Hole in the Rock — Motukokako
Bay of Islands · New Zealand
Motukokako (Piercy Island) at the entrance to the Bay of Islands is pierced by a natural rock arch that boats navigate at high tide. Below the surface, the island's base is a terrain of boulder fields, swim-throughs, and short wall sections alive with blue-throated wrasse, marblefish, and banded dottyback. Bottlenose dolphins regularly rest in the sheltered north-facing bay and occasionally interact with divers.
Conditions
Depth
5 to 25 m
Open water and up
Current
Often strong
Can pick up on the edge
Visibility
8 to 14 m
Clearest in the calm season
Water
15 to 22°C
7mm wetsuit
Month by month
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Water (°C) | 20 | 20 | 19 | 18 | 17 | 16 | 15 | 15 | 15 | 16 | 17 | 19 |
| Vis (m) | 10 | 12 | 12 | 12 | 10 | 8 | 8 | 8 | 8 | 10 | 10 | 10 |
| Current | Moderate | Gentle | Gentle | Still | Still | Moderate | Strong | Strong | Moderate | Moderate | Gentle | Moderate |
Your chances of seeing each animal
Jewel Anemone
Last confirmed Feb 23, 2026 · 20 records
Very likely
Most dives
New Zealand Snapper
Last confirmed May 27, 2026 · 39 records
Very likely
Most dives
Sea Urchin
Last confirmed May 27, 2026 · 16 records
Very likely
Most dives
Marblefish
Last confirmed May 11, 2025 · 6 records
Very likely
Most dives
Spotty
Last confirmed Jan 17, 2026 · 5 records
Very likely
Most dives
Bottlenose Dolphin
Last confirmed Apr 5, 2026 · 25 records
Likely
About 6 in 10 dives
Blue-throated Wrasse
Last confirmed Mar 18, 2025 · 1 records
Likely
About 6 in 10 dives
Yellow Zoanthid
Expected
Known here, not yet in recent logs
Gear