State of the Reef Report 2005: Seagrasses

Abstract

Seagrasses are flowering plants and occur in the coastal, estuarine, reef and deepwater habitats of the Great Barrier Reef. Fifteen of the sixty known species of seagrass worldwide occur in Queensland, most of which are widespread. Seagrasses are commonly found in shallow waters less than 10m deep. However, recent surveys have mapped seagrasses down to a depth of 60m. At these depths, the Halophila species are predominant. Recent estimates suggest that seagrass beds cover approximately 13% of the Great Barrier Reef World Heritage Area (GBRWHA), indicating the presence of some 6,000 square kilometres of shallow seagrass habitat and a further 40,000 square kilometres of deepwater seagrass habitat in the Great Barrier Reef.