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Silhouette island

Silhouette island

Silhouette Island National Park was designated on 7th August 2010. A history of conservation on Silhouette island can be found in Phelsuma voulme 19.

Although Silhouette is the third largest island in Seychelles and Mont Dauban the second highest mountain (740m), the island's steep slopes have prevented significant development and restricted the population to 147 people at the present time. As a result, human impact has been less significant than on other islands and much of the original nature of the Seychelles islands is preserved on Silhouette.

The height of the mountains and the limited amount of development means thatthe island has an exceptional range of unique animals and plants.  Itis regarded by conservationists as one of the most important biodiversityhotspots in the Indian Ocean.  Silhouette is recognised as a prioritysite for conservation by theAlliancefor Zero Extinction.  

Read: Silhouette - Nature's Island

Anse Patates

Geology

Most of Silhouette is formed of 63 million years old granites. As with theother granitic islands in Seychelles these rocks are remains of the ancientsouthern super-continent Gondwana. This geological history means that theislands are the sunken remnants of the mountains of a continent once joinedto India and Madagascar. Clinging to these mountain-tops are the remainsof the flora and fauna that coexisted with the dinosaurs. At the time whenthe dinosaurs became extinct, part of Silhouette was covered by a volcano,traces of which can still be found.

History

Silhouette was the first island of the group to be seen when the islandswere discovered in 1609 but was not settled until the early 19th century.

From 1860 attempts were made to develop parts of the island for agricultureor forestry.  A wide range of plants was introduced for crops of timber,fruit, spices and oils. These are all abandoned now but the plants can stillbe found growing in the most unlikely places. In the 1940s a small groveof Coco-de-Mer trees (Lodoicea maldivica) was planted high in themountains. This thriving population of this rare palm provided an occupationfor part of the 1000 strong labour force on the island, some of whom hadto climb up to the trees to water them daily. The dramatic legacy of theisland's history; a cast-iron neo-classical mausoleum, is the most remarkablepiece of eccentricity in all Seychelles.

Since 1983 the island has been managed by the Islands Development Company(IDC).

Conservation and the Silhouette Conservation Project

In 1987 the waters around Silhouette were declared a Marine National Park and the rest of the island was protected as the Silhouette National Park in 2010.In 1994 the IDC invited The Nature Protection Trust of Seychelles (NPTS)to assist with conservation management of the island. In 1997 the NPTSestablished its Silhouette Conservation Project on the island. This projectaimed to protect the forest environments of Silhouette and to restore themto a near-natural state. A large part of the conservation work involved researchinto the diversity and ecology of the forest animals and plants. Anotherimportant aspect was the control of invasive species. This work came to an end in 2011 when the Seychelles government organsiation which owns Silhouette evicted conservationists from the island. 

The NPTS Seychelles Giant Tortoise ConservationProject used to be based on Silhouette.

chameleonPlants and animals of Silhouette

The NPTS has conducted research on Silhouette's biodiversity since the early1990s. This has led to the compilation of a full species list, coveringnearly 2,000 species. This has been published in the NPTS journalPhelsuma.

The majority of plant and animal species are small and inconspicuous. Themost obvious animals are the large fruit bats (Pteropus seychellensis),abundant bird life, day geckos (Phelsuma spp.) and skinks (Mabuyasechellensis, Pamelascincus gardineri and Janetascincus braueri).There are many inconspicuous or secretive animals, most dramatic ofwhich is the Seychelles chameleon (Calumma (formerly Chemaeleon)tigris). Both hawksbill turtles (Eretmochelys imbricata)and green turtles (Chelonia mydas) nest on the island. Theisland is of great importance as it supports the last known major roosts of theSeychelles sheath-tailed bat(Coleura seychellensis).

day gecko Results of NPTS research on Silhouette island can be found in our 2009 report and 2010 report.