Despite the fact that the Sumatran rhino is in dire straits, the US zoo record with conservation breeding management ex situ was rather painfully slim and too many Sumatran rhinos got "consumed up" in it never to produce any offspring and passing on too early.
I am not saying it would have been any different had all rhinos stayed put in Indonesia - which I would have favoured then and (even) would advocate for now (with no more Sumatran rhinos ever to leave the island of Sumatera or Kalimantan). There is no crystal ball to predict what would have happened had the program stayed in Indonesia and Malaysia long term with support from the International zoo community in capacity building, research, provision of funding and equipment and training ...
Also not saying the US rhino science community should not be involved going forward as I really, really, really DO feel the International Rhino Foundation is doing a fantastic job in providing critical financial and other resources to the Indonesian Sumatran rhino conservation program (YABI).
I just with fingers crossed hope the Sumatran rhino can make that historic come-back even now where the population is only 80 individuals strong over 2 huge island landscapes.....