parks victoria technical series marine natural values study vol 2 ...
parks victoria technical series marine natural values study vol 2 ...
parks victoria technical series marine natural values study vol 2 ...
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Parks Victoria Technical Series No. 79<br />
Flinders and Twofold Shelf Bioregions Marine Natural Values Study<br />
Intertidal<br />
Soft sediment<br />
There is no intertidal soft sediment habitat in Beware Reef MS.<br />
Reef<br />
Intertidal reef biota is exposed to large changes in physical conditions such as temperature<br />
and desiccation. There is great spatial and temporal variability in the life histories of the<br />
organisms and the environmental processes in reef habitats (Underwood and Chapman<br />
2004). The recruitment of new biota onto the reef, largely from plankton, strongly influences<br />
the ecological patterns for individual species and assemblages. Interactions between biota<br />
on the reef also influence biota distribution. Resources which are often in short supply on<br />
intertidal reefs are space on which to live and food (Underwood and Chapman 2004).<br />
The exposed intertidal reef is a 0.3 hectare gently rounded offshore granite platform, which<br />
is wave-swept in high seas (Parks Victoria 2006a). Thick stands of bull kelp Durvillaea<br />
potatorum dominate the lower intertidal reef, with coralline algae and fleshy green and brown<br />
algae occurring elsewhere (Parks Victoria 2006a). Durvillaea is more abundant along the<br />
exposed southern side of the island (Edmunds et al. 2005).The cunjevoi Pyura stolonifera is<br />
the dominant invertebrate on the intertidal reef (Parks Victoria 2006a). Large barnacles and<br />
mussels cover much of the rock, while other areas are bare (Parks Victoria 2006a).<br />
As noted by Plummer et al. (2003) no specific data on the biota of intertidal reefs are<br />
available for Beware Reef MS.<br />
Subtidal<br />
Soft sediment<br />
Deep subtidal soft sandy sediment is widespread within the MS. No biological surveys have<br />
been undertaken of this community within the sanctuary to date, but it probably supports<br />
numerous polychaetes, isopods, gastropods, euphausiids, ophiuroids, bivalves, amphipods,<br />
cumaceans and cephalopods (Plummer et al. 2003). A trawl survey conducted 10 km west<br />
of the sanctuary indicates that the presence of some species of fish is seasonal. Common<br />
species found included: sparsely spotted stingaree Urolophus paucimaculatus, gurnard<br />
Lepidotrigla spp., flathead Platycephalus spp., common gurnard perch Neosebastes<br />
scorpaenoides, banded stingaree Urolophus cruciatus and school whiting Sillago bassiensis<br />
(Bird & Watson 1993 as reported in Plummer et al. 2003). Numerous shark species were<br />
also found in the survey: swell Cephaloscyllium laticeps, angel Squatina australis, spotted<br />
cat Asymbolus analis, southern saw Pristiophorus nudipinnis, elephant Callorhynchus milii,<br />
gummy Mustelus antarcticus and Port Jackson Heterodontus portusjacksoni sharks.<br />
Newborn pups of gummy sharks inhabit shallow inshore areas and there is some evidence<br />
to suggest that the inshore sandy areas east of Wilsons Promontory, including Beware Reef<br />
MS, may be important feeding areas for gummy shark pups (Plummer et al. 2003).<br />
Reef<br />
Subtidal reefs and the assemblages associated with them are strongly influenced by the<br />
position of the reef, its orientation, slope, depth, exposure and topography (Connell 2007).<br />
These physical parameters influence key physical processes such as light, water flow and<br />
sedimentation, and biological processes such as foraging and recruitment (Connell 2007).<br />
Biotic assemblages of algae and sessile invertebrates can form habitat and food sources for<br />
invertebrates and fish. Shallow (< 15 m) subtidal reefs are known for their high biological<br />
complexity, species diversity and productivity and in addition they have significant economic<br />
value through commercial and recreational fishing (outside of MPAs), diving and other<br />
tourism activities (Power and Boxshall 2007). Shallow subtidal reefs are often dominated by<br />
canopy forming algae. Deep reefs, where light penetration is limited, are often dominated by<br />
large sessile invertebrates such as massive sponges, whip corals, soft corals and colonial<br />
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