Via the Save The Rhino monthly newsletter we have a report at ETN on the progress of the Northern White Rhinos released this year in Kenya.

The Northern White Rhinos, donated by the Czech government in December of last year, have now started to roam freely on the Ol Pejeta Conservancy after being released from their smaller "bomas" into the wider area.
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Richard Vigne, CEO of the Ol Pejeta Conservancy, has made it clear that they will be breeding hybrids for a while before sufficient numbers will then permit to cross them back towards nearly pure Northern White.