未来星球：动物预警自然灾害

For millennia, people across the globe have reported alarmed animal behaviour in the run-up to natural disasters. Could these signals be used to warn us of impending catastrophes?

几千年来，世界各地都有传言在自然灾害发生前，动物会有惊恐的行为。我们能否利用这些信号来预警即将发生的灾难？
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In 2004, a tsunami triggered by a 9.1 magnitude undersea quake off Indonesia decimated coastal communities around the Indian Ocean, killing at least 225,000 people across a dozen countries. The huge death toll was in part caused by the fact that many communities received no warning.

2004年，印尼沿海发生9.1级海底地震，引发的海啸给印度洋周边的沿海社区造成了严重破坏，导致十多个国家至少22.5万人遇难，伤亡惨重的部分原因是许多社区没有收到预警。

Local manmade early warning systems, such as tidal and earthquake sensors, failed to raise any clear alx. Many sensors were out of action due to maintenance issues, while many coastal areas lacked any tsunami siren warning systems. Haphazard communication also failed to provide warnings, with many text messages failing to reach mobiles in threatened areas or going unread.

当地的人造预警系统并未发出明确的警报，例如潮汐和地震传感器。许多传感器由于维护不当而失灵，许多社区根本没有海啸预警系统。混乱的通信也没有提供预警，许多短信无法送达灾区的手机上，或者没被看到。
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Yet in the minutes and hours before surging walls of water up to 9m (30ft) high smashed through coastlines, some animals seemed to sense impending peril and make efforts to flee. According to eyewitness accounts, elephants ran for higher ground, flamingos abandoned low-lying nesting areas, and dogs refused to go outdoors. In the coastal village of Bang Koey in Thailand, locals reported a herd of buffalo by the beach suddenly pricking their ears, gazing out to sea, then stampeding to the top of a nearby hill a few minutes before the tsunami struck.

但是，在9米（30英尺）高的汹涌水墙冲破海岸线前几分钟和前几小时，有些动物好像觉察到了即将到来的危险，并且奋力逃脱。据目击者描述，大象往高地跑，火烈鸟逃离低洼栖息地，家狗不愿出门。在泰国沿海村庄Bang Koey，当地有传言在海啸来袭前几分钟，海边有一群水牛突然竖起耳朵，遥望大海，随后奔向附近的山头。

"Survivors also reported seeing animals, such as cows, goats, cats and birds, deliberately moving inland shortly after the earthquake and before the tsunami came," says Irina Rafliana, previously part of an advisory group for the United Nations International Strategy for Disaster Risk (UNISDR) and now a researcher at the German Development Institute in Bonn. "Many of those who survived ran along with these animals or immediately after."

“幸存者也曾说，在地震不久后和海啸来袭前，看到牛、羊、猫、鸟等动物有意向内陆迁移”，伊丽娜·拉弗利安娜说道。她曾是“联合国国际减灾战略”顾问小组的成员，现在是位于波恩的德国发展研究所的研究人员。“许多幸存者是与这些动物一起或紧随其后逃跑的”。

Rafliana recounts similar stories tied to her field work around other disasters, such as the 2010 tsunami generated by a subsea quake near Sumatra, which killed nearly 500 people on the Mentawai Islands. Here too, however, some animals, such as elephants, were reported to have responded as if possessing some kind of early knowledge of the event. Just days ago, a newly re-released turtle made a sudden U-turn two days before January's volcanic eruption in Tonga.

拉弗利安娜讲述了她在实地调查其他灾害中听到的类似情况，例如2010年，苏门答腊岛附近的海底地震引发了海啸，导致明打威群岛约500人遇难。但是，有传言说这里的大象等动物也有反应，好像预感到了灾难。在一月份汤加火山爆发前两天，一只海龟被放归时突然掉头返回。几天前，这只海龟被重新放归大海。

Early warning systems do not exist in many areas struck regularly by natural disasters. In 2017, the World Meterological Organisation found that the governments of around 100 countries still lack early warning systems for natural disasters to which they were prone.

许多自然灾害频发的地区没有预警系统。2017年，世界气象组织发现，约有100个国家政府对于多发的自然灾害仍然缺少预警系统。

But these accounts about animal behaviour before disasters have prompted some researchers to devote serious scientific attention to the theory that animals may have inbuilt systems which alx them to impending natural disasters. It raises an intriguing question – could animals provide natural early warning systems for humans?

