Southwest Tobago

Coral Reefs of Southwest Tobago, then and now

To create a new record for The Maritime Ocean Collection, Anjani Ganase dived coral reefs in southwest Tobago. This is the first time she is observing these reefs through the eyes of a scientist. She compared what she saw with descriptions by Richard Laydoo from the Institute of Marine Affairs during the 1980s, about 35 years ago, in the book, A Guide to the Coral Reefs of Tobago

Diving in the southwest Tobago is a hotter and sunnier experience, compared with diving along the steep edges of the main ridge in the northeast. The brightly lit waters and whiter sand give the coral reefs a picturesque ambiance; but the coral reefs here also display a complex history of disturbance and some surprises.


A school of grunts seek refuge under an a very old anchor on Flying Reef. Video by Anjani Ganase | The Maritime Ocean Collection

Along the southern coast, Flying Reef is exposed to the Atlantic Ocean with the strong currents which gives the reef its name. Flying Reef sits about 1 km off shore and runs parallel to the airport runway, but while planes were talking off to the east; divers would be swept to the west. Laydoo in 1984 described Flying Reef as a gentle sloping reef littered with sea fan and soft corals fluttering in the current. The most prominent feature here was the dominant star coral, reef builders that layered the seascape along with Elkhorn corals branching up towards the surface, while giant barrel sponges lined the reef base.

While the hard coral infrastructure is still present, diving on this reef today is a very different experience. Large sections of the reef framework appear to have been converted to rubble, and the hard coral has been replaced by macroalgae and sponges on much of reefscape. Bright yellow and purple sponges congregate around the bases of sea fans and soft coral plumes as well as the brain corals that still occur. Massive barrel sponges were still spotted along the deeper sections of the reef. Sponges in general make up a large portion of the reef community. The fish life at Flying Reef however is still very impressive: it is the only reef where a black tip reef shark was spotted; adult Parrotfish were common, including the large Rainbow Parrotfish not seen anywhere else on the island and a rarity on many Caribbean reefs. Large schools of grunts and chub would gather around the existing coral mounds.


From Buccoo Bay, Buccoo Reef extends southwards arching its way to Pigeon Point. It is a unique reef system seen nowhere else in Trinidad and Tobago, and is special because it is a natural beauty, primarily because of the growth of the hard corals. The sheltered mangroves and lagoon persist because of the protection afforded by Buccoo Reef. Another unique feature of Buccoo Reef is the presence of back reef and patch reefs occurring in the lagoon behind the reef. Laydoo described the presence of many reef patches as consisting of thickets of branching corals such as the fragile Staghorn as well as finger coral. Pockets of vibrant life within the lagoon. However, even back then, there were fields of coral rubble along the reef flat because of storm and anchor damage as well as over twenty years of walking on the reef. Thirty years after Laydoo’s observations many of the patch reefs do not exist. Yet, the famous patch reef, known as Coral Gardens composed of primarily of star corals, still sparkles below the surface in a relatively healthy state.

The Buccoo’s seaward slope is a more depressing scene. Here is how Laydoo described the outer and eastern sections of Buccoo Reef:

“Generally, the reef crests, particularly at the Outer and Eastern reefs, are emergent or exposed at low tide. The fauna of the reef flats is composed mainly of elkhorn coral, finger coral, fire coral and sea carpet (palythoa).”

The section of reef where the Elkhorn corals once dominated is now a barren zone. It’s strange that the skeletal remains of Elkhorn still stand out against the blue water, as if they died yesterday; nothing significant has grown over them, only turf algae and come calcifying algae. It’s as if the reef has been suspended without regrowth or recovery. During the 1970s and 80s, Elkhorn corals across the Caribbean were wiped out by disease.

