Charles Anderson discovers dragonflies that cross oceans

翻译人员: An Li 校对人员: Zachary Lin Zhao

Actually, I come from Britain,

实际上我是从英国来，

but I've been living in Maldives for 26 years now.

但是我已经在马尔代夫住了26年了。

So, that's home really.

所以那里是我真正的家。

The Maldives, as I'm sure you're aware, are a chain of islands

你们肯定都知道，马尔代夫是群岛

off the southwest coast of India here.

位于印度的西南面。

Capital, Malé, where I live.

首都是马累，我就住在那里。

Actually, sitting here today in Mysore,

其实，我们所在的这个地方迈索尔，

we're closer to Malé than we are to Delhi, for example.

离马累要比离德里更近一些。

If you're in IT, India, obviously, is the place to be at the moment.

如果你在信息技术行业，印度很显然是现在最好的所在。

But if you're a marine biologist, Maldives is not such a bad place to be.

但是如果你是海洋生物学家，马尔代夫是一个不错的地方。

And it has been my home these years.

正是如此，这些年她就成了我的家。

For those of you who've been there, fantastic coral reefs,

如果你到过那里，就知道那里有超棒的珊瑚礁，

fantastic diving, fantastic snorkeling.

超棒的潜水，超棒的浮潜。

I spend as much of my time as possible

我全部精力都用来

investigating the marine life.

研究海洋生物。

I study fish,

我研究鱼类，

also the bigger things, whales and dolphins.

也研究更大的动物，像鲸和海豚。

This is a blue whale. We have blue whales

这是只蓝鲸。 蓝鲸出现在

in the waters around here, off Maldives,

马尔代夫周围的水域，

around the waters of India. You can see them off Kerala.

和印度周围的水域。 你可以在Kerala附近看到它们。

And, in fact, we're very lucky in this region.

是的，我们在这个地区确实是很幸运。

One of the best places in the world to see blue whales

在全球观看蓝鲸最好的地方中，

is here in this region.

这个地区就是其中之一。

In Sri Lanka, if you go down to the south coast of Sri Lanka,

在斯里兰卡，如果你在东北季候风季节

during the northeast monsoon season,

去斯里兰卡的南部海岸的话，

you can see blue whales very, very easily.

你很容易就会看到蓝鲸。

It's probably the best place in the world to see them.

那里可能是世界上最容易看到蓝鲸的地方。

Now, when I talk about the northeast monsoon season,

好，当我说到东北季候风的时候，

I'm sure many of you here know exactly what I mean,

你们很多人肯定很清楚我指的是什么，

but perhaps some of you are not quite so sure.

但是也可能一些人不太清楚。

I need to explain a little bit about monsoons.

我需要稍微解释一下季候风是怎么回事。

Now, monsoon, the root of the word "monsoon"

好，”季候风“这个词的字根

comes from the word "season."

是从“季节”这个词而来。

So, it's just a season. And there are two seasons in most of South Asia.

所以，它只是一个季节。而在大多数南亚地区，有两个季节。

And in the summer India heats up, gets very hot.

夏天时印度渐渐热起来，直到变得很热。

Hot air rises, and air is drawn in off the sea to replace it.

热空气上升，所以海洋上空的空气就被吸过来补充。

And the way it works is, it comes from the southwest.

按理来说，它是从西南方向来。

It comes off the ocean here and is drawn up towards India.

它是从这里的洋面，被吸引到印度。

So it comes from the southwest. It's a southwest monsoon.

所以它是从西南方向来。称为西南季候风。

Picks up moisture as it crosses the ocean.

空气流过洋面，吸收水汽

That's what brings the monsoon rain.

就带来了季候雨。

And then in the winter things cool down.

然后到冬天时，气候变冷，

High pressure builds over India.

高气压在印度上空积聚，

And the whole system goes into reverse.

使整个系统反转过来

So, the wind is now coming from the northeast

于是，风就从东北方向吹过来

out of India, across the Indian Ocean,

从印度大陆吹过印度洋

this way towards Africa.

沿这个方向吹向非洲。

Keep that in mind.

记住这一点。

Now, I'm a marine biologist, but I'm actually

好，我是海洋生物学家。可我实际上

a bit of an old fashioned naturalist, I suppose.

