It turns out, this remote Atlantic island has quite some wildlife. Dive in, says Scott Bennett, and you won’t be disappointed
mere 16km long and just under 10km wide, St Helena island is the dictionary definition of remote. Situated in the South Atlantic, 1900km west of southern Africa and 2900km east of South America, the island ascends 4000m from the ocean floor to its highest point at 820m above sea level.
Isolated islands are magnets for undersea life and St Helena is no exception. Bolstered by a mixture of currents, a diverse marine fauna can be found, with both Western and Eastern Atlantic and circumtropical species residing in St Helena’s waters. Water temperatures range from 19 degrees Celsius in winter to 25 degrees in summer.
Underwater, dramatic seascapes echo the volcanic terrain above, the rock faces etched with caves, archways, sea mounts and reefs. Although reef-building corals are absent, an abundance of tunicates, algae and sponges encrust the rock faces. Endemic orange cup corals add a splash of colour, along with harpoon weed (a red algae) and various species of hydroids.
Despite the lack of coral reefs, there is no shortage of fish life. Due to long-term isolation, the island is home to a wide variety of endemic species. Most prolific is the St Helena butterflyfish, whose numbers are simply astonishing. Schools are so dense that divers can virtually disappear within them.
More elusive are hedgehog butterflyfish, distinctively patterned with a chocolate brown head and lower half and white above. Masses of sergeant-majors and ocean surgeonfish ebb and flow across the reef, as squirrelfish and blackbar soldierfish congregate under ledges and overhangs during the daylight hours. Perfectly camouflaged, spotted scorpionfish sit motionless awaiting prey, while moray eels peer from rocky crevices.
What appears to be two parrotfish species is actually one. The endemic strigate parrotfish boasts two colour phases. It is theorised that the smaller, yellow versions are females while the larger, dull purple-grey individuals are the males. Other notable endemics include island hogfish, St Helena white seabream, flameback angelfish, Helena wrasse, St. Helena damselfish and Melliss’s conger.
Brown spiny lobsters and red Atlantic reef lobsters can be found in crevices and caves as well as ensconced within the island’s various wrecks. Numerous crab and shrimp species can also be seen, especially on night dives. Both green and hawksbill turtles are also observed, although there have been no records of successful nesting on the island.
A host of other widespread species can be observed. Amalco jacks are curious, frequently approaching divers. Chilean devil rays are often observed cruising the open water at many of the dive sites. A variety of pelagics have also been recorded, including skipjack and yellowfin tuna, wahoo, sailfish and swordfish.
St Helena’s waters are also home to a number of cetacean species. Spotted, rough-toothed and bottlenose dolphins are year-round residents, while humpback whales can be found between June and December. While individual whales are sighted in June, mothers with calves are sighted from July onwards, which indicates the females arrive to give birth.
During the summer months – between November and March – whale sharks congregate around the island in large numbers. Snorkeling guidelines are strict: participants must remain 3m away from the sharks and no touching is allowed. However, the sharks seem unaware of the rules and often approach snorkellers. Encounters with individual sharks are limited to 45 minutes.
All images copyright Scott Bennett
To learn more about the wealth of reasons to visit St Helena, visit www.sthelenatourism.com