Marlborough Sounds Resource Management Plan D Marine - Tasman Bay/Admiralty Bay Collective Characteristics: Mainly Sheltered Turbid, warm waters; open to the sea, but relatively sheltered; limited reef zone and conspicuous marine life generally sparse; sediments off-shore. A. The Physical Environment 1. Form/Geology Relatively narrow near-shore bedrock/cobble reef zone, with sand beaches often located at the heads of bays. Extensive areas of sand/shell in places close to shore, replaced by silts in deeper off-shore areas. 2. Dynamic Features and Processes, Including Climate Generally open to the sea, yet still sheltered from large oceanic swells. 3. Water Moderate sedimentation and turbidity levels. Relatively warm coastal waters derived from the D’Urville current and Tasman Bay. Large tidal range exposing a wide inter-tidal zone at low water. Very strong currents in the vicinity of French Pass, though low to moderate elsewhere. B. The Biological Environment Distinctive Biota, Communities and Habitats Natural Biodiversity, Productivity and Biotic Patterns Notable for a low biomass and diversity of macro-algae which are restricted to a narrow band immediately below low water. Sub-tidal reefs relatively barren, though there is often a high diversity of fish and encusting animals in outer rocky areas compared to other sheltered shores in the Sounds. Key indicator organisms are the barnacle Balanus vestitus east of French Pass, and Stegnaster inflatus which is particularly common in the west. Whangarae Estuary within Croisilles Harbour is relatively unmodified and the only spit formed estuary in the Sounds. C. Potential for Restoration Restoration of riparian habitat. App Two - 66