为什么成群的蝗虫在东非肆虐?

为什么成群的蝗虫在东非肆虐?

The Horn of Africa, one of the world's most impoverished regions, is being ransacked by billions of tiny invaders.

非洲之角，世界上最贫穷的地区之一，正遭到数十亿小型入侵者的洗劫。

Farmers look on in horror as desert locusts moving in vast cloud-like swarms darken the sky. The insects blast through fields of crops at an astonishing pace, decimating livelihoods in the process.

农民们惊恐地看着沙漠蝗虫成群结队地移动，像云一样笼罩着天空。这些昆虫以惊人的速度席卷了庄稼田，在此过程中摧毁了人们的生计。

The pests crossed the Gulf of Aden and arrived in Somalia and Ethiopia last year. They were spotted in Kenya about two months ago in what has become the worst infestation there in 70 years. The U.N. says the region is already vulnerable to food shortages, and it warns that the international community only has a small window to prevent "looming catastrophe."

这些害虫去年越过亚丁湾，抵达索马里和埃塞俄比亚。大约两个月前，他们在肯尼亚被发现，这已经成为那里70年来最严重的虫害。联合国说，该地区已经容易受到粮食短缺的影响，并警告说，国际社会只有一个小窗口来防止“迫在眉睫的灾难”。

"These things are voracious," says Keith Cressman, the U.N. Food and Agriculture Organization's senior locust forecasting officer. A swarm the size of Manhattan can, in a single day, eat the same amount of food as everyone in New York and California combined, he says.

联合国粮农组织高级蝗虫预测官员基思·克雷斯曼说：“这些东西非常贪婪。”他说，一个曼哈顿大小的蜂群在一天内可以吃掉相当于纽约和加利福尼亚州每个人加起来的食物量。

Swarms of desert locusts more than three times the size of New York City — an estimated 192 billion insects — have been spotted in northeast Kenya, according to Save The Children.

根据拯救儿童组织的数据，在肯尼亚东北部发现了成群的沙漠蝗虫，面积是纽约市的三倍多-估计有1920亿只昆虫。

Experts know how to stop the locusts' spread, but say efforts have been stymied by a lack of resources and because its difficult to spray in conflict-racked places such as Somalia and Yemen.

专家们知道如何阻止蝗虫的蔓延，但他们表示，由于缺乏资源，而且很难在索马里和也门等冲突频发的地方喷洒杀虫剂，这一努力受到了阻碍。

"We do have a chance to nip this problem in the bud, but that's not what we're doing at the moment," Mark Lowcock, the U.N.'s top humanitarian official, said earlier this month. "We're running out of time."

“我们确实有机会将这个问题扼杀在萌芽状态，但这不是我们目前正在做的事情，”联合国的马克·洛考克说联合国负责人道主义事务的最高官员本月早些时候说。“我们没时间了。”

How it started and why it got so bad

它是如何开始的，为什么会变得如此糟糕

Desert locusts, or Schistocerca gregaria, are known for their rapid reproduction and ability to migrate long distances with the wind. In "quiet periods" they typically stay within deserts in Africa, the Near East and Asia, according to the Food and Agriculture Organization.

沙漠蝗虫以其快速繁殖和随风长距离迁徙的能力而闻名。据联合国粮农组织称，在“平静期”，它们通常停留在非洲、近东和亚洲的沙漠里。

"It's a pest that has been around for eons and eons of time," Cressman says. "It has so many different survival mechanisms ... to just survive in some of the harshest areas and most remote parts of this planet. But it has this fabulous capacity to take advantage of good conditions."

“这是一种存在了上亿万年的害虫，”克雷斯曼说。“它有很多不同的生存机制……在地球上最恶劣的地区和最偏远的地方生存但它拥有利用良好条件的惊人能力。”

In mid-2018. a group of these pests found themselves in excellent conditions when a cyclone from the Indian Ocean hit an extremely remote area of the Arabian Peninsula known as the "Empty Quarter."

2018年年中，当一股来自印度洋的龙卷风袭击了阿拉伯半岛一片极其偏远的地区(被称为“空荡区”)时，一群这样的害虫发现自己处于极好的状态。

"That was just a huge sandy area that got wet by these extraordinary rains. And this is exactly what desert locusts need in order to lay their eggs and to breed," Cressman says.

克雷斯曼说：“那只是一个巨大的沙区，被这些非同寻常的降雨弄湿了。这正是沙漠蝗虫产卵和繁殖所需要的。”

The animals reproduce rapidly – every three months. And they reproduce exponentially, he says, so in favorable conditions like these, the population could multiply by 400 times every six months.

这些动物繁殖迅速，每三个月一次。它们以指数方式繁殖，他说，所以在这样的有利条件下，种群每六个月可以繁殖400倍。

What's being done to stop the infestations

我们正在做什么来阻止虫害

The "only effective response," he says, is aerially spraying pesticide directly on the locusts to kill them. Countries such as Kenya and Ethiopia are actively spraying.

他说，“唯一有效的反应”是直接向蝗虫喷洒杀虫剂来杀死它们。肯尼亚和埃塞俄比亚等国正在积极喷洒。

"It's really important that these control operations are undertaken, but also that they're upscaled — because it's not enough," Cressman says. "The strategy is just to reduce these huge numbers and try to break this continuation of the breeding."

克雷斯曼说:“这些控制措施的实施非常重要，但同时也要扩大(控制)规模，因为当前是不够的。”“我们的策略就是减少这些庞大的数量，试图阻止这种继续繁殖。”

Security issues complicate efforts to stave off the infestations, particularly in parts of Somalia. "You can't work in places that aren't safe. You don't want to endanger people's lives," he says.

安全问题使防止虫害的努力复杂化，特别是在索马里部分地区。“你不能在不安全的地方工作。你不想危及人们的生命，”他说。

If control efforts fail, swarms of desert locusts are likely to re-invade Ethiopia and Somalia. And the timing of yet another generation of locusts could coincide with the harvest in Kenya.

如果控制努力失败，成群的沙漠蝗虫可能会再次入侵埃塞俄比亚和索马里。而新一代蝗虫的出现时间可能正好与肯尼亚的收获季节相吻合。