It's not impossible that there could be as few as 8 surviving animals, in which case the current European zoo population could be 25% of the surviving population, and the North American zoo animals another 25%. The other 50% are at Ol Pejeta Conservancy in Kenya. I understand no fully-wild animals have been sighted for some years. It's all rather tragic - as the Czech and US animals are beyond breeding, the fate of the whole subpecies rests with four animals (2.2) at Ol Pejeta (the animals moved from Dvur Kralove).
Needless to say, anything beyond a slight stay of execution through one more generation would be a miracle.
