Snorkelling in Mauritius: The Best Spots and When to Go

Almost the whole island is surrounded by a barrier reef a kilometre or two offshore. Inside it the water is shallow, warm and flat, with sand bottoms and scattered coral heads; outside it the ocean drops away. That reef is the reason you can swim in near-still water in a place that faces the open Indian Ocean, and it is also where the fish live. Snorkelling in Mauritius is therefore a matter of getting to the reef, and the reef is a boat ride away.

Visibility inside the lagoon is usually ten to twenty metres on a calm morning, the water sits between 24 and 29 degrees through the year, and there is nothing in it that wants to hurt you beyond the coral itself, which cuts if you stand on it. Children, nervous swimmers and people who have never worn a mask do well here, which is why we have had three generations of the same families snorkel with us.

The east coast: Trou d'Eau Douce and Île aux Cerfs

This is our water. The east coast holds the largest lagoon in Mauritius, and the reef that protects it runs past Île aux Cerfs and the small islands south of it. The spot we have used since 1995 sits where the lagoon shelves towards the reef: two to five metres deep, protected from the swell, with coral heads full of parrotfish, butterflyfish, trumpetfish and the occasional lionfish holding still under a ledge. Green and hawksbill turtles graze the seagrass nearby and we see them on roughly eight trips out of ten.

Our catamaran cruises stop here, usually at about eleven, after the GRSE waterfall and before lunch, and the private boats can too. Gear is on board and the crew goes in with you. It is a working reef, not a marine park, and the fish behave accordingly: unbothered, close, and plentiful.

Blue Bay Marine Park, south-east

Blue Bay, near the airport, is the island's protected marine park and the place most guidebooks name first. The coral is in good condition, the water is very clear and glass-bottom boats run from the beach. It is also popular, so the best of it is early in the morning. If you are staying in the south or combining it with a flight day, it is well worth a couple of hours.

The north and north-west: Trou aux Biches, Pointe aux Piments and Coin de Mire

The north-west coast has gentle beach snorkelling at Trou aux Biches and Pointe aux Piments, with turtles seen regularly close to shore. From Grand Baie, boat trips head out to Coin de Mire and the northern islets, where the water is deeper and the visibility often the best on the island. These are longer days with more open water and suit confident swimmers.

The west and south-west: Flic en Flac, Tamarin and Le Morne

Flic en Flac has a long, accessible reef that is also the island's main diving coast, and Tamarin Bay is where early-morning dolphin trips leave from. Further south, the lagoon off Le Morne and Île aux Bénitiers is shallow, scenic and sheltered. Afternoons on the west coast are often calmer than on the east, which matters if you can only go late in the day.

Belle Mare and the east coast beaches

North of Trou d'Eau Douce, the Belle Mare and Palmar stretch has beach snorkelling over sand and seagrass. It is pleasant for a swim with a mask but thin on coral; for the proper reef, you still want a boat.

• Parrotfish in half a dozen colours, grinding the coral loudly enough to hear underwater
• Butterflyfish and angelfish in pairs over the coral heads
• Trumpetfish hanging vertically among the branching coral
• Clownfish guarding their anemones in the shallows
• Moray eels, usually just a head in a hole
• Green and hawksbill sea turtles over the seagrass; they are wild, so sightings vary with their mood
• Octopus, if you are patient and look at the rubble rather than the fish
• Lionfish and the occasional stonefish, which is the one reason not to stand on anything you cannot see

Beach snorkelling in Mauritius is easy and free, and in a few places (Blue Bay, Trou aux Biches) genuinely good. But the lagoon floor near most beaches is sand and seagrass; the coral and the fish concentrate at the reef, and the reef is a long swim out. A boat drops you on top of it, rested, with a ladder to climb back up and someone watching the water. For first-timers and families that is not a luxury, it is the difference between a nice swim and the thing you talk about for years.

On our catamaran days the snorkelling stop is one chapter of a full day: the waterfall first, the reef at mid-morning, lunch, then Île aux Cerfs. Masks, snorkels and fins are on board, and the 5 Island Tour adds a swim and apéro stop at a second site.

• Use reef-safe sunscreen and put it on well before you get in; better still, wear a rash vest and let it do the work
• Never stand on, hold or kick the coral. If you need a rest, float, or swim to sand
• Do not feed the fish; it changes their behaviour and the reef's balance
• Keep a few metres from turtles and let them come to you; they will if you are still
• Defog your mask with a drop of soap or a spit and rinse, and clear your hair from the seal
• If you wear glasses, tell the crew: a mask with a reasonable fit matters more than a perfect prescription