@Prochilodus246 Unfortunately, this is a very common scene in Indonesian zoos. Even in a couple of the safari parks, which are mainly excellent establishments, there are birds of prey tethered to branches inside fake tree trunks. I was able to walk directly up to large birds such as Eurasian Eagle Owls and Crowned Eagles that were tied by their talons and my guess is that this Barn Owl in the Aquarium rarely has an opportunity to fly. Perhaps it's an injured specimen.
@Prochilodus246 Aside from maybe a off-display aviary after the aquarium's closing hours (Even then, its most likely to have a very small space), sadly no. Just like @snowleopard says, its a very common practise for Indonesian facilities to display their BoP like these, unfortunately. This owl are probably not injured, this is just how they exhibited it sadly.
