Myanmar · Andaman Sea

Mergui Archipelago

Best liveaboard season aligns with dry weather and calmer Andaman crossings.

The Mergui (Myeik) Archipelago is 800 islands in the Andaman Sea off southern Myanmar — barely explored, accessed only by liveaboard from Thailand, with reef shark aggregations, manta rays, and the occasional whale shark. The marine park feels untouched because it largely is.

Good season

Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

October–May only. February–April is peak for visibility and pelagics.

Trip duration

6–8 night liveaboard from Ranong or Kawthaung.

Dive style

Wall and pinnacle drifts; some current.

Dive level

Advanced + 50 dives recommended.

Reef health

What you’ll actually find
Mixed

Some loss since the 2010s, but the reef still has plenty to dive. Pick depth and shoulder-season carefully.

Coral reef health

How is this calculated?
A decade ago
Survey 2014
39%
Today
Survey 2024
36%

On current trend, no live coral by ~2144. Losing about 0.3% cover per year — roughly 120 years of reef left to see if nothing changes.

Heat stress right now

Watch

Mild warmth. Worth watching — no bleaching yet.

NOAA Coral Reef Watch · updated May 2026 · 10.1 °C-week heat dose

What to expect on a dive

Remote, lightly dived. Cover holds up better than at the more-trafficked sites further south.

Sources, methodology, and the raw numbers

Raw observed numbers

  • Coral cover: 36% (survey Sep 2024, GCRMN / DMCR Andaman Sea transect)
  • Bleached: 9%
  • Recent mortality: 3%
  • Andaman Sea — observed condition reflects the slow loss regional pattern.

Raw thermal numbers

  • NOAA CRW alert level: Watch
  • Degree Heating Weeks: 10.1 °C-wk
  • SST anomaly: +0.6 °C

How we summarise this

Observed coral cover, bleaching, and mortality come from named in-situ surveys with a stated date and method — they describe one snapshot of one reef and do not extrapolate to neighbouring sites. Current thermal stress is satellite-derived from NOAA Coral Reef Watch at ~5 km resolution; it indicates risk, not observed coral damage. We deliberately separate observed condition, current thermal stress, and projection — and we never publish a projection without a documented model and uncertainty.

Sources

Reef condition changes year to year. If you visit, consider supporting responsible-travel and conservation operators on the ground.

Pressure on this reef

Protection · fishing · what you can do

Protected-area status

Multi-use MPA

Inside a designated MPA that permits regulated fishing and other uses. Worth checking which zones at this location are no-take.

Fishing pressure

Moderate fishing pressure

Dominant pressures

  • industrial fishing
  • limited monitoring

1 Green Fins-verified operator known at this location.

What you can do

Myanmar reefs face limited monitoring and permit-heavy access. Remote Red Sea zones (Sudan, Saudi, Eritrea) have less enforcement infrastructure. Picking liveaboards that participate in reef research helps fund data collection.

Protection status sourced from Protected Planet / WDPA and refined with Marine Protection Atlas. Fishing pressure proxy is Global Fishing Watch AIS data. See the methodology for what these sources can and can’t prove.

Dive sites here

0 curated

Dive sites for this location are still being curated.

We’re working through our top destinations first. Check back soon, or browse the globe for areas with sites already mapped.

Gear

What to bring

Basic kit

What divers say

We didn't see another dive boat for six days. That alone is becoming impossible elsewhere.
Trip report