How Madagascar`s bats are helping to save the rainforest 

马达加斯加的蝙蝠如何帮助拯救热带雨林

There are few places in the world where relations between agriculture and conservation are more strained. Madagascar`s forests are being converted to agricultural land at a rate of one percent every year. Much of this destruction is fuelled by the cultivation of the country`s main staple crop: rice. And a key reason for this destruction is that insect pests are destroying vast quantities of what is grown by local subsistence farmers, leading them to clear forest to create new paddy fields. The result is devastating habitat and biodiversity loss on the island, but not all species are suffering. In fact, some of the island`s insectivorous bats are currently thriving and this has important implications for farmers and conservationists alike. 

世界上没有几个地方的农业和自然保护之间的关系比这里更紧张。马达加斯加的森林正以每年百分之一的速度转化为农业用地。造成这种破坏的主要原因是该国的主要粮食作物--水稻的种植。造成这种破坏的一个重要原因是，虫害破坏了当地自给农户种植的大量水稻，导致他们不得不砍伐森林来开辟新的稻田。其结果是岛上栖息地和生物多样性遭到毁灭性破坏，但并非所有物种都深受其害。事实上，岛上的一些食虫蝙蝠目前正在茁壮成长，这对农民和保护主义者都具有重要意义。

Enter University of Cambridge zoologist Ricardo Rocha. He`s passionate about conservation, and bats. More specifically, he`s interested in how bats are responding to human activity and deforestation in particular. Rocha`s new study shows that several species of bats are giving Madagascar`s rice farmers a vital pest control service by feasting on plagues of insects. And this, he believes, can ease the financial pressure on farmers to turn forest into fields. 

剑桥大学动物学家里卡多-罗卡（Ricardo Rocha）。他对自然保护和蝙蝠充满热情。更具体地说，他对蝙蝠如何应对人类活动，尤其是森林砍伐的问题很感兴趣。罗卡的新研究表明，马达加斯加的水稻种植者可以通过捕食昆虫来控制害虫。他认为，这可以减轻农民将森林变成田地的经济压力。

Bats comprise roughly one-fifth of all mammal species in Madagascar and thirty-six recorded bat species are native to the island, making it one of the most important regions for conservation of this animal group anywhere in the world. 

蝙蝠约占马达加斯加所有哺乳动物物种的五分之一，有 36 种有记录的蝙蝠是马达加斯加岛的原生物种，因此马达加斯加岛是世界上保护这一动物群体最重要的地区之一。

Co-leading an international team of scientists, Rocha found that several species of indigenous bats are taking advantage of habitat modification to hunt insects swarming above the country`s rice fields. They include the Malagasy mouse-eared bat, Major`s long-fingered bat, the Malagasy white-bellied free-tailed bat and Peters` wrinkle-lipped bat. 

罗卡共同领导了一个国际科学家小组，他发现有几种本土蝙蝠正利用栖息地的改变来捕食在该国稻田上空蜂拥而至的昆虫。这些蝙蝠包括马达加斯加鼠耳蝠、马约尔长指蝠、马达加斯加白腹自由尾蝠和彼得斯皱唇蝠。

These winner species are providing a valuable free service to Madagascar as biological pest suppressors,` says Rocha. `We found that six species of bat are preying on rice pests, including the paddy swarming caterpillar and grass webworm. The damage which these insects cause puts the island`s farmers under huge financial pressure and that encourages deforestation.

罗卡说："这些获胜物种作为害虫生物抑制剂，为马达加斯加提供了宝贵的免费服务。我们发现，有六种蝙蝠正在捕食水稻害虫，包括稻飞虱和禾网虫。这些昆虫造成的破坏给岛上的农民带来了巨大的经济压力，并助长了森林砍伐。

The study, now published in the journal Agriculture, Ecosystems and Environment, set out to investigate the feeding activity of insectivorous bats in the farmland bordering the Ranomafana National Park in the southeast of the country. 

这项研究发表在《农业、生态系统与环境》（Agriculture, Ecosystems and Environment）杂志上，旨在调查该国东南部与拉诺玛法纳国家公园（Ranomafana National Park）毗邻的农田中食虫蝙蝠的觅食活动。

Rocha and his team used state-of-the-art ultrasonic recorders to record over a thousand bat `feeding buzzes` (echolocation sequences used by bats to target their prey) at 54 sites, in order to identify the favourite feeding spots of the bats. They next used DNA barcoding techniques to analyse droppings collected from bats at the different sites. 