但是，这些关于动物灾前行为的描述引起了科学家对一种理论的高度关注：动物可能天生就有预警自然灾害的系统。这引发一个有趣的问题——动物能否为人类提供天然的预警系统？

The earliest recorded reference to unusual animal behaviour prior to a natural disaster dates back to 373 BC, when the Greek historian Thucydides reported rats, dogs, snakes and weasels deserting the city of Helice in the days before a catastrophic earthquake. Other reports dot history. Minutes before the Naples quake of 1805, oxen, sheep, dogs and geese supposedly started making alarm calls in unison, while horses were said to have run off in panic just prior to the San Francisco earthquake of 1906.

关于灾前动物行为反常的最早记录可追溯到公元前373年，据当时的希腊历史学家修西得底斯记载：老鼠、狗、蛇、黄鼠狼在破坏性地震前几天逃离海利斯城。历史上也有其他记载：在1805年那不勒斯地震发生前几分钟，据说牛、羊、狗、鹅一同发出警叫声；在1906年洛杉矶地震发生前，据说马仓皇逃离。

Even with advanced technology it can be difficult to detect many kinds of impending natural disasters. In the case of earthquakes, for example, seismic sensors lurch into jolted squiggles only as the earth-juddering shocks are actually happening. Making reliable predictions requires precursor signals – and, as yet, scientists haven't found any signals that seem to occur consistently before big quakes. Hence the growing willingness of some scientists to consider more unorthodox warning signals – such as animal behaviour.

即使利用先进技术，也很难探测到即将发生的各种自然灾害。以地震为例，只有当地面确实出现振动时，地震传感器才会突现震动曲线。可靠的预测地震需要前兆信号——但在大地震发生前，科学家尚未发现任何连续的信号。因此，有些科学家逐渐愿意考虑不太正统的预警信号——比如动物行为。
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"Even with all the technology available today, we are not able to properly predict earthquakes or most natural catastrophes," says Charlotte Francesiaz, leader of an ornithological team at the French Biodiversity Office (OFB), and part of the Kivi Kuaka project, which is examining how migratory birds crossing the Pacific seem able to dodge storms and other hazards.

“就算用上当今所有的技术，我们依然无法准确预测地震或大多数自然灾害”，夏洛特·弗朗西塞兹说道。她是“法国生物多样性办事处”鸟类学团队负责人，也是Kivi Kuaka项目的参与者，该项目正在研究飞越太平洋的候鸟是如何避开风暴及其他灾害的。

One of the most important investigations into how animals could predict disasters was carried out five years ago by a team led by Martin Wikelski from the Max Planck Institute of Animal Behavior in Germany. The study involved recording the movement patterns of different animals (cows, sheep and dogs) – a process known as biologging – on a farm in the earthquake-prone region of the Marches in central Italy. Collars with chips were attached to each animal, which sent movement data to a central computer every few minutes between October 2016 and April 2017.

五年前，德国马克斯·普朗克动物行为研究所的马丁·维克尔斯基带领团队开展了一项最重要的调查，旨在研究动物是如何预测自然灾害的。这项研究记录了各种动物的活动模式（牛、羊、狗）——这种方法称为生物信标跟踪记录——地点位于意大利中部地震多发的马尔凯大区的一座农场。从2016年10月至2017年4月，每只动物被戴上装有芯片的项圈，每隔几分钟向中央计算机发送一次活动数据。

During this period, official statistics recorded over 18,000 quakes in the region, from tiny tremors measuring just 0.4 magnitude up to a dozen quakes notching 4 or above – including the devastating magnitude 6.6 magnitude Norcia earthquake.

在此期间，官方数据记录了该地区18000多次地震，其中既有0.4级的微震，也有10多次4级以上地震——包括破坏性的6.6级诺尔恰地震。

The researchers found evidence that the farm animals began to change their behaviour up to 20 hours before an earthquake. Whenever the monitored farm animals were collectively 50% more active for more than 45 minutes at a stretch, the researchers predicted an earthquake with a magnitude above 4.0. Seven out of eight strong earthquakes were correctly predicted in this way.

