Six critically endangered black rhinos were en route from South Africa to Chad on Thursday in a pioneering project to re-introduce the animals to a country where they were wiped out by poaching nearly 50 years ago.
The wild black rhinos were loaded onto a plane at Port Elizabeth airport on the South African coast in a 3,000-mile (4,800-kilometre) journey to Chad's Zakouma National Park.
After the translocation, which took two years of planning, the rhinos will be released into small enclosures before being allowed to roam freely through the vast park.
Security has been strengthened at Zakouma, in the south of Chad, with officials saying that poaching has been "practically eliminated" thanks to African Parks, an international conservation group.
"All too often, headlines on rhinos are about their demise as they teeter on the brink of extinction," said African Parks chief Peter Fearnhead.
"However, today we are participating in an historic event and peering into a brighter future for this species which has persisted on this planet for millions of years."
The four females and two males were taken by road from the Addo park in South Africa to the airport in special ventilated crates that were loaded into the plane by a crane.
Teams of vets monitored the animals' stress levels.
'Truly hopeful story'
Fernhead said the project was a "truly hopeful story for rhinos across Africa", and that it would encourage population growth and boost biodiversity in Chad.
Fewer than 25,000 rhinos, of which just 5,000 are black rhinos, remain in the wild in Africa due to a surge in poaching.
Black rhinos are rated as critically endangered by the International Union for Conservation of Nature.
Rhinos are targeted to feed a booming demand for rhino horn in China, Vietnam and other Asian countries, where it is believed to have medicinal qualities.
Northern white rhinos disappeared from Chad several decades ago and the last western black rhino was recorded there in 1972, after decades of poaching pushed both subspecies to local extinction.
African Parks assumed management of Zakouma in 2010 and secured the park from poaching, allowing wild animals to thrive.
The park has a dedicated rhino ranger unit to ensure the animals will be protected, as well as a well-equipped law enforcement team and aerial surveillance.
"It is a mark of the strength of our partnership with African Parks and the transformation of Zakouma in to a secure sanctuary that we are now able to bring rhinos back," said Chad's ambassador to South Africa Youssouf Mahamat Itno.
African Parks reintroduced rhinos to Rwanda in 2017.
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