BIA Victoria - What are marine pests?
What is a marine pest?
How do they affect the native plants and animals?
Marine pests come in all shapes and sizes – giant weeds, seastars, fish, worms, or even tiny single celled organisms. They can affect our native marine life in many different ways:
- Prey on native plants and animals. The northern Pacific seastar is a voracious predator that feeds on native shellfish. Marine pests can also feed on local plants, plankton, fish eggs, crustaceans etc.
- Compete for local food. The Sabella worm is a very successful feeder, filtering the water for plankton and zooplankton. It competes for this floating food with the local plants and animals.
- Dominate an area, taking up all the space and excluding the natives. The fast growing weed Japanese kelp can easily establish in a new area, taking nutrients, light and space from native seagrasses.
Worldwide, introduced marine species are wreaking havoc:
- A small jelly introduced into the Black Sea has caused the collapse of their $250 million a year fishing industry.
- The invasive zebra mussel is costing the US over $1 billion every year in clean up and control.
- The introduced algae, Didymo is rapidly spreading across the South Island of New Zealand and threatening the trout fishing industry – worth millions in tourism.
How can pests affect your boating and fishing?
- Reduce fish numbers
Pests can interrupt natural food chains and change habitats. This can force animals out of their normal breeding and feeding areas, and possibly reduce their numbers. For example, handfish numbers in the Derwent River estuary in Tasmania have been severely depleted because of the northern Pacific seastar that feeds on the handfish eggs. - Boating, anchoring or fishing restriction areas
Some pest infestations can lead to boating or fishing restrictions to stop the pest spreading further. This is happening in Queensland because of invasive mussels and in NSW and South Australia because of the invasive weed Caulerpa taxifolia. - Damage your boat and gear
Pests that stick to the bottom of your boat, like weeds or barnacles, can damage the paint or hull surface. Pests can clog water inlets/outlets and cause the motor to overheat or the internal seawater pipes to close up – it's very expensive to have pipes cleaned and even more expensive if they have to be replaced.
You need to keep your boat and gear clean to make sure you are not spreading invasive marine pests – creating new populations in pristine areas.
Follow the simple cleaning check lists here:
Click here if you moor your boat (yachts, cruisers etc)
Click here for trailer boats, canoes, kayaks and jetskis