How giant sea creatures eat tiny sea creatures - Kelly Benoit-Bird

Transcriber: Andrea McDonough Reviewer: Jessica Ruby

翻译人员: sherry lee 校对人员: Cissy Yun

One of the reasons that I'm fascinated by the ocean

我如此着迷于海洋的原因之一

is that it's really an alien world on our own planet.

在于这是我们这个星球上一个特别不同寻常的世界

From our perspective,

从我们的角度来说

sitting on the shoreline or even out on a boat,

坐在海岸边或在坐在船上出海

we're given only the tiniest glimpses

我们只在这些活动中

at the real action that's happening

看到了非常小的一部分

beneath the surface of the waves.

在海浪的表面之下

And even if you were able to go down there,

即使你能潜入海水中

you wouldn't see very much

你能看到的仍旧不多

because light doesn't travel very far in the ocean.

因为光线无法穿入海水太深的部分

So, to answer questions about how the ocean works,

因此，为了回答“海洋如何运作”这个问题

in my research, we use sound.

我们在研究里运用了声音

We use sonars that send out pulses of sound

我们用声呐，发送出脉冲声

made up of a number of different frequencies, or pitches,

这是由一些不同频率或音调组成的声音

that are shown with different colors.

它们由不同的颜色表现出来

That sound bounces off things in the habitat

这些声音在自然环境中不停反弹

and comes back to us.

然后弹回来

If it were to bounce off this dolphin,

如果它在海豚身上反弹

the signal we got back

我们得到的信号

would look very much like the one we sent out

会与我们发送出去的非常相像

where all the colors are represented pretty evenly.

所有颜色都非常均匀地分布

However, if we were to bounce

然而，如果我们使同样的声音

that same sound off of a squid,

在乌贼身上反弹

which in this case is about the same size as that dolphin,

而这个乌贼体积与海豚一样大

we'd instead only get the lowest frequencies back strongly,

反弹最厉害的只会是最低频率的部分

shown here in the red.

也就是红色的部分

And if we were to look at the prey of that squid,

如果我们观察乌贼的食物

the tiny little krill that they're eating,

也就是他们在吃的磷虾

we would instead only get the highest frequencies back.

我们得到的将会是最高频率的部分

And so by looking at this,

所以通过观察这些反弹

we can tell what kinds of animals are in the ocean,

我们就可以得出海洋里有什么样的动物

we can look at how dense they are,

我们可以得出它们的密度

where they are distributed,

它们的分布

look at their interactions

它们交流的方式

and even their behavior

甚至它们的行为

to start to study the ecology of the ocean.

以研究海洋中的生态系统

When we do that, we come up with

当我们进行研究时，我们发现了一些

something sort of surprising:

令人有点意外的事情

on average, there isn't very much food in the ocean.

平均而言，海洋中并没有太多的食物

So even in places which we think of as rich, the coasts,

即使在我们认为富饶的地方，也就是海岸

we're talking about two parts of every million contain food.

那里所有的食物也只占了整个海洋的百万分之二

So what does that mean?

这意味着什么？

Well, that means that in the volume of this theater,

这意味着在这个讲厅中

there would be one tub of movie theater popcorn

只有一桶爆米花这么多的食物

available to be eaten.

可以吃

But of course, it wouldn't be collected

当然，这些食物不会给你

for you neatly in this bucket.

整齐的放在一个桶里

Instead, you'd actually have to be swimming

相反，你需要向威利·旺卡那样，在整个地方

through this entire volume Willy Wonka style,

到处游来游去

picking off individual kernels of popcorn,

捡起一颗颗爆米花

or perhaps if you were lucky,

而幸运的话

getting a hold of a few small clumps.

或许能得到一小块连在一起的

But, of course, if you were in the ocean,

当然，如果你身处海洋中

this popcorn wouldn't be sitting here

这些爆米花也不会就这样呆着不动

waiting for you to eat it.

等着你去吃

It would, instead, be trying to avoid becoming your dinner.

相反，它会极尽所能以避免成为你的食物

So I want to know how do animals solve this challenge?

所以我想知道动物们是如何解决这个难题的

We're going to talk about animals in the Bering Sea.

先来了解一些白令海峡里的动物

This is where you may have see "Deadliest Catch" framed,

这里也是“致命渔夫”的拍摄地

in the northernmost part of the Pacific Ocean.

在太平洋的最北端

We've been looking specifically at krill,

我们专注观察磷虾

one of the most important food items in this habitat.

它们在这个环境中最重要的一种食物

These half-inch long shrimp-like critters

这种虾状的半英尺长的小动物

are about the caloric equivalent

它的热量相当于

of a heavily buttered kernel of popcorn.

油量极大的爆米花

And they're eaten by everything

有很多动物会吃磷虾

from birds and fur seals that pick them up one at a time

从一次叼一只的鸟类与海狗，

to large whales that engulf them in huge mouthfuls.

到一大口吞一群的大型鲸鱼

So I'm going to focus in the area

所以我专注的领域是

around three breeding colonies for birds and fur seals

三个鸟类与海狗的繁殖地区

in the southeastern Bering Sea.

位于白令海峡的东南部

And this is a map of that habitat

这是张栖息地的地图

that we made making maps of food

我们用以往制作食物分布图的方式

the way we've always made maps of food.

制作了当地的食物分布图

This is how many krill are in this area of the ocean.

这是磷虾在当地海域的数量

Red areas represent lots of krill

红色区域代表数量很多

and purple basically none.

紫色代表几乎没有

And you can see that around the northern two most islands,

你可以看到在北部两个主要陆地周围

which are highlighted with white circles

有白色圈圈住

because they are so tiny,

因为它们很小

it looks like there's a lot of food to be eaten.

