
Falkland Islands Robin Woods, Rebecca Ingham and Ann Brown Michael Gore (rspb-images.com) Michael Black-browed Albatrosses General introduction The Falkland Islands are situated in the South Atlantic precipitation is 635 mm at Stanley, which has the longest between latitudes 51°S and 53°S and longitudes 57°30'W series of reliable climatic records. Average monthly and 61°30'W. They cover an area of 4,700 square miles temperatures range from 9°C in January to 2°C in July. 2 (12,173 km ), with two main islands, East and West Biodiversity Falkland, and about 750 smaller offshore islands and islets Birds (Woods 2001). The Falkland Islands are especially important in an Physiography international context for their seabird and marine mammal The Falkland Islands are composed of sedimentary rocks: populations. The rich coastal waters are very productive, the landscape is generally rugged and hilly, with the with the northerly Falklands Current to the east of the highest peaks being Mount Adam (700 m) on West islands bringing cold, deep nutrient-rich water from the Falkland and Mount Usborne (705 m) on East Falkland. Antarctic and providing the basis for the marine food web. East Falkland is divided into two large land blocks, Abundant productivity leads to a wealth of marine life, connected by a narrow isthmus. The southern block is supporting vast colonies of top predators such as dominated by the plain of Lafonia, an area of gentle relief albatrosses, penguins and seals. Colonies of nocturnal and open grasslands, while the area to the north is more burrowing petrels are known from a few islands; probably rugged and rocky, with large upland areas of peat bog and others are still to be discovered and all need to be permanent pools. West Falkland is generally more rugged, surveyed. More than 70% of the world population of Black- with an undulating landscape of open plains and upland browed Albatrosses and 75% of the world population of the acid grasslands. The coastline is deeply indented around southern form of Rockhopper Penguins breed in the both East and West Falkland (Aldiss and Edwards 1999). Falklands. Climate Marine mammals The Falkland Islands have a cool-temperate oceanic Around the coasts, Southern Sea Lions Otaria flavescens and climate, characterised by persistent strong winds, Southern Elephant Seals Mirounga leonina breed in colonies particularly in the spring and summer. Rain falls on of up to 300 pairs, and at a few remote rocky sites there are approximately half the days of the year, though there tends colonies of up to several thousand South American Fur to be more in summer, and the average annual Seals Arctocephalus australis. 99 100 0 50 100 kilometres FK007 intheUnitedKingdomOverseasTerritories Areas Important Bird FK017 FK013 FK014 FK008 FK019 FK020 FK021 FK012 FK006 FK009 FK011 Falkland Islands FK002 FK022 FK010 FK005 FK003 FK004 FK016 FK018 FK015 FK001 Falkland Islands Vegetation There are 177 recorded introduced plant species. Some The natural vegetation consists of coastal fringes of Tussac native plants appear to have a very restricted range limited Grass Poa flabellata, oceanic heath, acid grassland, peat bog to one location, such as the Moore’s Plantain Plantago and upland feldmark communities (Clark 1991). Tussac is moorei, from the south-west corner of West Falkland, and the tallest native plant in the Falklands and originally the Fuegian Violet Viola magellanica, recorded only in the formed stands around the coasts, extending at least 200 m south-east of the archipelago on Sea Lion Island. and sometimes 800 m inland, and covered small islands. It A published Red Data List includes 23 plants considered to is very long-lived and on Beauchêne Island, one large be threatened (Broughton and McAdam 2002b). Many of healthy plant was shown to be at least 300 years old (Smith these are restricted in range to ungrazed offshore islands and Prince 1985). The mature plant develops a fibrous and areas inaccessible to grazing animals, such as within pedestal (Tussac-bog) about 1–1.5 m high and 3 m or more stone-runs and on mountain ledges. An inventory of lower in circumference; from the crown spring thousands of plants is incomplete. The moss flora includes at least 168 leaves and stems up to 1.5 m long and the whole plant may species and subspecies, of which 43 have not been recorded reach a height of 3.5 m. As they die, the leaves and stems outside the Falklands (Greene 1983). There are also 127 fold down and are retained for years as a skirt between the known liverworts, including three endemics (Engel 1972). pedestal and the growing leaves before eventually falling. Adjacent plants in mature Tussac grassland are so close Land mammals together that skirts interlace completely and are difficult to Currently, there are no native land mammals on the penetrate. However, tunnels carpeted with leaf-litter Falklands. However, in the late 18th century, at the time of between the bogs are kept open by the movements of the early