Pablo Escobar, Colombia's notorious drug lord and a symbol the country is still trying to shake, had a penchant for collecting exotic animals.
On his Hacienda Napoles estate, located right between Bogotá and Medellín, he built a bootleg zoo filled with tigers, zebras, monkeys and other animals. But after he was killed in 1993, many of his animals lived on.
Most were donated to international and Colombian zoos, but his four hippopotamuses, imported from California, were left to roam free.
Today, the herd has multiplied to somewhere around 40 hippos, making it the largest wild hippo herd outside of Africa.
"When it comes to the direct relationship they have with the hippos, the region has adopted a relationship of profound respect and admiration for the hippos in the area," says Oberdan Martinez, the general manager of the park.
The problem is that the park has not always been able to contain the animals. They live in a limbo between cages and full freedom, with loose boundaries of fences and natural barriers surrounding the lake that they live in (except for one hippo named Vanessa, who lives inside a defined fence; she was rejected by her family at birth). Local fishermen started spotting them in rivers as far as 100 miles away in 2007, and there were multiple reported sightings of hippos in nearby towns in 2016.
And since they are not native to Colombia, there are no natural predators for the hippos there. They are a deadly animal, killing 3,000 people annually in Africa, but there have miraculously been zero reported deaths by hippo in Colombia.
"They're reproducing uncontrollably and they aren't native of this country, so it's something that we need to manage," says Martinez.
The park and Cornare has started a sterilization campaign, but it's not an easy one. A male hippo's testicles are retracted, or "hidden" inside of their bodies, and only four of the hippos have been successfully castrated.
"They're gorgeous animals, but just to observe and respect," says Martinez. "It's not good that we live with them in their own habitat. It's beautiful, but from a distance."
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