First, they've been around since the late Jurassic,

第一，牠們自侏羅紀末就出現在這個世界

Cohorts of the dinosaurs, sea turtles have survived through the challenges of eons,

身為恐龍的同伴，海龜倖存下來，並存活了長達億年

existing still today, where many others have ended their evolutionary run.

存活至今日，反觀牠的同伴卻結束了演化的旅程

Second, throughout the centuries and up til today,

第二，在過去幾個世紀直到今天

every living adult sea turtle has overcome the odds,

每隻成功存活的成年海龜都克服了難關

牠們的存活總歸機運、技能、及能力

The gauntlet each sea turtle faces in the course of its lifetime goes thus:

每隻海龜在牠一生中面臨的挑戰有：

First, deposited as a clutch of leathery, ping pong ball-sized eggs

首先，海龜媽媽於海灘高處挖出的窩裡

into a nesting pit dug by its mother high on the beach,

產下一窩革質、乒乓球大小的蛋

Roughly a month and a half after having been laid,

and the young turtles, each small enough to fit in the palm of your hand,

成為小海龜，每隻比你的手掌要來得小

Squirm to the surface, emerging from the sand en masse

and making their desperate dash for the sea.

一路走來，碎片、 坑洞、 螃蟹、

會奪走大約 50% 從沙裡爬出的小海龜的生命

they trade one set of threats for another,

as they first face the repelling force of the waves,

and then find a whole new host of predators awaiting them.

然後發現新的獵食者正等待著他們

various fish, dolphins, sharks and sea birds,

as the young turtles come to the surface for air.

還有當他們浮出水面呼吸所遇上的海鳥

should they count themselves amongst the living,

the vulnerable turtles swim frantically forward.

Ultimately, they will often look to settle in a patch of flotsam.

最後，牠們往往會在一團漂浮物下定居

Now, for the next several months, they will seek to avoid those that would eat them.

接下來幾個月，牠們會設法避開天敵

find that which they might eat themselves,

and not fall to the pressures of challenging weather or unfortunate currents.

並不被惡劣的天氣或海洋的亂流所擊倒

In this phase, roughly 50 percent of those who reach the surf

在此階段，大約 50% 進入海洋的海龜會死亡

在此階段，大約 50%進入海洋的海龜會死亡

from that of a dinner plate at year one to that of a dinner table,

體型從第一年的盤子大小，變成餐桌大小

in the case of one species at least, the Leatherback,

舉棱皮龜為例，過程可能需要十年以上

With size comes some measure of protection.

體型變大會帶來一些保護的功用

The only truly worrisome predators now are some of the larger shark species --

現在唯一令牠擔憂的掠食者是一些較大的鯊魚：

the survivors will be old enough themselves to breed,

存活下來的海龜將成熟到有繁殖能力

and continue the cycle which their very existence heralds.

繁衍下一代，見證生命週期的循環

Of those that began as eggs on a distant beach,

at least, those were the odds prior to significant human interference.

至少那是於人類破壞之前的機率

Over the past century, and in particular in the last several decades,

在過去這世紀，特別是在過去的幾十年裡

to plastic refuse to poaching, long lines, nets,

塑膠垃圾、盜獵、延繩釣、網捕、

and even noxious chemicals, including oil,

causing their survival rate to drop to around one percent or less

導致每一代新生海龜的存活率下降到

It is this added human pressure which has pushed each of the eight sea turtle species

人類所施加的生存壓力讓世界上的八種海龜

to either a threatened or endangered state.

都處於受威脅甚至瀕臨絕種的狀態

For while they have evolved to overcome a host of obstacles,

雖然演化天擇使牠們能夠克服種種障礙

and at such scale that the species find themselves

So let's quickly recap this cycle of odds.

現在，讓我們快速回顧海龜在一生中存活的機率

for females may nest multiple times in a single year,

因為母龜可以在一年中多次產卵

為了方便假設牠一次產下 1,000 顆卵

Twenty survive to breeding age -- that is, without human interference.

20 隻活到繁殖年齡──這是沒有人為干預的結果

Two survive to breeding age with human interference.

在人為干擾下，只有兩隻會活到繁殖年齡

So a breeding adult sea turtle is the very embodiment

of a longshot. It is the exception, not the rule.

不可能事件的化身。牠是個例外，不是常態

就像頭獎一樣，牠真的是一個奇蹟

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