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The struggle in managing Pablo Escobar’s ‘cocaine hippos’

Efforts to cull or relocate the population have created controversy in Columbia

At the end of last year, Colombian authorities declared war on the approximately 200 cocaine hippos wreaking havoc in the nation’s largest river system. This sentence may seem as if it belongs in a lost Gabriel García Márquez novel, one in which he toned down the magical realism and ramped up the dystopian satire.

However, as García Márquez once told an interviewer: “There’s not a single line in all my work that does not have a basis in reality. The problem is that Caribbean reality resembles the wildest imagination.”

What is the reality of the cocaine hippos, and how they did they arrive in the Rio Magdalena basin? The current population can be traced to four animals that belonged to drug lord Pablo Escobar. Head of the Medellín cartel, Escobar spent the 1980s smuggling cocaine into the United States and amassing an incredible fortune. When Forbes magazine launched its annual billionaires list in 1987, Escobar was on it, with an estimated net worth of more than $2 billion (about €5 billion today) and remained listed until his death in 1993.

Escobar’s income was so vast that he had to spend €2,500 each month on elastic bands to stack bills. He was able to pay off, or pay to have killed, any threats from the Colombian government. He also built significant amounts of housing and infrastructure, allowing him to cultivate a Robin Hood image somewhat at odds with the reality of a man who blew up a civilian passenger jet in an attempt to kill a political rival. Escobar’s wealth was reflected in his vast country estate, Hacienda Nápoles, which featured a private airport, racetrack and zoo.


While Escobar’s wealth came from exporting, one of his few serious clashes with the authorities came when he attempted to import a variety of exotic animals for the zoo. Eventually, however, it boasted elephants, giraffes, and hippos, most of which were seized along with Escobar’s property. The hippos proved difficult to capture and were left to fend for themselves. With no natural predators, they quickly multiplied and spread into the surrounding countryside. Efforts to cull or relocate the population have created controversy and other attempts to manage them have proved expensive and of limited benefit to a resource-constrained Colombian government.

The cocaine hippos are not the first instance of exotic pets becoming an invasive species, or of government mismanagement causing population imbalances. In 1958, Mao Zedong, former head of state in the Chinese People’s Republic, identified sparrows as one of four pests to be eliminated as part of a public health campaign in China. Sparrows were assumed to be a threat to stored grain but were crucial in controlling pests such as locusts. Their widespread elimination led to crop devastation and exacerbated a famine from 1958-1962 that saw between 20-30 million Chinese deaths.

In 1902, French colonial rulers in Hanoi attempted to control an outbreak of bubonic plague by offering a bounty for rat tails. The rats had spread through Hanoi’s new sewer system, an environment in which they had no natural predators and could quickly multiply. French officials noticed that the problem seemed to get worse and soon spotted large numbers of tailless rats as enterprising locals had realised that allowing captured rats to breed would allow them to collect more tails than simply killing them. Similar stories exist about a cobra bounty in British India, although strong evidence that Indian farmers began breeding cobras is difficult to find.

One snake bounty that definitely does exist is an elimination programme in Florida. Burmese pythons have become a problematic invasive species in the Everglades; like Escobar’s hippos they began as exotic pets but when released quickly outcompeted the native fauna. Hunters are now paid a salary by the state to find and eliminate them.

Escobar’s hippos are one particularly striking example of how carefully imported animals must be managed. Animals with no obvious predators can quickly disrupt a local ecosystem. But, human efforts at population control need to be managed carefully, or they can generate perverse incentives and disastrous unintended consequences. Whether the current attempts by the Colombian government will prove successful remains to be seen, but at the very least it would seem impractical to exploit any reward through hippo farming.

Stuart Mathieson is a postdoctoral fellow in the school of history and geography at Dublin City University

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