How do you save a shark you know nothing about? | Simon Berrow

48,400 views ・ 2012-02-16

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譯者: Ariel Zheng 審譯者: Wang-Ju Tsai
00:15
Basking sharks are awesome creatures.
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姥鯊是相當美妙的生物,真的非常不可思議
00:17
They are just magnificent.
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牠們身長足足有10公尺
00:19
They grow 10 meters long; some say bigger.
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也有人說比10公尺長
00:22
They might weigh up to two tons.
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體重達2噸
00:24
Some say up to five tons.
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也有人認為將近5噸
00:26
They're the second-largest fish in the world.
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牠們是全世界第二大的魚類
00:28
They're also harmless plankton-feeding animals.
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是以捕食浮游生物為主的無害動物
00:31
And they are thought to be able to filter a cubic kilometer of water every hour
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據說每小時
可以過濾1立方公里的海水
00:36
and can feed on 30 kilos of zoo plankton a day to survive.
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每天攝食高達30公斤的浮游動物
實在是太不可思議了
00:41
They're fantastic creatures.
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愛爾蘭有許多姥鯊
00:42
We're very lucky in Ireland,
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00:44
we have plenty of basking sharks and plenty of opportunities to study them.
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讓我們有幸能研究牠們
姥鯊對海洋生態社區也是相當重要的
00:47
They were very important to coastal communities,
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早在幾百年前
00:50
going back hundreds of years,
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特別在克拉達、達夫和康尼瑪拉地區
00:51
especially around the Claddaghduff, Connemara region
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獨立農夫會出海
00:54
where subsistence farmers used to sail out on their hookers and open boats,
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乘著漁船
00:57
sometimes way offshore to a place called the Sunfish Bank,
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出海到一個叫太陽魚淺灘的地方
大概離愛奇島48公里以西的位置
01:00
about 30 miles west of Achill Island,
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去捕殺姥鯊
01:02
to kill the basking sharks.
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01:03
This is a woodcut from about the 1800s.
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這是來自17, 18世紀的木版畫
因為姥鯊肝臟含很多肝油,所以當時地位非凡
01:06
They were very important, for the oil out of their liver.
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01:08
A third of the basking shark's size is their liver,
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肝臟占身體的1/3,滿滿是油
從牠們的肝臟就能提鍊出好幾加侖的肝油
01:11
and it's full of oil, gallons of oil.
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這些油當時主要供照明用途
01:13
That oil was used especially for lighting,
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除此之外也可用來治療傷口等等
01:15
but also for dressing wounds and other things.
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事實上,在1742年
01:17
In fact, the streetlights in 1742,
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戈爾韋、都柏林和沃特福的路燈
01:19
of Galway, Dublin and Waterford,
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01:20
were lit with sunfish oil.
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多多少少都跟太陽魚肝油有關
01:22
"Sunfish" is one of the words for basking sharks.
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姥鯊又叫「太陽魚」
01:24
So they were incredibly important animals.
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所以牠們算是相當重要的動物
01:26
They've been around a long time, very important to coastal communities.
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歷史久遠,對海洋生態社區也非常重要
擁有全世界最完整的姥鯊文獻紀錄的
01:30
Probably the best-documented basking shark fishery in the world
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就是愛奇島
01:33
is that from Achill Island.
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01:34
This is Keem Bay up in Achill Island.
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這是愛奇島的欽灣
以前鯊魚會在這裡出沒
01:37
Sharks used to come into the bay,
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01:39
and the fishermen would tie a net off the headland,
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漁夫就會把魚網掛在岬角上
01:42
string it out, an old Manila net,
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再展開和其他魚網連接
01:44
and as the shark came round, it would hit the net,
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鯊魚來了一觸碰到魚網,網子就會掉下來
01:46
the net would collapse on it.
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鯊魚就會因窒息而溺死
01:48
It would often drown and suffocate.
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01:49
Or at times, they would row out in their small curraghs
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有時候還會划小船出去
01:52
and kill it with a lance through the back of the neck.
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用魚叉往牠們背後戳
最後在一路將屍體拖回波庭港口
01:55
And then they'd tow the sharks back to Purteen Harbour,
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01:57
boil them up, use the oil.
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煮沸,再提練肝油
01:59
They also used the flesh as well, for fertilizer
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剩下來的肉也被用來當肥料
當然也會採割魚翅
02:03
and also would fin the sharks.
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02:06
This is probably the biggest threat to sharks worldwide --
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全球最大的鯊魚元兇
就是採割魚翅這個行為了
02:09
the finning of sharks.
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看過「大白鯊」這部電影的人都對鯊魚懷有恐懼之心
02:11
We're often frightened of sharks, thanks to "Jaws."
