The Bounty Backfire

Offering cash rewards for dangerous pests sounds like a remarkably straightforward way to solve a problem. You pay for dead pests, the pests disappear, and everyone goes home richer and safer. But human beings are relentlessly rational. The moment a pest becomes a commodity, its eradication ceases to be the goal of the people tasked with catching it. Instead, the pest becomes an income stream, and a sustainable income stream requires a reliable supply.

During the 1902 rat infestation in Hanoi, the French colonial government discovered just how creative that rationality could be. They implemented a bounty program paid per rat tail. Before long, colonial officials noticed something unsettling roaming the streets: tailless rats. Citizens had figured out that killing the rat ended the supply, whereas releasing the tailless rat allowed it to live, breed, and keep the bounty production line moving. A similar, though historically contested, legend haunts the British Raj in Delhi, where locals allegedly bred cobras for bounty payments and dumped them back into the wild once the government caught on and canceled the program.

This phenomenon, known as the Cobra Effect, reveals a recurring blind spot in top-down problem solving. When incentives fail to account for socioeconomic realities, they reward the symptom while preserving the disease. If your livelihood depends on a creature's existence, you have very little economic incentive to see it go extinct.