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Seabird Feathers Reveal Less-Resilient Ocean

Today we have sophisticated buoys¹ packed with instruments, and robotic underwater drones. But a more than a century ago the seas were surveyed by different types of autonomous² data-gathering instruments. Which also happened to be alive:

今天，我们有精密的浮标装满仪器和机器人——水下无人机来水下作业。 但一个多世纪前，海洋由不同类型的自主数据收集工具进行了调查。这也发生了：

"We just call them sea otters³ and white sharks and bluefin tuna." Kyle Van Houtan is director of science at the Monterey Bay Aquarium⁴. And what he means is that marine⁵ mammals and fish and seabirds concentrate unique chemical clues about the ocean and what lives in it, within their tissues. "In their bones, in their feathers, in their vertebrae, in their earwax."

“我们只是称他们为海獭、白鲨和蓝鳍金枪鱼。” Kyle Van Houtan是蒙特利湾水族馆的科学主任。他的意思是海洋哺乳动物、鱼类和海鸟集中在他们的组织内部，关于海洋和生活在海洋中的独特化学线索。“在他们的骨头、羽毛、椎骨的耳垢中。”

For his most recent study, Van Houtan needed to locate feathers from some long-dead birds."Let's see, so I'm just looking here, that was a Bulwer's petrel, from French Frigate⁶ Shoals--I have the database open in front of me here…." Molly Hagemann, who describes herself as 'a librarian for dead animals' at Honolulu's Bishop⁷ Museum, was able to help.

对于他最近的研究，Van Houtan需要找到一些长长的死鸟羽毛。“让我们看看，所以我只是在这里看，这是一个来自法国护卫舰Shoals的Bulwer的海燕——我的数据库在前面打开，我在这里......“。在檀香山的主教博物馆，Molly Hagemann自称为“死亡动物图书管理员”，能够提供帮助。

"So that one was collected in May 1891. And then we also had a brown noddy from 1895…"The scientists analyzed⁸ the ratios of heavy to light nitrogen isotopes⁹ in those old feathers, compared to ratios in modern-day specimens¹⁰. And they found that Pacific seabirds of yore ate diets dominated by fish. But the birds of today were fishing farther down in the food web. And seemed to be eating nearly twice as much squid as their ancestors did—maybe due to the combined effects of commercial fishing and climate change. The details are in the journal Science Advances.

“所以那个是在1891年5月收集的。然后我们也从1895年开始出现褐色的结瘤。”科学家们分析了那些老羽毛中重氮氮同位素的比例，与现代标本中的比率相比。他们发现太平洋海鸟食物曾经以鱼为主。但今天的鸟儿正在食物网中更远的地方找寻食物。而且似乎要吃的东西几乎是其祖先的两倍——可能是由于商业捕鱼和气候变化的综合影响。详情请见《科学进展》杂志。

Now, nothing against consuming calamari. But: “KVH: It's a risky¹¹ business to depend on squid. Because squid go through these boom/bust cycles." So the shift in protein source could one day leave the birds hungry.But the bigger picture is that it appears food webs in the central Pacific have lost components¹² and become less complex over the last 130 years—meaning they're less resilient to changes.

现在，对消费鱿鱼没有什么反对声音。但是：“KVH：依靠鱿鱼是一件冒险的事情。因为鱿鱼经历了这些繁荣/萧条周期。”因此，蛋白质来源的转变有一天可能会让鸟类饥饿。但更大的情况是，似乎中太平洋地区的食物网，在过去的130年中已经失去了组成部分，并且变得不那么复杂。这意味着他们对变化的适应能力较差。

KVH: "It's more than just climate: It's all the noise we're adding to the ocean. All of the contaminants, the microplastic. It's a warming ocean. It's an ocean with more nutrients¹³. It's an ocean with less oxygen."And it’s an ocean with less capacity to recover from all those insults.

KVH：“它不仅仅是气候：这是我们加入海洋的所有噪音，所有的污染物，微型弹性体，它是一个温暖的海洋，它是一个营养物质含量更高的海洋，它是一个氧气含量较少的海洋。” 这是一个能够从所有这些侮辱中恢复过来的海洋。