Modern zoo design increasingly uses naturalistic habitats that allow species-appropriate behaviors; welfare benefits over traditional exhibits are well documented.
Naturalistic zoo habitats that replicate key features of wild environments enable animals to perform species-appropriate behaviors including foraging, climbing, burrowing, and swimming. Animals in naturalistic habitats show lower stress hormones, higher activity diversity, and better reproductive success than those in barren enclosures. The ability to choose when to be visible to the public is a particularly powerful stress-reducer.