Moor Hot Spring Firefly Viewing Event
Fireflies raised in the moor hot spring waters will perform a dance of light.

In the past, it was possible to see Heike fireflies around Tokachigawa Onsen.
However, as the town modernized, habitats suitable for fireflies dwindled, and after the summer of 1990 the Heike fireflies could no longer be seen.
The goal of restoring Heike fireflies at Tokachigawa Onsen is to bring back the early-summer scenes that were once common.

A distinctive feature of the firefly restoration is the use of hot spring water as the water source. Tokachigawa Onsen’s spring is a rare plant-rich moor hot spring.
Because it contains plant-derived components, it is rich in minerals essential for the proliferation of diatoms, which serve as food for pond snails.
This is the first successful example in Japan of restoring fireflies using 100% hot spring water.

Heike fireflies are distributed from Kyushu to Hokkaido, and into eastern Siberia and Korea, and they once thrived in wetlands and watersides surrounding rice paddies.
A characteristic of Hokkaido’s Heike fireflies is that their flashing intervals tend to be longer than those of Heike fireflies on Honshu.

Event period: Saturday, July 8 to Sunday, July 23
Event time: 8:00 PM–9:00 PM
Location: Tokachigaoka Park