南非沙丁鱼大迁徙路线及原因

sardines by the billions live here year round swimming and feeding together in loose shoals of hundreds of thousands of individuals， then in late april ocean currents undergo a subtle shift as the southern winter approaches upwellings and eddies force a tendril of cold water toward the east the warm agullus current moves further offshore allowing the cold stream to gain momentum the cold water sardines instinctively cluster in the chillier current one hundred fifty miles out to sea on the agullus banks schools begin to mass together until they form a mega show twenty miles long then the single super organism pours into the cold water highway toward the coast and shallower water it's the biggest biomass migration on the planet exceeding the great herds of the serengetti yet exactly why they do it remains a mystery？ the journey serves no apparent benefit to the fish it will inevitably deadened in a warm sea unsuitable for sardines how far they travel depends entirely on the vagaries of this year's cold current， but one thing is certain an entire food web is counting on the sardines to make the run。

normally kingfish a solitary but for just a few weeks he cure they gather at places like bazaruto and prepare for an extraordinary journey one that will take them far in land the intent to river the king of kingfish leaves them upstream as they travel further into fresh water they seemed to change from aggressive hunters into dedicated pilgrims now many miles from their natural home and in response to an unknown cue they stop and begin to circle other marine fish that my great up river usually do so in order to breathe， but there's no evidence that these kingfish spawn up here neither do they hunt so what are they doing in truth？ the purpose of this strange behavior is still unknown within a few weeks they will retrace their journey back to the ocean the lives of kingfish like those of turtles and butterflies and pelicans are influenced by the agulus current， but that influence can only reach so far and this is why the drakensburg mountains here？ local people say that the vultures saw so high， they can see into the future these sheer cliffs rising to over three thousand meters hold back the advancing rain clouds and as a result the land beyond them is starved of water this is the greatest expansive sand in the world a seemingly endless desert that is the vast parched center of south africa thousands of miles to the west where this desert meets the atlantic ocean another current prevails but the banguela current surging up the west side of africa has a very different character， it's extremely cold full of nutrients and it's thronged with life a great white shark they can raise their body temperature to ten degrees above that of the surrounding sea but doing so requires an enormous amount of high grade fuel so this is a great banana for them the body of a dead whale， the carcass will draw in every great white for miles around and here off cape town that means a lot of sharks instead of feeding and friends these sharks have rather refined table manners they swim side by side to get the measure of each other then each takes its turn this female is the biggest so she eats first the next only feeds when she gives way the waters of the bangweller are so rich they support more great white sharks than any other seas on the planet and they are so cold they attract some surprising creatures to these african shores penguins， african penguins this female is returning to relieve her partner of course， there's no ice here but these rocks can be almost as slippery， but there are more serious circles then slippery rocks awaiting them it's his turn to feed so he leaves her to look after their eggs now she must tackle a problem faced by no other kind of penguin for the next ten days she must protect her eggs from the african sun。

每年，数以亿计的沙丁鱼从非洲南部附近的冷水域沿着东部海岸一路向北进入印度洋。今日，水下摄影师和爱好者见证呢，并拍下了沙丁鱼千玺的震撼画面。 北半球的夏季正值南半球的冬季。难以计数的沙丁鱼从非洲南部的寒冷水域奋力向北迁徙到亚热带水域。 这些鱼群阵容之庞大可以绵延几公里长。当沙丁鱼感受到威胁时，他们会集结在一起，旋转成一个巨大的银圈， 目的是利用这种防御机制来迷惑捕食者。在遭遇不同险情时，沙丁鱼群也会不断变换队形进行防御。 你咋了？还不来？通常在七月份，沙丁鱼的千玺规模会达到峰值。 对浮游生物的需求以及海洋中寒流的分布迫使沙丁鱼群更靠近海岸和海面，这使他们很容易成为各类捕食者的目标。 虽然千玺之路遭遇到天敌们的阻拦，沙丁鱼大军依旧一往无前，寻找适合他们的海洋新天地。

这是地球上最大的鱼巢，是世界海洋上最壮观的场面。六月份南半球的冬季，南非东海岸，数以亿计的沙丁鱼向北推进，肉食动物大军尾随而来。规模之大，冠军全球。 沙丁鱼喜欢冷水，所以在夏季，沙丁鱼隐匿在大海中，很难找到他们的踪迹。海豚是猎捕沙丁鱼的专家，煎鸟也以沙丁鱼为食。他们寻找鱼群的最好方式就是跟着海豚。 海豚使用本身的声纳系统定为猎物。海豚找到一小群鱼，他们将沙丁鱼赶到海面。尖鸟的机会来了，投机取巧的海豹也尾随而来。尖鸟面对艰难的抉择，冒险与敌人并肩下潜或者饿死。 如果不快点放手一搏，眼看食物就要被抢光了。幸好海豹有沙丁鱼可吃，根本不理会他们。大批捕食者都趁机赶来捡便宜。鱼群几秒钟就会消失。竞争非常激烈。但是对强大的猎手来说，事件绰绰有余。 捕食经巨口一张，吞掉一大团沙丁鱼。在沙丁鱼潮到来之前，这些还都只是小插曲。夏天，所有捕食者都食不果腹，他们都在等待六月份南半球冬季的到来。 三月份，夏末秋初的时候，向南的暖流逐渐减弱，向北的冷流增强，沿着海岸向北推进，冷流将裹挟着沙丁鱼，把它们推往岸边。大概再过三个月，沙丁鱼潮就会来临。