科学家发现的证据表明，在地震前20个小时，家畜的行为就开始发生变化。每当家畜被监测到总体活跃度增加50%并持续45分钟以上时，科学家就预测即将发生4.0级以上地震，他们以这种方式准确预测了8次强震中的7次。

"The closer the animals were to the epicentre of the impending shock, the earlier they changed their behaviour," Wikelski said in 2020 when the study was released. "This is exactly what you would expect when physical changes occur more frequently at the epicentre of the impending earthquake and become weaker with increasing distance."

“这些动物距离即将发生地震的震中越近，它们发生行为改变的时间越早”，维克尔斯基在2020年公布这项研究时说道。“这完全在意料之中，物理变化在即将发生地震的震中比较频繁，随着距离的增加而逐渐衰减”。

Another study carried out by Wikelski monitoring the movements of tagged goats on the volcanic slopes of Mount Etna in Sicily also found the animals seemed to have an advance sense of when Etna was going to burst into life.

维克尔斯基在另一项研究中监测了被标记山羊的活动，它们生活在西西里岛的埃特纳火山的斜坡上，结果发现当埃特纳火山即将喷发时，这些动物似乎有预感。

Over in South America, behavioural ecologist Rachel Grant – now at London South Bank University – has found similar results. She carried out biologging of animal movement patterns using motion-triggered cameras inside Yanachaga National Park in the Peruvian Andes over a period which included the magnitude 7.0 Contamana earthquake in 2011.

在南美洲地区，行为生态学家雷切尔·格朗——现就职于英国伦敦南岸大学——发现了类似结果。在秘鲁安第斯山脉的亚纳查加国家公园里，她利用活动感应式摄像机对动物的活动模式进行了生物信标跟踪记录，期间的2011年发生过7.0级康塔马纳地震。

"The number of animals recorded on the camera traps started to decrease about 23 days before the earthquake – with the decrease accelerating eight days prior to the earthquake," Grant said in her 2015 paper on the research. "On days 10, six, five, three and two prior to the earthquake – and on the day of the earthquake – no animal movements were recorded, which is highly unusual."

“大约在地震发生前23天，相机陷阱拍摄到的动物数量开始减少——在地震前的8天，数量减少速度加快”，格朗在2015年的研究报告中写道。“在地震前的10天、6天、5天、3天、2天——以及地震当天——摄像机没有拍摄到任何动物活动，这极不寻常”。

Crucially, Grant also found evidence of what might be triggering the changes in local animal behaviour, in the shape of a series of strong perturbations in local atmospheric electric charges every two to four minutes, starting two weeks before the earthquake. A particularly large fluctuation was recorded around eight days before the Contamana earthquake – coinciding with the start of the second stage of the animals disappearing from view.

关键是格朗还发现了证据，证明从地震前两周开始，大气层中的电荷每隔两到四分钟会出现一系列的强烈扰动，这可能是当地动物发生行为变化的原因。大约在康塔马纳地震前8天，电荷扰动尤为剧烈——这与动物从视野中消失的第二阶段的起始时间相吻合。

Scientists are now exploring whether these electromagnetic perturbations in the atmosphere prior to earthquakes could be a warning sign of impending quakes which animals may be sensing.

科学家正在探究在地震发生前，大气层中的电磁扰动能否成为地震的预警信号，这些信号可能被动物感知到。

Earthquakes are invariably preceded by a period when severe stresses arise in deep rock – stresses known to create electronic charges called "positive holes". These highly mobile electronic charge carriers can flow quickly from the crust to the Earth's surface, where they ionise air molecules above where they appear. Such ionisation has been noted prior to quakes across the globe. As these positive holes flow, they also generate ultra-low frequency electromagnetic waves, providing an additional signal that some animals may be able to pick up.

在地震发生前，深部岩石总是产生巨大应力——应力产生的电荷称为“正孔”。这些具有高流动性的电荷载体能从地壳迅速到达地表，使上方的空气分子发生电离，全球各地在地震前都已注意到这种电离现象。“正孔”在流动中还产生超低频的电磁波，某些动物也许能够感知到这些额外信号。
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"Earthquake precursors aren't well documented scientifically," says Matthew Blackett, associate professor in physical geography and natural hazards at Coventry University. But some scientists theorise that animals could have evolved a seismic escape mechanism, he says. "Perhaps they detect pressure waves before earthquakes arrive, perhaps they detect changes in electric field as fault lines when rock starts to compress. Animals also contain a lot of iron, which is sensitive to magnetism and electric fields."

