Iriomote & the Yonara Channel · Japan · Pinnacle · Pelagic & blue water
Ogan
The Eastern Root, huge hidden roots rising from the seafloor
Ogan, also called Nakanokami Island, is an uninhabited island about 15 km southwest of the southern end of Iriomote. It is the hardest dive around Iriomote, swept by a fast current, and divers make the trip for a very high encounter rate with manta rays, dogtooth tuna and barracuda.
Also known as Nakanokami Island, Nakano Kamishima, Nakanomikami Island.
Where it is and how deep
24.1946° N, 123.5635° EApproximate position — the dashed circle shows where the site lies; your operator's briefing has the mooring.
The dive
The best-known part of Ogan is the Eastern Root, a dynamic terrain of huge hidden roots rising from the seafloor at 40 m. The current here is fast, and big fish turn up at a very high rate: manta rays, dogtooth tuna and barracuda.
Marine life and season
- Manta rays
- Tuna
- Barracuda
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Prime | Prime | Prime | Prime | Good | Fair | Fair | Fair | Fair | Good | Prime | Prime |
Season follows Iriomote & the Yonara Channel: Manta odds are highest from November to May; mid-June to October is the sunniest stretch, but it overlaps the June to September typhoon season.
Know before you go
- Strong currents and down-currents tend to occur at Ogan, so care must be taken throughout the dive.
Dive videos
Ogan · Nisepinoko on YouTube
Questions divers ask
How long is the boat ride to Ogan from Iriomote?+
About 1 hour by boat. Ogan is an advanced dive because of its fast current and down-currents.
Sources
- Yonara Channel (nearby sites: Ogan) - ScubaGo — ScubaGo
- Iriomote diving accident risks — iriomote-tour.com
- Iriomote diving spots — iriomote-tour.com
- 仲の神島 - OpenStreetMap — OpenStreetMap
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Manta rays at several points along a constant-current strait
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