coming up next on Jonathan Birds blue world
接下来是乔纳森·伯德的蓝色世界
Jonathan investigates the world's largest rays
乔纳森调查了世界上最大的鳐鱼
I've come to Yap in Micronesia famous for its huge stone money and its giant manta rays
我来到密克罗尼西亚的雅浦，那里以巨大的雅浦岛石币和蝠鲼而著称
hi I'm Jonathan bird and welcome to my world
大家好，我是乔纳森·伯德，欢迎来到我的世界
the app is a remote island in the Pacific about halfway between Japan and Australia
此地位于日本和澳大利亚之间太平洋上一个偏远的岛屿
divers travel here from all over the world to see an amazing and huge animal
世界各地的潜水员来到这里，观赏这神奇而巨大的动物
I'm talking about manta rays the largest Ray's in the world and they should be right under the boat
我说的是蝠鲼，它是世界上最大的鳐鱼，它们应该就在船的下面
let's go take a look as I drop into the water, I noticed that it's pretty murky
让我们下水去看个究竟，当我跳入水中，发现水很浑浊
I'm diving in a channel through the fringing reef between the open ocean and the land
我正在通过公海与陆地之间的暗礁潜入河道
as the tide changes water flows in and out of this channel
随着潮涨潮落
the current is moving me along rapidly
水流正迅速向我涌来，
and I ride it like a river following my guide John to a section of reef where we hope to find mantas
我好似乘着河水在向导约翰的带领下来到一段暗礁，我们希望能在那里找到蝠鲼
I tuck into a position at the base of a coral head out of the current and wait
我在激流珊瑚岬底部的一个位置等待着
the swift current blows the coral polyps like wind
湍急的水流宛若疾风，吹动着珊瑚虫
and sweeps along pieces of yield grass and mangrove leaves from the lagoon
还有那泻湖上的颗颗青草和片片红叶
I wait a long time it takes nearly an hour
我等了很长时间，将近一个小时
but finally a shape emerges from the murky distance
最终远处隐隐约约浮现一个身形
I would recognize that shape anywhere the beautiful and graceful motion of a manta ray
我在任何地方都能认出它，蝠鲼

soaring like a huge bird through the water
它像只巨鸟在水中翱翔
it stops over the Coral
停在珊瑚之上
a dozen or so tiny fish converge on the Ray while it hovers just over their home
蝠鲼在上空不断徘徊，十几条小鱼聚集在上面

the fish are cleaner wrasses they pluck parasites from the Rays
这些鱼属于清洁工濑鱼，它们从蝠鲼身上采集寄生虫
and this coral head is known as a cleaning station
这个珊瑚岬被称为清洁站
it's a great symbiotic relationship
清洁鱼和蝠鲼处于一种良好的共生关系
because both the fish and the Rays benefit from it
二者都能从中受益
the fish get a meal of tasty parasites like copepods and scraps of dead skin
鱼可以吃到美味的寄生虫，比如桡足类和死皮
while the manta ray gets rid of parasitic annoyances that can cause infection
而蝠鲼能消除引起感染的寄生虫病gct!45+9pW0。
cleaning is not always a pleasant experience though
不过，清洁并不总是很愉快
sometimes one of the cleaner fish nibbles a little too hard
有时候，清洁鱼咬得太用力
and the Manta jumps away
蝠鲼就会跳开
at the end of my dive I do a short decompression stop for safety then head up
潜水结束时，为了安全起见，我停下来做了一个短暂的减压，然后抬头
it's no coincidence that the mantas like a little bit of current while they're being cleaned
蝠鲼在清洁时喜欢些许的激流，这并不是巧合
mantas like all rays and sharks have no swim bladder
和鳐鱼、鲨鱼一样，蝠鲼也没有鱼鳔
a bony fish can hover in mid water perfectly still because it has a swim bladder to control its buoyancy
骨鱼类可以在水中完全静止，因为鱼鳔可以帮助控制浮力
sharks and rays sink if they stop swimming
鲨鱼和蝠鲼一旦停止游动就会下沉
the enormous wings of the Manta reaching 25 feet across allow them to fly through the water like a bird
蝠鲼的巨翼有25英尺宽，使得蝠鲼可以像鸟一样在水中飞行
and like a bird if they stop flapping they'll begin to glide towards the bottom
蝠鲼如果停止拍打翅膀，就会开始滑翔到水底，像鸟儿一样
the mantas come to the cleaning station at a particular time
蝠鲼会在特定的时间来到清洁站
but it has nothing to do with the time of day
但这与一天中的时间无关
like a runner on a treadmill the mantas require just the right amount of water movements
和在跑步机上跑步的人一样，蝠鲼需要适量的水流
so they can swim in place to be cleaned by the fish
所以它们会挑选一个合适的地方浮起，由鱼来清洗
they follow the timing of the Thais preferring to be clean just before or after slack tide when the water is moving but not too fast
蝠鲼遵循的是泰国人的时间，更喜欢在退潮前或退潮后保持清洁，因为此时海水在流动，但速度不会太快
this Manta is holding its mouth wide open so the cleaners can go inside
蝠鲼张大嘴巴，这样清洁鱼就可以进去了