Common health problem (and can be fatal) in captive orangutans is bacterial aerosaculitis (of the larynx ventricles and sacs), pneumonia and pharyngitis, resulting also of too much time spent on the ground ''playing'' with faeces or even coprophagia, and feeding from the ground. Just to note.
Elmer has now had 13 Off-spring; 6 of which are still surviving and only 3 of which in a breeding situation. I doubt that they want to breed anymore with Elmer due to his children reproducing so well. An example of this is Dahi at Madrid who already has 5 off-spring