Benthic community structure at a remote temperate rocky reef in the Gulf of Maine, Cashes Ledge

Abstract Cashes Ledge, in the central Gulf of Maine, is a diverse temperate rocky reef that rises from a depth of around 80 to around 9 m at the shallowest point. The Ledge is home to the full range of habitats found around the Gulf of Maine, compacted into an area measuring approximately 40 km by 10 km. It has been closed to bottom-tending fishing gear since 2002 and as such exists in a state largely unaffected by anthropogenic pressures. As a result it contains a wide variety of benthic organisms distributed among rock, boulder, cobble, sand, and silt environments. Across the Ledge ascidians dominate, followed by a diverse range of sponges, crinoids, anemones, sea stars, bryozoans, and algae. This report describes these environments and the organisms found within them. It makes use of a hydrodynamic model both for describing the environment and for predictive modeling of habitat distributions.