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每年大概有5-6人
02:13
Maybe five or six people get killed by sharks every year.
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死於鯊魚攻擊
前陣子不是就有人遇害?才幾個禮拜前而已
02:17
There was someone recently, wasn't there? Just a couple weeks ago.
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但我們每年捕殺1億條鯊魚
02:20
We kill about 100 million sharks a year.
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02:22
So I don't know what the balance is,
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真曉得天理何在
02:24
but I think sharks have more right to be fearful of us than we have of them.
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照理講,鯊魚應該要比較怕我們才對
這個獵捕行為紀錄完整
02:28
It was a well-documented fishery.
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02:29
As you can see here, it peaked in the '50s,
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從這裡可以看到,在50年代達到高峰
每年獵殺高達1500條鯊魚
02:32
where they were killing 1,500 sharks a year.
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接著急遽下降,這就是漁業大起大落的特性
02:34
And it declined very fast -- a classic boom-and-bust fishery,
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這就顯示鯊魚的數量已所剩無幾
02:37
which suggests that a stock has been depleted
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02:39
or there's low reproductive rates.
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不然就是繁殖率非常低
02:41
They killed about 12,000 sharks within this period,
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在這期間將近12,000隻鯊魚遭殺害
光是愛奇島的欽灣
02:44
literally just by stringing a Manila rope
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用馬尼拉繩捕殺的數量
02:47
off the tip of Keem Bay up in Achill Island.
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就這麼多了
02:50
Sharks were still killed up into the mid-80s,
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一直到80年代中期,獵鯊行為仍盛行
02:52
especially out of places like Dunmore East in County Waterford.
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尤其是在沃特福的鄧莫爾東郡地區
02:55
About two and a half, 3,000 sharks were killed up till '85,
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到1985年還是有2500到3000條鯊魚遭捕殺
02:58
mainly by Norwegian vessels.
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其中有很多是挪威的漁船
03:00
You can't really see,
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圖中黑色的船,這裡有點看不清楚,是挪威獵捕姥鯊的船隻
03:01
but these are Norwegian basking shark hunting vessels.
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瞭望臺上的黑線
03:04
The black line in the crow's nest signifies this is a shark vessel,
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表明這是一艘獵捕鯊魚的船
03:07
rather than a whaling vessel.
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而不是捕鯨船
03:09
The importance of basking sharks to the coast communities
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姥鯊在海洋生態社區占有的重要地位
03:12
is recognized through the language.
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體現在語言上
03:14
I don't pretend to [know many Irish words],
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我不想假裝自己很懂愛爾蘭語
03:16
but in Kerry they were often known as "ainmhide Na seolta,"
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不過在凱里郡,大家把姥鯊形容為「Ainmhide na seolta」
意指「帶帆的怪物」
03:20
"the monster with the sails."
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還有另一個稱號是「Liop an da lapa」
03:22
Another title would be "liop an dá lapa,"
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意思是「龐大笨重的兩鰭怪」
03:25
"the unwieldy beast with two fins."
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還有「Liabhan mor」,形容巨大的動物
03:28
"Liabhán mór," suggesting a big animal.
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還有我最愛的別名「Liabhan chor greine」
03:31
Or my favorite, "liabhán chor gréine," "the great fish of the sun."
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也就是「偉大的太陽魚」
03:34
That's a lovely, evocative name.
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還滿可愛又充滿聯想的名字
03:36
On Tory Island -- a strange place anyway -- they were known as "muldoons."
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托裏島上,反正那裡也滿奇怪的,姥鯊又叫「馬爾登」
03:39
(Laughter)
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沒有人知道為什麼
03:40
No one seems to know why.
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希望在座沒有來自托裏島的朋友,那裡很迷人
03:42
Hope there's no one from Tory here. Lovely place.
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不過最常用的別名
03:44
But more commonly all around the island, they were known as the sunfish.
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是太陽魚
03:48
And this represents their habit of basking on the surface
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這個名字最能代表牠們喜歡曬太陽的行為
03:51
when the sun is out.
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姥鯊在全球各地瀕臨絕種的現象
03:52
There's great concern that basking sharks are depleted
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03:54
all throughout the world.
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非常令人擔憂
03:56
Some say it's not population decline,
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有人認為這不是數量的減少
03:58
it might be a change in the distribution of plankton.
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可能是浮游生物分布情況改變了
04:00
It's been suggested
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也有人認為姥鯊數量的減少
04:02
that these sharks would make fantastic indicators of climate change,
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是反映溫室效應的指標
因為牠們最能反映浮游生物的狀況
04:05
as they're basically continuous plankton recorders,
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成天嘴巴開開游來游去的
04:07
swimming around with their mouth open.