觉得我有点像个老式的自然学家。

I'm interested in all sorts of things, almost everything that moves,

我对各种各样的事情都感兴趣，包括差不多所有动的东西，

including dragonflies. And I'm actually

也包括蜻蜓。今天下午

going to talk, this afternoon, about dragonflies.

我就要跟你们谈谈蜻蜓。

This is a very beautiful species, it's called the Oriental Scarlet.

这是一个非常美丽的品种，它叫做东方猩红蜻蜓。

And one thing you need to know about dragonflies,

你们需要知道关于蜻蜓的一件事，

one important thing,

一件很重要的事，

is that they lay their eggs in fresh water.

是它们在淡水中产卵。

They need fresh water to breed.

它们需要淡水来繁殖。

They lay the eggs into fresh water.

它们把卵产在淡水中，

Little larvae hatch out in fresh water.

小小的幼虫在淡水中孵化出来，

They feed on other little things. They feed on mosquito larvae.

它们捕食其它小动物，包括蚊子的幼虫

So, they're very important.

所以它们非常重要。

They control mosquito larvae, among other things.

除了别的，它们还控制蚊子的幼虫。

And they grow and grow by stages. And they climb out

它们在生长了几个阶段之后，从水里爬出来，

of the water, burst out, as the adult which we see.

蜕皮而出，成为我们看到的成虫。

And typically, there is a lot of variation,

当然，不同种类间的差异各种各样，

but if you have a dragonfly with, say, a one year life cycle,

但是如果你有一种蜻蜓，生命周期为一年，

which is quite typical, the larva, living in the fresh water,

这样一个很典型的周期，它的幼虫，会在淡水中生活

lives for 10 or 11 months.

10或11个月。

And then the adult, which comes after, lives for one or two months.

而它的成虫，随后出来，再活一或两个月。

So it's essentially a freshwater animal.

因此它实质上是一种淡水动物。

It really does need fresh water.

它真的需要淡水才能生存。

Now, the particular species of dragonfly

好了，我要讲到的一种很特别的蜻蜓

I want to talk about is this one,

就是这种，

because most dragonflies, like the one we've just seen,

因为大多数的蜻蜓，像我们刚刚看到的那种，

when the adult is there for its brief one or two months of life,

在它短暂的一两个月的成虫期，

it doesn't go very far. It can't travel very far.

并不会飞很远。它不能走很远。

A few kilometers, maybe, is quite typical.

典型的大概就是几公里。

They are very good fliers, but they don't go too far.

它们非常善于飞行，但是它们不会飞很远。

But this guy is an exception.

但这个家伙是个例外。

And this is called the Globe Skimmer,

它的名字叫做全球点水蜻蜓，

or Wandering Glider.

或者叫漫游滑翔蜻蜓。

And, as the name might suggest, it is found pretty much around the world.

所以就像它的名字一样，在世界各地都能找到它。

It lives throughout the tropics, the Americas,

它的分布遍及热带地区，美洲地区，

Africa, Asia, Australia, into the Pacific.

非洲，亚洲，澳大利亚，直到太平洋地区。

And it wanders far and wide. We know that much about it.

所以它漫游得非常广泛。我们对它就知道那么多。

But it really hasn't been studied very much.

但是它并没有被好好研究过，

It's a rather mediocre looking dragonfly.

因为它的长相实在是很一般。

If you're going to study dragonflies, you want to study those really bright beautiful ones,

如果你要去研究蜻蜓的话，你会想去研究那些颜色很鲜亮美丽的，

like that red one. Or the really rare ones, the endemic endangered ones.

像那只红的，或者那些很稀有的，本地濒危种类。

This is, it seems a bit dull you know.

这个嘛，看起来很不起眼

It's sort of dull-colored. And it's fairly common.

它的颜色有点暗淡，并且相当常见。

And it occurs everywhere -- you know, why bother?

任何地方都可以看到 -- 你就会想，干嘛费那个劲？

But if you take that attitude, you're actually missing something rather special.

但是如果你有那种态度的话，你就会错过一个非常特别的发现。

Because this dragonfly has a rather amazing story to tell.

