most pristine temperate ecosystems on the planet. Various species of whales and dolphins can be seen around Tristan from time to time with increasing sighting rates, although recovery of baleen whales, especially the southern right whale, were severely hindered by illegal whaling by the Soviet Union in the aftermath of the 1960 volcanic eruption. The subantarctic fur seal (Arctophoca tropicalis) can also be found in the Tristan archipelago, mostly on Gough Island. The biodiversity of marine life is limited given the islands' isolation, making identifying the impacts of invasion difficult. While much of the marine life is unknown there has been an invasive species identified in the waters around the islands. This species is the South American silver porgy (Diplodus argenteus argenteus) which is thought to have sought refuge in the area due to the wreck of an oil platform off the coast of Tristan in 2006. The silver porgy is omnivorous but is not linked to the consumption of the valued lobster populations that the islanders fish. The silver porgy is however suspected to be consuming components of the islands’ fragile kelp forest. The giant kelp forests of Macrocystis pyrifera were extremely limited in biodiversity and has a simple, short-chain food web. While this species is considered non-native and invasive, removal efforts are currently not prioritized. Continued monitoring is suggested and expedition research for all invasive marine species are ongoing. Economy The island has a unique social and economic structure in which all resident families farm and all land is communally owned. Outsiders are prohibited from buying land or settling on Tristan. Besides subsistence agriculture, major industries are commercial fishing and government. Major export industries are the Tristan rock lobster (Jasus) fishery, the sale of the island's postage stamps and coins, and limited tourism. Like most British Overseas Territories, it was never a part of the European Union, but was a member of the EU's Overseas Countries and Territories Association. The Bank of Saint Helena was established on Saint Helena and Ascension Island in 2004. This bank does not have a physical presence on Tristan da Cunha, but residents of Tristan are entitled to its services. Although Tristan da Cunha is part of the same overseas territory as Saint Helena, it does not use the local Saint Helena pound; sterling is used directly instead. The island is located in the South Atlantic Anomaly, an area of the Earth with