N'DJAMENA (Reuters) - Two of six critically endangered black rhinos relocated to Chad in May have died, Zakouma National Park's management said, undermining efforts to restore their population in Chad after a nearly 50-year absence.
Before the transfer of the six rhinos from South Africa in May, the species had not been seen in Chad since 1972, mostly as a result of rampant poaching.
Across their habitat in southern, eastern and central Africa, poaching drove the black rhinos to near extinction. Their numbers fell by 98 percent between 1960 and 1998, but have doubled since then to about 5,400 due to conservation efforts.
In a statement over the weekend, African Parks, a non-profit organisation that runs Zakouma, said the carcasses of one male and one female rhino were discovered in separate locations in the park on Oct. 15.
It said the rhinos were not poached but that the exact cause of death was not yet known. Gilles Desesquelles, an African Parks representative, said a virus could be to blame.
The relocation of the rhinos from South Africa was intended to safeguard the species by expanding its geographic distribution, restore Zakouma's ecosystem and boost tourism to the 3,049 square-kilometre park.
Zakouma says it has mostly eliminated poaching since the end of a series of rebellions in Chad in 2009 and its famed elephant population -- 95 percent of which was poached between 2002-2010 -- is on the rise again.
(Reporting By Madjiasra Nako; Writing by Aaron Ross; Editing by Matthew Mpoke Bigg)