Biofouling - the threat to Australia

All vessels entering Australian waters, regardless of their size or frequency of visits, pose a biofouling risk to Australia’s marine biosecurity.

Australian coastal industries (including seafood, fishing and tourism) and the marine environment are at threat from the introduction of invasive marine pests into Australian waters.

Over 250 marine species have been introduced into Australian waters by vessels of all types, from yachts to commercial ships. Of these, with up to 75 per cent are likely to have arrived as biofouling organisms attached to the external and internal surfaces of vessels. Once established, marine pests are virtually impossible to eradicate. Like cane toads and rabbits, they multiply rapidly, force out native species and devastate the environment and the industries that rely on that environment.

Image courtesy of Bayview Slipway Marine Service

What are the risks to Australia from biofouling?

All vessels are prone to biofouling, including commercial, nontrading vessels (such as barges, dredges and tugs), fishing and recreational vessels. Submerged movable structures, such as oil rigs, are also prone to biofouling and pose a risk when moved to new locations.

With its large coastline and an average of 12 500 international vessel visits a year, Australia is highly exposed to the risk of invasive species from other regions being introduced into its coastal waters. If these species successfully establish viable populations, they can quickly spread around the coastline, devastating local marine ecosystems and threatening Australia’s coastal industries. The consequences are significant and include the following:

Damage to the marine environment

Invasive pests compete for space and food supply, resulting in changes to the native marine habitat that may threaten the local food chain. For example, the destruction of native seagrass beds may also affect the abundance of fish and other species that previously sheltered among the seagrass. Such changes may also reduce the area’s recreational and/or cultural value to the community.

Depletion of fishing grounds and aquaculture stock

Some invasive pests are voracious predators, capable of depleting aquaculture stock or fishing grounds. Reduced produce availability may increase the cost of seafood and reduce the viability of the fishing, aquaculture and seafood industries.

Reducing the attractiveness of coastal areas

Some pests can extensively damage the aesthetic value of shorelines and coastal areas, affecting recreational pursuits and tourism. Common examples include fouling of coastal structures, overabundance of sharp or unattractive shells and erosion resulting from crabs burrowing into shorelines.

Damaging marine and industrial infrastructure

Introduced species can settle on marine structures such as jetties, industrial water intake pipes or longlines used in aquaculture, and potentially cause damage. The costs of repairing or replacing these structures can be significant and present an ongoing maintenance expense.

Reducing vessel performance

A build-up of marine biofouling on vessel hulls affects vessel speed, which can impact fuel efficiencies. Although antifouling coating can help prevent biofouling, if the coating is not applied correctly or reapplied in a timely manner, its effectiveness can be greatly reduced. Biofouling can also clog a vessel’s internal waterpipes, causing engine damage, ineffective firefighting ability and damage to other water-reliant systems. Reduced vessel performance increases operating costs, which in turn increases freight costs.

Potentially causing serious human illnesses/poisoning

Invasive marine pests can accumulate or carry harmful organisms including toxic algae, bacteria and flukes. Consumption of affected shellfish or crustaceans can lead to serious illness. Apart from human health consequences, a loss of public confidence in local supply can significantly impact Australia’s seafood industries.

Image courtesy of CSIRO Marine & Atmospheric Research

What is Australia doing about the risks posed by marine pests arriving as biofouling?

To minimise the risk of marine pests arriving in Australian waters, the Australian Government is proposing new regulations that will require vessels entering Australian waters to be free of quarantinable biofouling species.

The regulations will apply to every vessel arriving in Australian waters, recognising that all vessels pose a biofouling risk irrespective of size, purpose or origin.

The proposed Australian biofouling regulations will help protect our marine environment and industries from invasive marine pests. Vessel operators will be encouraged to self-assess their vessel’s risk profile and actively manage for biofouling before arriving in Australian waters.

The risk from biofouling is also being addressed internationally. Australia is working with other nations through the International Maritime Organization to develop voluntary international biofouling management guidelines.

For more information visit the marine pests website.