settlers, there was one native species, the Falkland penguins, seals, petrels and shearwaters. Tussac is very Fox or Warrah Dusicyon australis. This bold and inquisitive important for a great variety of Falkland birds, from the fox was described by early settlers but was never very Falkland Grass Wren to the Striated Caracara, providing numerous. It was larger than its close South American nest sites, shelter from wind and food sources for the relatives and was said to have hunted in small groups. majority of the resident species. With a government bounty to encourage them, sheep farmers had hunted the Warrah to extinction by 1876. On the main islands and many of those offshore, the vegetation has been degraded by accidental or agricultural Invertebrates burning and grazing by sheep, cattle, pigs, horses and, In a land without native trees, reptiles, amphibians or more recently, Guanaco Lama guanicoe, Reindeer Rangifer surviving terrestrial mammals, the insect life forms a very tarandus and goats. In particular, Tussac has almost important part of the islands’ ecology (Robinson 1984). disappeared from the coasts of East and West Falkland, and Over 350 insect species have been recorded, with new only survives in its original state on some relatively species continuing to be discovered. Most native species are inaccessible and remote offshore islands. The main islands closely related to those found in Patagonia and Tierra del are dominated by oceanic heath, with Whitegrass Cortaderia Fuego. Prevailing westerly winds and ocean currents are pilosa, a range of cushion plants and small shrubs. Bush likely to have aided their arrival. A reduction in wing size, and shrub associations are found inland on well-drained and indeed absence of wings, is a feature of many Falkland slopes with bog communities on poorly drained areas. insects, in common with other island systems. This is Feldmark vegetation occurs above 600 m and on lower thought to be the result of a trade-off between the high exposed slopes with mineral soils, with cushion-forming costs of wing development and the reduced need for plants and associated mosses and lichens. Vegetation on the dispersal on small islands, combined with the threat of the smaller ungrazed offshore islands is generally dominated removal of actively flying individuals out to sea. In the by dense Tussac, which flourishes particularly where Falklands, with its frequent high winds, this is a real burrowing birds aerate and fertilise the soil. There are no hazard. The introduced species, many of European origin, native trees, although many settlements have shelter belts are relatively recent arrivals, colonising these islands as a of introduced European Gorse Ulex europaeus and trees of direct result of human activities (Jones 2004). several species, particularly Monterey Cypress Cupressus Threats to the Falklands’ biodiversity macrocarpa, pines, spruces, eucalyptus and poplar trees. Threats to the biodiversity of the Falklands have included Kelp beds are common around the coasts, often extending the deliberate introduction of herbivorous animals for offshore for several hundreds of metres, where they farming and the accidental introduction of predators such provide nursery grounds for fish and squid (Clark and as rats Rattus spp. and the House Mouse Mus musculus, and Dingwall 1985, Patterson 1986, Oldfield 1987). cats as pets (many of which have become feral). Hepburn et al. (1992) describe wetlands in some detail. In Domesticated pigs, goats, cattle and horses introduced in their report, they identify over 100 wetland sites in the the 18th and 19th centuries on to the two main islands and Falklands that may be important for wildlife. Ongoing several other islands have, together with the burning of survey work is currently updating this list. maritime Tussac communities in the early 1800s by itinerant sealers, led to the loss of important habitats. The The vascular plant flora consists of 171 native taxa rapid development of sheep farming from the 1860s has (Broughton and McAdam 2002a, Broughton and McAdam compounded this effect. The burning of Whitegrass in 2005) of which 14 are currently considered to be endemic. 101 Important Bird Areas in the United Kingdom Overseas Territories attempts to improve pasture for grazing (Bourne 1988) and sectors: overseas wildlife and game fishing enthusiasts; the current trend in pasture improvement programmes is cruise ships; and the local civilian and military affecting the native vegetation over an increasing area of communities. Cruise ship visits have increased from 5,000 the islands. There is concern at the lack of environmental passengers in the 1995/96 season to over 40,000 in the impact regulations for this and other agricultural 2005/06 season. This rise in numbers is mostly due to an developments (Dunnet 1983). increase in the number of large, luxury vessels and a worldwide development of the cruise industry.
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