As we moved farther down the reef slope, the coral and marine life resemble what was described by Laydoo, with the boulder brain and star corals occurring in deeper water:

“the forereef, characterized mainly by large boulder-type formation of brain and star coral slopes gently to merge with the sandy seafloor”


Continuing east, one bay over from Buccoo is Mt Irvine Bay. The eastern section of the Mt Irvine Bay near the headland is one of the most popular surf spots on the island but below the waves is a well developed coral reef. As you round the point into Back Bay, the reef structure ebbs and the fish frequent the rocky outcrops; the submerged cliff and crevices a natural refuge for schools of juvenile fish. Sections of Mount Irvine reef still resemble Laydoo’s descriptions with conspicuous colonies of boulder brain and star corals, but large sections of reef slope have become over run by swaying soft coral plumes. The most fascinating feature of this reef is the structure itself. It was amazing to peer through the lattice of the reef framework. At 10 m depth at the top of the reef, I spied a network of tunnels and corridors extending at least another 10 m into the reef; a sort of reef underworld created by years and years of hard corals growing on top of each other. The fish used these secret passageways to escape my camera lens.


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Farther north of Mt Irvine lies the small bay, Arnos Vale. Most of the reef lies within the shallow bay and does not extend far beyond it. The beauty of the bay was as described by Laydoo, a meadow for the branching Elkhorn coral and a plenitude of fish living among it, making it a favourite snorkelling site. Unfortunately, few of these corals exist today, yet there is some reef life within the bay. Laydoo described the reefscape outside the bay consisting of submerged rocks and boulders with little hard coral growth. There may be something that naturally limits coral growth on these rocks, as they lack coral growth to today. Taking a closer look, you can find encrusting sponges, fire coral and sea fans coating surfaces of the rocks. The seascape is beautifully structured with rocky canyons and swim throughs where reef fish congregate.


Culloden reef is located farther north of Arnos Vale. The reef spreads out seaward from the two headlands of the bay and, connecting in the middle, creates a horseshoe shape. This unique reef system developed a spur and groove formation as a result of moderate wave energy moving along the coastline. This reef features spurs that spread out like fingers along the seafloor because of the growth and accumulation of hard corals. In between the spurs are narrow sand channels where dissipating wave energy moves sediment and rubble down the slopes to collect in these grooves. Laydoo remarked on the pristine conditions of corals that made up the spurs of Culloden Reef compared to other reefs on the island, with the presence of fish and shark life that gather in the grooves. He recommended that it be designated a scientific reserve to be studied further.

Today the reef structure is still impressive and while some hard corals continue to grow along the spurs, there is now heavy competition with the sea fans and rods that overshadow, brush and scour the star boulder corals. We did not find any sharks in the sandy grooves, instead a hoard of lionfish lurking under coral overhangs.


Laydoo, R. S. (1991) A Guide to the coral reefs of Tobago, Institute of Marine Affairs.


Coral Gardens Reef sits behind Buccoo Reef in the Bon Accord Lagoon. This reef is made up of boulder star coral (Orbicella annularis) and home to large schools of reef fish. Photo by Anjani Ganase | The Maritime Ocean Collection

Just outside of Arnos Vale Bay divers can swim through underwater canyons and explore submerged rocks. Photo by Anjani Ganase | The Maritime Ocean Collection

Brain corals dominate a section of Mt Irvine Reef. Photo by Jonathan Gomez | The Institute of Marine Affairs

A school of creole wrasse pose for the camera at Culloden Reef. Photo by Jonathan Gomez | The Institute of Marine Affairs


A school of grunts seek refuge under an a very old anchor on Flying Reef. Video by Anjani Ganase | The Maritime Ocean Collection

A view of the reef at Mt Irvine Reef. Video by Anjani Ganase | The Maritime Ocean Collection

This swim through at Mt Irvine Wall is a hide out for schools of juvenile reef fish. Video by Anjani Ganase | The Maritime Ocean Collection



Located north of Charlotteville, this island is a bird sanctuary and home to a number of nesting species, including the Magnificent Frigatebird and the Brown Booby. Coral reefs surrounding St Giles are exposed to high currents that form reefs dominant in brain corals that cover the shallow areas.


Along the south coast of Tobago are three dives sites. From east to west, they are Cove Reef, Flying Reef and Stingray Alley. Coral reefs in this area are gently sloping and exposed to high currents. These are the haunts of large schools of reef fish including grunts and chub.


Sanga Rock is located in north Charlotteville. The sheltered side of Sanga Rock is home to a unique coral reef dominant in boulder and brain corals. Divers swim around Sanga Rock and explore the walls that are encrusted with the beautiful non-native sun cup corals that resemble bunches of yellow flowers.


