Nudges that help animals not to go extinct

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Everything begun at the Shedd Aquarium of Chicago. An animal trainer, Ken Ramirez, applied, although unknowingly, the theory of Nudges to make their life a bit easier and, in some cases, allow them to survive.

Ramirez is known, in his field, for having trained thousands of butterflies to perform a choreographed exhibition to the rhythm of music, in a botanical garden. But today his goal is not focusing on creating fun anymore, but protecting the wildlife, intervening on their habits and their behaviors. The approach is very much resemblant to Nudging strategies used by governments and organizations to lead human beings towards healthy and virtuous choices.

To train butterflies, Ramirez taught them to associate a stimulus (the flash of a light or a vibration) to a food reward. In this way, he made it possible for group of insects to fly in different directions, at specific times.

In Sierra Leone, instead, Ken helped rangers to protect a group of chimpanzees from poachers. Not every chimpanzee used to scream when a human approached it, and this prevented the rangers from hearing it in some cases. If only the whole group would have screamed in unison, the noise would have been intense enough to be heard.

This suggested a solution to Ramirez: installing containers from which fruit and insects would fall, near the trees where the monkeys would relax. When someone got close, the monkeys began to make noise and the rangers activated, through a remote control, the opening of the containers, distributing in this way food and insects. Chimpanzees learned quickly that the sequence “I scream – I get food” and began screaming at the sight of a human being.

In this way, poaching has been reduced by 86%.

Some examples of Nudges

Ramirez is not an academic, but this has not prevented him from realizing nudging interventions, getting the inspiration from what was already applied in other fields.

To favor the connection between different habitats, some actual privileged pathways have been created. But they were often ignored by animals. To encourage them, droppings and urine were spread along the way, in order to make them believe that other animals had already been on that path before, enticing them to do the same.

At Banff National Park, in Canada, biologists, to prevent grizzlies from being ran over by trains, placed along the railroad tracks a system of lights and bells that activated when a rail convoy was passing. Such a nudge has allowed bears, wolves, moose, small mammals and birds to get away from the tracks in time.

The share of animals that are killed by vehicles is estimated to be around 10%, including those species at risk of extinction, such as the Florida panther or the Indian elephant, so this could be a simple solution to implement.

To contain the voracity of cranes, known for pillaging farmers’ fields (a single bird can eat even 400 grains of wheat a day), electronic scarecrows were placed, to act as a deterrent, along with bait crops.

In Zambia, to discourage elephants from traversing through the Democratic Republic of Congo during their annual migration and fight poachers, Ramirez built some detours with trunks and trees and created artificial water ponds, able to attract the animals on the new path. The project has reached, with success, his third year.

Ken Ramirez applied the theory of Nudges to make animals' life a bit easier and in some cases allow them to survive.

Another intervention was realized to change the bad habits of Canadian brown bears. In the tourist city of Whistler, in British Columbia, every year millions of tourists visit the area and the rangers are forced to regularly shoot bears, because they are too dangerous for the public safety.

So, they thought to use a whistle as a warning, before shooting rubber pellets as they had always done. If the bear flees, a bell is sound to signal the averted danger and a shooting is avoided.

Not all interventions, sadly, have success and not every animal is inclined to gentle pushes, such as Nudges. In Australia, a specific type of marsupial at risk of extinction has learned to avoid eating a certain species of toad, which was toxic to him, after biologists fed it toad sausages soaked in a chemical substance that induced nausea. However, adding unpleasant substances to animal carcasses to try to persuade coyotes that livestock is not worth eating not always has prevented them from preying on sheep and cows.


Intervening in such an active way on habitats and habits has raised some doubts among the scientific community. In actuality, many animals would have not survived without Nudges.

Before releasing a rare species of Hawaiian crows to allow them to reproduce, they were taught open pods that contained food. Initially, the pods were presented opened, later partially closed, then fully closed. In the same way that wild animals move from an area to another, in many cases it is necessary to teach them new behaviors and habits to confront the new habitat.

Without taking into consideration how much we already influence the wild fauna with just our simple presence. Birds, in cities, sing in a different way to dampen the level of traffic noise. While foxes get braver.

Therefore, Nudges are useful, as long as they are implemented along with other strategies. If we want to keep bears out of towns, it is important for people, for example, to close securely their trash cans and keep their fruit trees safe, or the gentle push will hardly produce the awaited changes by itself.


Generally, animals are very receptive and learn quickly. The difference is how an act of persuasion is performed.

Let us not forget that Bornean orangutans have learned how to steal human boats, untying even the most complex knots: they steer them with their long arms and use the human fishing systems to eat the fish.

A flock of birds was able to avoid a storm that was distant 900 km, predicting its movement and escaping in time. The storm hit the USA in 2013, killing 25 people, and the birds that were studied all acted independently to avoid it. According to researchers, that hope one day to predict catastrophes such as this one studying the movement of birds, their ability to perceive ultrasounds is what put them on guard.

In China, for years they have been trying to understand what could make possible to predict an earthquake with snakes. A scientific study about the subject does not exist yet, but researchers are monitoring the behavior of these animals, that, they say, are able to predict an earthquake up to a distance of 120 km, trying to abandon their dens at all costs, even in full winter.

Who knows if a Nudge could be of help even in improving the predictive skills of birds and snakes? To benefit from it would surely be human beings too.

Laura Mondino


[2] Greggor A.L., Berger O., Blumstein D.T.,  The Rules of Attraction: The Necessary Role of Animal Cognition in Explaining Conservation Failures and Successes, Annual Review of Ecology, Evolution, and Systematics, 2020, 51:1, pp. 483-503

[3] Backs J.A., Nychka J.A., St. Clair C.C., Warning systems triggered by trains increase flight-initiation times of wildlife, Transport and Environment, Vol. 87, 2020

[4] Blackwell B.F., DeVault T.L., Fernández-Juricic E., Gese E.M., Gilbert-Norton L., Breck S.W., No single solution: application of behavioural principles in mitigating human–wildlife conflict, Animal Behaviour, Vol. 120, 2016, pp. 245-254



[7] Homstol L., Applications of learning theory to human-bear conflict: the efficacy of aversive conditioning and conditioned taste aversion, A thesis submitted to the Faculty of Graduate Studies and Research for the degree of Master of Science in Ecology, Department of Biological Sciences, Edmonton Alberta, 2011



[10] Berger-Tal O., Blumstein D.T., Swaisgood R.R., Conservation translocations: a review of common difficulties and promising directions, Animal Conservation, Vol. 23, Issue 2, April 2020, pp. 121-131

[11] Slabbekoorn H., Peet M., Birds sing at a higher pitch in urban noise. Nature 424, 267 (2003).

[12] Gil-Fernández M., Harcourt R., Newsome T., Towerton A., Carthey A., Adaptations of the red fox (Vulpes vulpes) to urban environments in Sydney, Australia, Journal of Urban Ecology, Vol. 6, Issue 1, 2020


[14] Streby H.M., Kramer G.R., et all, Tornadic storm avoidance behavior in breeding songbirds, Current Biology, Vol. 25, issue 1, pp. 98-102, 2005


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