Similan Islands · Thailand · Reef · Pelagic & blue water
Koh Bon West Ridge
Soft-coral ridge where mantas pass overhead
Photo: Jean-Paul Boerekamps · CC0
Koh Bon West Ridge is a long, narrow ridge jutting out from the west side of Koh Bon, its rock covered in pastel-shaded soft corals. The reef is mostly rocky, but the marine life is good, and divers come above all for the manta rays that are often spotted over the ridge.
Also known as Koh Bon Ridge, Ko Bon West Ridge.
Where it is and how deep
8.8276° N, 97.7952° EApproximate position — the dashed circle shows where the site lies; your operator's briefing has the mooring.
The dive
The dive follows the ridge out from the west of the island as it falls away to depths of 35-40 m, the rock under a cover of pastel soft corals. Large schools of sweetlips or snappers often hang along it, and visibility typically runs between 20 and 30 m, so the ridge can be read from well above it.
Mantas are often spotted over the ridge or in the deep water to the south of it, and leopard sharks are common in the deeper water. The ridge is also a good place to look for the elusive purple fire goby, close to the rock among the soft corals.
Marine life and season
- Manta rays
- Reef fish swarms
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Prime | Prime | Prime | Prime | Fair | Off-season | Off-season | Off-season | Off-season | Fair | Good | Prime |
Season follows Similan Islands: The park is closed by law from mid-May to mid-October; December to April is the calm high season.
Photos from Koh Bon West Ridge
luluchouette · CC BY 4.0
Jean-Paul Boerekamps · CC0
Dive videos
SCUBA Diving at Koh Bon West Ridge · TTseScuba on YouTube
Questions divers ask
Are manta rays seen at Koh Bon West Ridge?+
Often. Mantas are spotted over the ridge itself or in the deep water to its south, and leopard sharks are common in the deeper water off the ridge.
Sources
- Koh Bon Island Dive Sites — Sunrise Divers Phuket
- Koh Bon, West Ridge — ScubaGo
- Koh Bon — Wetzone Divers
Photo credits
- A black-and-white striped sweetlips with yellow fins swims under a rocky overhang above a pale coral plate by Jean-Paul Boerekamps, CC0, via Wikimedia Commons
- A black-and-white banded sea snake winds across a sandy gap between rocks covered in red and grey growth by luluchouette, CC BY 4.0, via Wikimedia Commons
- Close view of a pale grey butterflyfish with a bright orange tail against orange and pink encrusted rock by Jean-Paul Boerekamps, CC0, via Wikimedia Commons
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