 Shapwick Heath, part of the Avalon Marshes in the Somerset Levels Wetlands, and managed as a national nature reserve by Natural England, is a former raised bog lying in the basin of the River Brue.The site supports a diverse community of terrestrial and aquatic invertebrates.National rarities are the Greater Silver Diving Beetle ("Hydrophilus piceus") and the
Lesser Silver Diving Beetle ("Hydrochara caraboides") which is now confined nationally to the Brue Basin Peat Moors.