The Falkland or Malvinas Islands (51°-53° S) lie some 310 miles off the east coast of South America and have botanical elements related to Patagonia steppe, to which biome they are sometimes assigned. They consist of two large islands and hundreds of smaller islands, islets and stacks. Deep fjords incise the coasts of both West Falkland and East Falkland.
The cool Malvinas Current, flowing northward from the Antarctic Circumpolar Current, depresses summer temperatures and prevents major temperature fluctuations throughout the year. The islands have a cool temperate marine climate characterized by strong westerly winds. Annual precipitation averages 25 in (640 mm). Proximity to the Drake Passage, where differing air masses converge, results in frequent storms.
Coastal lowlands are dominated by tall tussac grass (Poa flabellata), although it has been heavily impacted in many places by sheep and the past grazing of introduced reindeer and replaced by much the shorter, alien annual meadow grasses. Tussac forms a peaty pedestal; and its insulating thatch provides shelter and nesting sites for birds ranging from Magellanic Penguins to tiny Cobb’s Wren as well as breeding areas for seals. Sea birds and mammals contribute high concentrations of nitrogen and phosphorous, transported from the ocean, to the land. Drier, rocky ridges are covered with dwarf shrubs, especially the heath known as diddle-dee (Empetrum rubrum). Tall fern may be co-dominant with diddle-dee.
The Subantarctic Botanical Zone, in which the Falklands lie, is home to 24 graminoids, 32 forbs, 250 mosses, 150 liverworts, and more than 300 kinds of lichens. A great variety of marine birds breed on the islands, including Magellanic, Gentoo, and Rockhopper penguins, Black-browed albatrosses, several petrels, gulls, and geese. The flightless Falkland Steamer Duck is endemic. There are also a number of resident terrestrial songbirds, including endemic subspecies of Dark-faced Ground Tyrant, Cobbs Wren, and Falkland Thrush. Southern sea lions, fur seals, and elephant seals breed on the shores. The only native land mammal, the warrah or Falkland Islands Wolf (Dusicyon australis), was extinct by the late 1870s.
Tussac grass once dominated the coastal zone of many of the islands of the Falkland archipelago.
Diddle-dee heath grows on well drained sites at most elevations. Here it is accompanied by the erect reddish brown fronds of Fuegian Tall Fern and cushion plants such as Azorella selago and balsam bog (Bolax gummifera)
Gentoo penguin carries a pebble to its mate constructing a rim around nest site.
Rockhopper Penguins
Falkland Flightless Steamer Duck
Falkland Thrush, one of several endemic songbird subspecies on the islands.
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The warrah or Falkland Islands Wolf was already rare when Charles Darwin visited the islands in 1833 due to hunting for its fur and predator control. He predicted its extinction.
Painting by George E. Waterhouse in Darwin, C. R. ed. 1838. Mammalia Part 2 No. 1 of The zoology of the voyage of H.M.S. Beagle. By George R. Waterhouse. Public Domain.
Sheep raising is a major economic activity on the main islands and has destroyed much of the native vegetation. However, upland geese can still graze beside the sheep and Magellanic penguins can still burrow into grazed areas to nest.
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Sources: Quinn, Joyce A. 2008. Arctic and Alpine Biomes. Greenwood Guides to the Biomes of the World. Westport, MA, Greenwood Press. Strange, Ian. 1992. A Field Guide to the Wildlife of the Falkland Islands and South Georgia. London, HarperCollins.