“地震前兆在科学上证据不足”，英国考文垂大学自然地理学与自然灾害副教授马修·布莱克特说道。但有些科学家推测，动物可能进化出某种地震逃生机制，他说道。“也许它们在地震前感知到了压力波，也许在岩石开始压缩时，它们感知到了断层线的电场发生变化。另外，动物体内含有大量铁元素，对磁力和电场很灵敏。

Positive holes could also cause certain toxic chemicals to appear before quakes. For example, if they come into contact with water, they can trigger oxidation reactions which create the bleaching agent hydrogen peroxide. Chemical reactions between the charge carriers and organic matter in the soil could trigger other unpleasant products such as ozone.

在地震发生前，“正孔”还可能产生某些有毒化学物。例如，它们与水接触发生氧化反应，产生过氧化氢这种漂白剂。“正孔”点和载体与土壤有机物发生化学反应，会产生其他令人不适的产物，例如臭氧。

Meanwhile, days before the 7.7 magnitude Gujarat earthquake in India in 2001, a surge in carbon monoxide levels was picked up by satellites over a 100 square kilometre (39 sq mile) region centred on what turned out to be the epicentre of the eventual quake. Scientists have suggested that carbon monoxide gas could be forced out of the earth due to the build-up of stress in rocks as quake pressure builds.

另外，在2001年印度7.7级古吉拉特邦地震发生数天前，卫星探测到方圆100平方公里（39平方英尺）区域的一氧化碳浓度激增，后来证明该区域的中心就是这场地震的震中。科学家认为，岩石内的应力会随着地震压力的积聚而增强，可能迫使一氧化碳气体从地面释放出来。

Many animals, of course, are equipped with highly developed sensory apparatus that can read an array of natural signals on which their lives may depend – so it seems perfectly possible that some animals may be able to pick up any earthquake precursors. Unpleasant chemicals could be sniffed out, low frequency waves picked up, and ionised air sensed by sensations in fur or feathers.

许多动物显然具备高度发达的感觉器官，能读懂一系列它们可能赖以生存的大自然信号——看来某些动物完全有可能接收到地震前兆。它们可能嗅到不适的化学物质，接收到低频波，皮毛或羽毛感知到电离空气。

With earthquakes so difficult to anticipate, these findings beg the question: could humans actually predict earthquakes by animal observations, and thus be able to warn people they are coming?

由于预测地震的难度非常大，这些发现引出的问题是：人类能否通过观察动物来真正预测地震？从而向人们发出预警？

In a 2020 paper, Wikelski and his colleagues set out a prototype for an earthquake early warning system using animal activity monitoring sites, based on data from his research in Italy. He estimated that farm animals above the point of origin of the imminent earthquake which were able to perceive it in some way would show activity 18 hours before it hit. Animals situated 10km (6.2 miles) away from the epicentre should show warning signs eight hours later, followed by animals at farms 20km (12.4 miles) away a further eight hours later. "If correct, this would indicate an earthquake is imminent within the next two hours," he says.

2020年，维克尔斯基及其同事在论文中提出一种地震预警原型系统，该系统利用多个动物活动监测点，以他在意大利的研究数据为基础。如果家畜位于即将发生地震的震源点上方，并具备以某种方式预知地震的能力，他估算家畜在地震前18个小时就有活动迹象。如果家畜距离震中10公里（6.2英里），发出预警的时间会推迟8个小时，距离震中20公里（12.4英里）会进一步推迟8个小时。“如果没错的话，这预示着未来两小时内将发生地震”，他说道。

Researchers will need to observe a larger number of animals over longer periods of time in different earthquake zones around the world before they can be used to predict earthquakes. For this, Wikelski and others are turning to the global animal observation system Icarus on the International Space Station to gather movement data for animals globally.

科学家将需要在全世界的地震带对更多的动物进行更长期的观察，才能利用动物预测地震。维克尔斯基等人为此求助国际空间站上的全球动物监测系统Icarus，收集全球动物的活动数据。

Icarus (International Cooperation for Animal Research Using Space) is an initiative set up by a global collaboration of scientists in 2002. It aims to provide an accurate global observation system for an array of tagged small animals (such as birds) to provide data and clues about interactions between the planet's animal life and its physical systems.