因为这种蜻蜓有一个非比寻常的故事。

And I feel very privileged to have stumbled across it

是我住在马尔代夫时，

living in the Maldives.

非常荣幸地偶然发现的

When I first went to the Maldives,

我第一次到马尔代夫的时候，

dead keen on diving, spent as much of my time

醉心于潜水，所有的时间

as I could in and under the water.

都花在水里和水下，

Didn't notice any dragonflies; maybe they were there, maybe they weren't.

并没有注意到任何的蜻蜓；可能有，可能没有，

Didn't notice them.

我都没注意。

But after some time, after some months, one day

但是过了一段时间，几个月之后，有一天

as I was going out and about,

我在外面走的时候，

suddenly I noticed hundreds of dragonflies, hundreds of dragonflies.

我突然注意到上百只的蜻蜓，几百只的蜻蜓，

Something like this, these are all this species Globe Skimmer.

就像这样，这些都是全球点水蜻蜓一个品种

I didn't know at the time, but I know now,

我那时候不知道，可我现在知道了

they're Globe Skimmers, hundreds of them.

它们是全球点水蜻蜓，有好几百只。

And they were there for some time. And then they were gone.

它们在那里呆一段时间，然后就不见了。

And I didn't think anything more of it until

我也没去多想，等到

the following year, when it happened again,

第二年，同样的事又发生了，

and then the year after that, and then the year after that.

这样又一年，这样又一年。

And I was a bit slow, I didn't really take too much notice.

我反应又比较慢，没有真正好好注意，

But I asked some Maldivian friends and colleagues, and yes they come every year.

但是我问过一些马尔代夫的朋友和同事，答复是是的，它们每年都来。

And I asked people about them and yes,

我也同样问过一些人，答复也是是的，

they knew, but they didn't know anything,

他们知道是那回事，但是他们不知道为什么，

where they came from, or anything.

它们从哪里来，或者别的什么。

And again I didn't think too much of it.

这次我又没有去多想。

But slowly it began to dawn on me that something

但是慢慢地我突然意识到，有一件

rather special was happening.

很特别的事情在发生。

Because dragonflies need fresh water to breed.

因为蜻蜓需要淡水来繁殖，

And the Maldives, and I'm sure some of you have been there --

可是马尔代夫，我肯定你们有些人到过那里--

so here is home.

好这里就是家，

So, Maldives, beautiful place.

好，马尔代夫，美丽的地方

(Laughter)

（笑声）

It's built entirely of coral reefs.

它完全是由珊瑚礁建成的。

And on top of the coral reefs are sand banks.

珊瑚礁上面是沙洲，

Average height, about that much above sea level.

它的平均高度，大约只有那么一点点高过海平面。

So, global warming, sea level rise, it's a real serious issue.

因此，全球变暖，海平面上升，是个很严重的问题。

But I'm not going to talk about that.

但那不是我今天的话题。

Another important point of these sand banks

这些沙洲的另外一个特点是，

is that when it rains,

下雨的时候，

the rainwater soaks down into the soil. So, it's gone.

雨水渗透到下面的土壤，就没有了。

So, it stays under the soil.

所以，雨水留在土壤下面，

The trees can put their roots into it.

树可以用根来吸收，

Humans can dig holes and make a well.

人可以挖坑凿井，

But dragonflies -- a bit tricky.

可是蜻蜓--就不好办了。

There is no surface fresh water.

没有地表的淡水，

There are no ponds, streams, rivers, lakes,

没有池塘，小溪，河流，湖泊，

nothing like that.

什么都没有，

So, why is it that every year

那么为什么每年

millions of dragonflies, millions,

成百万只的蜻蜓，百万

millions of dragonflies turn up?

百万的蜻蜓会出现呢？

I got a little bit curious. In fact I'll stop here,

我变得很好奇。在这里我想暂停一下

because I want to ask, and there is a lot of people who,

因为我想问个问题，我们这里当然有很多人

from India of course, people who grew up spending your childhood here.

是从印度来，在这里长大，度过你们的童年，

Those of you who are Indian or spent your childhood here,

如果你是印度人，或者在这里长大，

let me have a show of hands, who of you --

请举一下手，有谁 --

not yet, not yet!

还没完，还没完！

You're too keen. You're too keen. No. Hang on. Hang on.

