In general, scientists are not fond of Pablo Escobar’s hippos.
When the Colombian National Police killed the cocaine kingpin in 1993, he left behind four adult hippos. They are considered to be one of the world top invasive species. A January study found that their shit contributed to algal blooms and screwing with the chemistry of local lakes–The implication is that the animals are gross pests that can ruin local ecosystems.
But in one new study, published Monday in Proceedings of the National Academy of Science, takes a different view of the coke hippos. In particular, the new research shows that the introduction of large non-native herbivores into ecosystems – such as Colombia’s hippos – can restore ecologically beneficial properties in the area that may have been lost for thousands of years.
“While we found that some introduced herbivores are perfect ecological similarities for extinct species, in others, the introduced species represents a mix of traits seen in extinct species,” study co-author John Rowan, a co-author of the study, and biology researcher at the University of Massachusetts Amherst, said in a statement.
For example, Pablo’s hippos are similar in diet and size to the now-extinct giant llamas that once roamed the area. They are also similar in size and semi-aquatic behavior to another extinct species, does not register, which have been gone for thousands of years. That allows them to fill two long vacant roles in the Colombian ecosystem to which they were introduced after Escobar died and started roaming the countryside.
In other words, Pablo Escobar is unintentionally responsible for rebuilding his homeland and bringing back ecosystem services that have been missing since the extinction of this megafauna. That doesn’t necessarily mean that Pablo’s hippos are good. But it does mean that scientists should look at introduced species like the hippopotamus without presuming negative invasive pests (locals can beg).
And this isn’t just about Pablo’s hippos. The researchers analyzed 72 cases of invasive – or ‘introduced’, as the authors say – herbivorous species entering an ecosystem, comparing their ecological properties to those of the animals populating the areas in the prehistoric, pre-human past.
In 64 percent of cases, the authors found that introduced species looked more like extinct species than those currently populating an ecosystem. That means these introduced species can potentially fill more than half the time in long-empty ecological niches, which can affect various aspects of ecosystem health, from which nutrients are distributed in the water and soil to how often prevent forest fires.
For example, the hippos are thought to be harmful because their poop fertilizes lakes. But “in Africa, fertilizing waterways that lead hippos plays a key role in increasing fishing productivity,” Erick Lundgren, a Ph.D. student at the UTS Center for Compassionate Conservation who led the study, Earther said. Indeed.
“We don’t claim that hippos are beneficial or not – but that they should be studied in the context of deep time without those kinds of labels,” Lundgren said.