Stewart Island - Mergui Archipelago

Stewart Island, or Ba Wei, sits just northwest of Cavern Island and it’s one of those spots that really delivers on its name: a massive hole punched clean through a smaller islet off its southern tip. You can grab some seriously dramatic topside photos before you even hit the water. Drop down the steep walls on either side of that islet and you’ll find a network of big swim-throughs. We’ve drifted through them with schools of snapper and fusiliers so thick they almost block out the light. It's a fun dive, especially for photographers and those who enjoy a bit of cave exploration without the full commitment of a true cavern dive. Just keep an eye on the current when you’re planning your entry and exit.

Location
Mergui Archipelago, Myanmar, Southeast Asia
Coordinates
10.300000, 98.050000

Best Time to Dive in Mergui Archipelago

The warmest water temperatures in Mergui Archipelago occur in May, averaging 30.8°C. The coolest conditions are in January at 28.5°C.

Monthly Water Temperatures

  • January: 28.5°C
  • February: 28.9°C
  • March: 29.6°C
  • April: 30.7°C
  • May: 30.8°C
  • June: 29.9°C
  • July: 29.5°C
  • August: 29.2°C
  • September: 28.9°C
  • October: 29.0°C
  • November: 29.2°C
  • December: 28.7°C

Nearby Dive Sites in Mergui Archipelago

Nearest Dive Centres to Stewart Island

Marine Life in Mergui Archipelago

Home to 173 recorded species including 106 reef fish, 49 hard corals, 8 seagrass & algae, 3 sharks & rays, 2 other, 2 octopus & squid.

Notable Species

Recommended Packing List for Stewart Island

Based on average water temperature of 29.4°C, currents 7 cm/s.

  • Shorty or Rashguard - warm 29°C water needs minimal exposure protection
  • Mask - essential for every dive
  • Fins
  • BCD - buoyancy compensator
  • Regulator - your most safety-critical piece of gear
  • Dive Computer - tracks depth, time, and NDL
  • Surface Marker Buoy (SMB) - essential for boat pickups
  • Dive Torch - useful for crevices and colour at depth
  • Underwater Camera - capture your diving memories