罗卡和他的团队使用最先进的超声波记录仪在 54 个地点记录了一千多个蝙蝠 “进食嗡嗡声”（蝙蝠瞄准猎物时使用的回声定位序列），以确定蝙蝠最喜欢的进食地点。接下来，他们使用DNA条形码技术分析在不同地点收集到的蝙蝠粪便。

The recordings revealed that bat activity over rice fields was much higher than it was in continuous forest – seven times higher over rice fields which were on flat ground, and sixteen times higher over fields on the sides of hills – leaving no doubt that the animals are preferentially foraging in these man-made ecosystems. The researchers suggest that the bats favour these fields because lack of water and nutrient run-off make these crops more susceptible to insect pest infestations. DNA analysis showed that all six species of bat had fed on economically important insect pests. While the findings indicated that rice farming benefits most from the bats, the scientists also found indications that the bats were consuming pests of other crops, including the black twig borer (which infests coffee plants), the sugarcane cicada, the macadamia nut-borer, and the sober tabby (a pest of citrus fruits). 

录音显示，稻田中的蝙蝠活动量比连片森林中的蝙蝠活动量高得多--平地稻田中的蝙蝠活动量是平地稻田中的七倍，而山丘两侧稻田中的蝙蝠活动量是山丘两侧稻田中的十六倍--毫无疑问，这些动物更喜欢在这些人造生态系统中觅食。研究人员认为，蝙蝠之所以喜欢这些田地，是因为缺水和养分流失使这些作物更容易遭受虫害。DNA 分析显示，所有六种蝙蝠都以具有重要经济价值的害虫为食。虽然研究结果表明水稻种植从蝙蝠身上获益最多，但科学家们也发现，有迹象表明蝙蝠也在捕食其他农作物的害虫，包括黑枝螟（为害咖啡植株）、甘蔗蝉、澳洲坚果螟和清醒蝠（柑橘类水果的一种害虫）。

The effectiveness of bats as pest controllers has already been proven in the USA and Catalonia,` said co-author James Kemp, from the University of Lisbon. `But our study is the first to show this happening in Madagascar, where the stakes for both farmers and conservationists are so high.

蝙蝠作为害虫控制者的有效性已在美国和加泰罗尼亚得到证实，"共同作者、里斯本大学的詹姆斯-坎普（James Kemp）说。但我们的研究首次证明了蝙蝠在马达加斯加的作用，因为在马达加斯加，农民和保护主义者都面临着巨大的风险。

Local people may have a further reason to be grateful to their bats. While the animal is often associated with spreading disease, Rocha and his team found evidence that Malagasy bats feed not just on crop pests but also on mosquitoes – carriers of malaria, Rift Valley fever virus and elephantiasis – as well as blackflies, which spread river blindness. 

当地人或许还有理由感谢他们的蝙蝠。蝙蝠通常与传播疾病联系在一起，但罗查和他的团队发现，有证据表明马达加斯加蝙蝠不仅捕食农作物害虫，还捕食蚊子--疟疾、裂谷热病毒和象皮病的携带者--以及传播河盲症的黑蝇。

Rocha points out that the relationship is complicated. When food is scarce, bats become a crucial source of protein for local people. Even the children will hunt them. And as well as roosting in trees, the bats sometimes roost in buildings, but are not welcomed there because they make them unclean. At the same time, however, they are associated with sacred caves and the ancestors, so they can be viewed as beings between worlds, which makes them very significant in the culture of the people. And one potential problem is that while these bats are benefiting from farming, at the same time deforestation is reducing the places where they can roost, which could have long-term effects on their numbers. Rocha says, `With the right help, we hope that farmers can promote this mutually beneficial relationship by installing bat houses.`

罗卡指出，这种关系很复杂。当食物匮乏时，蝙蝠成为当地人重要的蛋白质来源。甚至孩子们也会捕食它们。除了在树上栖息，蝙蝠有时也会在建筑物中栖息，但由于蝙蝠会使建筑物变得不干净，因此不受欢迎。但与此同时，它们又与神圣的洞穴和祖先联系在一起，因此它们可以被看作是世界之间的生命，这使得它们在当地人的文化中具有非常重要的意义。一个潜在的问题是，在这些蝙蝠从农耕中受益的同时，森林砍伐却减少了它们栖息的地方，这可能会对它们的数量产生长期影响。罗卡说："我们希望，如果有适当的帮助，农民可以通过安装蝙蝠屋来促进这种互利关系。

Rocha and his colleagues believe that maximising bat populations can help to boost crop yields and promote sustainable livelihoods. The team is now calling for further research to quantify this contribution. `I`m very optimistic,` says Rocha. `If we give nature a hand, we can speed up the process of regeneration.` 

罗卡和他的同事认为，最大限度地增加蝙蝠数量有助于提高作物产量和促进可持续生计。研究小组现在呼吁开展进一步研究，以量化这种贡献。罗卡说："我非常乐观。如果我们向大自然伸出援手，就能加快再生的进程。