Lcarus（太空辅助动物研究国际合作组织）是于2002年由全球科学家联合创办的项目，旨在为一系列的标记小动物（例如鸟）提供精确的全球监测系统，从而为了解地球上的动物生命与物理系统的相互影响提供相关数据和线索。

China, meanwhile, has already created a Quake alx system based at its earthquake bureau in Nanning, monitoring the behaviour of animals much closer to the ground – specifically, snakes in farms across a wide quake-prone region. Snakes possess a powerful array of sensory mechanisms geared to detecting tiny changes in aspects of their environment, and it was in part sudden changes in the behaviour of snakes and other animals which prompted authorities to evacuate the Chinese city of Haicheng in 1975, just before a major quake struck – an action that saved countless lives.

另外，中国在南宁地震局建立了地震预警系统，监测比较贴近地面的动物的行为——确切地说是在地震多发区里的农田蛇。蛇类具备一套强大的感官机制，用于感知周边环境的细微变化。1975年，在中国海城市大地震发生不久前，蛇类及其他动物的行为突然出现变化，在某种程度上促使政府疏散转移群众，这一行动拯救了无数条生命。

"Of all the creatures on the earth, snakes are perhaps the most sensitive to earthquakes," Jiang Weisong, then director of the Nanning bureau, told China Daily in 2006. "When an earthquake is about to occur, snakes will move out of their nests, even in the cold of winter."

“在所有的地球生物中，蛇类可能对地震最为敏感”，2006年时任南京地震局局长的Jiang Weisong在接受《中国日报》采访时说道。“当要发生地震时，蛇类将倾巢而出，寒冷的冬天也不例外”。

Earthquakes are not the only environmental dangers animals seem to have advanced warning of. Birds are increasingly in the spotlight for apparently being able to detect other approaching natural hazards.

动物似乎能够预警的环境威胁不只是地震，鸟类明显能够预知其他即将到来的自然灾害，因此越来越受关注。

In 2014, scientists tracking golden-winged warblers in the US recorded a startling example of what's known as an evacuation migration. The birds suddenly took off from their breeding ground in the Cumberland Mountains of eastern Tennessee and flew 700km (435 miles) away – despite having just flown 5,000km (3,100 miles) in from South America. Shortly after the birds left, a terrifying swarm of over 80 tornadoes struck the area, killing 35 people and causing over $1bn (£740m) in damage.

2014年，当科学家在美国追踪金翅莺的行踪时，记录到一种被称为逃离迁徙的惊人现象。这些金翅莺突然离开田纳西州东部坎伯兰山脉的繁殖地，飞到700公里（435英里）以外的地方——但它们不久前刚从南美洲飞行5000公里（3100英里）到达这里。这些金翅莺离开不久后，80多场可怕的龙卷风袭击了该地区，导致35人死亡，造成的经济损失超过10亿美元（7.4亿英镑）。

The suggestion seemed clear – the birds had somehow sensed the twisters coming from more than 400km (250 miles) away. As to how, initial focus is on infrasound – low frequency background sounds inaudible to humans, but present throughout the natural environment.

看来迹象很明确——这种鸟以某种方式感知到龙卷风正在从400公里（250英里）远处袭来。最初的焦点是次声波——人类听不见这种低频背景音，但它在自然界无处不在。

"Meteorologists and physicists have known for decades that tornadic storms make very strong infrasound that can travel thousands of kilometres from the storm," Henry Streby, a wildlife biologist at the University of California, Berkeley, said at the time. He further noted that infrasound from severe storms travels at a frequency the birds would have been well attuned to hearing.

“几十年前，气象学家和物理学家就已知道龙卷风暴发出非常强烈的次声波，传播距离达数千公里”，美国加州大学伯克利分校的野生动物生物学家亨利·斯特比当时说道。他还发现强烈风暴发出次声波的传播频率能够被鸟类听到。

Detecting variation in infrasound is also thought to be the mechanism by which migrating birds seem able to dodge storms on vast ocean crossings – an idea now being tested by the ongoing Kivi Kuaka study in the Pacific Ocean.

