parks victoria technical series marine natural values study vol 2 ...

Parks Victoria Technical Series No. 79
Flinders and Twofold Shelf Bioregions Marine Natural Values Study
2.1.2 MARINE HABITAT DISTRIBUTION
Mapping of habitats is important for understanding and communicating the distribution of
natural values within Marine National Parks and Sanctuaries, particularly as the marine
environment is not as easily visualised as the terrestrial environment (Parks Victoria 2003).
For management purposes, knowledge of the distribution and extent of habitats is required
to more effectively target management activities, including emergency response, monitoring
and research. Mapping of marine habitats provides a baseline inventory, allows the
identification of suitable monitoring sites and possible tracking of environmental change, as
well as identifying areas vulnerable to particular threats or suitable for recreational activities.
The main habitats present in Wilsons Promontory MNP include some intertidal soft sediment
and reef, extensive subtidal soft sediment and reef, and open ocean (Figure 8). LiDAR
mapping of the coastline has been done but it is limited by depth to shallow habitats in
Oberon and Norman Bays on the west side of Wilsons Promontory MNP, in Waterloo Bay on
the east side of the park and some areas around the tip of Wilsons Promontory (Figure 6).
This represents a very small proportion of the park, the surveys found heavy reef with some
low profile reef. No modelling of habitats has been done, so unlike other parks, we do not
have a good understanding of the distribution and extent of basic habitats within the MNP.
The majority of the Wilsons Promontory MNP substrate has been mapped as soft sediment,
but this may change with additional more detailed acoustic mapping. The subtidal sand
plains extend to at least 20 m depth and are composed of both coarse and fine calcarenite
sediments Plummer et al. (2003).
Figure 7. Crayweed Phyllospora comosa in Wilsons Promontory Marine National Park
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