数千千米外，沿着非洲东海岸，另一场规模更大的迁徙即将到来。 冷水洋流冲击海岸，由此引发了最壮观的自然现象之一沙丁鱼风暴。 不计其数的银色沙丁鱼离开他们夏天的家，跟随杨柳顺着海岸游去。 所有沙丁鱼一条挨着一条，方向一致，好似一个整体。 在以沙丁鱼为食的动物看来，这简直就是移动的 盛宴。 从空中俯瞰，密密麻麻的沙丁鱼就像海面上的浮游， 空中的捕食者能轻易发现目标。而南非尖鸟是寻找沙丁鱼的专家。 鲨鱼像无声的潜艇一样从深海里游了上来。现在，沙丁鱼被夹在鲨鱼和水面之间。 海豚也前来赴宴。 他们是最有组织的捕食者。 海豚把沙丁鱼团分成无数个尔囚。 捕食者有条不稳的在耳囚周围游动，使沙令鱼紧紧的挤在一起，便于捕食。 沙丁鱼试图从下面逃跑，但海豚马上就注意到了，立即吹起泡泡。很快，沙丁鱼便再次围成一团。在四面八方 的夹击下，沙丁鱼没有一点逃生的机会。最后，尔求里成千上万条沙丁鱼，只剩下一些漂浮的鱼鳞。 盛宴结束了，依然还有成千上万条沙丁鱼游向海岸。 接下来的几个星期，鲨鱼、海豚以及南非尖鸟都可以尽情享用沙丁鱼美餐了。 沙丁鱼群长达五千多米，没有人知道这些沙丁鱼每年回游的真正原因是什么。 突然有一天，在袭击中幸存的沙丁鱼全都消失了。 他们游到海洋深处，远离海岸，跟随深海洋流回到了非洲南端的水域。

六七月份，在南非鄂加勒斯脚这块有一个浅滩，这沙丁鱼会从这出发，迁徙超过一千多公里。上千只的海豚，有时候你能看还有鲸鱼啊，成千上万的尖鸟在天 盘旋，各种就是鲨鱼，几十条上百条在围猎。这个鱼球非常震撼，不使劲从底下上来一口，把他们就这个 迟到一大半。为了延续他们种前赴后继，义无反顾的在前行路上，他会死掉不知道多少，但是他们就没有回头。这是自然界谱写的最伟大的，也是最悲壮的一个一个史诗吧。

我们在海上漂了十四天，终于拍到了上千万条沙丁鱼大千玺，结果不到一个小时就被团灭了。 上一次为了拍到沙丁鱼风暴，我去了菲律宾的墨宝，带着粉丝在零点零一秒的瞬间加入到一场风暴的狂欢中。这次为了拍到世界三大千玺奇观之一的沙丁鱼大千玺，我们团队来到了南， 整整十四天的焦急等待，我们每天派出飞机在海面上来回巡逻，在所有人都快失去耐心的那一刻，终于看到海豚跃出水面，他们来了 上亿位南非沙丁鱼北上千玺从高空俯瞰，如同一条巨型黑带，吸引了来自四面八方的捕猎者，猎杀一触即发，海豚家族冲锋陷阵大吃惊，带着宝宝迅速赶来，沙丁鱼团结成鱼尔琼，这是 小鱼群在受到威胁时会采取的防御措施。空中的南非坚鸟像一颗颗迅猛的炮弹，一头扎进水中，短尾针杀寻着血腥为而来。捕猎者们合作冲散这块大蛋糕，轮流分一杯羹， 最后出现的不吃惊，瞬间终结了这场混战。 why is freaking？ amazing？ 不到一个小时，上千万的沙丁鱼直接团灭。为了生命的延续，沙丁鱼不计大规模伤亡的代价，每年都义无反顾北上征战，脆弱又英勇。我们唯一能做的就是保护和记录这片蓬勃好汉的海洋，让这样的奇观永远流传下去。

在沙丁鱼大迁徙中，各种捕食者蜂拥而至，围追堵截，疯狂掠食沙丁鱼群损失惨重，却义无反顾， 在孕育新生的旅途中，绘制强有力的生命画卷。