Izu Ōshima · Japan · Reef · Channel & pass
Keikai
Lava channels beneath a seasonal sunrise hammerhead route
Keikai is an Izu Oshima shore dive through a maze of lava channels, reaching 20 m. Soft corals cover the channel walls, and sunrise dives from mid-June to mid-October bring schools of hammerhead sharks; green turtles also appear here.
Also known as ケイカイ, Keikai Beach.
Where it is and how deep
No published position for this site — the map shows Izu Ōshima and its other sites; operators know the mooring.
The dive
From the beach, the dive follows interlocking channels cut through the lava terrain. Their walls carry soft corals, with nudibranchs, seahorses and blennies among the smaller animals to look for. Green turtles share the site, alongside seasonal hammerhead schools at sunrise.
Marine life and season
- Hammerheads
- Sea turtles
- Nudibranchs
- Macro critters
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Good | Good | Good | Good | Good | Good | Prime | Prime | Prime | Prime | Good | Good |
Season follows Izu Ōshima: Hammerhead schools pass at sunrise from mid-June to mid-October.
Dive videos
Diving with Hammerhead Sharks on Oshima Island · gksurf on YouTube
Questions divers ask
When do hammerhead schools pass Keikai?+
Hammerhead schools pass at sunrise from mid-June to mid-October. Green turtles are also seen at the site.
Sources
- Izu Oshima fun-diving points — Yellow Dive
- Izu Oshima diving-point guide — Sea Sound
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