Coral Reefs of the Maldives

Why Coral Reefs Matter

The entire Maldivian archipelago exists because of coral. Every island, every atoll, and every sandbank is built on a foundation of reef limestone deposited over millions of years. Today, living coral reefs continue to protect the islands from wave erosion, provide habitat for thousands of marine species, and support the livelihoods of Maldivian communities through fishing and tourism.

The Maldives is home to roughly 250 species of hard coral and 30 species of soft coral, making it one of the most coral-rich areas in the Indian Ocean. For visitors, the reefs offer some of the most spectacular snorkelling and diving experiences anywhere in the world.

Types of Reef in the Maldives

Understanding the different reef structures helps you know what to expect when you enter the water.

House Reefs

Most resort and inhabited islands are surrounded by a house reef, a fringing reef that drops off from the shallow lagoon into deeper water. House reefs are easily accessible from shore and are often the best place for casual snorkelling. You can expect to see tropical fish, sea turtles, and small reef sharks on a good house reef.

Atoll Rim Reefs

Each atoll is encircled by a barrier-like rim reef that separates the deep ocean from the inner lagoon. These outer reefs face strong currents and tend to support robust, wave-resistant coral species such as massive Porites boulders and encrusting Montipora.

Thilas and Giris

Thilas are submerged reef pinnacles that rise from the atoll floor but do not break the surface. Giris are similar but come closer to or just reach the waterline. Both are magnets for marine life and are popular dive sites. Strong currents channel nutrients across these formations, attracting manta rays, sharks, and large schools of fish.

Channel Reefs (Kandu)

The breaks in the atoll rim, known locally as kandu, allow ocean water to flow in and out of the atoll with the tides. The walls of these channels are draped in soft corals, sea fans, and sponges, and the currents draw pelagic species including grey reef sharks and eagle rays. Channel dives are among the most thrilling experiences in the Maldives.

Common Coral Species

While a full catalogue would fill a book, here are some of the corals you are most likely to notice.

• Acropora (staghorn and table corals) — Fast-growing branching and tabletop formations that provide shelter for small fish. Highly sensitive to temperature changes.
• Porites (massive corals) — Large, dome-shaped colonies that can live for hundreds of years. More resistant to bleaching than branching corals.
• Pocillopora (cauliflower coral) — Compact, bushy colonies common on reef flats and in shallow water.
• Millepora (fire coral) — Not a true coral but a hydrozoan. Recognisable by its smooth, mustard-yellow surface. Delivers a painful sting on contact, so keep your distance.
• Soft corals and sea fans — Found on deeper walls and overhangs, these filter-feeding animals add dramatic colour to the reef, particularly in shades of purple, pink, and orange.

Coral Bleaching in the Maldives

Coral bleaching occurs when sea temperatures rise above the normal range for an extended period. Stressed corals expel the symbiotic algae (zooxanthellae) that give them colour and provide most of their energy. Without these algae, the coral turns white and, if conditions do not improve, eventually dies.

The Maldives has experienced several major bleaching events. The 1998 El Nino caused catastrophic damage, killing an estimated 90 percent of shallow-water corals in some atolls. Subsequent events in 2016 and 2020 caused further harm. Recovery is possible — many reefs have bounced back impressively — but repeated bleaching shortens recovery windows and weakens reef resilience.

Conservation and Restoration

The Maldives has taken meaningful steps to protect its reefs. Highlights include:

• Marine Protected Areas (MPAs) — Key sites like Baa Atoll, a UNESCO Biosphere Reserve, restrict fishing and anchor damage.
• Coral nurseries — Several resorts and NGOs operate coral propagation programmes, growing fragments on underwater frames and transplanting them onto degraded reefs.
• Reef-safe policies — Many islands have banned reef-harmful sunscreen and enforce no-touch snorkelling and diving rules.
• Citizen science — Projects like the Maldives Underwater Initiative invite guests to participate in reef monitoring surveys.

As a visitor, you can help by choosing reef-safe sunscreen, never touching or standing on coral, maintaining good buoyancy while diving, and supporting resorts and operators that invest in conservation. Learn more in our About the Maldives section.

Best Places to See Healthy Coral

While conditions vary from year to year, some areas are consistently rewarding for coral lovers:

• Baa Atoll — Protected as a UNESCO Biosphere Reserve, home to some of the healthiest reef systems in the country.
• South Ari Atoll — Excellent house reefs and thilas, with the added bonus of regular whale shark encounters.
• Vaavu Atoll — Less visited and home to pristine channel reefs with exceptional soft coral growth.
• North Male Atoll — Classic dive sites like Banana Reef and HP Reef showcase mature coral gardens within easy reach of the capital.