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國際自然保護聯盟已將姥鯊列為「瀕危」狀態
04:09
They're now listed as vulnerable under the IUCN.
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歐洲各國也正嘗試採取行動停止獵捕活動
04:12
There's movements in Europe to try and stop catching them.
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現在已立法禁止捕捉姥鯊,甚至禁止讓牠們上岸
04:15
There's now a ban on catching and even landing them,
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04:17
even landing ones caught accidentally.
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就連意外捕捉到的也不行
04:19
They're not protected in Ireland;
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然而,愛爾蘭卻沒有保護姥鯊
04:21
in fact, they have no legislative status in Ireland whatsoever,
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事實上,愛爾蘭完全沒有相關禁止的法律條文
儘管我們知道姥鯊有多重要
04:24
despite our importance for the species
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以及牠們賴以生存的歷史意義
04:26
and also the historical context within which basking sharks reside.
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04:29
We know very little about them.
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我們對姥鯊的了解甚少
04:31
And most of what we do know
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所了解最多的
04:33
is based on their habit of coming to the surface --
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也只能從牠們喜愛浮出水面的習慣下手
然後試著揣測她們的行為
04:36
we try and guess what they're doing from their behavior on the surface.
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從牠們在水面上的行為來猜測
04:39
I only found out last year, at a conference on the Isle of Man,
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我一直要到去年一場在曼島的會議中
04:42
just how unusual it is to live somewhere
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才意識到,住在一個
04:45
where basking sharks regularly, frequently and predictably
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姥鯊經常固定浮出水面來曬太陽的地方
是多麼難得
04:49
come to the surface to "bask."
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這對科學研究來說,能親眼看到姥鯊
04:51
It's a fantastic opportunity for a scientist
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實在是相當可貴
04:54
to see and experience basking sharks.
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牠們真的是非常不可思議的生物
04:55
They are awesome creatures.
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住在這裡,使我們可以實際研究、接近牠們
04:57
It gives us a fantastic opportunity to study them, to get access to them.
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我們好幾年來在做的事--去年對我們來說滿重大的
05:00
What we've been doing for a couple years -- last year was a big year --
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我們開始標幟鯊魚
05:04
is we started tagging sharks,
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這樣才能追蹤
05:06
so we could try to get some idea of sight fidelity and movement
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牠們的動態以及棲地忠實性
05:09
and things like that.
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我們主要集中在
05:10
So we concentrated mainly in North Donegal and West Kerry
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登內加爾北部和凱里郡西部
05:13
as the two areas where I was mainly active.
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這兩個區塊我比較熟悉
05:16
And we tagged them very simply, not very high-tech,
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我們標識的方法非常簡單又有點土法煉鋼
是用一個又大又長的竿子
05:20
with a big, long pole.
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這是一個beachcaster牌的竿子
05:21
This is a beachcaster rod with a tag on the end.
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在尾端有標幟
05:24
You go up in your boat and tag the shark.
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就到船上標幟鯊魚
05:27
And we were very effective.
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我們相當有效率
05:29
We tagged 105 sharks last summer.
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去年夏天就標了105條鯊魚
三天內就在印尼豪恩半島
05:32
We got 50 in three days off Inishowen Peninsula.
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標了50條鯊魚
05:35
Half the challenge to get access
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主要是抓準時間,也要抓對地點
05:37
is to be in the right place at the right time.
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不過這是一個非常簡單的技術
05:39
But it's a very simple, easy technique; I'll show you what it looks like.
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來給大家看牠們的樣子
我們在船上使用竿子上的相機
05:43
We use a pole camera on the boat to actually film the shark.
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來拍攝鯊魚
05:46
One, it's to try and work out the gender of the shark.
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首先要分辨鯊魚的性別
05:48
We also deployed some satellite tags, so we did use high-tech stuff as well.
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我們也用了一些衛星標,所以也有運用到高科技產品
這些是衛星檔案標幟
05:52
These are archival tags.
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05:53
What they do is store the data.
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可以儲存資料
05:55
A satellite tag only works when the air is clear of the water
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衛星標只能在接觸空氣並沒有水的狀況下
才能使用並發送訊號給衛星
05:58
and can send a signal to the satellite.
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當然,鯊魚和魚類大部份的時間都在水裡
06:00
And sharks and fish are underwater most of the time,
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所以這個標幟會根據時間和太陽的升降
06:03
so this tag actually works out the locations of shark,
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06:05
depending on the timing and the setting of the sun,
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來推斷鯊魚的位置
其中也會考量海水的溫度和深淺
06:09
plus water temperature and depth.