你们太积极了，太积极了。 不，稍等，稍等

Wait for the go. I'll say go.

等我说开始， 我会说开始的。

Those of you who grew up in India,

你们如果在印度长大，

do you remember in your childhood, dragonflies,

记不记得小时候看见蜻蜓，

swarms of dragonflies? Maybe at school,

大群的蜻蜓？可能在学校，

maybe tying little bits of string onto them?

可能给它们系上一节细绳？

Maybe pulling bits off? I'm not asking about that.

可能把它们扯碎？我不想问你们那个。

You've only got to say, do you remember seeing lots of dragonflies.

你只要告诉我，是不是记得看见过很多的蜻蜓。

Any hands? Any hands? Yes. Thank you. Thank you.

请举手， 请举手？好，谢谢，谢谢。

It's a widespread phenomenon

那是在整个南亚，包括马尔代夫

throughout South Asia, including the Maldives.

随处可见的现象。

And I got a bit curious about it.

所以我就很好奇。

In the Maldives -- now, in India there is plenty of water,

在马尔代夫，当然在印度有很多水

so, dragonflies, yeah, of course. Why not?

自然会有很多蜻蜓， 对吧，当然啦。

But in Maldives, no fresh water. So, what on Earth is going on?

但是在马尔代夫，并没有淡水。那，到底是怎么一回事呢？

And the first thing I did was started recording

于是我做的第一件事就是开始记录

when they turned up in the Maldives.

它们在马尔代夫出现的时间。

And there is the answer, 21st of October.

而答案是十月二十一日。

Not every year, that's the average date.

不是每年都在同一天，那是平均日期。

So, I've been writing it down for 15 years now.

那样，我已经记录了15年了。

You'd think they're coming from India. It's the closest place.

你会想它们是从印度来，那是最近的地方。

But in October, remember, we're still in southwest monsoon,

但在十月份的时候，记住，仍然是西南季候风，

Maldives is still in the southwest monsoon.

马尔代夫仍然是西南季候风。

But wind is, invariably, every time, is from the west.

因此风总是每回都从西边来。

It's going towards India, not from India.

它是吹向印度，不是从印度来。

So, are these things, how are these things getting here?

那么，这些家伙，它们是怎样到这里的呢？

Are they coming from India against the wind?

它们是逆风从印度飞过来的吗？

Seemed a bit unlikely.

有点不太可能。

So, next thing I did is I got on the phone.

所以，我接下来开始打电话。

Maldives is a long archipelago.

马尔代夫是一串很长的群岛，

It stretches about 500 miles, of course it's India here.

延伸大约500英里，当然，直到这里。

I got on the phone and emailed to friends and colleagues.

我给我的朋友和同事打电话，发电邮，

When do you see the dragonflies appear?

问他们什么时候看到蜻蜓出现?

And pretty soon, a picture started emerging.

很快地，情况开始明了了

In Bangalore, a colleague there sent me

在班加罗尔，一个同事送给我

information for three years, average,

三年的信息，平均日期是

24th of September, so late September.

九月二十四日，大概九月下旬。

Down in Trivandrum, a bit later.

在往下的 Trivandrum 市， 就迟一点。

Far north of Maldives, a bit later.

在马尔代夫最北端，又迟一点。

Then Malé, then further south.

然后马累，然后更南面，

And then the southernmost Maldives.

然后是马尔代夫的最南端。

It's pretty obvious, they're coming from India.

很明显，它们是从印度来。

But they are coming 400 miles across the ocean, against the wind.

但是他们从400英里外飞越大洋过来，并且是逆风，

How on Earth are they doing that?

它们怎么可能做到呢？

I didn't know.

我当时并不知道。

The next thing I did was I started counting dragonflies.

我做的下一件事情就是开始数蜻蜓的数目。

I wanted to know about their seasonality,

我想知道它们的季节性，

what time of year, this is when they first arrive,

我们知道他们每年开始出现的时间，

but how long are they around for? Does that give any clues?

但是它们会呆多久？它们的数目会不会提供一点线索？

So, I started a very rigorous scientific process.

于是，我开始了一个很严谨的科研过程。

I had a rigorous scientific transect.

