Scientists are growing concerned about the rising population of hippopotamuses that were introduced to Colombia back in the 1980s by drug kingpin Pablo Escobar.
In a new study, published in the journal Biological Conservation, researchers from Mexican and Colombian universities said they are concerned over the hippos, — deemed the "largest invasive animal" in the world — their negative environmental impact, and the animals' threat to human safety.
The hippos, native to Africa, have extended from their original home and have "invaded" extensive areas of the Magdalena River basin in Colombia over the past several decades, the study said. Their population has also vastly increased: researchers believe there are about 80 hippos, ancestors of Escobar's former pets, roaming the country, up from 35 hippos counted in 2012.
According to Smithsonian Magazine, the hippos' feces fertilized the growth of cyanobacteria, also known as blue-green algae, in the water they reside in, posing a serious danger to humans and other animals, as well as the environment itself.
The study also mentioned violent encounters occurring between humans and hippos in the past, citing an incident in May 2020 in which a 45-year-old male was seriously injured after a hippo attacked him in Puerto Triunfo.
As a solution, researchers in the study suggested that the hippos be culled to preserve the local ecosystem and prevent long-term negative effects.
"Our models predicted that the worst-case scenario would occur if no management strategies are implemented: the population will continue positively growing, with potential ecologic and socio-economic long-lasting negative effects," the conclusion of the study stated.
Researchers also believe that over time, the hippos' aggressions may "become increasingly frequent, thus augmenting the likelihood of human fatalities"
In the 1980s, Escobar illegally imported several species of exotic animals to Colombia to establish a private zoo at his 7,000-acre ranch, Hacienda Nápoles, located in the municipality of Puerto Triunfo. Among those animals were four hippos, one male and three female, from a United States zoo.
After Escobar was killed by the Colombian National Police in 1993, his ranch and personal zoo were seized by the authorities. And while most of Escobar's exotic animals were relocated, the four hippos were left in the wild because they were too difficult to capture, according to the study.
As the hippo population continued to rise in Colombia over the years, the government attempted to cull the animals but were halted due to demands from locals, as well as environmental law protections.