. Cold-water Coral Reefs: out of sight - no longer out of mind. UNEP-WCMC Biodiversity Series 22. Cold-water coral reefs Lophelia reefs occur in unusually shallow depths of less than 250 m. The shallowest reef is at only 39 m depth on the Tautra Ridge, middle Trondheimsfjord (Fossa et aL, 20021. Typical reef sites in fjords are sills that are kept free from sediment deposition by strong tidal currents. A good example has been described from the Stjernsund at 70°N, northern Norway (Figure 10; Freiwald et aL, 19971. Lophelia growth is well developed along the current- swept flanl<s of the sil
. Cold-water Coral Reefs: out of sight - no longer out of mind. UNEP-WCMC Biodiversity Series 22. Cold-water coral reefs Lophelia reefs occur in unusually shallow depths of less than 250 m. The shallowest reef is at only 39 m depth on the Tautra Ridge, middle Trondheimsfjord (Fossa et aL, 20021. Typical reef sites in fjords are sills that are kept free from sediment deposition by strong tidal currents. A good example has been described from the Stjernsund at 70°N, northern Norway (Figure 10; Freiwald et aL, 19971. Lophelia growth is well developed along the current- swept flanl<s of the sill at 220 to 260 m depth. However, on the shallower sill living sponge-octocoral communities grow on fossil coral rubble. Elsewhere in the world, Lophelia reefs have been described at the base of the Flonda-Hatteras Stope at depths of 500 to 800 m, and from the outer eastern edge of Blake Plateau, both off the southeastern United States, at 640 to 869 m depths (Stetson et aL, 1962: Reed, 2002a and bl. The maximum reUef of the pinnacle-shaped Lophelia reefs is 97 m. In the Florida Strait-Blake Plateau area, the corals are growing on dead, possibly fossil, coral rubble ridges. As these ridges are often consolidated they are called Tithoherms'. Paull et al. (20001 estimated the existence of over AO 000 lithoherms in the Florida Strait-Blake Plateau area. The lithoherms show a clear zonation of corals with L. pertusa and Enallopsammia profunda along the upcurrent slopes and the golden coral Gerardia sp. on top of the structure, with downcurrent assemblages of octocorals and stalked crinoids common (Messing et 19901. There are a number of Lophelia records from the Gulf of Mexico but only one has been confirmed (Schroeder et al., in pressl. The reef is located on the upper De Soto Slope, off Louisiana, at a depth of i3i to 510 m. and has a relief of i5 to 90 m (Schroeder. 20021. Individual colonies are as large as m in diameter and colony clusters measure by by A m.
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Keywords: ., bhlconsortium, bookcollectionbiodiversity, bookcont, bookyear2004
