Suo-Oshima: One of the World’s Largest Areas of Alveopora Japonica Coral!!

While the Seto Inland Sea area is home to around 3000 islands of various sizes, the third largest, Suo-Oshima, is known affectionately as the “Hawaii of Setouchi”.

Did you know that in recent years, one of the world’s largest areas of Alveopora japonica coral was found in the sea to the southeast of the island?

A little later, in February 2013, it was designated as the Seto Inland Sea’s first marine park due to its wonderful underwater scenery and wide variety of creatures!

It is found near Okikamuro Island, which we introduced in the Shark Jizo article [https://setouchifinder.com/en/detail/349]. However, even if you look at the sea from the shore, you can’t see the Alveopora japonica.


On the other hand, this is the world that spreads out below the surface!

Those who wish to see the real deal up close, we recommend heading to Nagisa Aquarium, which is located 15-minutes drive away.


At the aquarium, they are conducting research on the Alveopora japonica coral.

You can even see baby coral.

There is a little bit of a prequel to the story: Local fishermen noticed the existence of the coral around 10 years ago, but not realizing it was Alveopora japonica coral, just let it be thinking it was some kind of strange seaweed.

Over those 10 years, it has grown to be one of the world’s largest. If they had realized that it was coral when they discovered it, I wonder if the area would have become big enough to be designated as a marine park?  Thinking about this, the feeling of gratitude towards the fishermen just wells up.

Currently, in addition to monitoring tours held by a local NPO, the administration is launching initiatives aimed at building a visitor center.

These Alveopora japonica stamps were issued in commemoration of the Marine Park, and were so popular that they sold out in an instant.


We can’t wait to see what happens in the future.

Oidemase! Come to Yamaguchi
Jikamuro Marine Park

One of world’s largest Alveopora japonica coral growth areas, in February 2013, it was given the name Jikamuro Marine Park, and is a special reserve within Setonaikai National Park.

Address: Jikamuro, Suo-Oshima-cho, Oshima district, Yamaguchi prefecture
HP: awasango.web.fc2.com (Japanese)

Nagisa Aquarium

An aquarium where you can observe Alveora japonica coral, sea anemone (Halcurias carlgreni) among other fauna growing in and around Suo-Oshima. Although it’s small, it has one of Japan’s widest touching pools.

Address: 2211-3 Ihota, Suo-Oshima-cho, Oshima district, Yamaguchi prefecture
Admission: Adults JPY210, Elementary & Middle school students JPY100
Open: 9:00~16:30
Closed: Dec.30th ~ Jan. 2nd
HP: nagisapark.jimdo.com (Japanese)

The photographs of Alveora japonica used in this article are from NPO organization “Shizen to tsuri no network” that carries out activities related to studying and protecting the coral.

Setouchi Finder Photo-writer: Masashi Fujimoto


Show larger map>

Give us your Like


Written by

Masafumi Fujimoto

Masafumi Fujimoto

Masafumi Fujimoto Hi there! My name is Masafumi Fujimoto. Until the Great East Japan Earthquake of 2011, I was engaged in editing production at an advertising company in Tokyo. However, the earthquake was a turning point in my life and I headed home to Yamaguchi. When I arrived, I was extremely energized and motivated to help revitalize the region, but I had a hard time adjusting to the motivation level of the local people. Around that time I met an elderly lady who said: "It doesn't matter if all the people move away from the island; that's just the nature of things. Someday people will come back again." Lessening the tension I’d been feeling, those few words relieved me hugely, and I was able to finally adjust. Since then, I've been involved in writing and editing magazines, and working in advertisement production, as well as doing a little bit of farming. I also spend time walking around Setouchi searching for the many, many voices out there.


Trendy keywords

See more articles about "Others"







Trendy keywords

Area Search