杏吧原创

KEN RAMIREZ is an animal trainer with decades of experience, including a 25-year stint at the Shedd Aquarium in Chicago, Illinois. He has taught all sorts of creatures to do all manner of tricks. Once, he trained thousands of butterflies to perform a choreographed display in a botanical garden. It took several weeks, but even he was impressed with the result. 鈥淚 watched in awe,鈥� he says. 鈥淭hey appeared to undulate to the rhythm of the music 鈥� it was incredible!鈥�

These days, however, Ramirez is less likely to use his talents for entertainment. Instead, he is working to protect wild animals by tweaking their behaviour. That may sound intrusive, but, in a rapidly changing world where human activities can have fatal consequences for wildlife, evolution often can鈥檛 act fast enough to meet the challenges. So a growing number of conservationists aim to encourage wild animals to adapt by understanding and manipulating behaviours like hunting, foraging, mating and migration.

In fact, the approach resembles strategies increasingly adopted by governments and organisations to spur humans towards healthy or socially beneficial choices. Sometimes referred to as 鈥渘耻诲驳别蝉鈥�, these are based on the idea that, for example, we choose to eat more vegetables if we encounter a salad in the buffet line before pizza. Or that scarce parking in a city encourages us to cycle or take the bus. 鈥淎ll creatures learn the same way,鈥� says Ramirez. 鈥淟et鈥檚 make what we don鈥檛 want animals to do difficult and what we want them to do easy. A little nudge can guide them to do the things that are going to save them.鈥�

To train those butterflies, Ramirez taught them to associate a stimulus, such as a flash of light or a subsonic vibration, with a food reward. In this way, he got groups of the insects to fly in different directions on cue. He uses the same associative learning in the wild. One of his first forays into conservation was in Sierra Leone, where he helped local rangers protect a group of chimps from poachers. Sentinel chimpanzees would scream when poachers approached, but the rangers couldn鈥檛 hear them because their station was too far away. If only the whole troop shouted in unison, one ranger mused. Then the racket would alert the wardens. This gave Ramirez an idea 鈥� he set up pipes from which fruit and insects would fall into the trees where the apes sat. 鈥淲hen a person approached and they screamed, we would push a remote-control button that released the food,鈥� he says. 鈥淭hey quickly learned: 鈥業 scream, I get food鈥�. 鈥� Soon, all the chimps shrieked at any sight of a human. 鈥淧oaching was reduced by 86 per cent.鈥�

Attract or repel

Ramirez isn鈥檛 an academic; he operates in the field and doesn鈥檛 publish his work in scientific journals. But the idea that animal behaviour might hold the key to many conservation issues is catching on among academics too. It can , according to ecologist at Ben-Gurion University of the Negev in Israel. Frequently, it involves attempts to either attract or repel animals. Wildlife corridors are a good example 鈥� these green passageways have become a popular means to connect fragmented habitats, but there is a big problem. 鈥淥ften, you build them and the animals don鈥檛 use them,鈥� says Berger-Tal. Encouraging them to make that decision could be as simple as putting animal dung or urine on a new route to trick them into thinking that others have been there before.

In Banff National Park, Canada, biologists are using another nudge technique to . 鈥淲e speculated that there are circumstances where they don鈥檛 detect an approaching train early enough,鈥� says Colleen St Clair at the University of Alberta, Canada. So she and her colleague Jonathan Backs, also at the University of Alberta, used a system of train-triggered flashing lights and alarm bells to warn them. This not only prompted the grizzlies to move off the tracks sooner, but also a range of other animals including elks, wolves and even small mammals and birds. Similar approaches . Globally, vehicle collisions account for up to 10 per cent of known mortalities among mammals, including endangered species such as the Florida panther. Indeed, St Clair says the system has attracted interest in India, where trains and elephants often collide.

Conflict resolution

Human-wildlife conflicts are a particularly ripe area for behavioural conservationists. As the human population grows, people and wildlife clash more often, from elk invading towns to wolves killing livestock and geese defecating on golf greens. 鈥淚t used to be that whenever there was a problem, the animals would be culled,鈥� says at San Diego Zoo in California. But that 鈥渟olution鈥� never lasts because other animals just replace them. Increasingly, wildlife managers are trying to change the problematic behaviour itself. Take cranes, which are notorious for raiding farmers鈥� fields: a single bird can eat 400 kernels of corn daily, and a whole flock will easily decimate a freshly planted field. , but on areas set aside for the birds are even better.

