WaPo:
in the 1980s, drug kingpin Pablo Escobar smuggled four hippos onto his private country estate. Now dozens of its wild spawn roam the wetlands north of Bogota
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Now a study forecasts that the invasive hippo population will swell to almost 1,500 individuals by 2040. At that point, their environmental impacts will be irreversible and their numbers impossible to control
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It was hard enough to find the hippo, a massive, ornery male with a reputation for harassing local ranchers. For three long months, the scientists tracked it through the Colombian countryside, staking out lakes, traipsing through brush and camping on nearby farms.
But castrating it — that was an almost herculean task. They had to inject it with a potent elephant tranquilizer before it was safe to approach. Even with the hippo immobilized, it was surprisingly difficult to locate his, ahem, parts.
“It was horrible”
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“I didn’t know they could jump”