Biodiversity Strategy - Gosford City Council - NSW Government

The saltmarshes merge upwards into supratidal swamp woodlands. Close to the marsh
Casuarina glauca dominate together with Melaleuca quinquenervia. Behind this zone
Eucalyptus robust communities occur. These woodlands are important as nutrient sinks and as
buffers between intertidal wetlands and the hinterland of their catchments.
Saltmarshes are also highly productive environments (Freewater 2004) although specific
information on details such as energy pathways and the export of detritus to adjacent habitats is
limited. They support a variety of invertebrates, including crustaceans, molluscs, polychaetes
and insects, which provide prey items for a variety of fish that exploit the habitat at high tide.
During Spring tides it is estimated that the abundance of crab larvae released is greater than
2000 m-3 of water (Mazumder 2004). This larva is believed to be a significant contribution to the
estuarine food chain, supplementing the nutritional requirements of estuarine fish. Many of the
invertebrate species found among saltmarhes also occur in mangrove and seagrass habitats.
Council is currently developing a research program to examine the role and importance of this
habitat in the seeding of other habitats in Brisbane Water. The results of this project will be
reported in the Brisbane Water Estuary Processes Study (see section on Brisbane Water
below). Saltmarsh are also used by a large variety of birds for feeding, roosting and/or breeding
and are critical habitat for many migratory species.
Figure 6.3 Saltmarsh dominated by Sarcocornia quinqueflora at Davistown on Brisbane Water (Peter
Freewater)
In the estuaries of Gosford, the frontal levees of saltmarshes are typically dominated by
Sporobolus viginicus, but where drift litter accumulates, Suaeda australis, Tetragonia
tetragonioides and Sesuvium portulacastrum can also be abundant. Casuarina glauca is found
higher on the levees. Sarcocornia quinqueflora occurs in the depression landward of the levee,
together with Triglochin striata and Samolus repens, in the wetter patches. Dense rush, Juncus
kraussii, or sedge, Baumea juncea, comprise the mid-marsh community. Fringing the pools are
Phragmites australis, Schoenoplectus litoralis and Schoenoplectus validus, while Ruppia and
the alga Lampromthamnion papulosum may be abundant within the pools. Scattered through
Biodiversity - Technical Report Page 133