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我們必須根據收集的資料重建路線
06:11
And you have to kind of reconstruct the path.
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06:13
What happens is,
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要設定讓標幟在一定的時間後自動脫落
06:14
you set the tag to detach from the shark after a fixed period --
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我們的設定是八個月
06:17
in this case, eight months --
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時間到了,標幟會浮出水面,傳資料給衛星
06:19
and literally to the day, the tag popped off,
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06:21
drifted up, said hello to the satellite
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而且並不是全部的資料,而是讓我們足以使用的資料
06:23
and sent, not all the data, but enough data for us to use.
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這是唯一可以摸透
06:26
This is the only way to really work out their behavior and movements
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牠們在水裡行為的辦法
06:29
when they're underwater.
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這邊是我們做的一些地圖
06:31
And here's a couple of maps that we've done.
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06:33
In that one, you can see that we tagged both off Kerry.
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可以看到兩個都在凱里郡標幟到鯊魚
06:36
Basically, it spent all its time, the last eight months, in Irish waters.
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基本上牠在過去八個月都在愛爾蘭海域活動
聖誕節跑到棚緣
06:40
On Christmas, it was out on the shelf edge.
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這個我們還沒實地勘察
06:42
Here's one we haven't ground-truthed yet
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海面溫度及水深
06:44
with sea-surface temperature and water depth,
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不過,第二隻鯊魚大部份時間
06:46
but again, the second shark spent most of its time
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也在愛爾蘭海域活動
06:48
in and around the Irish Sea.
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去年有一位曼島的同事
06:50
Colleagues from the Isle of Man last year actually tagged one shark
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標到一隻鯊魚
06:53
that went from the Isle of Man to Nova Scotia in about 90 days.
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在90天以內從曼島跑到加拿大的新斯科舍省去
06:56
Nine and a half thousand kilometers -- we never thought that happened.
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距離有9500公里,相當驚人
還有另一個美國的同事
07:00
Another colleague in the States tagged about 20 sharks off Massachusetts.
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在麻省標了大概20隻鯊魚,他的標幟有點故障
07:03
His tags didn't really work.
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只知道標幟的地點
07:05
All he knows is where he tagged them,
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和最後浮出來的位置
07:07
and where they popped off.
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07:08
His tags popped off in the Caribbean,
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結果他的標幟竟出現在加勒比海
甚至在巴西
07:11
and even in Brazil.
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07:12
We thought basking sharks were temperate animals
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我們以為姥鯊是溫帶動物
07:14
and lived in our latitudes,
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只能在我們這裡的緯度生存
07:16
but in actual fact, they're obviously crossing the equator as well.
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不過事實上,牠們很明顯也會到赤道地區
07:19
So very simple things like that,
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所以我們就是企圖瞭解姥鯊的
07:21
we're trying to learn about basking sharks.
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這些簡單的事情
我發現
07:24
One thing that I think is a very surprising and strange thing
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有一件非常奇特的現象
07:28
is just how low the genetic diversity of sharks is.
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就是鯊魚的基因多樣性很低
07:31
I'm not a geneticist, so I won't pretend to understand the genetics.
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我不是基因學家,也沒有要假裝自己很懂基因學
這時候跟別人合作就很棒
07:35
And that's why it's great to have collaboration.
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07:37
Whereas I'm a field person,
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我擅長田野調查
07:39
I get panic attacks
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如果要我在實驗室待好幾小時
07:40
if I have to spend too many hours in a lab with a white coat on.
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我就會瘋掉
07:43
Take me away.
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這時候就可以和擅長這塊的基因學家合作
07:45
So we can work with geneticists who understand that.
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07:47
So when they looked at the genetics of basking sharks,
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當他們觀察姥鯊的基因
就發現基因多樣性極低
07:50
they found that the diversity was incredibly low.
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你看看第一條線
07:53
If you look at the first line, really,
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就可以看到這些不同種類的鯊魚長得滿相近的
07:55
you can see that all these different shark species are all quite similar.
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這大概就表示牠們都是鯊魚
07:58
I think this means they're all sharks
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且來自相同的祖先
08:00
and they've come from a common ancestry.
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如果觀察核苷酸多樣性
08:02
But if you look at nucleotide diversity,
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08:04
which is more genetics that are passed on through the parents,
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也就是由父母傳下來的基因
08:07
you see that basking sharks, if you look at the first study,
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會發現姥鯊,看第一份報告
08:10
was order of magnitude less diverse even than other shark species.
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多樣性
比其他鯊魚種類還低
08:14
You can see this work was only done in 2006.