我有一种很严谨的科研交通工具，

I got on my bicycle,

我骑上我的自行车，

and I cycled around the island of Malé.

围着马累岛转，

It's about five kilometers around,

一圈大概有五公里，

counting the dragonflies as I go,

一边骑，一边数蜻蜓，

trying not to bump into people as I'm looking in the trees.

向周围的树上看，同时又尽量避免撞到行人。

And they're here for a very short time,

我发现它们在这里只呆一段很短的时间，

October, November, December. That's it.

十月，十一月，十二月，就没有了。

And then they tail off, there's a few, but that's it.

它们数量减少，会剩下少许几只，但基本上就没有了。

October, November, December. That is not the northeast monsoon season.

十月，十一月，十二月。 那不是东北季候风季节，

That's not the southwest season.

也不是西南季候风季节，

That's the inter-monsoon,

那是季候风之间的时期，

the time when the monsoon changes.

季候风变换的时期。

Now, what I said was, you get the southwest monsoon going one way,

好了，我刚才说的是，这里西南季候风向这个方向吹，

and then it changes and you get the northeast monsoon going the other way.

然后它变了，变成东北季候风向相反方向吹。

And that sort of gives the impression you've got one air mass

那可能给你一个印象，就是有一个气团

going up and down, up and down. It doesn't work like that.

在吹上来，吹下去，上来，下去。实际上并不是如此。

What happens, actually, is there is two air masses.

实际上，那里有两个气团。

And there is a front between them, and the front moves.

气团之间有个锋面，锋面在移动。

So, if you've got India here,

所以，如果这里是印度，

when the front is up above India you're into the southwest monsoon.

当锋面在印度上空时，印度就进入西南季候风。

Then the front moves into the northeast monsoon.

然后锋面移走，就进入东北季候风。

And that front in the middle is not vertical,

而且那之间的锋面并不是垂直的，

it's at an angle.

它有一个角度。

So, as it comes over towards Malé

所以，当它向马累这边过来的时候，

I'm standing in Malé underneath the front.

我站在马累，在锋面之下，

I can be in the southwest monsoon.

我就会在西南季候风里。

But the wind above is from the northeast monsoon.

但是这上面的风是从东北季候风来的。

So, the dragonflies are actually coming from India on the northeast monsoon,

所以，这些蜻蜓实际上是搭着东北季候风从印度来的。

but at an altitude at 1,000 to 2,000 meters up in the air. Incredible.

但是是在空中1000到2000米的高度。真不可思议

These little insects, it's the same ones we see out here [in India],

这些小小的昆虫，和我们在外面[印度]看到的一样，

two inches long, five centimeters long,

两英寸长，五厘米长，

flying in their millions, 400 miles across the ocean,

百万只地飞行，飞越400英里的海洋，

at 2,000 meters up. Quite incredible.

在2000米的高空。相当难以置信

So, I was quite pleased with myself. I thought wow, I've tracked this one,

因此，我对我自己相当满意。我想，哇，我跟踪到了这个，

I know how they come here. Then I scratched my head a bit,

我知道它们是怎样到这里的。然后我抓了抓我的头，

and that's okay,

是不错，

I know how they come here, but why do they come here?

我知道它们怎样到这里，但是为什么它们要来这里呢？

What are millions of dragonflies doing, flying out over the ocean every year

这百万只的蜻蜓是在做什么呢？它们每年飞到这海洋上空

to their apparent doom?

就是为了来送死吗？

It doesn't make sense. There is nothing for them in Maldives.

没有道理嘛。在马尔代夫没有它们需要的任何东西。

What on Earth are they doing?

它们到底在做什么？

Well, to cut a long story short,

好吧，长话短说，

they're actually flying right across the ocean.

它们其实是要飞越海洋，

They're making it all the way across to East Africa.

一直要飞到东非去。

I know that because I have friends who work on fisheries' research vessels

我知道是那回事，因为我有朋友在渔场的考察船工作，

who have sent to me reports from boats out in the ocean.

他们从出海的船上送报告给我,

I know because we have reports from Seychelles,

我知道是因为我们有从塞瑟尔来的报告

which fit in as well, down here.

