Blue Bay tide times

Blue Bay Marine Park covers roughly 0.35 km² of coral reef on the southeastern coast of Mauritius, enclosed within the barrier reef in a bay that opens northeast. The coral coverage inside the park — hard and soft corals with over 50 recorded species — is among the densest in the Mascarene region, and the fish biomass within the protected boundary is substantially higher than the surrounding reefs. The park was gazetted in 2000 under the Fisheries and Marine Resources Act; entry requires a permit issued at the park office on the public beach.

The tidal regime is semidiurnal, with spring range 0.8–1.0 m following the Port Louis gauge. Neap range 0.3–0.5 m. The bay is enclosed by the outer reef and substantially protected from Indian Ocean swell; however, the southeastern exposure means that swell from the south and southeast, generated by the Roaring Forties, wraps through the reef passes during large Southern Ocean events. The lagoon depth inside Blue Bay ranges from 1 m over the reef flat at low water to 3–4 m in the channels; the deeper zones at mean water level are 2–4 m.

The tidal state is the primary determinant of snorkelling quality at Blue Bay. At high water (spring range 0.8–1.0 m), the reef flat is covered to 0.8–1.5 m and accessible across its full width; the corals are submerged and the fish communities are distributed across the whole reef rather than concentrated in the deeper channels. At low spring water, the shallowest sections of the reef flat — primarily the broad platform that runs across the western half of the park — can be as shallow as 0.1–0.3 m. Crossing this section at low water risks damaging the coral and injuring unprotected feet on the coral surface. The Marine Park Authority enforces a no-standing-on-coral rule; rangers operate glass-bottom boats within the park and observe.

Glass-bottom boat tours inside the marine park depart from the park's boat ramp on the public beach approximately every 30–45 minutes from 09:00 to 15:30. The standard tour covers the main coral garden in the western section of the park and a mooring area where snorkellers can enter the water. A park entry permit (fee at the gate, approximately MUR 200 per adult as of 2025) is required for all visitors, including glass-bottom boat passengers. Independent snorkelling from the beach directly into the park is permitted but requires the permit.

Blue Bay public beach sits adjacent to the marine park, 400 m of white sand facing the lagoon with casuarina shade trees. The beach is managed by the local district council (Savanne district). Sir Seewoosagur Ramgoolam International Airport is 8 km northwest; aircraft on final approach to runway 14 pass low over the southern lagoon on a track that crosses the park boundary at roughly 300 m altitude. Aircraft noise at Blue Bay during peak hours (10:00–14:00 on heavy-traffic days) is a consistent feature. For beach-based photography from the Blue Bay side, aircraft can be incorporated into the frame — or avoided by timing shots between approach intervals.

For anglers, the marine park boundary enforces a complete fishing prohibition inside. Shore anglers fishing the open lagoon south of Blue Bay, outside the park boundary, work the channels through the southern reef for barracuda and trevally on the early morning ebb. The low-water period exposes the reef flat and concentrates fish in the remaining water-filled channels — the 90-minute window from two hours before low water through the lowest point has the most concentrated fish activity in the channels.

Snorkellers based at the public beach should enter and exit through the clearly marked park entry point rather than walking across the reef flat in search of deeper water. The sandy entry channel from the beach to the deeper coral zone is indicated by buoys; following it at any tidal state avoids both coral damage and the ankle injuries that result from stepping on submerged coral at low water.

Predictions for Blue Bay on this page come from Open-Meteo Marine, a gridded global ocean model; accuracy is typically ±45 minutes on timing and ±0.2–0.3 m on height.