Rising sea levels, increasing ocean temperatures and growing ocean acidity are just some of the impacts that climate change will have on Victoria’s marine environment. Add introduced marine pests, fishing, ocean outfalls, catchment runoff and coastal development, and you have a nasty cocktail of threats facing our marine life.

Ocean acidification: a direct result of greenhouse gas emissions being absorbed by the oceans. On a large scale, it could be catastrophic for marine life and lead to the collapse of marine ecosystems.

Stormy seas: increasing storm activity and more turbulent ocean waters could affect the growth of phytoplankton and the fish, seals, whales, penguins and other marine life that depend on it. Increased storm and flood activity could wipe out seagrass, beds, mangroves and saltmarshes.

Increased sea temperatures: are already affecting where marine species live. The sea urchins have been able to move further south and are eating their way through kelp forests and seagrass meadows, which are significant habitats for many other marine species.

Rising sea levels: will threaten low-lying coastal areas including nearshore and intertidal habitats but also coastal infrastructure.

Introduced marine pest plants and animals: the carnivorous north pacific seastar has spread throughout Port Phillip Bay, preying on native species. It could spread to other areas along the Victorian coast.

Fishing: has a big impact on marine conservation values, affecting the species being fishes as well as other marine species, communities and ecological processes. For example, fishing that targets particular species can alter population structures, often removing key high-level predators vital to the health of marine ecosystems.

Waste outfalls and catchment runoff: impact on water quality and can cause algal blooms that remove oxygen and result in fish kills. Land based activities contribute up to 80% of all marine pollution and are a major threat to the long-term health of nearshore marine systems.

Coastal development: 85% of Australians live within 50 kilometres of the coast. As the population grows, subdivision and urbanisation of coastal areas is also increasing, resulting in the removal of important habitats.

Shipping: many introduced marine pests have found their way into Port Phillip Bay on ships hulls and in ballast water. Channel dredging can affect water quality and the health of seagrass meadows, while the construction of port infrastructure removes marine habitats.

Oil and gas: seismic testing for oil and gas exploration can impact on marine life, particularly whales

If Victoria is to have a marine environment strong enough to withstand these threats, we must improve marine and coastal management and protection.