Great Basses Reef Marine Life: What You Will Actually See

Green Sea Turtle Occasional

Chelonia mydas

The great grazing turtle of the tropics, the only sea turtle that turns vegetarian as an adult.

Where: Resting on ledges and feeding on the reef. Best: March to April.

Hawksbill Turtle Occasional Critically Endangered

Eretmochelys imbricata

The reef's sponge specialist, its beautiful shell also the reason it was hunted to the edge.

Where: The reef structure and its overhangs. Best: March to April.

Bigeye Trevally Regular

Caranx sexfasciatus

A silver predator that gathers by day in vast, slow-turning tornadoes of fish, one of diving's great spectacles.

Where: Schooling in the current. Best: March to April.

Bluestripe Snapper Regular

Lutjanus kasmira

A bright yellow snapper ruled with electric-blue lines, massing in dense, glowing schools around coral heads and wrecks.

Where: Dense shoals holding station in the lee of the reef structure. Best: March to April.

Coral Grouper (Coral Hind) Regular

Cephalopholis miniata

A vivid orange-red grouper freckled all over with electric-blue spots, lurking at the mouth of a coral cave.

Where: Reef gullies and overhangs. Best: March to April.

Giant Moray Regular

Gymnothorax javanicus

The largest moray on the reef, its gaping, fanged mouth a fearsome look that is really just how it breathes.

Where: Holes and cracks in the sandstone reef. Best: March to April.

Giant Trevally Regular

Caranx ignobilis

A silver battering ram that hunts by simply outrunning everything, and has been filmed taking birds off the surface.

Where: Hunting in the current over the reef. Best: March to April. Trevally hunt the reef edge here in numbers that do not happen on the sheltered coasts.

Great Barracuda Regular

Sphyraena barracuda

A silver torpedo with a fearsome underbite, sometimes gathering in slow, glittering spiral schools over the reef.

Where: Hanging in the current above the reef. Best: March to April.

Moorish Idol Regular

Zanclus cornutus

An unmistakable disc of black, white and gold trailing a long ribbon fin, one of the most elegant fish on any reef.

Where: Reef top and the shallower ledges. Best: March to April.

Powder Blue Surgeonfish Regular

Acanthurus leucosternon

A stunning Andaman signature fish, powder blue with a yellow sail and a scalpel-sharp blade at the base of its tail.

Where: Shoaling over the reef top in the surge. Best: March to April.

Common Lionfish Occasional

Pterois volitans

A flamboyant reef hunter fanned out in maroon and white plumes, every graceful spine tipped with venom.

Where: Hanging under the ledges out of the current. Best: March to April.

Dogtooth Tuna Occasional

Gymnosarda unicolor

A heavy-shouldered blue-water hunter that materialises out of the deep at reef pinnacles to smash into bait schools.

Where: Blue water at the reef edge. Best: March to April.

Emperor Angelfish Occasional

Pomacanthus imperator

A living work of art in electric blue and yellow stripes, its young disguised in a maze of blue and white rings.

Where: Ledges and swim-throughs in the reef structure. Best: March to April.

Giant Grouper Occasional

Epinephelus lanceolatus

The giant of the reef, a grouper that can grow larger than a diver and swallow prey the size of a small shark.

Where: Ledges and gullies on the Great Basses reef. Best: March to April. The Basses hold the biggest reef fish in Sri Lankan water, because the conditions keep the fishing pressure off.

Longfin Batfish Occasional

Platax teira

A tall, disc shaped silver fish that drifts around wrecks and reefs with the calm curiosity of a friendly ghost.

Where: Mid water above the reef, often curious about divers. Best: March to April.

Oriental Sweetlips Occasional

Plectorhinchus vittatus

A handsome striped reef fish whose fussy juveniles wobble around in polka dots to mimic toxic flatworms.

Where: Under overhangs on the sheltered side. Best: March to April.

Titan Triggerfish Occasional

Balistoides viridescens

The reef's bad tempered bulldozer, a big triggerfish that will charge divers who stray over its nest.

Where: Reef top and sand patches. Best: March to April.

Humphead Wrasse (Napoleon Wrasse) Rare Endangered

Cheilinus undulatus

A giant, curious reef fish with thick lips and a bulging forehead, able to crunch prey that few other animals can eat.

Where: Deeper reef and gullies. Best: March to April.

Blacktip Reef Shark Occasional Vulnerable

Carcharhinus melanopterus

The neat little reef shark of the shallows, its black-tipped fins often cutting the surface over sun-lit sand flats.

Where: The shallower reef margins. Best: March to April.

Grey Reef Shark Occasional Endangered

Carcharhinus amblyrhynchos

The classic requiem shark of the drop-off, bold and inquisitive where currents sweep the reef.

Where: The reef edge and drop-offs. Best: March to April.

Whitetip Reef Shark Occasional Vulnerable

Triaenodon obesus

A slender reef shark that rests motionless in caves by day and hunts the reef in packs by night.

Where: Resting under ledges by day. Best: March to April.

Reef Manta Ray Rare Vulnerable

Mobula alfredi

A four metre wingspan gliding overhead in slow, hypnotic loops that leave divers grinning for days.

Where: Passing in the current over the reef tops. Best: March to April.

Whale Shark Rare Endangered

Rhincodon typus

The biggest fish in the ocean, a spotted, bus sized filter feeder and the undisputed holy grail of tropical diving.

Where: Open water at the reef. Best: March to April. Records cluster around the Basses in the short diving season.

Giant Sea Fan (Gorgonian) Regular

Annella species

A great lattice fan spread across the current, a soft coral that farms the flow for plankton and shelters seahorses and hawkfish.

Where: Current swept reef faces. Best: March to April.

Black Coral Occasional

Antipathes dichotoma

Colonies have been aged at over four thousand years, making them among the oldest living animals on the planet.

Where: Deeper gullies and overhangs. Best: March to April.

Feather Star (Crinoid) Regular

Comatulida species

A living bouquet of feathery arms that clings to high points on the reef by day and can crawl, or even swim, to a better spot.

Where: Clinging to the sea fans and reef edges in the current. Best: March to April.

Ornate Spiny Lobster Occasional

Panulirus ornatus

Migrates in single file across open seabed, hundreds of lobsters nose to tail, sometimes for hundreds of kilometres.

Where: Crevices in the reef. Best: March to April, after dark.