Pablo Escobar brought hippos to Colombia because he was building a private zoo on his massive estate, Hacienda Nápoles. In the early 1980s, at the peak of his power as head of the Medellín drug cartel, Escobar smuggled exotic animals from around the world onto the 5,500-acre property, including elephants, giraffes, ostriches, and four hippos: one male and three females. The zoo was a status symbol, a display of untouchable wealth, and a playground for Escobar and his family.
Why a Drug Lord Built a Zoo
Escobar was, at various points in the 1980s, one of the wealthiest people on Earth, and Hacienda Nápoles was his showcase. Located about 150 miles northwest of Bogotá in the Magdalena River valley, the estate featured a private airstrip, a sculpture park, luxury homes, and a full zoo stocked with animals illegally imported from Africa and elsewhere. Private exotic animal collections were a common vanity project among ultra-wealthy figures at the time, but Escobar’s operation was on a different scale. He had the money and the smuggling infrastructure to move large, dangerous animals across international borders with little concern for legality.
The zoo was open to the public, which fit Escobar’s broader strategy of cultivating a Robin Hood image among poor Colombians. Locals could visit and see animals they’d never otherwise encounter. For Escobar, the hippos were just one attraction among many.
What Happened After Escobar’s Death
When Escobar was killed by Colombian security forces in 1993, Hacienda Nápoles was abandoned. Most of the exotic animals either died from neglect or were transferred to legitimate zoos. The hippos, however, stayed. They were too large, too dangerous, and too difficult to transport. They sheltered in the estate’s lakes and waterways, and nobody had the resources or motivation to move them.
Colombia’s warm climate, abundant rivers, and lack of natural predators turned out to be ideal hippo habitat. The four original animals began breeding freely. In Africa, hippo populations are kept in check by droughts, territorial competition, and limited resources. In the Magdalena River basin, none of those pressures exist. The population has been growing at roughly 9.6% per year. By the start of 2022, researchers estimated there were about 91 hippos spread across the region, and the number has only climbed since.
An Ecological Problem With No Easy Fix
What started as a curiosity has become a genuine environmental crisis. A single hippo produces up to 13 pounds of waste per day, and that waste flows into rivers and lakes, dramatically altering nutrient levels in the water. The excess nutrients fuel algae growth, deplete oxygen, and can trigger massive fish kills. Native species, including fish populations that local communities depend on for their livelihoods, are suffering.
Hippo attacks on people have also become more common as the animals spread into new territory. They are highly territorial and aggressive, particularly at night. Residents in the state of Antioquia have described growing fear of encountering hippos on roads and near waterways. Colombia logged its first hippo-caused traffic accident when a car hit one of the animals at high speed, destroying the vehicle and killing the two-tonne hippo. A community leader near the crash site put it bluntly: “Everyone around here is terrified because we are flooded with these hippopotamuses. Now we’re at the point where we can’t even go out at night any more.”
Colombia’s Management Options
In March 2022, Colombia’s Ministry of Environment officially declared the hippos an invasive species, opening the legal door to population control measures. But deciding what to do has been deeply contentious.
Researchers have modeled four main strategies. Surgical sterilization of males would cost an estimated $530,000 for the roughly 42 males in the population as of early 2022, but it’s slow, risky for veterinary teams, and doesn’t reduce the existing population. Dart-based contraceptive vaccines are being tested, but treating the entire population would need to continue for 45 consecutive years to achieve eradication, at a cost of around $850,000. Feed-based oral contraceptives are even more expensive at $4.59 million over the same timeline, partly because you can’t control which animals eat the treated food. Euthanasia is the cheapest and fastest option at roughly $610,000 for the current population, but it faces intense public opposition. Many Colombians have grown attached to the hippos, and animal welfare organizations have pushed back hard against culling.
Colombian officials have also explored exporting hippos to sanctuaries in countries including India and Mexico, but that option would cost an estimated $3.5 million and involves complex international negotiations that have moved slowly.
Why the Problem Keeps Growing
The core challenge is math. At nearly 10% annual growth, every year of delay makes the problem significantly harder and more expensive to solve. Researchers have described the situation as a “narrow window” for control. If action isn’t taken soon, the population could reach hundreds within a couple of decades, spreading further along the Magdalena River system and becoming functionally impossible to manage.
All of this traces back to four hippos smuggled onto a drug lord’s estate over 40 years ago. Escobar almost certainly never imagined that his exotic pets would become one of the most complex invasive species problems in the Western Hemisphere. The hippos are now the largest wild population outside of Africa, thriving in a landscape that was never meant for them.