Oh-ruri-shijimi Season Arrives [Alps Azumino National Government Park, Horigane/Hotaka District]

The Oh-ruri-shijimi (Japanese large blue-like butterfly) began appearing on May 8, 2026, at the Horigane/Hotaka District of Alps Azumino National Government Park in Azumino City, Nagano Prefecture. As of May 19, 2026, at least six butterflies have been confirmed.

The Oh-ruri-shijimi is a large butterfly with azure-colored wings. It is an endangered species classified on the Ministry of the Environment's Red List as Category IA, and was designated as a natural monument of Azumino City in March 2022. Currently, its habitat is confirmed only in certain parts of Nagano Prefecture and the Aso region of Kyushu. Within the park, they can be observed in areas such as around the ponds in the Rural Culture Zone. (Collecting the Oh-ruri-shijimi is strictly prohibited.)

As they are rare butterflies, the park is engaged in public awareness activities, including observation tours of the emerged adults and survey events to count eggs and larvae.

Oh-ruri-shijimi Observation Tour

- Date: Saturday, May 23, 2026 - Time: 10:00 AM – 12:00 PM - Location: Around the pond (Meeting point: Guide Center Plaza) - Fee: Free - Capacity: 20 people (advance application required via the park's website) - Cooperation: Azumino Oh-ruri-shijimi Conservation Measures Council - Instructor: Mr. Nobuyoshi Nakata, former director of the Tabuchi Yukio Memorial Hall

Join the Oh-ruri-shijimi Survey!

- Date: Saturday, May 30, 2026 - Time: 10:00 AM – 12:00 PM - Location: Horigane Gate Building (Meeting point) - Fee: Free - Capacity: 20 people (for elementary school students and above; advance application required via the park's website) - Cooperation: Azumino Oh-ruri-shijimi Conservation Measures Council

It is expected that the Oh-ruri-shijimi can be observed until around the end of May. Please come to the park to see this rare butterfly.