Similan Islands, the area around Snapper Alley

Similan Islands · Thailand · Reef · Coral garden

Snapper Alley

Huge schools of snapper over large hard-coral tables

Area photo: KOSIN SUKHUM · CC BY-SA 4.0

Snapper Alley is southeast of Koh Bangu, the island numbered 9 at the north end of the chain, and is one of the easiest dives in the park: healthy hard coral with large coral tables, normally no current, and the diving done inside the top 10 m. It is known for the huge schools of snapper that hold over the coral, and there are swim-throughs along the way.

Where it is and how deep

Depth profile of Snapper Alley: typical dive 0–10 m (0–33 ft), deepest point 21 m (70 ft) 18 m · Open Water30 m · Advanced40 m · Recreational limit0 m10 m21 m maxtypical dive
Depths on a shared scale to 40 m (130 ft); dashed lines mark common certification limits.

8.6733° N, 97.6525° EApproximate position — the dashed circle shows where the site lies; your operator's briefing has the mooring.

The dive

The diving is done in the top 10 m with the sea bottom around 21 m below, so the profile is set by where the coral is rather than by a limit, and with no current normally running the route can be chosen freely and changed halfway through. Large tables of hard coral make up most of the ground, with swim-throughs to pass between them, and the shallow water leaves a wide margin on gas and time.

The snapper are the fixture of the dive: they school over the coral in numbers and are what the site is known for. Around them the site records barracuda, giant trevally, surgeonfish and triggerfish, with whitetip and blacktip sharks, manta rays and even whale sharks on the list of what has been seen here rather than what any one dive should be expected to deliver.

Marine life and season

  • Reef fish swarms
  • Barracuda
  • Trevally & jacks
  • Manta rays
  • Reef sharks
  • Whale sharks
Month-by-month season rating for Snapper Alley
JanFebMarAprMayJunJulAugSepOctNovDec
PrimePrimePrimeGoodOff-seasonOff-seasonOff-seasonOff-seasonOff-seasonOff-seasonGoodPrime

Season follows Similan Islands: Similan National Park closes mid-May to mid-October for monsoon recovery; calm seas and peak manta/whale shark sightings run December-March.

Sources

  1. Snapper Alley — Divezone
  2. Snapper Alley — Scubago

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