Great Mercury Island
Also known as: Ahuahu
Best time to dive
October to May
What you might see
- Moray eelLikely
Sightings are seasonal probabilities, not promises - even in peak season nature does its own thing.
Certification & difficulty
Advanced Open Water - advanced conditions (currents/depth); dive within your training.
Snorkelling
Snorkel-friendly - Possible in sheltered bays (e.g. Coralie Bay) in calm weather; not a dedicated snorkel-trail site
Safety notes
Surge near Great Mercury Island's corners (e.g. at The Bookcase), strong currents at Never Fail Rock/Whale Rock/Richards Rock, conditions vary a lot by bay so check forecast and choose site accordingly
Permits & fees
No marine reserve - standard NZ recreational fishing rules/bag limits apply; Great Mercury Island (Ahuahu) is largely privately owned farmland with some public/DOC land - respect landing restrictions ashore
Permits and operators change - confirm before booking.
Location
Nearest hub: Whitianga
This profile is desk research, compiled from public sources - not a first-hand dive report. Coordinates are approximate.