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Wildlife of Saint Helena, Ascension and Tristan da Cunha

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Saint Helena, Ascension Island and Tristan da Cunha as well the other uninhabited islands nearby are a haven for wildlife in the middle of the Atlantic Ocean. The islands are home to a large number of endemic flora & fauna (see Flora of Saint Helena) as well as endemic birds, and a large number of endemic fish species, found in the reef ecosystems off the islands.

Birds of Saint Helena

On Ascension, there used to be a large number of endemic species of birds, all are now all but extinct off the main island, and the main breeding site is on Boatswain Bird Island. Over 10,000 birds breed on this tiny island, which is home to Ascension Frigate Birds, Red Footed, Brown and Masked Boobie, Shearwaters, Tropic Birds (red and yellow billed) (Also known as Boatswain Birds) and Petrels. The Sooty Tern, known locally as the Wideawake Tern (due to its distinctive call) is the most common bird on the island, and the airport on the island is named after this bird. The Ascension Rail is extinct from the island.

Saint Helena Island is not so much a major breeding site for seabirds as Ascension is, but it had more endemic birds, all but one of which are now extinct. The Wirebird (charadrius sanctaehelenae) is a type of plover which lives in burrows around the island, and is the national bird. It is called the Wirebird due to its thin legs that look like wire. Extinct birds on the island include the St. Helena Crake, the St. Helena Swamphen and most famously, the Giant Hoopoe.

Tristan da Cunha has the number of birds on a par with Ascension. Inaccessible Island and Gough Island are together a UNESCO World Heritage Site and a wildlife reserve due to the large number of breeding seabirds found there, including endemics. The birds include the Wandering albatross, Rockhopper penguin, Great Shearwaters Tristan thrush, Atlantic Yellow-nosed Albatrosses, and the Antarctic tern. The Inaccessible Island Rail is the world's smallest living flightless bird, is endemic to Inaccessible Island and not the mainland. The Tristan albatross is also native to the islands of Tristan da Cunha, as well as the Atlantic Petrel.

Mammals of Saint Helena

On both Ascension Island and Saint Helena Island, the only mammals are introduced cats and rats (accidentally introduced and kept as pets) as well as some cattle. Goats were introduced on Saint Helena by the Portuguese to provide passing ships with fresh meat.

Tristan da Cunha hosts breeding grounds for Subantarctic Fur Seals and Southern Elephant Seals, a number of whale species are also found in the waters around Tristan.

Marine Life of Saint Helena

Saint Helena and Ascension Island both have excellent and well preserved Coral Ecosystems, which are very diverse and contain a large number of endemic and non endemic fish. The following fish are endemic to Ascension Island; Resplendent Angelfish (Centropyge resplendens) Apollo Damselfish (Chromis sp.) Lubbock's Yellowtail Damselfish (Stegastes lubbocki) Ascension Goby (Priolepis ascensionis) White Hawkfish (Amblycirrhitus earnshawi) Marmalade Razorfish (Xyrichtys blanchardi) Seabream (Diplodus ascensionis) Ascension Wrasse (Thalassoma ascensionis) The following are found in both Saint Helena and Ascension Islands; Hedhog Butterflyfish (Chaetodon dichrous) Axillary-spot Cardinalfish (Apogon axillaris) Parrotfish (Sparisoma strigatum) Hogfish Island Wrasse (Bodianus insularis) The following fish are found only on the island of Saint Helena; St. Helena Butterflyfish (Chaetodon sanctaehelenae) St. Helena Flounder (Bothus mellissi) St. Helena Pufferfish (Canthigaster sanctaehelenae) St. Helena Wrasse (Thalassoma sanctaehelenae)

Green Turtles make a 3000 mile journey every 3-4 years from Brazil to Ascension Island to breed. They have been a protected species on the island since the mid 20th century and lay their eggs on the unspoilt beaches of the island. The turtles who survive to adulthood will return to breed on the island.

On Tristan da Cunha there is an endemic species of lobster; the Tristan rock lobster which appears on the coat of arms of the territory. Other marine life includes several temperate water fish species, as well as seals and whales listed above.

Flora of Saint Helena

See main article Flora of Saint Helena The Flora of Saint Helena is particularly diverse, with hundreds of endangered endemic species of tree and vegetation. In recent years there has been a programme to conserve and replant the great forest on the island which was destroyed over the years by human activity, causing widespread soil erosion on the island. The Millenium Forest Project has been successful and the forest is expanding rapidly. Here is a list of vascular plants endemic to Saint Helena: Monocotyledons

Dicotyledons

Pteridophytes (Ferns and fern-allies)

There are a few plants endemic to Ascension Island also, these include the Marattia purpurascens, Asplenium ascensionis, Xiphopteris ascensionense, Pteris adscensionis, Euphorbia origanoides & Sporobolus caespitosus. There are several other extinct species. Ascension contains one of the world's largest artificial forests, planted over the past hundred years with mainly introduced species, on Green Mountain. This has threatened the endemic species on the Island.

Insects of Saint Helena

Most insects on all the islands are also found elsewhere, one exception is the St. Helena Earwig (endemic to Saint Helena), the world's largest earwig. Though thought to be extinct, there is still a high possibility that it is still alive, though the construction of the new airport on Prosperous bay Plain won't help its survival chances, and there are desperate efforts to find living specimens so that they can be bred and re-introduced before construction starts on the New Airport.

Conservation

Conservation has been a big issue on Ascension Island, and the Ascension Heritage Society has been set up to help deal with the issues of conservation. There have been successful programmes for protecting Green Turtles, and the chartiy has worked hard with the RSPB to protect the birdlife on the island. The main activities going on at the moment are a cat and rat eradication programme, along with attempts to breed the native plant species on the island.

Sadly, most of Saint Helena's endemic birds became extinct long before man realised what he was doing and started the birds, rather than eating them. Still, Wirebird breeding programmes are on-going, although numbers are still falling. The Millenium Forest Project has been highly successful and has boosted the chances of Saint Helena's treasured flora & fauna, and this is the main concentration of conservation on the island.

Tristan da Cunha has had some extremely successful programmes in conservation, most notably of which is the world heritage site of Inaccessible Island and Gough Island. The low population has helped matters on the islands, as well as the non-exsistence of cats and other pests.

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