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
2.4 Cape Howe MNP – Twofold Shelf Bioregion
Cape Howe is one of three Marine National Parks in the Twofold Shelf bioregion, which also
contains one other MPA, Beware Reef Marine Sanctuary, and Gippsland Lakes and Cape
Conran Coastal Parks (Figure 2). Cape Howe MNP is approximately 15 km east of
Mallacoota. It extends offshore from high water mark to the seaward limit of Victoria’s
coastal waters. It borders 4.8 km of coastline from approximately 1 km east of Telegraph
Point and Gabo Island to the New South Wales border, excluding a section of coast and sea
around Iron Prince (Figure 30 and 31). It is Victoria’s most easterly MNP abutting Cape
Howe Wilderness Zone of Croajingolong National Park, one of only three wilderness zones
on the Victorian coast (Parks Victoria 2006c).
Aboriginal tradition indicates that the park is part of the Country of the Bidwell people and
that other Aboriginal people, including the Yuin Nation, also have an association with the
coastal region of this area (Parks Victoria 2006c).
Important natural values of Cape Howe MNP are its diversity of habitats including long sandy
beaches, intertidal reef along its eastern shore, shallow and deep subtidal reefs, extensive
subtidal soft sediment, and expansive areas of deep open water (Parks Victoria 2006c). Its
rocky reefs have a complex structure, including eroded low-profile sandstone reef and highprofile
granite reef (Carey et al. 2007b). The shallow subtidal reef is dominated by a mixture
of crayweed Phyllospora comosa and bull kelp Durvillaea potatorum, the reef further
offshore tends to be dominated by P. comosa (Ball and Blake 2007; Edmunds et al. 2010b).
On these reefs the herbivorous sea urchin Centrostephanus rodgersii, can remove all erect
algae to create ‘urchin barrens’ (Williams et al. 2007). Common invertebrates include the
blacklip abalone Haliotis rubra, the warrener Turbo undulatus and another turban shell
Astralium tentoriformis (Williams et al. 2007; Edmunds et al. 2010b). Common fish are
herring cale Odax cyanomelas, the leatherjacket Meuschenia freycineti, striped mado
Atypichthys strigatus, banded morwong Cheilodactylus spectabilis and the damselfishes
Parma microlepis and Chromis hypsilepis (Williams et al. 2007; Edmunds et al. 2010b). Its
deep (30 to 50m) sandstone reefs are heavily covered with a diverse array of sponges,
ascidians and gorgonians (Carey et al. 2007b; Holmes et al. 2007b).
The extensive area of subtidal soft sediments are mainly a fine and medium sand, with a low
carbonate content, which becomes dominated by shells in depths >50 m (Holmes et al.
2007b). Extensive macroalgal beds occur on sediment and sediment covered reef 10 to 40
m depth with Caulerpa dominating in 30 to 40 m. Sponges dominate sediment at depths >40
m, with orange ball sponges Tethya dominant in 40 to 60 m depth (Holmes et al. 2007b).
Crustaceans such as amphipods, cumaceans, isopods and ostracods, and polychaetes are
the dominant infauna in 10 to 20 m depth sediments (Heislers and Parry 2007). Common
fish over sediment and sediment covered reef are yellow scad Trachyurus novaezelandiae,
ocean leatherjacket Nelusetta ayraudi, whiting Sillago, grubfish Parapercis sp. eastern bluespotted
flathead Platycephalus caeruleopunctatus, velvet leatherjacket Meuschenia scaber
and the butterfly perch Caesioperca lepidoptera (Moore et al. 2009). The draughtboard shark
Cephaloscyllium laticeps is also common and can be found down to the deepest depths (105
m) of the MNP (Moore et al. 2009).
Cape Howe MNP has a high diversity of intertidal and shallow subtidal invertebrates
(Edmunds et al. 2005; Carey et al. 2007b). Eastern temperate, southern cosmopolitan and
temperate species co-occur as a result of the mixing of warm eastern and cool southern
waters (Edmunds et al. 2005; Parks Victoria 2006c). Thirty-eight species of marine flora and
fauna are believed to be at their eastern, western or northern distributional limits within the
planning area (O’Hara and Poore 2000).
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