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Drug baron's hippos at large in Colombia - 22nd February 2021

Illegally imported hippos released from the private zoo of Pablo Escobar, the 20th century’s most prominent narcoterrorist, are now threatening Colombia’s aquatic ecosystems. The offspring of Escobar’s four hippopotamuses have flourished thanks to the tropical conditions of the River Magdalena and the lack of natural predators.

According to findings recently published in a leading conservation journal, selective culling might be conservationists’ only option to mitigate the hippos’ environmental impact.

The focus of an international manhunt following his escape from custody, the Medellin cartel kingpin was shot dead in 1993. His palatial residence 250 kilometres north-west of Bogota, which housed the illegal zoo, was seized by the authorities. They ensured its inhabitants were dispatched to new surroundings, except for the hippos.

"It was logistically difficult to move them around, so the authorities just left them there, probably thinking the animals would die," explains Colombian zoologist Nataly Castelblanco.

The thriving hippo population has led Castelblanco to argue that without an annual cull of 30 animals, numbers may balloon to 1,400 specimens by 2034. This extraordinary proliferation from Escobar’s meagre herd of one male and three females is largely down to the absence of natural predators to balance their presence. In addition, the Colombian climate offers a more habitable contrast to their native African lands, where the population is kept in check by seasonal droughts.

The hippos' mammoth impact on local ecosystems is already displacing the indigenous manatee, currently on the verge of extinction. They could also endanger fisheries by altering the chemical makeup of waterways, and humans too, as they stand among the world’s most threatening beasts.

Following media coverage of the study, Castelblanco has been verbally assaulted and even received death threats. "Some people in Colombia can get very angry when they talk about the hippos," she remarked.

"People tend to understand much more about invasive species when we talk about plants or smaller creatures, instead of a massive mammal that many may find cute."