1.there is a german zoo, perhaps leipzig whic does keep orangs in an outdoor environment with live trees...the orangs cannot use the trees as escape tools becaue of the width of the moat.
2. On perths-they do look unnatural. its ironic but they probably have the most active orang colony ive ever seen. the design of the climbing structures purposefully integrates loads of enrichment features, ranging from elevated feeder puzzles to bendy poles, ropes etc.
3. feedback has been reported as zoos move their orangs to new digs. many of the older animals, having lived their entire lives in stark, concrete cages, fail to fully adapt to the new, natural style outdoor enclosures, whilst others seem to fully adapt. i guess its like prisoners being released into the community
Quote 1. I don't know if its Leipzig. Paignton's have access to a complete grove of tall trees(willow and poplar?) the island being surrounded by a wide water moat. But you can see they hardly(if ever?)climb them- no tree damage, no nests etc.
Quote 2.- Perth- it all sounds a lot better than it looks from a photo, and with good enrichment too. I'll bet too they are very active because they're Sumatrans....( tho' I must say some of them weren't particularly active in the old style enclosures when I saw them some years ago as there was very little scope for them then.)
Quote 3. Yes, the problem is readjustment. At Paignton, two of the original females were middle/aged or old and had lived in regulation cages in the old Monkey House, and then in the Sobells at London Zoo. Bulu, the older one was even born there in 1961 and the other was very obese and could hardly get off the ground (she later died). Its the same as suddenly offering parrots which have lived in small cages all their lives, their freedom to fly, they can't do it. In Paignton's case, a group of young animals (or more active Sumatrans) might have quickly readjusted to these good surroundings and used them more.