Just off Plymouth Point (adjacent to the Plymouth recreational grounds), this well-developed spur and groove reef is dominant in sea plumes and sea rods.


Pirates Bay reefs consist of two small patch reefs located on either side of Pirates Bay in Man-O-War Bay, Charlotteville. This shallow coral community grows over sunken rocks. The reef is home to encrusting fire coral and hard corals, numerous long-spined sea urchins and sea rods. Many reef fish and juvenile marine turtles visit these reefs.


Little Tobago is the larger island located in Speyside Bay. This island is home to marvels both above and below the water including one of the largest brain corals in the Western Hemisphere. Coral reefs encircle Little Tobago. The island is an important nesting site for marine birds, including the Red-billed Tropic Bird.


Landslide reef runs along the eastern margin of Man-O-War Bay from Pirates Bay out towards Breakfast Bay. This is a shallow fringing reef dominated by hard and soft corals growing along submerged rocks. It is home to rare branching Elkhorn coral.


Iguana Bay is located north of Charlotteville and can only be accessed by boat. Although there are coral communities, there is little structure, likely because of the exposed wave environment. It is home to some colonies of the incredible rare Acropora cervicornis.


Hermitage reef lies along the eastern side of Man-O-War Bay, Charlotteville, adjacent to Hermitage Bay. With no coastal development nearby, this coral reef is home to the endangered branching Elkhorn corals in the shallows. Farther down the reef slope, giant mountain star coral colonies extend from 7 m to 15 m in depth, creating underwater structures for numerous marine creatures.


Located off Speyside, Goat Island features a house nestled between two giant rocks. Coral reefs wrap right around the island. The most famous reef is called Angel Reef, which lies along the western bay; it is dominant in hard corals and is one of the more biodiverse reefs on the island. Japanese Gardens on the south side of the island is well-known for its colourful sponge communities.


This quaint bay lies along the Caribbean coast between Castara and Parlatuvier. The bay is lined with coral reef communities including small colonies of the very rare Staghorn coral that can be seen when snorkelling. The deeper coral reefs are dominant in sea plumeas and boulder corals.


Diver’s Dream consists of a series of shallow reef banks found 4 km off the south coast of Tobago between Trinidad and Tobago. The banks are covered by giant barrel sponges that thrive in the high currents. Encrusting coral and macroalgae are also prominent at this site. The banks are often visited by pelagic marine life, such as turtles, sharks and barracuda.


Culloden Bay is home to a unique spur and groove coral reef formed by water movement. The growth of corals over time has created these rocky underwater spurs that project out to sea like fingers. Each spur is separated by a sandy groove where one can find turtles, eels and lionfish lurking.


This remote bay is adjacent to Castara Bay. It is usually accessed for diving by boat. Cotton Bay consists of a series of submerged rocks for an amazing swim through for divers and hideout for marine life. Encrusting and boulder corals grow along these giant submerged rocks that descend to great depth.


The reef fringes the eastern margins of Castara Bay extending from Heavenly Bay out of the bay. Castara reef is a popular for snorkelling with the rare branching Elkhorn corals close to the rocks. For divers, the reef is dominant in soft coral plumes that make perfect hiding spots for juvenile turtles.


On the eastern side of Man-O-War Bay, this reef is accessible only by boat. The rocky shoreline extends underwater to house branching and bouldering corals on submerged rocks and abundant fish life seeking refuge between the reef and the rocks.


Booby Island is located within the sheltered Man-O-War Bay at Charlotteville in northeast Tobago. It is named after the Brown Boobies that inhabit the rock. On one side a gently sloping reef dominant in sea plumes and corals connects the island to the mainland at Lover’s Bay; on the other side, divers can explore the submerged rock walls of the island.


Arnos Vale Bay on Tobago’s Caribbean coast is a popular snorkel and diving destination, including night diving in the bay. The Arnos Vale reef extends outward from the bay along the eastern and western fringes, where the reef grows on submerged rocks. Divers can swim through channels covered in corals, sea fans and sponges.

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