Fantastic Fireflies You Can’t Miss Summer in Japan | Guidable - Your Guide to a Sustainable, Wellbeing-centred Life in Japan

Fantastic Fireflies You Can’t Miss Summer in Japan

By Yae Jun 8, 2018


Have you ever seen fireflies in your life?
If you are not a fan of bugs, you may never want to see fireflies. However, it is good to know the unique and attractive points that only fireflies have.

Here in Japan, you can enjoy watching the beautiful illumination that fireflies create early in summer. Rainy season (May to June) is the best time to see the fireflies. Let’s see what kind of miracles you can find from fireflies in this article.

There are many advantages of the rainy season in Japan and enjoy watching the fireflies glowing is one of them you can’t miss.


1. The Best Condition for Fireflies Watching

Some conditions are required for fireflies to come outside. Some of them are:

・Warm and humid weather with no winds
・No rain (the dry hours during the rainy days)
・Cloudy day with no moonlight

Fireflies are delicate bugs. They like to choose the best condition for showing us some beautiful illumination. Generally, fireflies appear and glow for about 3 times in a day: from 19:00 to 21:00 for the first time; around 23:00 for the second time; and 2:00 in the morning for the last time.

Anyway, the best hour for watching fireflies is from 20:00 to 21:00.


2. Types of Fireflies You Can Find in Japan

There are 40 types of fireflies that you can find in Japan. Out of these, there are 3 major popular ones:

・Luciola cruciate (Genji Botaru)
・Luciola lateralis (Heike Botaru)
・Luciola parvula (Hime Botaru)

Not all of the above fireflies can glow. Only Genji Botaru and Heike Botaru can. Genji Botaru’s lighting is exceptionally strong.


3. Knowing More about Fireflies

Do you know why fireflies glow? Fireflies use their own lighting for communication. That means they are talking to each other by glowing. If you pay attention to fireflies near a river, you’ll see that they are blinking. This is a sign to let other fireflies know where they are.
By the way, did you know that only male fireflies can fly?

Glowing is also a tool of communication for threatening enemies, warning other fireflies about some danger, and attracting a partner.

Usually, fireflies have a short life. Male fireflies can live for about 5 days, and female fireflies can live for nearly a week.

That’s one of the reasons why it is a valuable experience to watch the fireflies during their short summer.


4. How to Behave when Watching Fireflies

Since fireflies are delicate bugs, there are some rules for protecting them while firefly watching.

・Do not shine the fireflies by using flashlights.
・Do not take pictures with flash.
・Do not leave trash in or close to the river. Keep the area clean.
・Do not take fireflies with you back to your home.

If you shine the fireflies or use any lights on, fireflies get surprised and they would hide somewhere or stop glowing. Fireflies need darkness, and if you are visiting their territory, you must respect that.


5. Places for Enjoying Watching Fireflies around Tokyo

For those who are busy and can’t take few days off to fly somewhere far in Japan, don’t worry. You also have the chance to see the real fireflies close to Tokyo.


1. Amusement Park Yomiuri Land @Tokyo

4015-1, Yanokuchi, Inagi, Tokyo, 206-0812

<Best time to go>
From June 1st to July 1st (only Friday, Saturday and Sunday in this term)

<Best hours>

500 yen



2. Roman no Mori Kyowakoku @Chiba

659-1, Toyofusa, Kimitsu city, Chiba, 292-1179

<Best time to go>
From May 26th to July 1st

<Best hours>

500 yen

Here you can enjoy outdoor activities and hot springs as well. There are hotels close by where you can stay, have dinner and enjoy a bath at a hot spring.

Many people love decorative illumination. You will be amazed of how beautiful is the natural lighting that fireflies create by themselves, without using any electricity.
Fireflies don’t harm people so no need to run away from them.

I hope you will enjoy the summer illumination made by fireflies.
You may even forget the annoying humidity of rainy days in Japan.