Yes I am not sure how you deal with the best interests of two or more adult males but your suggestion to pension out the oldies is probably the best so far. Not a particularly natural state of affairs but then again zoos are not natural and we can only do what seems best. Pensioning the oldies is better than withdrawing a virile male as long as more offspring is what you really want. The plight of mature breeding males is a cross species, ongoing issue for all zoos. I guess I failed to articulate that the realisation hit me that Rigo is back not to breed but to keep people like me happy. I am 50 and have vivid memories of a not so happy Rigo and heartbreaking glimpses of him isolated, but close enough to hear and smell, in the adjoining primate pits for too many years. Is it possible that this is a combined PR and population control decision?