Six critically endangered black rhinos are being transported from South Africa to Chad, restoring the species to the country in north-central Africa nearly half a century after it was wiped out there.African Parks, a Johannesburg-based conservation group, said on Thursday that the rhinos will travel by air to Zakouma National Park, a reserve in Chad that it manages with the government.The group says the goal is to help the long-term survival of black rhinos and to restore biodiversity in Chad. It says there are fewer than 25 000 rhinos in the African wild, of which about 20% are black rhinos and the rest white rhinos.Most of the rhinos are in South Africa, though the population has been hit hard by poachers supplying horns to an illegal Asian market.Watch now: The rare black rhino is being returned to the nation of Chad. “Usually headlines on rhinos are about their demise; today it is about their brighter future” said CEO of @AfricanParks Peter Fearnhead on the return of rhinos to Zakouma pic.twitter.com/ceZsnpomNJ— African Parks (@AfricanParks) May 3, 2018 The relocation of the animals is the result of a custodian agreement between South Africa and Chad. Conservationists say the rhino population in Africa will grow again. During the past 10 years poachers have killed more than seven thousand rhinos on the continent. #sabcnews pic.twitter.com/LpgSLlnqDl— Jayed- Leigh Paulse (@JayedLeigh) May 3, 20186 black rhinos are being flown to Chad, reintroducing the critically endangered species there 50 years after they were wiped out.Black rhino populations dropped 98% between 1960-1995 mainly due to poaching. There are currently only about 5,400. pic.twitter.com/uRDi3pTLiP— AJ+ (@ajplus) May 3, 2018Nearly 50 years after they were hunted to local extinction, rhinoceroses are returning to Chad, with six rhinos being airlifted from South Africa to Chad’s Zakouma National Park. https://t.co/NXLn3eODbi pic.twitter.com/ji97APMvoI— Yale Environment 360 (@YaleE360) May 3, 2018Black rhino are returning to the Zakouma National Park in Chad for the first time in 45 years.Six of the endangered animals are being translocated from the Addo National Elephant park in the Eastern Cape.#SabcNews pic.twitter.com/1fetkYMp1I— Jayed- Leigh Paulse (@JayedLeigh) May 3, 2018@SANParks Rhinos being loaded into the aircraft at the PE Airport from Addo Elephant National Park #RhinosToChad #Rhinos4Africa pic.twitter.com/z4j5WaDHNH— Environmentza (@environmentza) May 3, 2018* Sign up to News24's top Africa news in your inbox: SUBSCRIBE TO THE HELLO AFRICA NEWSLETTERFOLLOW News24 Africa on Twitter and Facebook.