使当地看上去有很多可以吃的

And yet, the fur seals and birds on these islands

但是，在陆地上的海狗和鸟类

are crashing.

处境非常艰难

Their populations are declining

它们的数量正在减少

despite decades of protection.

尽管进行了数十年的保护措施仍是如此

And while on that southern island

而在南部的岛屿上

at the very bottom of the screen

在屏幕底端

it doesn't look like there's anything to eat,

看上去几乎没什么可以吃的

those populations are doing incredibly well.

然而当地的生物数量却保持得非常的好

So this left us with a dilemma.

这就使我们处于一个两难境地中

Our observations of food don't make any sense

我们对食物分布的调查

in the context of our observations of these animals.

对这些动物根本说明不了什么

So we started to think about how we could do this differently.

所以我们开始考虑采取不同的做法

And this map shows not how many krill there are,

这个地图显示的不是磷虾的数量

but how many clumps of krill there are,

而是磷虾种群的数量

how aggregated are they.

它们聚集的程度如何

And what you get is a very different picture of the landscape.

你所得出的是完全不同的情况

Now that southern island looks

如今南部的岛屿变成了

like a pretty good place to be,

一个很适宜的地方

and when we combine this

当我们把这些

with other information about prey,

与其他猎物的信息结合在一起的时候

it starts to explain the population observations.

我们就能很好地解释观察对象的数量分布

But we can also ask that question differently.

而我们还可以从不同的角度回答这个问题

We can have the animals tell us what's important.

我们可以让这些动物告诉我们重点在哪

By tagging and tracking these animals

方法是对这些动物贴上标签，进行跟踪

and looking at how they use this habitat,

然后观察它们如何利用这片栖息地

we are able to say, "What matters to you?"

我们将要问的是：“对你们而言什么才是重要的？”

about the prey.

这是就猎物所提出的问题

And what they've told us

它们所回答的

is that how many krill there are really isn't important.

是磷虾的数量其实并不重要

It is how closely spaced those krill are

重要的是它们的分布密集程度

because that's how they are able to make a living.

因为这是它们生命得以维系的方式

We see the same pattern

我们可以在其他海域

when we look in very different ocean,

看到同样的模式

further south in the Pacific,

出现在在太平洋的更南端

in the warm waters around the Hawaiian islands.

在夏威夷岛屿附近的温暖水域

So a very different habitat,

因此截然不同的栖息地

and yet the same story.

运作原理是可以一样的

Under some conditions,

在一些条件下

the physics and the nutrients, the fertilizer,

如物理条件、营养物、肥料等

set up aggregations in the plants, the phytoplankton.

就可以建立其植物群落，如浮游植物群

And when that happens,

当群落建成时

these very dense aggregations of phytoplankton

这些紧密聚集在一起的浮游植物

attract their predators,

把捕食者吸引了过来

which themselves form very dense layers.

而这些捕食者自身也以层状紧密分布

That changes the behavior and distribution

这同时改变了捕食者们的

of their predators as well,

行动和分布

starting to set up how this entire ecosystem functions.

这也开始建立起整个生态系统的运作模式

Finally, the predators that eat

自后，这些捕食者

these small fish, shrimp, and squid,

把这些小鱼、小虾和乌贼吃掉

we're talking about two- to three-inch long prey here,

这些食物都有2-3英尺长

changes how they use their habitat

这也改变了它们利用栖息地

and how they forage.

以及觅食的方式

And so we see changes in the spinner dolphins

同时我们也看到飞旋海豚身上发生的变化

that are related to the changes

也与这些改变相关

we're seeing in the plant life.

我们对植物生物进行了研究

And just by measuring the plants,

通过对这些植物进行测量

we can actually predict very well

我们可以准确地预测出

what's going to happen in the top predator

经历食物网三个环节后

three steps away in the food web.

顶级捕食者身上会发生什么

But what's interesting is

而有趣的是

that even the densest aggregations of their prey

即使这些猎物以最紧密的形式分布

aren't enough for spinner dolphins to make it.

仍旧不能满足飞旋海豚的生存需要

It's a pretty tough life there in the ocean.

海洋中的生活非常艰辛

So these animals actually work together

所以这些生物实际上共同合作

to herd their prey into even denser aggregations,

把它们的猎物赶进更密集分布的群落中

starting with patches that they find in the first place.

它们首先开始于自己找到的小块区域

And that's what you're going to see in this visualization.

这就是你所看到的这个演示

We have a group of 20 dolphins,

我们有一组由20条海豚组成的小组

you notice they're all set up in pairs,

你可以看到它们以成对方式

that are working together

进行合作

to basically bulldoze prey

简单来说就是威吓猎物

to accumulate it on top of itself.

使它们堆在一起

And once they do that,

一旦这么做了之后

they form a circle around that prey

它们就会围绕猎物形成一个圈

to maintain that really dense patch

以维持猎物的密集分布

that is a couple thousand times higher density

这个聚集物的密度将会比开始的时候

than the background that they started with

高出几千倍

before individual pairs of dolphins

此前成对的海豚

start to take turns feeding

轮流喂养

inside this circle of prey that they've created.

这些困在它们所建造围栏里的猎物

And so, this work is showing us

因此，它们的工作告诉我们

that animals can first give us the answers

动物们可以首先给出答案

that aggregation is critical to how they make their living.

也就是聚集的群落对维系动物的生命非常重要

And by looking more deeply at the ocean,

通过更深入地观察海里的生物

we're starting to understand our interactions with it

我们开始了解我们是如何与它们相互作用的

and finding more effective ways of conserving it.

同时能够找到更有效的方式对它们的环境进行保护

Thank you.

谢谢大家