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People in a small Colombian town are reporting increased sightings of hippopotamuses in the area.
The hippopotamus is native to Africa, not South America. But a local population of the animals developed from a private collection brought to Colombia by infamous drug trafficker Pablo Escobar. Escobar was the leader of Colombia's Medellin drug cartel.
At least 80 hippopotamuses are estimated to live around the rural town of Doradal, about 140 kilometers east of Medellin. The town is near Escobar's former private estate, covering about 2,225 hectares.
In the 1980s, during the height of his power, Escobar kept the hippos on the property in a private zoo, along with other animals such as elephants and giraffes.
Following Escobar's death in 1993, most of the animals from the zoo were taken to new homes or died. But because the hippos were difficult and costly to transport, they were left in the area.
Conditions in the area are favorable for the hippos. They live in nearby lakes and waterways, enjoy endless feeding on grass and have no natural predators.
One of the first hippo sightings in Doradal came in 2018. Since then, the animals have continued coming. Officials are worried that they could one day attack members of the local population.
Large hippos can weigh several tons and can be aggressive. The animals kill more people a year in Africa than any other kind of wildlife. Scientists say the presence of hippos in Colombia also threatens the other animals and plant life.
Students who attend a small school behind Escobar's former property arrive for class each day passing a sign that reads "danger - hippopotamus present."
"It worries us," said Wilber Quinones, a teacher at the school. "We have to lock ourselves inside with the children to try and avoid an accident."
So far, the hippos around Doradal have not attacked any humans. But as their numbers grow and they expand into more populated areas, experts fear an attack is more likely.
However, many people enjoy looking at the hippos. The animals have even brought new visitors into the area. Stores throughout the town sell tourist items related to the animals.
A new study by researchers at the University of California, San Diego, UCSD, found that the hippos are changing the quality of the water in which they spend much of their time. The hippos feed at night and then spend the day cooling off in the water, where they release bodily waste.
Scientists have warned that such waste can cause harmful growth and bacteria to develop in lakes in the area. The concerns have led local officials to seek new solutions to the hippopotamus problem.
The local environmental agency responsible for the area, Cornare, is working to find a solution that is acceptable to people in the area, but that will also treat the animals in a humane way.
Gina Serna is a specialist with Cornare. She is helping lead the project. She told the AP she thinks the hippopotamus situation has become an "urgent" issue.
"We already have a report of a family of hippopotamuses in the Magdalena river," Serna said. "The Magdalena connects almost all of Colombia, so they could move into any part of the country."
One plan is to sterilize the hippos. Last year, Serna and a group from Cornare carried out a successful in-the-wild surgical sterilization of a female hippo, the first ever in Colombia.
Later this year, the group plans to attempt several more sterilizations, as well as a chemical sterilization method that has proven successful in pigs.
I'm Bryan Lynn.
The Associated Press reported on this story. Bryan Lynn adapted the report for VOA Learning English. Ashley Thompson was the editor.
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