Fakarava, French Polynesia tide times

Fakarava is a UNESCO Biosphere Reserve atoll in the central Tuamotus, 480 km northeast of Tahiti — elongated, 60 km long and 25 km wide, with two passes that are among the most powerful and biologically productive in French Polynesia. Garuae Pass in the north is the largest atoll pass in French Polynesia: 1.6 km wide and 15 m deep, it handles the majority of the atoll's tidal exchange with the Pacific. Tumakohua Pass (South Pass) in the south is 100 m wide and 16 m deep — narrower, faster, and internationally famous for a specific annual phenomenon.

Every June and July, the Tumakohua Pass becomes the site of one of the most documented predator aggregations in the Pacific. Coral grouper (Plectropomus leopardus) gather in the pass in their thousands for their annual spawning aggregation, drawn by the combination of full moon, the pass current, and the water temperature. The grouper spawn draws the predators: hundreds of grey reef sharks station on the pass walls in the outgoing current, stacked from 5 m to the sandy floor at 15 m, facing the current and feeding on the spawning mass. This is not hyperbole — underwater photographs from this event show wall-to-wall grey reef sharks in a density not documented anywhere else in French Polynesia. Divers float in the current above them watching the predation in real time. The aggregation peaks in the week around the full moon in June and continues for approximately three weeks; book Fakarava dive operators in March for a June dive.

Outside the grouper aggregation season, South Pass runs 3 to 6 knots on the spring ebb and still aggregates significant grey reef shark numbers (20 to 60 individuals is typical year-round), napoleon wrasse, eagle rays, and schooling barracuda and trevally. Garuae Pass in the north is the more accommodating intermediate dive: wider, slower, more light from above, and the 1.6 km width gives time to watch the lagoon ecosystem transition on either side of the pass. Pearl farm visits in the Fakarava lagoon interior are accessible by boat and the farm operators explain the temperature and tidal water quality management that makes pearl cultivation viable. Motu camping — sleeping on the small coral islets inside the reef — is available through some Fakarava operators; the starscape above a dark atoll motu is a specific experience worth planning around. Predictions on this page come from Open-Meteo Marine (gridded model, ±45 min / ±0.2–0.3 m). The Fakarava dive operators are based in Rotoava village on the north of the atoll and in the small settlement near South Pass. The north operators handle Garuae Pass; the south operators handle Tumakohua (South Pass). For the June grouper aggregation dive, booking 3 to 4 months ahead with the specific South Pass operators is essential — the event generates international demand and space is genuinely limited. The operators accept only certified divers with drift dive experience for the South Pass current dives. The Garuae Pass at the northern end of Fakarava is one of the Pacific's most celebrated drift dives, and its character changes completely with the tidal phase. On the outgoing ebb, hundreds of grey reef sharks and large grouper congregate at the pass entrance in a phenomenon known locally as la cascade — the cascade — as fish wait in the current break. On the incoming flood, the pass runs in the opposite direction and the fish disperse into the lagoon; both phases attract divers, but the ebb aggregation is the signature experience. Dive operators at Fakarava time two daily dives to hit the ebb at Garuae and the flood at the southern Tetamanu Pass, where a different mix of species characterises the southern entrance. The village of Rotoava at the northern end of the atoll is the operational base; the pass is a 20-minute boat ride from the village jetty. Night dives in the pass on new-moon neap tides, when current is minimal and bioluminescence is strongest, are offered seasonally.