I visited Wingham a few weeks ago and spent some time watching their gibbons. Does anybody know which collection they came from? Are they naturally occurring hybrids or are they Mullers x Agile gibbons that were produced by their parents being mixed in captivity somewhere?
Does anybody have access to the gibbon stud book then? I can't find a copy online. Obviously - hybrid animals are usually not something you would want in a collection, but this is an example of a naturally occurrng hybrid.
The 'naturally-occurring' hybrid is between Müller's and White-bearded Gibbon (Hylobates albibarbis), which is now usually separated from the Agile Gibbon.
Wingham have got a lot of their primates through Stichting AAP. My guess is these gibbons are from there (so be from anywhere around the world).
I don't know if this helps but its a picture of the label for the gibbons at the park http://www.zoochat.com/1283/gibbon-sign-164989/
