Colombia is dealing with an invasive population of hippos. Yes, hippos. It’s a wild story: In the late 1970s, drug cartel czar Pablo Escobar imported four hippopotamuses—three female and one male—to a private estate in western Colombia. In the early 1990s, when Escobar finally surrendered to authorities, the Colombian government seized his estate—and let the hippos loose.

Since then, they reproduced. Quickly. According to The Washington Post, there are now more than 130 free-roaming “cocaine hippos” living along the Magdalena River in central Colombia. Native to Africa, the species has no natural predators in South America. Like wild “super pigs” in Canada, they are reportedly pushing out native species, polluting the soil and water, and being aggressive toward people. (There’s a reason they’re considered one of the most dangerous game animals on the planet). If left unchecked, experts say the population could reach 600 hippos in the next 15 years.

Authorities have so far struggled to respond. In a 2009 controlled hunt, a hunter pursued and killed one of the hippos while being guided by members of the military. But a public outcry over an ensuing trophy photo made politicians averse to the population management strategy—and in the meantime, the hippo population exploded.

In recent years, officials have undertaken hippo sterilization efforts with little success. As with urban deer populations in the U.S., the efforts have proven costly for only temporary effectiveness. Last year, local authorities reportedly darted 38 hippos with contraceptives, but they may have darted the same hippo several times because they were unable to differentiate among the individuals.

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Now, Colombian authorities have concocted a new management approach. According to the Associated Press, the government plans on capturing at least 70 hippos and transferring them to sanctuaries and zoos in India and Mexico. The plan comes with a high price tag and it remains to be seen if it will be successful. Each hippo will need to be contained in a custom enclosure that costs $10,000. Chartering a plane capable of carrying 20 to 30 hippos will then cost around $400,000 for a flight to Mexico and $900,000 to India.