Meet the creatures of Port Phillip Bay
Written by Annika Withers, MMF Volunteer
In honour of National Biodiversity Month, let’s dive into our own backyard and explore some of the amazing marine biodiversity that we have in Port Phillip Bay.
Australia’s oceans are amongst the most biodiverse in the world, and the rich, varied habitats of the Bay are home to a huge array of plants and animals. The Bay is of significant social, economic, and environmental value to Victoria, hosting around 300 species of fish, at least 200 species of seaweed, hundreds of species of molluscs and crustaceans, many marine mammals, and more, including at least 85 protected resident protected species.
Marine biodiversity is critical for sustaining our ocean’s resources. It is important that we learn about diversity and how to protect it. Let’s dive a little bit deeper into the biodiversity of Port Phillip Bay by taking a look at just a handful of the amazing creatures that live in and visit the waters of the Bay.
Burrunan dolphin (Tursiops australis)
Burrunan dolphins have distinct tri-colouration with a darker grey on the dorsal side, lighter grey along the flanks extending over the eye, and a whiter colour on the underbelly. Formally described as a separate species in 2011, they are closely related to the bottlenose dolphin. ‘Burrunan’ is the Aboriginal name given to the dolphins of Port Phillip Bay by the Kulin nation, meaning “name of a large sea fish of the porpoise kind”. The Bay hosts a population of only 120 Burrunan dolphins.
Habitat: Victoria, Tasmania, and Esperance, WA (confirmed), and South Australia (unconfirmed)
Size: 2.3-2.8m
Conservation status: Critically endangered (VFFG Act 1988)
Australian fur seal (Arctocephalus pusillus doriferus)
The Australian fur seal is an eared seal (otariid) and the largest of fur seals around the world. Males have dark grey-brown fur with thick mane-like hair on the neck, while females are a fawn-grey colour with pale yellow colouring on their throat. They are highly skilled hunters, diving up to 150m deep to capture prey such as fish, squid, and octopus.
Habitat: Rocky islands and pebble beaches of Bass Strait, Tasmania and Southern Victoria
Size: females 50-100kg, males 220-360kg
Conservation status: Least Concern (IUCN).
Humpback whale (Megaptera novaeangliae)
Humpback whales are baleen whales; they have comb-like plates instead of teeth that filter prey from the water. They have a small hump in front of their dorsal fin, and long pectoral fins unique to the species. Humpbacks are known for aerial displays that can be beautiful yet dangerous; if they land on small vessels, the outcome can be catastrophic. Annual migration paths for humpbacks that visit the Bay lead from summer feeding grounds in Antarctica to warmer waters near the equator to breed in winter, which can be some of the longest migration paths of any mammal!
Habitat: Antarctic waters (summer), topical waters (winter), coastal waters (migration)
Size: 11-18m long
Conservation status: Vulnerable (EPBC Act 1999)
Southern right whale (Eubalaena australis)
The Southern right whale is another baleen whale most distinguishable by the white growths on their head known as callosities. These thickened pieces of skin are perfect for individual identification as each whale has a unique arrangement of them. Southern right whales inhabit the waters south of the equator, with the population in Australian waters being genetically distinct to other populations in the southern hemisphere.
Habitat: Antarctic waters (Summer), temperate waters (winter), coastal waters (migration)
Size: Up to 17m
Conservation status: Endangered (EPBC Act 1999)
Drone Image of Nessie and calf: Photo Credit: Emily Gregory GABRWS (image taken under permit M26085-10.)
Orca (Orcinus orca)
The Orca, or ‘Killer Whale’, is classified as a toothed whale, and is therefore not actually a whale at all! Dolphins are classed as ‘toothed whales’ in the cetacean family tree, and the Orca is in fact the largest of the dolphins. They are easily recognisable by their striking black and white colouration and prominent dorsal fin. Orcas are aptly referred to as Killer Whales; they are apex predators and some of the most efficient ocean hunters, even known to play with their food.
Habitat: All oceans; most abundant in cold waters
Size: Up to 8m
Conservation status: Data deficient (IUCN)
Image credit: Project ORCA
BONUS MMF FAVOURITES
Weedy sea dragon (Phyllopteryx taeniolatus)
The weedy sea dragon is a marine fish and relative of the common seahorse. They have long pipe-like snouts and beautiful colourations, including unique spots on their torso that act like fingerprints. With their seaweed-like appendages and small size they are masters of camouflage. Weedy sea dragons are special in that they are endemic to Australian temperate marine waters, meaning they are found nowhere else in the world but here.
Habitat: Seagrass beds, kelp-covered rocky reefs, depths 1-50m
Size: 30-45cm
Conservation status: Near threatened (IUCN)
Eleven-armed sea star (Coscinasterias calamaria)
The eleven-armed sea star, as the name suggests, is usually found with 11 arms, but can actually be found with anywhere between 7 and 14 of varying lengths. Found in Australia and New Zealand, this sea star is one of the largest occurring in these areas. In order to reproduce, a single eleven-armed sea star splits in half via a process called binary fission and a new individual regenerates from each half. Incredibly, a whole new sea star can grow from just one arm broken off from the individual!
Habitat: Intertidal rocky shores, coastal waters, to depth 150m
Size: Up to 40-50cm in diameter
Conservation status: Not listed
Giant kelp (Macrocystis pyrifera)
Giant kelp are the foundation species of giant kelp marine forests, which are important ecological communities. Towering high and in dense forests they provide a habitat, breeding ground, and food for thousands of marine species. But despite what you might think, kelp is in fact not a plant. Instead, they are extremely large brown algae that look much like plants with blades (leaves), a stipe (stem), a holdfast (root), and the ability to photosynthesise. Giant kelp forests are the first ecological community to be listed as endangered in Australia.
Habitat: Subtidal rocky reef (moderate wave action), to depth 44m
Size: Up to 53m
Conservation status: Endangered (EPBC Act 1999)
If you’re interested in some other websites that will show the biodiversity in your area, around Australia, and globally, here are a few to get you started:
