Colombian officials have authorized a plan to cull dozens of hippos descended from animals brought to the country in the 1980s by Pablo Escobar, after the feral beasts displaced native species and threatened local villagers.

The environment minister, Irene Vélez, said the decision was reached because other methods to control their population had been expensive and unsuccessful, including neutering some of the animals or moving them to zoos. Vélez said that up to 80 hippos would be affected by the measure. She did not say when the hunting would begin.

“If we don’t do this we will not be able to control the population,” Vélez said. “We have to take this action to preserve our ecosystems.”

Colombia is the only country outside Africa with a wild hippo population, which descends entirely from four individuals imported by Escobar in the 1980s as the drug lord built a private zoo in Hacienda Nápoles, a gigantic ranch in the Magdalena River valley.

A study published by Colombia’s National University estimated that about 170 hippos were roaming freely in the country in 2022.

Recently, hippos have been spotted in areas that are more than 100km (60 miles) north of the ranch, where Escobar initially introduced the water-dwelling pachyderms.

Environmental authorities in Colombia say the large mammals pose a threat to villagers who have encountered them in farms and rivers. They also compete for food and space against local species such as river manatees.

Despite the environmental challenges, the hippos have also become a tourist attraction, with residents of the villages surrounding Hacienda Nápoles now offering hippo spotting tours and selling hippo-themed souvenirs.

The hippos are also one of the main attractions at the Nápoles ranch, which was confiscated by Colombia’s government as it seized Escobar’s properties. It now functions as a theme park, featuring swimming spools, water slides and a zoo that includes several other African species.

Animal welfare activists in Colombia have long opposed proposals to kill the hippos, arguing they deserve to live, and adding that addressing the problem through violence sets a poor example for a country that has gone through decades of internal conflict.

Over the past 12 years, a period spanning three different presidential administrations, Colombia has tried to neuter some of the hippos in an effort to reduce their population. But these initiatives have had a limited scope, due to the high costs that come with capturing the dangerous animals, and performing surgeries on them.

Because Colombia’s hippos come from a limited gene pool, and could carry diseases, taking them back to their natural habitat in Africa is also unfeasible.