The son of an Indian billionaire has offered to take in 80 hippos from Colombia after officials there recently approved a plan to euthanise the animals whose population is expected to exceed 500 by 2030 without intervention.

The hippos, an invasive species in Colombia, are part of a population of 200 that continues to reproduce unchecked. They are the offspring of animals illegally brought to the country in the 1980s by the late drug kingpin Pablo Escobar for his private zoo at Hacienda Nápoles – a sprawling valley estate that featured a private airstrip and served as his secluded fortress.

After his death in 1993, most of the animals were relocated, but the animals, dubbed “cocaine hippos” locally, were left behind because they were difficult to move.

Anant Ambani, the son of tycoon Mukesh Ambani, has formally requested the Colombian government for the translocation of the 80 animals to his animal centre, Vantara, located in Jamnagar in the western Indian state of Gujarat.

With no natural predators and plenty of water in Colombia’s rivers, the hippos began to breed rapidly. From just four, the population has grown to over 100 and is still expanding.

Earlier this month, the Colombian government approved plans to cull those hippos after previous attempts to control the population, including castration, proved too expensive or ineffective.

Mr Ambani, the CEO of the private Vantara zoo, has written a letter to Colombia’s environment ministry to “suspend the proposed decision to euthanise 80 hippopotamuses in the Magdalena River basin”.

The government has been urged to consider the proposal to relocate them to Vantara for their “lifelong care”, the letter shared on the zoo’s social media accounts said.

Vantara zoo boasts of 2,500 acres of land and houses up to 2,000 species of animals, including elephants and tigers. The zoo, home to more than 150,000 animals, has faced controversy and criticism over allegations of sourcing its animals from Indian states involving precarious journeys.

Previously, a coalition of South African animal rights groups called on their government to investigate the alleged exports of wild animals to Vantara on the recommendation of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) – a multilateral treaty to protect endangered plants and animals from international trade. But it later reversed the recommendation after some countries, including India, the US, Japan and Brazil said the measure was too premature, with some also saying there was no evidence of illegal imports into India. An investigation last year by India’s Supreme Court also exonerated Vantara of wrongdoing.

The zoo is not open to the public but has seen guided high-profile visits by Lionel Messi, Bill Gates, Mark Zuckerberg, and other influential people. The project is also supported by Indian prime minister Narendra Modi.

The zoo is situated in the Jamnagar industrial area, alongside the Reliance Jamnagar Refinery Complex, which the conglomerate says is the world's largest crude oil refinery. The temperatures in the region soar above 100 degrees Fahrenheit in the summer, and wildlife activists say it could get too hot for some of the animals. Vantara deny allegations of any wrongdoing.

It insists that: "Vantara has the expertise, infrastructure and resolve to support this effort, entirely on Colombia's terms.”

"These 80 hippos did not choose where they were born, nor did they create the circumstances they now face," Mr Ambani said. "They are living, sentient beings, and if we have the ability to save them through a safe and humane solution, we have a responsibility to try."

Colombia is the only country outside of Africa with a wild hippo population.

Escobar had a gigantic ranch in the Magdalena River valley with a private landing strip that served as his rural abode, about 250km north-west of the capital Bogotá. Since his death, the small herd of hippos has been allowed to roam freely and since then their population has exploded.

A study published by Colombia’s National University estimated that around 170 hippos were roaming freely in the country in 2022.

Environmental authorities in Colombia say the large mammals are invasive species and pose a threat to villagers who have encountered them in farms and rivers. They also compete for food and space against local species such as river manatees.

The letter said if the Colombian government approves the request, the translocation would be carried out “in strict accordance with the necessary approvals, permits, due diligence processes, biosecurity requirements, and logistical planning”.

It added that "at the heart of this proposal is Vantara's belief that every life matters and that we have a shared responsibility to protect life wherever possible".

Animal welfare activists in Colombia have vehemently opposed proposals to kill the hippos, arguing they deserve to live. They say addressing the problem through violence sets a poor example for a country that has gone through decades of internal conflict.

Amid the challenges posed by the animals, the hippos have become a tourist attraction and source of income to the residents of the villages surrounding Hacienda Nápoles, who offer hippo spotting tours and sell hippo-themed souvenirs to tourists.

The hippos have also become a major draw at the Nápoles ranch, once seized by the Colombian government as part of its takeover of Escobar’s assets. Today, the site operates as a theme park, complete with swimming pools, water slides, and a zoo housing several other African species.

Announcing the decision to cull 80 hippos, environment minister Irene Vélez Torres said: “Without this action, it is impossible to control the population, and as we have already seen, estimates imply that by 2030 we would have at least 500 hippos affecting our ecosystems and native species, such as the manatee and the river turtle.”

“It is with responsibility for our ecosystem that we must take these actions,” the minister said.

As of 17 April, Mukesh Ambani’s net worth stands at $90.8bn. Adani Group chair Gautam Adani has overtaken Mukesh Ambani, chairman and managing director of Reliance Industries (RIL), to become Asia’s richest person, according to Bloomberg Billionaires Index. Mr Adani’s wealth is estimated to be $92.6bn.