(Newser) – Colombia is facing an overpopulation issue: a famed drug lord’s herd of hippos keeps expanding. Pablo Escobar built himself a zoo in the 1980s, smuggling in a host of exotic animals, including one male and three female hippos. Now, 20 years after the drug boss’s death, the hippos have found a welcoming climate—free of the drought that helps curb herd size in Africa—and apparently an appetite for sex. Estimates say there are now between 50 and 60 hippos (in 2006, the LAT pegged their population at 16), most living in one of 12 man-made lakes at Escobar’s former ranch. But a dozen have been confirmed as having broken away and into the nearby Magdalena River, meaning there could be many more; in 2009, one hippo was located 62 miles away.

While hippos in Africa tend to become sexually active as early as age seven for males and nine for females, the hippos in Colombia are breeding as early as three, the BBC reports. “It’s just like this crazy wildlife experiment that we’re left with,” says a San Diego University ecologist. “Gosh! I hope this goes well.” So far, it doesn’t seem to be. The beasts are terrifying fishermen, wreaking havoc on crops, and even crushing small cows. They can’t be moved back to Africa due to the possibility they carry disease, zoos aren’t interested in the adults, a reserve with hippo-proof fences would cost about $500,000, and castration would be expensive and risky for both the vets and the creatures, who the ecologist notes are highly sensitive to sedation. So how would a biologist working in the Amazon region solve the issue? “I think they should barbecue them and eat them,” he says. He isn’t kidding.