9. Snake Eradication Plan Backfires
In the days of the British Raj, India’s colonial rulers grew concerned by large numbers of venomous cobra snakes infesting the city of Delhi. So the authorities offered a bounty for every dead cobra, payable upon delivery of its skin to designated officials. The plan seemed to be working great, and before long, natives were thronging to the drop-off points, whose store rooms were soon bulging with cobra skins. However, the incentive scheme did not seem to have a noticeable effect on the city’s cobra population. No matter how many cobra skins were delivered to the authorities, Delhi seemed to be just as infested with the deadly snakes.
City officials eventually figured out why: many locals had turned to farming cobras. Since the bounty on the snake skin was greater than the cost of raising a cobra, the British had unintentionally created a new cash crop. When the authorities finally realized what was going on, and how their incentive scheme was being gamed, they canceled the plan, and stopped paying out bounties for cobra skins. That turned out to be their second mistake. Without the bounties, cobra skins and captive cobras were now worthless. So Delhi’s cobra farmers did the economically sensible thing, and released the snakes back into the wild – the “wild” in this case being the city of Delhi. The snake infestation was increased by orders of magnitude, and Delhi wound up with many times more cobras than it had possessed before the authorities launched their ill-advised plan.