In our sheltered bays and estuaries, low mats of succulent beaded glasswort form complex mosaics with dense swards of Sea rush (Juncus krausii) and Sawsedge (Gahnia filum & Gahnia trifida) sedgelands. These areas support large numbers of molluscs, crustaceans and waterbirds such as Soldier crabs and Black swans. Beautiful but muddy, saltmarsh is best viewed from hard ground such as the North West Bay saltmarsh from Dru Point Track, Margate or the Snug River saltmarsh from the Snug River Track
Within Kingborough our largest areas of saltmarsh are North WestBay (15 ha), Lutregala Marsh in SimpsonsBay, South Bruny (40 ha) and Cloudy Bay Lagoon, South Bruny (51 ha). Small areas of saltmarsh are scattered along the bays of D’Entrecasteaux Channel such as at the mouth of Snug River, Snug and Browns River, Kingston.
Saltmarsh; Beaded glasswort and Coastal sedge
Seagrasses are flowering plants that grow in underwater meadows in bays, estuaries and sheltered shallow parts of the sea, such as in North Wes tBay, between Woodbridge and Gordon, Little Taylors Bay and Great Taylors Bay, South Bruny (Parsons, 2012).
Seagrasses are bio-indicators. They are subject to rapid environmental changes arising from not only natural causes but also human-induced pressures, such as coastal development, toxicant releases, sewage discharges and sediment run-off. Information on the extent and status of seagrass communities support the sustainability of not only native natural environment but also the quality of life of the local people (Mount & Otera, 2011).
(Source: Mount R. E. and K. Otera, 2011, The status of seagrass extent in North West Bay. A technical report for the Kingborough Council by the Blue Wren Group, School of Geography and Environmental Studies, University of Tasmania, Hobart, Tasmania)
Giant kelp or String kelp (Macrocystis pyifera) is the longest and fastest growing marine plant, growing up to 35 metres long. This giant seaweed extends from the seafloor to the surface buoyed by air bladders attached to the leaves. It forms kelp forests that provide shelter and habitat to a high diversity of marine fauna including fish, sea snails, worms, sea urchins, crabs, sea stars, lace corals and sponges. For more information go to http://www.geol.utas.edu.au/kelpwatch//index.html
Kelp forests grow as a narrow band around many of the rocky shoreline areas of Kingborough, such as between Gordon and Nine Pin Point. Though it may seem abundant, it covers only about 770 hectares of the coastline of Tasmania which represents a dramatic decline over the past 70 years. Possible reasons for the decline include increasing sea temperature, ‘sea urchin barrens’ created by introduced sea urchin grazing, pollution and competition by the introduced Japanese kelp (KelpWatch , 2004).