评论
打印
Coming up next on Jonathan Bird's Blue World, why do sharks hang out at shipwrecks?
接下来是乔纳森·伯德的《蓝色世界》，鲨鱼为什么会在沉船上出没？
The blue world keeps her secrets well,
蓝色大海一直保持着它的神秘，
and today we're going to attempt to solve a mystery about an amazing fish.
我们今天将要试图解开一种神奇之鱼的秘密。
Every spring, sand tiger sharks converge at certain shipwrecks off the coast of North Carolina.
每年春天，虎鲨都会聚集在北卡罗来纳海岸附近的一些沉船上。
Nobody knows why they visit these wrecks or what they like about them.
没有人知道它们为什么要参观这些沉船，或者它们喜欢沉船的什么。
They don't seem to be doing much of anything.
它们似乎什么都没做。
But scientists have a theory on what they are doing...
但是科学家们对它们的做法有一个理论，
and we're going to see if we can confirm it.
我们想看看能否证实它。
Hi, I'm Jonathan Bird and Welcome to my world!
嗨，我是乔纳森·伯德，欢迎来到我的世界！
Our adventure begins in coastal North Carolina in the United States.
我们从美国北卡罗来纳州的沿海地区开始冒险之旅。
We have loaded piles of gear aboard a dive boat
我们在一艘潜水船上装载了许多设备，
and we're heading way offshore to an area of the ocean full of World War 2 shipwrecks,
现在正离岸前往一个满是二战沉船的海域，
known as the "Graveyard of the Atlantic."
即“大西洋墓地”。
The wrecks are located here, in a lonely section of the open ocean, more than 10 miles from land.
大量沉船位于这里，一个公海上的偏僻之地，它离陆地有10英里远。
Eighty feet below this boat is the wreck of the Carib Sea, a ship that was sunk in World War 2 by a German U-boat.
这条船下面80英尺处是“Carib Sea”沉船，它在二战中被一艘德国潜艇击沉。
The Carib Sea has deteriorated over 60 years on the bottom of the ocean, but it still looks like a ship.
“Carib Sea”沉船在海底已经腐化60多年了，但它看起来仍像一条船。
My crew and I are suiting up to explore the wreck and the sharks that have come here.
我和我的船员们正在着装，准备探索这些沉船以及已经到了的鲨鱼。
We don our gear and jump into the water, descending down the anchor line into the blue.
我们穿上装备跳进水里，沿着锚线下降到海里。
What starts out as crystal clear water near the surface, becomes more murky at the bottom.
一开始地表附近是清水，到了底部水就变浑浊了。
Out of the haze, a shark slowly materializes, swimming at a leisurely pace.
一片模糊中，一条鲨鱼缓缓出现，悠闲地游着。
Sand Tigers have rows of pointy teeth that look pretty scary.
虎鲨有一排排尖尖的牙齿，看起来很吓人。
These needle-like teeth are not designed for biting divers,
这些针状牙齿不是用来咬潜水员的,
but in fact they are good for grabbing and holding on to slippery fish.
事实上，它们很适合抓捕滑溜溜的鱼。
They aren't good for cutting, so the sand tiger usually doesn't take bites out of anything.
它们不适合切东西，所以虎鲨通常不会把东西咬碎。
They usually don't eat anything that they can't swallow in one bite.
虎鲨通常不吃一口吞不下去的食物。
As I swim around looking at the sharks, they seem to be trying to act inconspicuous,
当我游来游去看那些鲨鱼时，它们似乎想表现得不那么显眼，
as if they are just waiting for me to leave so they can get back to what they are doing when I'm not around.
它们好像在等我离开，这样就能继续做我不在的时候做的事了。
But what are they doing when I'm not around?
但我不在的时候它们在做什么？
They could be coming to the wrecks to eat.
它们可能会来沉船这里吃东西。
After all, there are a lot of fish here. But there are a lot of fish in lots of places.
毕竟，这里有很多鱼。但很多地方都有很多鱼。
Why would all these sharks come to the wrecks in North Carolina all at the same time?
为什么这些鲨鱼会同时出现在北卡罗来纳州的沉船上呢？
Biologists think this is no coincidence.
生物学家认为这不是巧合。
They think the sharks come here to mate.
他们认为鲨鱼是来这里交配的。
One clue are the sharks teeth that can be found on the wreck.
一条线索是沉船里可以找到鲨鱼的牙齿。
As I look around, I find a bunch of shark's teeth scattered on the wreck and in the sand nearby.
我环顾四周，发现一堆鲨鱼的牙齿散落在沉船和附近的沙地上。
Sharks have a steady supply of new teeth being regenerated
鲨鱼能够稳定供应再生的新牙，
because they lose their teeth every once in while when they bite something.
因为它们咬东西的时候每隔一段时间就会掉牙。
When sharks mate, the male bites onto the female to hold on.
当鲨鱼交配时，雄鲨咬住雌鲨不放。
He often loses some teeth in the process.
在这个过程中它经常掉牙。
Scientists think these teeth are a sign that the sharks are mating at the wrecks!
科学家们认为这些牙齿是鲨鱼在沉船上交配的记号！
They sure aren't mating while we're around, even if we use our super-quiet rebreathers.
我们在周围时，它们肯定不会交配，即使我们用的是超安静的氧气呼吸器。
So the next step is to place some remote cameras on the wreck and leave,
所以下一步我们要在沉船上放置一些远程摄像机，然后离开，
to see if we can catch the sharks doing anything without us around.
看看我们不在旁边时，能不能拍到鲨鱼的活动。
My crew and I place several remote cameras on the shipwreck.
我和我的船员们在沉船上放了几个远程摄像机。
We will record for an hour with nobody around so that the sharks won't be disturbed by our presence.
我们会在周围没人的情况下录一个小时，这样鲨鱼就不会被我们打扰了。
Later we look at the tapes to see if the cameras caught anything.
之后我们再看录像，看看摄像机是否捕捉到了什么。
See now what's surprising me about this is that I really expected to see something different with the unmanned cameras.
现在让我惊讶的是，我真的很期待在无人操纵的相机上看到不同的东西。
I mean when we're not down there, there's no divers, they should be doing something now that we're not there.
我的意思是，当我们不在那里、没有潜水员的时候，它们现在应该在做点儿什么。
But they're doing the same thing, which is nothing!
但它们只做了一件事，那就是无所事事！
While we got some interesting shots of the sharks, we didn't see any mating.
尽管我们得到了一些有趣的鲨鱼照片，但我们没有看到任何交配活动。
In fact, they looked like they are doing the same exact thing they do when we are down there with them
事实上，它们正在做得事情似乎与我们在水下与它们一起时做得一样。
I would expect a lot more action.
我期待更多的动作。
Hmm, I think we are going to have to go back out and see what they do at night.
嗯，我觉得我们得回去看看它们晚上做什么。
I think that's the only thing we can see because if they're not doing it during the daytime,
如果它们不在白天做的话，我认为这是我们唯一能看到的活动，
maybe it's a nighttime, maybe it's a nocturnal activity.
也许它们在夜间活动。
Could the sharks be mating at night?
鲨鱼会在晚上交配吗？
There's only one way to find out, and it's a pretty spooky option.
只有一种方法可以找到答案，而且这个选择非常可怕。
We are the first film crew to attempt filming Sand Tigers on this wreck at night.
我们是第一个试图夜间拍摄这艘沉船上的虎鲨的摄制组。
