Lough Hyne

Lough Hyne is a fully marine sea lough in West Cork, Ireland, about 5 km southwest of Skibbereen. It was designated as Ireland's first Marine Nature Reserve in 1981.
Lough Hyne was probably a freshwater lake until about four millennia ago , when rising sea levels flooded it with saline ocean water. The lake is now fed by tidal currents that rush in from the Atlantic through Barloge Creek. The stretch between the creek and the lake is known as "The Rapids." The lake's small size, only 0.8 km by 0.6 km, creates an unusual habitat of highly oxygenated yet warm seawater that sustains an enormous variety of plants and animals, many of which are not found anywhere else in Ireland. A wide variety of environments such as cliffs, salt marsh, beach, and areas of greatly varying water movement add to the area's biodiversity. Some of the seawalls around the lake and the Rapids were built as relief work during the Great Hunger.

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