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這份研究在2006年完成
08:16
Before 2006, we had no idea of the genetic variability of basking sharks.
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在2006年之前,我們對姥鯊的基因多樣性毫無概念
我們不知道牠們是否分散為不同的族群?
08:20
We had no idea: Did they distinguish into different populations?
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那麼次族群又在哪裡?
08:23
Were there subpopulations?
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08:24
And that's very important if you want to know
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這是很重要的資訊
也就是動物的族群及現況
08:27
what the population size is, and the status of the animals.
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08:29
So, Les Noble in Aberdeen kind of found this a bit unbelievable, really.
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英國阿伯丁大學的諾柏
覺得這相當不可思議
08:33
So he did another study using microsatellites,
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於是他做了另一項研究
並使用微衛星
微衛星更貴又更費時間
08:40
which is much more expensive, much more time-consuming,
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08:42
and to his surprise, came up with almost identical results.
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最後結果卻幾乎一模一樣
08:45
So it does seem to be that basking sharks, for some reason,
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2912
所以看起來
姥鯊的基因多樣性確實極低
08:48
have incredibly low diversity.
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1770
08:50
And it's thought maybe it was a genetic bottleneck,
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也許這是一個瓶頸,一個基因上的瓶頸
可能在12,000年前
08:53
thought to have been 12,000 years ago,
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造成了非常低的多樣性
08:55
and this has caused a very low diversity.
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08:57
And yet, if you look at the whale shark,
208
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1960
不過你看豆腐鯊
08:59
which is the other plankton-eating large shark,
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另一個以浮游生物為食的大型鯊魚
09:02
its diversity is much greater.
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多樣性就高很多
09:04
So it doesn't really make sense at all.
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這實在是沒道理
09:06
They found that there was no genetic differentiation
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他們發現在世界上的姥鯊
沒有基因上的差別
09:09
between any of the world's oceans of basking sharks:
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2461
09:11
even though they're found throughout the world,
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即使姥鯊分布在世界各地
09:13
you couldn't tell the difference, genetically,
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在基因上卻沒有差別
09:15
from one from the Pacific, Atlantic, New Zealand, Ireland, South Africa.
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不管是大西洋、太平洋、紐西蘭、愛爾蘭或南非
牠們基本上都一樣
09:19
They all basically seem the same.
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這也是相當驚人的發現,很令人感到意外
09:21
Which, again, is kind of surprising; you wouldn't expect that.
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09:23
I don't understand or pretend to understand this;
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我不懂,也不假裝懂
我想大部份的基因學家也感到不解
09:26
I suspect most geneticists don't either,
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不過他們會產生數據
09:28
but they produce the numbers.
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09:29
So you can actually estimate the population size
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所以你可以根據基因多樣性
推算族群的數量
09:32
based on the diversity of the genetics.
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羅斯荷澤計算出相當準確的數字
09:34
And Rus Hoelzel came up with an effective population size:
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一共有8200隻
09:37
8,200 animals.
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就這樣
09:39
That's it -- 8,000 animals in the world.
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世界上就只有八千隻
09:42
You're thinking, "That's ridiculous. No way."
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你一定會覺得「這太扯了,不可能」
09:44
So Les did a finer study,
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不過諾柏做了更精確的研究
09:46
and he found out it came out about 9,000.
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結果數字大概落在9000
使用不同的微衛星得到不同結果
09:49
Using different microsatellites gave the different results,
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不過所有的研究平均出來--
09:52
but the mean of all these studies is about 5,000,
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平均數為5000
我個人不相信這份報告結果
09:57
which I personally don't believe.
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09:58
But then, I am a skeptic.
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不過我這個人一向就會抱持懷疑的態度
10:00
But even if you toss a few numbers around,
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但就算你把數字換一換
10:02
you're probably talking an effective population of about 20,000 animals.
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有效的族群數字也大概在20,000隻
記不記得70年代和50年代
10:06
Do you remember how many they killed off Achill in the 70s and the 50s?
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我們在阿基爾島殺了多少隻鯊魚?
10:10
So what it tells us, actually,
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所以這個數據其實是要告訴我們
10:12
is that there's actually a risk of extinction of this species
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這個種類面臨絕種的危機
10:15
because its population is so small.
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因為牠們的族群很小
10:17
In fact, of those 20,000,
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事實上,在那20,000當中,其中只有8000隻是母的
10:19
8,000 were thought to be females.
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全世界就只有8000隻母姥鯊?
10:21
There's only 8,000 basking shark females in the world?
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我不知道,我不相信
10:24
I don't know. I don't believe it.
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問題在於
10:26
The problem with this is they were constrained with samples.