也很吻合，在这里。

And I know because

并且我知道是因为

when you look at the rainfall,

考虑到降雨的因素，

these particular insects, these Globe Skimmers

这些特别的昆虫，这些全球点水蜻蜓，

breed in temporary rain water pools.

是在临时的雨水塘里繁殖的。

Okay, they lay their eggs where the seasonal rains are,

是的，它们产卵的地方，就是有季节性雨的地方，

the monsoon rains.

也就是季候风雨。

The larvae have to develop very quickly.

它的幼虫必须很快地发育，

They only take six weeks. Instead of 11 months, they're six weeks.

它们只需要六个星期，而不是11个月。六个星期后，

They're up, and they're off.

它们就出来，飞走了。

Now, here we have, in case you can't read at the back,

好，我们来看看，如果你在后排，看不清楚的话，

the top is rainfall for India.

这上面是印度的降雨分布。

And we're starting in June. So this is the monsoon rain.

是从六月开始。这些是季候风雨，

By September, October, it's drying out.

到九月，十月的时候，就干掉了。

Nothing for these dragonflies. There is no more seasonal rain.

这些蜻蜓就没有雨了，没有季节性雨水了。

They've got to go hunting for seasonal rain.

它们需要去寻找季节性的雨水。

And they fly south. As the monsoon withdraws to the south

所以它们向南飞，跟着向南退却的季候风

they come down through Karnataka, into Kerala.

它们向下经过Karatka, 进到Kerala，

And then they run out of land.

然后就到了陆地的尽头。

But they are incredibly good fliers. This particular species,

但是它们非常善于飞行。这种特别的种类，

it can fly for thousands of kilometers.

可以飞行上千公里。

And it just keeps going. And the wind, the northeast wind

所以它就一直向前飞。而风，东北风，

swooshes it around and carries it off across the ocean to Africa,

把它卷起来，又带着它穿越大洋直到非洲，

where it's raining.

而那里正在下雨。

And they are breeding in the rains of Africa.

然后它们在非洲的雨水中繁殖。

Now, this is southeast Africa. It makes it look like there are sort of

好，这是东南非洲。这个图使得我们觉得好像有

two breeding periods here. It's slightly more complicated than that.

两个繁殖季节。实际上要稍微复杂一点。

What's happening is they are breeding in the monsoon rains here.

我们看到它们在这里的季候风雨中繁殖，

And the dragonflies you can see today

就像你们今天看到的蜻蜓

outside here, on the campus,

在外面校园里的这些，

are the young of this generation.

是这一代的后代。

They hatched out in India.

它们在印度孵化出来，

They're looking for somewhere to breed. If it rains here they'll breed.

正在寻找地方繁殖。如果这里下雨，它们就会繁殖。

But most of them are going to carry on. And next stop,

但是它们中的多数都会继续向前飞。那下一站，

perhaps only four or five days away is going to be East Africa.

可能仅仅四五天的距离，就是东非。

The wind will swoosh them out across here.

风会带着它们过到这里。

If they pass the Maldives they might go and have a look,

如果它们路过马尔代夫，它们可能去看一看，

nothing there, they'll carry on.

找不到什么的话，它们就继续。

Here, here, Kenya, East Africa,

这里，这里，肯尼亚，东非

they've actually just come out of a long drought.

他们刚刚经历了很长时间的干旱，

Just last week the rains broke. The short rains broke

直到上周才开始下雨。下了几场阵雨，

and it's raining there now.

现在还在下。

And the dragonflies are there. I have reports from my various contacts.

而蜻蜓正在那里。我从我好几个联系人那里得到报告，

The dragonflies are here now. They're breeding there.

说蜻蜓来了，正在那里繁殖。

When those guys, they'll lay their eggs now.

所以这些家伙，它们正在产卵。

They'll hatch out in six weeks. By that time

六个星期后它们就会飞出来。那时候

the seasonal rains have moved on. It's not there, it's down here.

季节性雨已经向前移动了。不在那里，是在这下面。

They'll fly down here. And the clever thing is

它们会飞下来。而很奇妙的一件事是

the wind is always converging to where the rain is.

风总是汇聚到下雨的地方。

The rain occurs, these are summer rains.

雨下下来，这些都是夏天的雨。

This is a summer monsoon.

