On a June night, small lights flicker along a clear stream in Japan. This is Hotaru. Approximately 50 species of fireflies inhabit Japan, but the two that are most commonly observed are Genji Botaru and Heike Botaru. Genji fireflies have large bodies and emit strong light that flashes slowly. Heike fireflies are somewhat smaller and have weaker light, but they tend to be more numerous.
✨ 蛍が光る条件
Adult fireflies emit light for about two weeks. During this short period of time, they emit light to find a mate. The conditions under which fireflies fly actively are on cloudy nights with temperatures above 20 degrees Celsius, no wind, and little moonlight. The most visible time is after sunset, from 7:30 pm to 9:00 pm, and the light decreases at midnight.
In order for fireflies to live, they need clean water and underwater snails (a type of snail). The larvae eat fireflies to grow, so deteriorating water quality and decreasing the number of fireflies will directly lead to the extinction of fireflies. In Japan, during the period of high economic growth (1960s and 1970s), fireflies decreased dramatically in many areas, but now water quality improvement and conservation activities are being carried out in various places, and fireflies have returned to some places.
Firefly viewing spot
- Philosophy's Path (Tetsugaku no Michi), Kyoto:Genji fireflies fly in the canals along the walking path from Ginkaku-ji to Nanzen-ji. The best time to see them is from early to mid-June. It is a valuable place where you can see fireflies even though it is located in the city.
- Tatsuno-machi/Nagano Prefecture:Known as the ``Firefly Festival,'' thousands of fireflies fly around the Matsuo Gorge area. The best time to see it is from mid-June to late June, and it's about a 15-minute walk from JR Tatsuno Station. Some years, special trains run during the festival period.
- Shimizu district/Maibara City, Shiga Prefecture:It is known for the large number of flying fireflies that make you think of the Milky Way. This is the result of many years of conservation efforts by local residents. The best time to see them is from early to mid June.
- Kitakami City (Kitakami-shi)/Iwate Prefecture:Fireflies fly along the Kitakami River, and a firefly viewing event is held at Michinoku Folk Village. In the Tohoku region, fireflies appear later than other parts of Honshu, and the best time to see them is from late June to early July.
🌙 蛍狩りのマナーと準備
Watching fireflies is called ``Hotarugari'' (firefly hunting). Although it is called "hunting," you must not catch fireflies. Many viewing spots have rules such as "don't touch fireflies," "don't use flashlights," "don't take flash photography," and "watch quietly." Since artificial light interferes with the fireflies' luminescence behavior, it is recommended that you also reduce the brightness of your smartphone screen.
The basic clothing is long sleeves and long pants. Fireflies appear near water, where there are many insects such as mosquitoes and gnats, so you will also need insect repellent spray. It's safe to wear sneakers or waterproof shoes, as the footing can be dark and slippery.
The true beauty of fireflies cannot be seen unless you see them with the naked eye. The light is too small in photos and smartphone videos, making it difficult to recreate the impression seen in person. The experience of waiting quietly by the dark waterside on a June night and watching the lights emerge one by one is a way to spend early summer that can only be found in Japan.