The Otway Marine Bioregion extends from Cape Jaffa in South Australia to Apollo Bay in Victoria and includes the western islands of Bass Strait, such as King Island.


Marine Protected Areas

  • Discovery Bay Marine National Park
  • Merri Marine Sanctuary
  • Twelve Apostles Marine National Park
  • The Arches Marine Sanctuary
  • Cape Bridgewater Protected Seal Breeding Colony
  • Deen Maar (Lady Julia Percy Island) Protected Seal Breeding Colony
  • Logan’s Beach Exclusion Zone – Southern Right Whales


Significant areas of Otway

  • Bridgewater Bay
  • Portland Bay and Deen Maar
  • Port Campbell
  • Cape Otway

Caption: Giant Kelp (Macrocystis pyrifera) 📷 Kade Mills
  • Cold ocean waters originating from the Southern Ocean
  • Large, powerful waves
  • Seafloor gradient drops away steeply as you move offshore
  • Slow to moderate ocean currents
  • Nutrient-rich waters. Ocean nutrients ‘well-up’ from deep water to the surface at the edge of the continental shelf in an oceanographic event known as the Bonney Upwelling
  • Dominance of leathery Bull Kelp (Durvillaea potatorum) on shallower rocky reefs
  • Offshore reefs are dominated by Giant Kelp (Macrocystis pyrifera) and Crayweed (Phyllospora comosa)
  • The region is the westward range limit for a number of key seaweed species
  • Intertidal animals found west of Cape Otway show significant similarities to intertidal animals at King Island and south-east South Australia

Caption: Sea Nymph (Amphibolis antarctica) 📷 Nicole Mertens
  • The region is a feeding aggregation area for Pygmy Blue Whales (Balaenoptera musculus brevicauda), drawn to the swarms of krill that benefit from the nutrient-rich waters
  • The Lawrence Rocks near Portland support the largest colony of Australasian Gannets (Morus serrator) in Australia
  • Deen Maar Island supports one of the largest breeding colonies of Australian Fur Seals (Arctocephalus pusillus doriferus) in Australia
  • The imposing undersea ‘wall’ in the Port Campbell area, where the seafloor plunges 20m over a short distance
  • The extensive seagrass meadows of Sea Nymph/Wireweed (Amphibolis antartica) within Portland Bay
  • The Warrnambool to Port Fairy area is a significant calving and nursery area for Southern Right Whales (Eubalaena australis)