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

Frequently Asked Questions

What are the typical diving depths around Stewart Island?
Based on current information for Stewart Island, the typical diving depths are unknown. However, divers can expect to descend down steep walls on either side of the small island.
What kind of marine life and underwater environments can divers expect to see when diving Stewart Island?
Divers at Stewart Island can explore a vibrant reef environment featuring steep walls and numerous large swim-throughs. These swim-throughs are often filled with large schools of snappers and fusiliers, offering excellent photo opportunities. The smaller islet at the southern end also boasts a spectacular large hole, visible even above water.
How challenging is scuba diving around Stewart Island, and what level of experience is recommended?
Scuba diving around Stewart Island is rated as intermediate difficulty. This dive site is best suited for divers with an intermediate level of experience.
When is the best time of year to go scuba diving in Stewart Island for optimal conditions?
Information regarding the best time of year for optimal diving conditions at Stewart Island is not available in the provided data. For general guidance on dive seasons, please refer to our When to Dive section.
What scuba diving certifications are generally required or recommended for diving in Stewart Island?
The specific scuba diving certifications generally required or recommended for diving at Stewart Island are not detailed in the available information. Divers should always ensure they meet the necessary certification levels for intermediate dives.
What are the typical water temperatures, currents, and visibility like for diving around Stewart Island?
Details regarding the typical water temperatures, currents, and visibility for diving around Stewart Island are not provided in the current data. We recommend checking with local dive operators for the most up-to-date conditions.