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
purple wrasse Notolabrus fucicola (Edmunds et al. 2010b). Other fish species include the
banded morwong Cheilodactylus spectabilis, sea sweep Scorpis aequipinnis, Maori wrasse
Ophthalmolepis lineolata, one-spot puller Chromis hypsilepis and white-ear damselfish
Parma microlepis (Parks Victoria 2003). The eastern blue grouper Achoerodus viridis is also
a prominent species, but present in low numbers (Parks Victoria 2003).
Point Hicks MNP provides important feeding and roosting habitat for several threatened bird
species such as the hooded plover Thinornis rubricollis, little egret Egretta garzetta and fairy
tern Sternula nereis which are listed under the Flora and Fauna Guarantee (FFG) Act
(1998). The latter two are regarded as endangered. The MNP protects feeding areas for
species of national environmental significance under the Commonwealth Environment
Protection and Biodiversity Conservation (EPBC) Act (1999) and species that are listed
under the Japan–Australia Migratory Bird Agreement (JAMBA) and the China–Australia
Migratory Bird Agreement (CAMBA, Parks Victoria 2006f). The conservation listed southern
right Eubalaena australis and humpback whale Megaptera novaeangliae, killer whale
Orcinus orca and whale shark Rhincodon typus use the MNP waters. The leopard seal
Hydrurga leptonyx have been observed in the waters in and around the MNP. Although not
recorded the leatherback turtle Dermochelys coriacea probably also occurs in the MNP.
Eleven species of marine flora and fauna are believed to be at their eastern or western
distributional limits within the MNP.
Serious threats to the Point Hicks MNP include limited ecological knowledge of important
processes. Invasive marine pests from commercial and recreational boats; poaching of
abalone; and climate change all pose serious threats to the integrity of the MNP (Carey et al.
2007b). Measures to address or minimise these threats form part of the management plan
for Point Hicks MNP (Parks Victoria 2006f). Ongoing intertidal and subtidal reef monitoring,
and specific research aims to increase ecological knowledge about the natural values of,
and threats to Point Hicks MNP.
2.3.1 PHYSICAL PARAMETERS & PROCESSES
Point Hicks MNP is 3810 hectares in size which makes it the 5th largest of the 24 Marine
National Parks or Sanctuaries in Victoria (Table 14, Figure 17). Point Hicks promontory is
granite with a wide rocky and bouldery shore, which includes some metamorphic outcrops
west of the lighthouse (Bird 1993). Sandy beaches flank the headland backed by extensive
dunes (Figure 18). The seabed has a relatively steep gradient with reef descending into
deeper water relatively close to shore (Ball and Blake 2007). The subtidal reef consists of
granite slopes, boulders and outcrops (Williams et al. 2007). The seafloor of the park drops
away rapidly to 88 metres in depth (Holmes et al. 2007a). Greater than 80% of the MNP is
>20 m depth. Prevailing winds and swells are generally from the south-west and north-east
(Parks Victoria 2006f). Most of the subtidal reef in Point Hicks MNP is highly exposed to
westerly swell and seas (Williams et al. 2007). The coastline is influenced by high energy
waves and twice daily tides. Tidal variation is 0.9 metres for spring tides and 0.6 metres for
neap tides (Plummer et al. 2003). Surface water temperatures average 19° C in the summer
and 14 °C in the winter. The MNP is influenced by both cool southern waters and the warm
East Australian Current. The continental slope is quite close and cold-water upwellings are
frequent (Williams et al. 2007). These upwellings provide nutrients to the inshore
ecosystems, contributing to high productivity (Williams et al. 2007). No estuaries or
intermittent creeks run directly into the park (Table 14).
45