Asahiyama Zoo is a world pioneer of "behavioral exhibits." What are behavioral exhibits, and why did you decide to implement them?

Behavioral exhibits allow the animals to relax, which brings out their natural temperament and the activities that go along with that, and allow them to be seen by visitors through ingenious displays. In 1997, the lions and leopards were moved to a new cage, but since members of the cat family are nocturnal, they are sleeping during the daytime when visitors come to the zoo to see them. I felt that the traditional way of displaying them didn't allow them to be experienced doing their natural activities.

Because of that, I first decided to create a display that would show these sleeping beasts in an interesting way. The place that leopards can relax best is a high place. So I thought that if I could build a comfortable place for them, the leopards would surely choose that place to sleep. Then by looking up from below, visitors would be able to see parts that they had never seen before, such as their stomachs and the bottom of their feet. That's how I came to develop an animal display that was unlike traditional ones.

I also considered the distance from the animals. The recent trend in zoos around the world is to create environmental exhibits without a fence, but with a deep and wide trench putting a huge distance between animals and humans. From 10 meters away, a lion can roar all it wants, but it won't frighten the visitors, and therefore they don't react. For animals kept in captivity, there is nothing more agonizing than lack of stimulation. Even though environmental exhibits recreate their natural habitat, the lions aren't really going to go hunting. The environmental exhibit may become like a cell with a lack of stimulation for the animals living there.

We decided to accept the fact that zoos are man-made places, and that we would reduce the distance between humans and animals to an astonishing degree, which is the exact opposite of environmental exhibits. The lion cage was constructed to get them as close as possible while maintaining safety. When your eyes meet across the glass, those are truly close and confronting moments. When the lions roar, of course the visitors are surprised. And when humans have such frank reactions to their roars, the lions really sense it. Animals in captivity must have an environment where they can relax, but at our zoo the visitors are the "cat toys," which therefore helps the lions relax.

What sorts of things did you devise to get the animals to be more active?

To get the animals to act more animal-like, it's necessary to create an environment that allows them to naturally display things such as their traits, physical abilities and thought patterns. For example, in the penguin pool, besides adjusting the depth of the pool, we also added several obstacles such as a reef and an underwater tunnel that visitors can look up from. Penguins turn at sharp angles when they swim, so by having many obstacles in the water, they appear to be bouncing around while they swim. When they start chasing each other, their movements become really quite something. Since penguins are carnivorous, they instinctively watch things that move, so they are always looking at the people passing through the underwater tunnel, and sometimes their eyes meet. This is also an implementation of the idea of using humans as toys.

The key to our zoo's facilities is that they were built so that both humans and animals could see each other equally. The humans can see the animals from all different perspectives and places, and the animals also get to watch the humans. If you build an environment where the animals can act independently, then instead of viewing humans as a threat, they'll watch them with interest. As a result, they can live normal lives without feeling stress about being watched by humans. That's why behavioral exhibits are active exhibits.