DNA Explainer: How Pablo Escobar's 'Cocaine Hippos' became major threat in Columbia

The descendants of "cocaine hippos," originally owned by drug lord Pablo Escobar, pose a serious threat to both people and the environment in Colombia.

The size of the hippo population that is now presenting a threat to Colombia's native wildlife and plant life was underestimated by researchers. The administration wants to take drastic measures to reduce the population.

In the late 1980s, the cocaine tycoon Pablo Escobar imported a few African animals to Colombia. The creatures, however, were left to roam freely in a hot, marshy area of the Antioquia department following his passing in 1993, and environmental authorities have been powerless to control their population growth there.

According to Nature magazine,  the hippos (Hippopotamus amphibius) escaped from Pablo Escobar's mansion when he passed away and made their home in the Magdalena River. The huge herbivores have reproduced quickly to establish the greatest population of animals outside of Africa because they lack the original continent's natural predators or droughts to keep them in check.

Colombia attempted to manage the population by sterilising them, but it was unsuccessful. The hippos were designated as an invasive species by the environment ministry last year, which paved the way for a potential cull. However, the hippo transfer plan is considered a life-saving action.

In their native Africa, hippopotami kill more people than nearly any other animal, but in Colombia, they are well-liked members of the populace and a popular tourist destination.

However, the hippo population multiplied, and today there are about 200 of the two-ton animals roaming freely in northwest Colombia.

A few years ago, scientists predicted that in 2020 there would be roughly 98 hippos living alongside the country's Magdalena River and its tributaries based on how quickly the creatures were breeding. However, a team of researchers for a recent study estimated that there are 181-215 of animals living in Colombia after physically counting them, using a drone, and utilising other tracking techniques.

"Before, one argument against dealing with the hippos was that our information was limited and our arguments were theoretical," says ecologist Rafael Moreno, who participated in the study while at the Alexander von Humboldt Biological Resources Research Institute in Bogota. 

"But we have put that argument to bed now. This study shows that this is a real issue and that the state must act urgently."

According to a National University study, the number of hippos in the area could reach 1,000 by 2035.