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基因學家受困於樣本
他們沒有足夠的樣本
10:30
They didn't get enough samples
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10:31
to really explore the genetics in enough detail.
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來仔細
去研究這些基因
10:35
So, where do you get samples from for your genetic analysis?
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那到底要從哪裡
去蒐集到需要的基因樣本呢?
10:40
Well, one obvious source is dead sharks --
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一個滿明顯的來源就是死掉的鯊魚
沖上岸的死鯊魚
10:43
dead sharks, washed up.
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愛爾蘭每年大概會有2-3隻死鯊魚被沖上岸
10:45
We might get two or three dead sharks washed up in Ireland a year,
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假如我們幸運的話
10:48
if we're kind of lucky.
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1522
10:49
Another source would be fisheries' bycatch.
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2350
另一個來源就是漁業混獲
我們在海洋漂網中捕獲過蠻多條姥鯊的
10:52
We were getting quite a few caught in surface drift nets.
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此活動現在已立法禁止,這對鯊魚是個好消息
10:55
That's banned now, and that'll be good news for the sharks.
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還有一些是由魚網、拖網捕捉到的
10:58
And some are caught in nets, in trawls.
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1917
10:59
This is a shark that was actually landed in Howth just before Christmas --
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3618
這一條是在聖誕節都柏林的后斯地區非法捕到的
因為歐盟法律已禁止這種行為
11:03
illegally, because you're not allowed to do that under EU law --
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3027
在這之前,鯊魚肉事實上是以一公斤8歐元的價錢賣出
11:06
and was actually sold for eight euros a kilo as shark steak.
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2838
在牆上還會有食譜教你怎麼烹煮鯊魚煙
11:09
They even put a recipe up on the wall,
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1824
11:11
until they were told it was illegal.
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1778
這些人後來有被罰錢
11:13
They actually did get a fine for that.
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1879
那麼如果看這些研究報告
11:15
So if you look at all those studies I showed you,
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全世界的樣本總數
11:17
the total number of samples worldwide
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2656
為86條
11:20
is 86, at present.
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1524
可見這是非常重要的工作
11:22
So it's very important work,
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2092
也可以從中發現很重要的問題
11:24
and they can ask some really good questions,
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2095
這些報告能顯示族群大小
11:26
and tell us about population size and subpopulations and structure,
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亞群數量及其結構
11:30
but they're constrained by lack of samples.
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不過因樣本數的不足而導致研究受限制
我們出海標鯊魚時
11:34
When we were out tagging our sharks --
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1849
11:35
this is how we tagged them on the front of a RIB, get in there fast --
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3310
這是我們標鯊魚肋骨的方法-動作迅速-
有時候鯊魚也會反抗
11:39
occasionally, the sharks do react.
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有一次我們在多尼戈爾的馬林角地區
11:41
On one occasion, when we were up in Malin Head in Donegal,
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一隻鯊魚用牠的尾鰭衝撞船的側身
11:44
the shark smacked the side of the boat with his tail,
273
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2498
11:46
more, I think, in startle to the fact that a boat came near it,
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3144
我想是因為船離牠很近而受驚
11:49
rather than the tag going in.
275
709866
1986
而不是因為我們要作標幟
但那沒關係,只不過是淋溼了而已
11:52
And that was fine. We got wet. No problem.
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還有一次我跟艾密特
11:55
And then when myself and Emmett got back to Malin Head, to the pier,
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3990
要回馬林頭碼頭
我注意到船前有黑色的黏液
11:59
I noticed some black slime on the front of the boat.
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719150
2442
12:01
I used to spend a lot of time on commercial fishing boats,
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2729
這時我就想起-我以前待過漁船-
我記得漁夫告訴我
12:04
and I remember fishermen saying
280
724369
1479
12:05
they can tell when a basking shark has been caught in a net,
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2823
只要魚網裡有姥鯊
就會留下黑色的黏液
12:08
because it leaves a black slime behind.
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1880
所以我就心想那一定是姥鯊留下來的黏液
12:10
So that must have come from the shark.
283
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1831
我們一直想
12:12
Now, we had an interest in getting tissue samples for genetics
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3394
取得組織樣本來作基因研究
12:15
because we knew they were very valuable.
285
735896
1986
因為這些樣本非常寶貴
12:17
We would use conventional methods;
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1657
我們會用傳統方法
12:19
I have a crossbow -- you see it in my hand there,
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2317
我會拿一個石弓,在這裡會看到我手中的石弓
12:21
which we use to sample whales and dolphins for genetic studies as well.
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3486
我們也會用這個來取鯨魚及海豚樣本來作基因研究
我就試了那個方法,試遍各種方法
12:25
So I tried that, I tried many techniques.
