In the middle of Tokyo, there is a rich forest where rare animals such as raccoon dogs and kingfishers, endangered species, and even new species of plants have been discovered. The Emperor wished that it would be desirable to scientifically investigate and study the flora and fauna of the Imperial Palace, which is located in the city center but inhabited by many species.
The Imperial Palace is home to a variety of bird species. Survey by the National Museum of Nature and Science and others have confirmed around 50 species of birds a year.