这是夏天的季候风。

The sun is overhead there. Summer rains in southern Africa.

太阳在那里当头照着。在南非夏天降雨时，

The sun is overhead, maximum heating,

太阳正当头，加热最强烈，

maximum evaporation, maximum clouds,

蒸发最强烈，云最多，

maximum rainfall,

雨最多，

maximum opportunities for reproduction.

给繁殖提供最多的机会。

Not only that, because you have this convection,

不仅如此，因为有空气对流，

you have this rising of the air

在热的地方有空气的上升，

where it's hot, air is drawn in.

空气就被吸过来。

There's a convergence. So, wherever the rain is falling,

形成一种汇聚效应。所以，无论是在哪里下雨，

the air is drawn towards it to replace the air that's rising.

空气就被吸到那里去补充上升的空气，

So, the little fellow that hatches out here,

所以，在那里孵化出来的小家伙，

he gets up into the air, he is automatically carried

它飞到空中，被自动地带到

to where the rain is falling.

正在下雨的地方。

Lay their eggs, next generation, they come up,

在那里产卵，下一代又出来，

automatically carried to where the rain is falling.

被自动地带到正在下雨的地方。

It's now back there. They come out, it's time to come back.

现在已经回那里了。它们出来，就到了回去的时候了。

So, in four generations, one, two, three,

所以，四代之后，一，二，三，

four and then back.

四，它们就回来了。

A complete circuit of the Indian Ocean.

一个完整的跨印度洋的循环。

This is a circuit of about 16,000 kilometers.

这个循环大概有16,000公里。

16,000 kilometers, four generations, mind you,

16,000公里，四代，请注意，

for a two inch long insect. It's quite incredible.

对一种两英寸长的昆虫来说，是非常不可思议的。

Those of you from North America

如果你从北美来，

will be familiar with the Monarch butterfly.

你会对帝王蝶很熟悉，

Which, up until now has had the longest known insect migration.

它是迄今为止所知的迁徙距离最长的昆虫。

It's only half the length of this one.

但只有这个距离的一半。

And this crossing here, of the ocean,

而且这个跨越大洋的飞行，

is the only truly regular transoceanic crossing

是在所有昆虫中唯一真正有规律的

of any insect.

越洋飞行，

A quite incredible feat.

一个非常了不起的壮举。

And I only stumbled on this because I was living in Malé,

我是因为住在马累才偶然发现了这点的，

in Maldives for long enough

在马尔代夫住了很长时间之后，

for it to percolate into my brain

我才慢慢地意识到

that something rather special was going on.

有一些很特别的事情正在发生。

But dragonflies are not the only creatures that make the crossing.

但是蜻蜓并不是完成这个飞越唯一的动物，

There is more to the story.

这个故事还没完。

I'm also interested in birds. And I'm familiar

我对鸟也感兴趣。我也很熟悉

with this fellow. This is a rather special bird.

这个家伙。这是种很特别的鸟。

It's a falcon. It's called the eastern red-footed falcon, obviously.

这是一只隼，叫做东方红脚隼，很显然。

But it's also called the Amur Falcon.

但它也叫做阿穆尔隼。

And it's called the Amur Falcon

把它叫做阿穆尔隼的原因是它

because it breeds in Amurland.

在阿穆尔地繁殖。

Which is an area along the Amur River, which is up here.

是阿穆尔河流经的区域，在这上面。

It's the border, much of it is the border

很长一段是中国和俄国的边界

between China and Russia, up here in the far east.

在远东这里

So, Siberia, Manchuria.

所以，西伯利亚，黑龙江，

And that's where it breeds.

就是它们繁殖的地方。

And if you're a falcon it's quite a nice place to be in the summer.

如果你是只隼的话,在夏天那里是一个很不错的地方，

But it's a pretty miserable place to be in the winter.

但是在冬天是一个很难捱的地方。

It's, well, you can imagine.

你很容易想象出来。

So, as any sensible bird would do,

所以就像任何明智的鸟儿一样，

he moves south. They move south. The whole population moves south.

它就向南飞，它们向南飞，整个种群都向南飞。

But then the being sensible stopped.

可是后来好像变得不明智了。

So, now they don't stop here, or even down here.