289
745438
1975
但結果石弓都斷了
12:27
All it was doing was breaking my arrows,
290
747437
1929
因為鯊魚的皮太硬
12:29
because the shark's skin is just so strong.
291
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2025
想用這種方法取樣本是不可能的
12:31
There was no way we were going to get a sample from that.
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2776
那是行不通的
12:34
That wasn't going to work.
293
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1577
12:35
So when I saw the black slime on the bow of the boat,
294
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2557
所以當我看到船前的黑色黏液
12:38
I thought, "If you take what you're given in this world ..."
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2977
我就想「何不拿這個現成的東西...」
12:41
So I scraped it off.
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1164
我就把黏液刮下來
12:42
I had a little tube with alcohol in it to send to the geneticists.
297
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4395
然後跟酒精一起裝在一個小試管裡送去給基因學家
我把黏液刮下送去阿伯丁
12:47
So I scraped the slime off and sent it to Aberdeen,
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3055
我就說「可以試試這個」
12:50
and said, "You might try that."
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1516
於是他們研究好幾個月
12:51
And they sat on it for months.
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因為我們在曼島有個會議
12:53
It was only because we had a conference on the Isle of Man.
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2812
我就不斷寄信問
12:56
But I kept emailing Les, saying,
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1539
「你有抽空檢查我的黏液了嗎?」
12:57
"Have you had a chance to look at my slime?"
303
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2095
他就會敷衍回答「有啦,晚一點」
12:59
And he was like, "Yeah, yeah. Later."
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1843
後來他就著手去做了
13:01
He thought he'd better do it because I never met him before;
305
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2823
因為我們未曾見面
13:04
he might lose face if he hadn't done the thing I sent him.
306
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2755
所以如果沒有幫我看就很丟臉
結果他竟然在黏液中真的找到基因了
13:07
And he was amazed that they actually got DNA from the slime.
307
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2851
於是就把基因放大拿去作實驗
13:10
They amplified it and they tested it,
308
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1835
實驗結果發現這就是姥鯊的基因
13:12
and they found, yes, this was actually basking shark DNA,
309
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2798
而且是從黏液中取得的
13:14
which was got from the slime.
310
794849
1937
於是他就非常興奮
13:17
So he was very excited.
311
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1165
後來就有「賽門的鯊魚黏液」之稱
13:19
It became known as "Simon's shark slime."
312
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3285
我當時就想「我搞不好可以從這裡出發」
13:22
And I thought, "Hey, you know, I can build on this."
313
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2891
我就想我們何不出去
13:25
So we thought, OK, we're going to try to get out and get some slime.
314
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3762
蒐集夠多黏液
所以我們標了3500個衛星標
13:29
So having spent three-and-a-half thousand on satellite tags ...
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3634
我又投資了7.95元在這個上面-連價錢都還在上面-
13:35
I then thought I'd invest 7.95 -- the price is still on it --
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3437
就在基爾拉什當地的五金行
13:38
in my local hardware store in Kilrush
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2190
13:40
for a mop handle,
318
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1770
買了這個拖把柄
13:42
and even less money on some oven cleaners.
319
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2920
甚至花更少的錢買一些烤箱清潔刷
13:45
And I wrapped the oven cleaner around the edge of the mop handle
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我就把清潔刷包在拖把柄的尾端
就迫不及待地
13:49
and ...
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13:50
(Laughter)
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要找到機會
13:52
I was desperate to have an opportunity to get some sharks.
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標鯊魚
13:55
And this was into August now, and normally sharks peak in June, July,
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當時正要進入八月
鯊魚出現的高峰通常在六、七月
其他時間都很少看到
14:00
and you rarely see them, or rarely can be in the right place
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八月就很難抓準鯊魚出沒的時間地點
14:03
to find sharks into August.
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14:04
We were desperate, so we rushed out to the Blaskets
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所以我們相當急迫
一聽到有鯊魚出沒就匆忙趕到布拉斯克島
14:07
as soon as we heard there were sharks there,
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14:09
and managed to find some sharks.
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找到那些鯊魚
14:10
So by just rubbing the mop handle down the shark
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所以我們只不過是把拖把柄
摩擦這些在船下游動的鯊魚
14:14
as it swam under the boat --
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14:15
you see a shark running under the boat here --
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這邊可以看到船底下有鯊魚在那邊游
我們就成功取得黏液
14:18
we managed to collect slime.
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14:19
And here it is.
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就是這個
14:21
Look at that lovely black shark slime.
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非常美妙的黑色鯊魚黏液
14:24
And in about half an hour, we got five samples.
