Shark's Hole Tikehau: Deep Wall and Grey Reef Shark Aggregations

Shark's Hole is defined by a dramatic, steep outer-reef drop-off that begins at approximately 15 to 20 metres. As you descend, the reef wall transitions into a vertical descent that leads directly into deep, blue water. The site is located on the outer reef, south of the Tuheiava Pass, where the ocean conditions are more exposed than the sheltered lagoon dives. This positioning ensures a direct encounter with the deep-water currents that drive the local ecology.

The defining feature of this site is a narrow, vertical fault or chimney located at the bottom of the drop-off. This geological feature reaches depths of 50 to 55 metres and creates a complex underwater landscape. Within this vertical gorge, you will find small caves, crevices, and ledges that provide structure to the reef face. An archway links the two sides of the gorge, creating a natural passage through the reef wall.

This site is a primary location for observing large aggregations of grey reef sharks (Carcharhinus amblyrhynchos). Depending on the daily current and ocean conditions, these sharks may hold at recreational depths near the hole or stay much deeper. On many dives, you can see schools numbering into the hundreds. They are often joined by whitetip reef sharks (Triaenophthalmus dhaabas) and blacktip reef sharks (Carcharhinus melanopterus) navigating the wall.

The verticality of the terrain creates a distinct layering of marine life. Along the upper sections of the wall and the initial drop-off, the reef is heavily carpeted with squirrelfish and other reef fish. As you move deeper toward the chimney, the fauna shifts toward larger pelagic species. You may encounter barracuda, dogtooth tuna, and various species of snapper moving along the blue water edge.

Visibility at Shark's Hole is typically consistent, ranging between 30 and 40 metres. This clarity is essential for observing the movement of sharks within the vertical fault and for spotting tuna patrolling the edge of the reef. The sheer scale of the drop-off combined with the visibility allows for a clear view of the abyss beyond the recreational depth limits. The site is significantly more topographically complex than the shallower reef and pass sites found nearby.

Conditions at the site are heavily influenced by the daily currents and the specific position of the hole. While the current can vary, it is the main driver for shark behavior and aggregation density. Understanding the relationship between current flow and shark presence is key to finding the most active part of the site. Most sightings occur where the current brings nutrients toward the vertical faces of the reef structure.