Baby Whales Pecked to Death by Gulls

海鸥啄死幼鲸

撰文/播音 杰森·G·高曼（Jason G. Goldman）

翻译 Meatle

审校 陈娉莹

Almost all southern right whale calves off the coast of Argentina's Peninsula Valdez are being fed upon, some fatally, by kelp gulls, which was a rare occurrence four decades ago.

几乎所有居住在阿根廷瓦尔德斯半岛附近海域的南露脊鲸的幼鲸都成为了黑背鸥的猎食对象，其中一些幼鲸因此而死亡。在过去的40年中，这是一种罕见的现象。

Gulls. You may have noticed that gulls can be pretty aggressive when it comes to grabbing food. But that behavior is more intense than you may know. Some kelp gulls snack on baby whales. Live baby whales.

你或许曾留意到，当海鸥捕食的时候，它们会表现得相当凶残，然而，实际的攻击性可能会超出你的想象。一些黑背鸥甚至去猎食幼鲸，活的幼鲸。

In the early 1970s, only a handful of southern right whales were fed upon by kelp gulls off the coast of Argentina’s Peninsula Valdez. Back then just two percent of calves every year had to suffer at the beaks of the gulls, along with some of their mothers.

20世纪70年代早期，在阿根廷瓦尔德斯岛附近海域，只有一小撮南露脊鲸受到黑背鸥的侵扰。在那时候，每年只有2%的幼鲸以及它们的母亲不得不经受黑背鸥鸟啄的洗礼。

But now, 99% of the calves have to contend with hungry gulls driving their hooked beaks deep into their backs, ripping out chunks of skin and flesh and blubber, and gobbling it up. The finding is in the journal PLOS ONE. [Carina F. Marón et al, Increased Wounding of Southern Right Whale (Eubalaena australis) Calves by Kelp Gulls (Larus dominicanus) at Península Valdés, Argentina]

而现在，99%的幼鲸需要面对饥饿的海鸥群，任由那带倒钩的喙深深刺入它们的背脊，撕下并吞食一大片的皮肤、血肉与脂肪。这项发现发表在《公共科学图书馆期刊》上。

"Each gull has its own whale and it protects it." University of Utah Biologist Victoria Rowntree. "Or maybe two gulls will have its own whale, and they'll chase off any gulls that come in. And they just sit in the water waiting for the whale to surface again…They’re relentless."

“每只海鸥都紧盯着一条鲸鱼，并维护着对这鲸鱼的主权。”犹他大学的生物学家维多利亚·朗特里说，“或者每两羽海鸥共同‘占有’一条鲸鱼，它们会驱逐其他侵犯它们主权的海鸥。同时，它们也会停留在海面上，静静等待鲸鱼上浮。它们毫不留情。”

Adult whales have learned to arch their backs when they surface to breathe, keeping most of their body away from the hungry gulls. But the newborns can't do that.

成年的鲸鱼懂得在呼吸的时候弯下身来，使身体尽可能地远离饥饿的海鸥。但年幼的个体并不会这样做。

"You can see the mothers getting so annoyed…when finally she's been able to sleep, and she hasn't arched her back, and she is isn't horizontal to the surface, and her calf is sleeping next to her and then a gull comes along and BAMMO…I think the study I did in 1998 showed it took 30 minutes for them to return to normal behavior and not do this avoidance behavior."

“你能看到鲸鱼妈妈是如何变得烦躁的：当它差不多进入梦乡的时候，它的身体既不是弯着的，也不是与海面平行，它的儿女睡在身旁，紧接着一羽黑背鸥出现，打破了它们的睡眠。在我1998年的研究中，我发现它们需要30分钟的时间去进行规避，才能进而恢复到正常状态。”

More than 600 calves died between 2003 and 2014. Some years at least a fifth of all newborns perished. Researchers wonder if the gulls might be, if not responsible, then at least contributing to the pattern. Rowntree looked at whether the dead calves had more gull-inflicted lesions than those that survived, but she found that all of the youngsters get harassed.

在2003年到2014年间有600头幼鲸死亡。其中一些年内，有差不多五分之一的新生鲸鱼死亡。研究人员认为，即使黑背鸥并非幼鲸死亡的直接责任者，它们也对这种现象做出了贡献。朗特里想找出那些死去的幼鲸是否比幸存者承受了更多的海鸥袭击，然而她发现所有的幼鲸都曾经受到黑背鸥的侵扰。

It’s not that the gulls are evil, of course. They eat to survive. The challenge for these researchers is to come up with ways of protecting the whales, without simply wiping out the gulls.

海鸥也并非邪恶，它们只是需要生存所需的食物。研究人员所面临的挑战是，要找到一种方法，既能保护鲸鱼，又并非简单地消灭海鸥。