Seychelles Bank

Seychelles Bank
Sean.hoyland · Public domain · source
Name	Seychelles Bank
Location	Indian Ocean
Country	Seychelles
Archipelago	Seychelles Archipelago

Seychelles Bank is a large submerged continental fragment in the western Indian Ocean lying adjacent to the inner islands of Seychelles. The feature underpins many of the granitic islands of Mahé, Praslin, and La Digue and influences regional oceanography around Aldabra, Farquhar, and Cosmoledo. Studies of the Bank intersect work by institutions such as the Seychelles Maritime Safety Authority, the University of Seychelles, and the Royal Society.

Geography and location

The Bank occupies a broad platform between the Somali Basin, the Mascarene Plateau, and the Seychelles Plateau, extending seaward from the inner islands toward features like Amirante Islands and Alphonse Atoll. Its bathymetry has been mapped by expeditions from the National Oceanography Centre and by surveys linked to the International Hydrographic Organization, showing shelves, banks, and intervening channels near Praslin Island, La Digue Island, Curieuse Island, and the fringing reefs of Ste Anne National Park. The Bank lies within maritime zones governed under instruments involving the United Nations Convention on the Law of the Sea and has been subject to delimitation discussions involving the Mauritius and Madagascar sectors in the broader western Indian Ocean context.

Geology and formation

The Bank is part of a Precambrian to Mesozoic crystalline basement complex related to Gondwana breakup and rift systems that produced the Deccan Traps–adjacent magmatic provinces and the Mascarene Basin. Geologists working with the British Geological Survey and the Geological Society of London have linked its granitic cores to the Seychelles microcontinent that separated from the Indian Plate during the eruption of the Deccan Traps in the late Cretaceous–Paleogene interval. Lithologies include granite exposures on Mahé and Praslin analogous to outcrops studied in the Seychelles granite islands literature, with Mesozoic and Cenozoic cover sequences examined by researchers from the University of Oxford and the National Institute of Oceanography (India). Tectonic reconstructions by teams at the Scripps Institution of Oceanography and the Woods Hole Oceanographic Institution incorporate the Bank into models of plate separation, hotspot activity tied to the Réunion hotspot, and the formation of the Mascarene Plateau.

Ecology and biodiversity

The shallow platform and its fringing reefs support coral assemblages studied by the Callaway Institute, the Seychelles Islands Foundation, and international coral reef programs such as the Global Coral Reef Monitoring Network. Coral genera like Acropora, Porites, and Montipora coexist with seagrass meadows harboring species documented by the International Union for Conservation of Nature and by marine biologists from the University of Cambridge and National University of Singapore. The fauna includes populations of green sea turtles and hawksbill sea turtles that nest on islands such as Aride Island and Silhouette Island, seabird colonies like sooty terns and tropicbirds on islets referenced in studies by the Royal Society for the Protection of Birds, and economically and ecologically important fish taxa including groupers, snappers, and tunas exploited by fisheries monitored by the Indian Ocean Tuna Commission. Pelagic visitors include whale sharks and cetaceans such as bottlenose dolphins and humpback whales noted in surveys by the International Whaling Commission partners and marine mammal researchers at the Duke University Marine Lab.

Human history and use

Human interactions trace from early navigators in the Arab world and Austronesian voyagers through European exploration by the Portuguese Empire, Dutch East India Company, and later the British Empire. Colonial settlement concentrated on granitic islands like Mahé and Praslin where plantations established ties to the East India Company and to trade routes connecting Mozambique Channel ports and Réunion Island. The modern state of Seychelles developed governance institutions including the National Assembly (Seychelles) and ministries overseeing fisheries and environment, while research and management involve organizations such as the Seychelles Fishing Authority and the Seychelles National Park Authority. Contemporary economic activities tied to the Bank include artisanal and industrial fisheries licensed under frameworks with the Indian Ocean Tuna Commission, marine tourism linked to dive operations on La Digue and Praslin, and hydrographic charting by the International Maritime Organization-related services. Historical events intersecting the region include shipwrecks cataloged by the National Museums of Seychelles and wartime patrols during the Second World War.

Conservation and management

Conservation measures encompass marine protected areas managed by the Seychelles Islands Foundation, the designation of sites such as Aldabra Atoll as UNESCO World Heritage Sites, and policy frameworks developed with partners like the United Nations Environment Programme and the Global Environment Facility. Management strategies address threats identified by researchers at the International Union for Conservation of Nature and by the Food and Agriculture Organization including coral bleaching linked to El Niño–Southern Oscillation events, overfishing affecting stocks monitored by the Indian Ocean Tuna Commission, and invasive species documented by the International Council for Bird Preservation. Restoration and monitoring projects have been supported by NGOs like the Wildlife Conservation Society, the The Nature Conservancy, and academic collaborations with the University of Seychelles and Stellenbosch University. Regional cooperation includes initiatives under the Indian Ocean Commission and bilateral agreements with states such as Mauritius and France for ocean governance, maritime surveillance, and biodiversity conservation.

Category:Islands of Seychelles