究的一些鲨鱼聚集地区可能在几年后就不复存在了。”