科学家认为，当候鸟飞越浩瀚的海洋时，似乎还能通过感知次声波的变化来躲避风暴——正在太平洋进行的Kivi Kuaka研究项目正在检验这一想法。

This study was inspired by a radio programme French navy officer Jérôme Chardon listened to about a bird called the bar-tailed godwit, which every year migrates 14,000km (8,700 miles) between New Zealand and Alaska. As an experienced coordinator of rescue operations across Southeast Asia and French Polynesia, Chardon knew how treacherous this journey would be. Fierce storms frequently lash the Pacific and its diaspora of isolated island communities. So how were bar-tailed godwits seemingly able to make their annual journeys without being hindered by these ever-present stormy hazards?

这项研究的灵感来自法国海军军官杰罗姆·查尔顿收听的一档广播节目，说的是一种被称为斑尾塍鹬的鸟类每年在新西兰和阿拉斯加之间迁徙14000公里（8700英里）。在东南亚和法属波利尼西亚，查尔顿是一名经验丰富的救援行动协调员，他知道这段迁徙旅程有多凶险。猛烈的风暴经常袭击太平洋及其孤岛移民社区，那么每年斑尾塍鹬是如何躲过这些经常存在的风暴灾害而完成迁徙的？
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Set up in January 2021, the project involves a team from France's National Museum of Natural History fitting 56 birds of five different species with GPS trackers to follow the routes they take across the ocean. The International Space Station provides oversight, receiving signals from the birds as they fly – and observing how they respond to natural hazards en route. Their tags also collect meteorological data to help improve climate modelling and weather forecasting across the Pacific.

2021年1月，法国国家自然历史博物馆的一支团队创立了该项目，他们将GPS跟踪器安装在56只五种不同的鸟身上，追踪它们飞越海洋的路线。国际空间站负责监测，接收鸟类飞行中发出的信号——并观察它们在飞行途中如何应对自然灾害。它们身上的跟踪器还收集气象数据，有助于提高太平洋的气候模拟和天气预报。
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Kivi Kuaka will also look at whether bird behaviour could warn against more infrequent hazards like tsunamis, which are known to generate distinctive infrasound patterns that race ahead of the actual waves. The project aims to test birds' possible contribution to an early warning system informing the imminent arrival of a typhoon or tsunami, says Francesiaz. The team is currently in the process of retrieving GPS tags on curlews to examine whether they reacted to an infrasound wave registered by French meteorological balloons in the Pacific a few hours after the recent volcano eruption in Tonga.

Kivi Kuaka项目还将观察鸟类行为能否预警不常发生的灾害，以海啸为例，在真正的波形出现之前会产生独特的次声波形。该项目旨在测试鸟类对台风或海啸预警系统可能做出的贡献，弗朗西塞兹说道。目前，该团队正在回收鹬身上的GPS跟踪器，检查它们对次声波是否有所反应，最近在汤加火山爆发几小时后，太平洋上的法国气象气球记录了这些次声波。

Samantha Patrick, a marine biologist at the University of Liverpool, is also examining infrasound as a method by which birds can detect and avoid natural hazards – and, by extension, perhaps alx humans too. "I think we can say it is possible that birds can sense changes in infrasound," she says. Patrick is currently looking at whether albatrosses show a preference for areas of high or low infrasound, although the analysis is not yet complete.

萨曼莎·帕特里克是来自利物浦大学的海洋生物学家，她也在调查鸟类利用次声波作为感知和躲避自然灾害的手段——更进一步而言，也许还能为人类提供预警。“我认为鸟类感知次声波的变化是可能的”，她说道。目前，帕特里克正在观察信天翁是否偏爱高频或低频的次声波，但相关分析尚未完成。

Not all experts think that animal early warning systems are a viable option for predicting disasters. And even if they do help, animal movements alone are unlikely to be enough to provide: people will need to rely on a combination of early warning signals to get the full picture.

并不是所有的专家都认为，动物的预警系统可被用来预测自然灾害。即使有帮助，仅仅依靠动物行为也不足以提供预警：人们需要依靠综合的预警信号才能了解全貌。

Still, while we may not be able to talk to animals quite yet, perhaps it's time to pay more attention to their warnings.

尽管我们还无法跟动物对话，但也许是时候对它们的预警多加注意了。