I don't like it either, but I think it would be worse if they turned away a macaw that needed a home, even if it doen't contribute to conservation. If the zoo is breeding them however...
I like hybrid Macaws!! The Green-winged x Scarlet Macaws at the Welsh Mountain Zoo are my favourite individual Parrots in any UK zoo (actually I've never set foot abroad so...) and I have two adoptions of them in memory of my parents. As my interest is in display rather than conservation I am happy with hybrids. This particular bird, called "Olive", does not belong to the zoo itself, but to the company that provides the bird and Sealion shows (excellent they are too). The bird show features another hybrid Macaw, "Reuben", who flies to a volunteer member of the audience to collect a donation for the Hawk and Owl Trust.
The show I attend is always the one o'clock one, so I can speak only for that as I think some different species appear in other shows. Apart from the Macaws (there are several other than the hybrids) there are Harris Hawks, African Pied Cows (I posted a photo yesterday), Barn Owls, a European Eagle Owl, a Northern Ground Hornbill (it came from Exmoor Zoo), oh last year there was a Trumpeter Hornbill (see photo), and there's "Derek" the Hooded Vulture (another photo). There used to be a Crested/Red-legged Seriema called "Jose", but I haven't seen him for a while - he could always be in a later show. There have been a number of other Parrot species too over the last few years. At one time it was the "Parrot Show", but diversified when the new theatre opened.
Hybrids between Ara species such as the specimen in the photograph and the ones at the Welsh Mountain Zoo are fertile. I have just done a little more research and found that Ara x Anodorhynchus hybrids are infertile, those between mini Macaw species are fertile and it is probable that even mini Macaw x Aratinga Conures hybrids are fertile too.
Yeah most South American psitticines of a similar size produce fertile offspring, they are all very closely related and it is thought probably all the result of fairly recent adaptive radiation.