因为它们并不停在这里，或甚至这里，

No, they turn across here.

不，它们从这里转过来，

They have a little refueling stop in northeastern India.

在印度的东北部稍微停留补充一下，

They come to the latitude of about Mumbai or Goa.

再到孟买或者果阿这个纬度休息，

And then they strike out across the ocean, down to Kenya.

然后猛地飞过印度洋，到了肯尼亚。

And down here, and they winter down here [in southern Africa].

在这下面，它们就在这里越冬【在南非】。

Incredible. This is the most extraordinary migration

不可思议。这是在所有猛禽中

of any bird of prey. A quite incredible migration.

最特别的迁徙，非常不可思议。

And they are not the only one that makes the crossing.

然而，它们并不是唯一飞越大洋的鸟类。

They have the most incredible journey, but several make the crossing from India

它们的旅程是最了不起的，但是其他好几种鸟也从印度越洋飞到

to Africa. Includes this one, the hobby.

非洲去。包括这种鸟，燕隼。

This fellow is a very nice bird, this is the Pied cuckoo.

这是只很漂亮的鸟，叫做斑翅凤头鹃。

Those of you from northern India will be familiar with this.

你们从印度北部来的让对它会很熟悉。

It comes with the monsoons.

它和季候风一起到来。

This time of year they cross back to Africa.

每年的这个时候他们就飞回非洲去。

And this guy, the roller, a rather beautiful bird.

还有这个家伙，三宝鸟，一种相当漂亮的鸟。

It's known as the Eurasian Roller. In India it occurs in the northwest,

它也叫做欧亚三宝鸟。在印度西北部出现时，

so it's known as the Kashmir Roller.

人们叫它克什米尔三宝鸟。

And these birds, what I've done is I've complied all the records,

所有这些鸟，我所作的就是整理了所有我能找到的

all the available records of these birds,

关于这些鸟儿的资料，

put them together, and found out they migrate at exactly the same time

把它们放在一起，就发现它们沿着和蜻蜓完全一样的路线

as the dragonflies.

迁徙。

They make use of exactly the same winds.

它们利用同样的风。

They travel at exactly the same time with the same winds

它们在完全一样的时间，利用同样的风飞行，

to make the crossing. I know they travel at the same altitude.

来飞越大洋。我知道他们在同一个高度飞行，

It's known about the Amur Falcon. This guy, unfortunately,

我们已经知道阿穆尔隼是这样的。这个家伙，很不幸地，

one of these met an unfortunate end.

有一只这种鸟的结局很不幸，

He was flying off the coast of Goa,

它在离果阿海岸不远的地方飞，

21 years ago, 1988. October, 1988.

在21年前，1998年十月，

An Indian Navy jet was flying off Goa,

一架印度海军喷气机正在离果阿海岸不远的地方飞，

bang! In the middle of the night. Fortunately, a two engine jet

嘭的一声，半夜的时候，幸好是一架双引擎飞机，

got back to base, and they pulled the remains of one of these [Eurasian Rollers] out.

飞会基地后，他们取出了一只这种鸟【欧亚三宝鸟】的残骸。

Flying at night over the Indian Ocean 2,424 meters.

它在半夜在印度洋上2424米的高空飞行，

Same height as the dragonflies go.

和蜻蜓飞的高度一样。

So, they are using the same winds.

所以它们利用的是同样的风。

And the other thing, the other important factor

还有另外一点，另外一个很重要的因素是

for all these birds, all medium sized fellows,

所有的这些鸟都是中等大小的家伙，

and this includes the next slide as well, which is a bee-eater.

这也包括在下面一张投影片上的鸟，这是一只食蜂鸟.

Bee-eaters eat bees. This one has a nice blue cheek.

食蜂鸟捕食蜜蜂。这种鸟有漂亮的蓝色脸颊，

It's a Blue-cheeked Bee-eater.

所以叫做蓝颊食蜂鸟。

And every one of these birds that makes the crossing

而且所有这些从印度飞越大洋到达东非的

from India to East Africa

鸟类

eats insects, large insects,

都捕食昆虫，大型昆虫，

the size of dragonflies. Thank you very much.

像蜻蜓那样大的。谢谢你们。

(Applause)

掌声