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在半小時內
我們蒐集了五個樣本,五個不同鯊魚的樣本
14:29
Five individual sharks were sampled
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而且是利用賽門的鯊魚黏液樣本系統
14:31
using Simon's Shark Slime Sampling System.
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(笑聲)
14:34
(Laughter)
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14:35
(Applause)
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(掌聲)
我在愛爾蘭研究鯨魚和海豚已有20年之久
14:41
I've been working on whales and dolphins in Ireland for 20 years now,
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牠們算是比較戲劇化的種類
14:44
and they're a bit more dramatic.
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各位大概看過座頭鯨的精彩鏡頭
14:46
You probably saw the humpback whale footage
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是我們一、兩個月前在韋克斯福德郡拍到的
14:48
we got a month or two ago off County Wexford.
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我們總是想在這世界上留名
14:50
And you always think you might have some legacy
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14:52
you can leave the world behind,
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而我一直在擔心這些座頭鯨
14:54
and I was thinking of humpback whales breaching and dolphins.
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和海豚遭殺害
不過有時候就是會有一些小東西自動送上門來
14:57
But hey -- sometimes these things are sent to you
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你就只能乖乖接收了
14:59
and you just have to take them when they come.
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這可能會是我遺留給這世界的遺產吧
15:01
So this is possibly going to be my legacy --
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賽門的鯊魚黏液
15:03
Simon's Shark Slime.
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而我們今年籌得更多資金
15:05
We got more money this year
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去蒐集更多樣本
15:07
to carry on collecting more and more samples.
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15:09
One thing that is very useful is that we use a pole camera --
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有個非常有用的東西
我們使用高竿攝影-這是我的同事裘安拿著高竿攝影機-
15:12
this is my colleague, Joanne, with a pole camera --
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就可以從鯊魚下方觀察牠們
15:15
where you can look underneath the shark.
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雄姥鯊有鰭腳(生殖器官)
15:17
What you're trying to look at is, the males have claspers,
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是一個長在姥鯊背後的垂狀物
15:20
which kind of dangle out behind the back of the shark.
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15:22
So you can quite easily tell the gender of the shark.
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這樣就可以輕易分辨姥鯊的性別
在取得樣本前
15:25
If we can tell the gender of the shark before we sample it,
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一旦先辨認出性別
我們就可以告訴基因學家,這樣本的雌雄
15:29
we can tell the geneticist this was taken from a male or a female.
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因為目前基因學家是無法從基因中
15:32
Because in the moment, they have no way, genetically,
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辨認出雌雄
15:34
of telling the difference between a male and a female,
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這是非常令人驚訝的消息
15:37
which I find staggering,
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因為他們不知道要去找哪些引子
15:38
because they don't know what primers to look for.
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能分辨出鯊魚的性別
15:41
Being able to tell the gender of a shark
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對立法禁止
15:43
is very important for things like policing the trade
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姥鯊及其他種類的鯊魚交易
15:47
in basking shark and other species through the sightings,
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是非常重要的
因為任何鯊魚的買賣都是違法的
15:52
because it is illegal to trade in these sharks.
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但市場上仍有鯊魚買賣行為
15:54
And they are caught and are on the market.
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所以身為田野生物學家
15:56
So as a field biologist,
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15:57
you just want to get encounters with these animals,
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就是要和這些動物接觸
並盡全力研究牠們
16:00
and learn as much as you can.
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16:01
They're often quite brief, they're often very seasonally constrained.
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牠們受季節影響出現時間很短
所以就更要把握機會作研究
16:05
You just want to learn as much as you can as soon as you can.
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這是非常美妙的事情
16:08
But isn't it fantastic
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16:09
that you can then offer these samples and opportunities
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我們可以提供這些樣本
給基因學家等人
16:13
to other disciplines, such as the geneticists,
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這些學者可以從中受益無窮
16:16
who can gain so much more from that.
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16:18
So as I said, these things are sent to you in strange ways.
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所以就像我稍早所說的
有時候機會會自動上門來,你就要把握機會
16:22
Grab them while you can.
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16:23
I'll take that as my scientific legacy.
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我會把這個當作我的科學遺產
16:25
Hopefully, I might get something a bit more dramatic and romantic
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不過也希望在我死前可以得到更戲劇化或更浪漫的東西
16:28
before I die.
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在這之前,就謝謝各位
16:30
But for the time being, thank you for that.
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記得多關注鯊魚
16:32
And keep an eye out for sharks.
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16:33
If you're more interested, we have a basking shark website now set up.
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如果有興趣的話,我們也剛架了一個關於姥鯊的網站
謝謝各位的聆聽
16:37
So thank you and thank you for listening.
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16:39
(Applause)
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(掌聲)
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