In a desperate bid to preserve a critically endangered species, a U.S. zoo is taking the controversial step of trying to mate brother and sister captive Sumatran rhinoceroses. The coupling of six-year-old Harapan and his older sister Suci could take place as early as in August at the Cincinnati Zoo in Ohio, animal keepers say. The tactic has stirred strong emotions, but Terri Roth, director of the Lindner Center for Conservation and Research of Endangered Wildlife, said she has no other choice. Conservation experts say there are as few as 100 Sumatran rhinos left in the wild in their native lands of Indonesia and Malaysia. In captivity, there are only 10 in the world. Four of them are closely related. For Suci, who is marking her ninth birthday next week, the only available suitors are her relatives, Ms. Roth said. Harapan, who is said to be on the cusp of adulthood, was brought to Ohio earlier this month from his previous home at the Los Angeles Zoo. — AFP