Ten rhinos have been safely released in northern Botswana, after a long journey that entailed a cargo plane, a crane, dozens of soldiers, and six weeks in quarantine.

The animals were captured from an overpopulated park in South Africa and were moved to an undisclosed location in a sparsely populated reserve in Botswana last week that is better protected from poachers.

The relocation project, called Rhinos Without Borders, aims to move 100 rhinos by next year, the largest attempted airlift of rhinos in history.

The first ten were released on April 28, after touching down in the largest aircraft ever to land at Botswana's Maun International Airport, an Ilyushin 76, according to Dereck Joubert, one of the project's leaders.

“It was a great success and we are all feeling euphoric from the amazing experience,” Beverly Joubert, another project leader, said via email.

Dereck Joubert says the bold project is necessary because rhinos reached a tipping point last year, with more killed by poachers than were born in the wild. An estimated 4,000 to 5,000 black rhinos and 20,000 white rhinos remain in Africa, with another one killed by poachers every seven and a half hours. Their horns are hacked off and sold in China and Vietnam on the black market for medical treatments that western scientists say don't work.

Big Effort

Getting the rhinos from the airport to deep into the Okavango Delta was no easy task. Already packed in crates, the rhinos were loaded onto trucks and escorted by 60 soldiers, to deter potential poachers. (Learn more about the process.)

Along the way, a wheel came off one of the trucks and the two-ton rhinos had to be moved into another truck via crane. The convoy had to cross several rivers, while a helicopter was sent ahead to scout for poachers. The heat was a relentless 90 degrees Fahrenheit (32 Celsius), which meant the team had to make sure the animals didn’t overheat.

By sundown, the rhinos were released into their new homes, less than 24 hours from the start of their journey from the staging area in an undisclosed part of South Africa. There, the rhinos had been monitored for disease for six weeks and fitted with microchips to monitor their locations. But under the watchful eye of the Botswana military, the rhinos “finally ran free,” says Dereck Joubert.

“One bull [male rhino] turned back and as a deep sign of appreciation charged the container he had been cooped up in, putting a massive dent in it,” says Joubert. (Learn about the controversy around legal rhino hunting.)

The relocation process is expensive, about $45,000 per rhino, but Rhinos Without Borders has raised hundreds of thousands of dollars from supporters and will soon be moving more rhinos.