鈥淭he approach resembles one increasingly used by governments to spur citizens to act in socially beneficial ways鈥�

Ramirez is using a similar carrot-and-stick approach in Zambia to deter elephants from crossing into the Democratic Republic of the Congo on their annual migration. 鈥淪adly, that country offers little protection against poachers and dozens of elephants get slaughtered every year,鈥� he says. With a team of helpers, he has been guiding the elephants on a detour around the danger zone. They used big trees to block the original path and created artificial waterholes to lure the animals on a new trail. 鈥淸Everything] is done remotely. The animals can never see you, never know that you had anything to do with what鈥檚 happening,鈥� says Ramirez. He sees signs that the project, now in its third year, is working. 鈥淭he elephants already seem to understand what they鈥檙e supposed to do.鈥�

People tend to underestimate animals, says St Clair. 鈥淭hat鈥檚 part of what makes me excited about this tool. We think we鈥檙e king of the heap of being able to learn, but all primates and carnivores are good at associative learning. Even really simple animals are capable of it.鈥�

鈥淓volution often can鈥檛 act fast enough for animals to meet the challenges posed by human activities鈥�

Some animals even seem to sense what is going on. St Clair recalls an incident involving an attempt to at the resort town of Whistler in British Columbia, Canada. Each year, millions of tourists descend on the area and rangers regularly have to shoot bears because they become dangerous to people while rifling through their trash. One of St Clair鈥檚 students was firing rubber bullets or marbles from a slingshot to hit bears that ventured close to human areas. Before doing so, however, she blew a warning whistle. If the bear ran away, she rang a bell to signal that the risk of getting hit was over. 鈥淥nce, she accidentally rang the bell too soon when the bear was only partway up the slope,鈥� says St Clair. 鈥淚t turned and looked at her as if to say, 鈥榓lready?'鈥�

Despite such seeming insight, attempts to adapt the behaviour of wild animals . In Australia, an endangered marsupial called the northern quoll successfully learned to avoid eating invasive cane toads, which are toxic, after biologists fed toad sausages laced with a nausea-inducing chemical to captive-raised quolls before releasing them. Yet spiking livestock carcasses with similarly unpleasant substances to try to persuade coyotes that farm animals aren鈥檛 worth eating hasn鈥檛 always deterred them from preying on sheep and cows.

A training approach might even work with one animal, but not another of the same species, says St Clair. 鈥�.鈥� than others.

But should we try to tinker in this way at all? Might we end up making wild animals more dependent on us? The question goes to the heart of conservation, says Berger-Tal. 鈥淥ne of the main goals of conservation is to keep evolution going. If we鈥檙e changing the way animals behave, it can change the evolutionary trajectory. It鈥檚 a trade-off.鈥�

Is this wise?

Yet, in some ways, this approach is less radical than it might seem. Training has long been an invaluable tool in preparing endangered animals reared in captivity to live in the wild. People might assume that they instinctively know how to behave, but many such animals are inept at evading predators or foraging and won鈥檛 survive unless they are taught these behaviours. For example, before Greggor releases rare Hawaiian crows called Alal膩; that she helps breed, she must teach them to open the seed pods that will provide them with food. 鈥淔irst, we give them pods that are already open. Then, we leave them a bit closed, then fully closed,鈥� she says. Likewise, when conservationists move wild animals from one area to another, they may need to teach them .

Besides, we already influence wildlife in multiple ways through our sheer presence. to drown out traffic. Urban . But purposefully shaping the behaviour of wild animals is a different matter. 鈥淚t鈥檚 important to really think it through,鈥� says behaviourist Liv Van de Graaff at Hunter College, New York. 鈥淗umans have a way of forgetting about impact if their intentions are good.鈥� She describes Ramirez鈥檚 idea of teaching chimps to scream to protect them from poachers as 鈥済reat鈥�. 鈥淚t鈥檚 non-invasive and taps into what these animals do anyway,鈥� she says. But she points out that it could also have unintended consequences. For example, it might raise their stress levels to engage in so much alarm calling. And then there is the question of how it changes the troop鈥檚 social dynamic if all chimps do the work of sentinels.

When it comes to side effects, we should consider worst-case scenarios, according to behavioural ecologist Lysanne Snijders at Wageningen University in the Netherlands. 鈥淔or example, we want to be sure when teaching an animal not to eat a particular food that it doesn鈥檛 generalise this to its natural food,鈥� she says. 鈥淚t wouldn鈥檛 be the first time that people try to solve one problem and create a bigger one.鈥�

鈥淎nimals have personalities too. Some of them are more inclined to accept nudges than others鈥�

Nudging in isolation may not be the best policy either. Even its staunchest advocates accept that nudging works best in combination with other tactics. For example, an essential way to keep bears out of towns is for people to lock up their rubbish and secure fruit trees and compost bins. 鈥淭here usually isn鈥檛 a single silver bullet,鈥� says St Clair.

Ramirez agrees that we should be cautious about possible ripple effects from changing the behaviour of animals. But he points out that conservationists may have few alternatives to nudges. The rangers in Sierra Leone, for example, couldn鈥檛 find another way to curb poaching. 鈥淚t comes down to: are the changes worth it?鈥� he says. 鈥淚 feel that we humans owe it to the animals to try to find solutions to the problems that, often, we have created.鈥