Why do the fur seals have a trampoline suspended above their exhibit? Is it so they'll bounce back into the exhibit in case they try to leap out and escape? [I know that this probably isn't a trampoline, but it was too fun not to speculate on it being one to resist.]
1) it's for shade - though this would be more for the visitors to the underwater viewing window than the animals (maybe the lattice is because a solid shade panel would catch the wind too much?)