鸭鸭虽然暂时不能去灭蝗了，但这些生物的确是生物防治的功臣

近来，巴基斯坦饱受蝗灾困扰。

前几日，社交媒体上突然出现了宁波晚报的消息称，中国将派出10万只鸭子赴巴基斯坦协助灭蝗。网友纷纷表示“一定要凯旋啊”。

但是，据澎湃新闻报道，此前盛传的“浙江10万只鸭子出征巴基斯坦灭蝗”表述不当。

 跟进报道的媒体还有《卫报》和BBC等。

BBC在报道中这样写道：

Lu Lizhi, a senior researcher with the Zhejiang Academy of Agricultural Sciences, told Bloomberg that the ducks are "biological weapons". He said that while chickens could eat about 70 locusts in one day a duck could devour more than three times that number. "Ducks like to stay in a group so they are easier to manage than chickens," he told Chinese media.

浙江省农业科学院高级研究员卢立志告诉彭博社：“鸭子是‘生物武器’，虽然鸡一天可以吃掉大约70只蝗虫，但一只鸭子可以吃掉超过这个数字三倍的蝗虫。鸭子喜欢成群结队，所以比鸡更容易管理。”

A trial involving the ducks will take place in China's western Xinjiang in the coming months, Mr Lu said. After that they will be sent to Pakistan's worst-affected areas of Sindh, Balochistan and Punjab provinces.

卢先生表示，在未来的几个月里，研究员将在中国西部的新疆对这些鸭子进行试验。之后，鸭子们将被派往巴基斯坦受灾最严重的信德省、俾路支省和旁遮普省帮助灭蝗。

 However, a professor from the China Agriculture University, who is part of the delegation to Pakistan, questioned whether the ducks would be suited to the mainly arid conditions where the locusts are a problem.

然而，中国农业大学的一位教授（他是中国赴巴基斯坦救灾代表团的一员）提出了质疑：这些鸭子是否适合在严苛的干旱环境下进行灭蝗工作。

"Ducks rely on water, but in Pakistan's desert areas, the temperature is very high," Zhang Long told reporters in Pakistan.

身处巴基斯坦的张龙教授告诉记者：“鸭子依赖水，但在巴基斯坦的沙漠地区，温度非常高。”

生物防治（biological control），指的就是利用一种生物对付另外一种生物（通常是害虫）的防止办法，一般分为三种：猎食者（predator）、病原体（pathogen）、和寄生虫（parasite）。

 猎食者Predator

这次新闻中提到的鸭子就是生物防治中猎食者的一种。

Predators kill and feed on several to many individual prey during their lifetimes. Many species of amphibians, birds, mammals, and reptiles prey extensively on insects. Predatory beetles, flies, lacewings, true bugs (Order Hemiptera), and wasps feed on various pest insects or mites.

捕食者在其一生中会捕杀和猎食数个到多个个体猎物。许多两栖动物、鸟类、哺乳动物和爬行动物都广泛捕食昆虫。掠食性甲虫、苍蝇、剑翅、真昆虫（半翅目）和黄蜂也以各种害虫或螨虫为食。

 病原体Pathogen

据Science报道，这次的蝗灾蔓延到非洲国家索马里之后，当地会用到真菌来防治蝗虫。在生物防治的办法中，真菌属于病原体防治的一种。

Somalia, one of several African nations being hit hard by enormous swarms of locusts, is planning to control them with a fungus in what would be the largest use of biopesticides against these insects.

索马里是几个遭受蝗虫袭击的非洲国家之一，该国正计划用一种真菌来控制蝗虫，这将是杀灭害虫的生物杀虫剂规模最大的一次使用。

“Large-scale use to control an invasion of desert locusts would be a first,” says Michel Lecoq, a retired entomologist who worked on locust control at the French Agricultural Research Center for International Development. “If successful, it will be a big step forward.”

法国国际发展农业研究中心从事蝗虫防治工作的退休昆虫学家米歇尔·莱科克表示：“这是第一次大规模使用生物杀虫剂来控制沙漠蝗虫入侵。如果成功了，那么这将是向前迈出的一大进步。”

Young locusts, such as these (pictured) in northern Somalia, will be killed by a nontoxic biocontrol fungus before they swarm. (The biopesticides) consist of spores of the fungus Metarhizium acridum, which produces a toxin that kills only locusts and related grasshoppers.

索马里北部的幼蝗（如上图所示）在成群聚集之前就会被一种无毒的生物防治真菌杀死。（该生物杀虫剂）由真菌（Metrahizium acridum）的孢子组成，该真菌产生的毒素只会杀死蝗虫和相关的蝗虫。

 寄生虫Parasite

在猎食者与病原体防治两种生物防治方法之外，寄生虫法也是重要的一环。寄生虫通常会寄居在宿主的体内或表面，依靠宿主的营养来养活自身。

A parasite is an organism that lives and feeds in or on a host. Insect parasites can develop on the inside or outside of the host’s body. Often only the immature stage of the parasite feeds on the host.

寄生虫是一种生活在宿主体表或体内，并以宿主为食的有机体。昆虫寄生虫可以在宿主体内或体外发育，通常只在未成熟阶段以宿主为食。

Most parasitic insects are either flies (Order Diptera) or wasps (Order Hymenoptera). Parasitic wasps occur in over three dozen Hymenoptera families. For example, Aphidiinae (a subfamily of Braconidae) attack aphids.

大多数寄生昆虫不是苍蝇（双翅目）就是黄蜂（膜翅目）。寄生蜂有三十多个膜翅目科，例如蚜虫亚科（茧蜂科的一个亚科）的昆虫就会攻击蚜虫。

Trichogrammatidae parasitize insect eggs. Aphelinidae, Encyrtidae, Eulophidae, and Ichneumonidae are other groups that parasitize insect pests. It’s important to note that these tiny to medium-sized wasps are incapable of stinging people.

赤眼蜂会寄生在昆虫卵里。隐蝇科、跳小蜂科、巨蝇科和姬蜂科的昆虫们也会寄生在害虫体内。值得注意的是，这些小到中等大小的黄蜂是不会蜇人的。