Aquatic invasive species prevention

Learn how we’re preventing the introduction and spread of aquatic invasive species and what you can do to help.

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Reducing risks

Aquatic invasive species can be introduced accidentally or intentionally into Canadian waters by human activities. They can become established in our waters and spread rapidly when they don’t face effective natural predators or competitors. In recent years, introductions and spread of aquatic invasive species have been much more rapid due to increased international shipping.

Prevention is the most effective method of dealing with the problem of aquatic invasive species. The most effective approach is to manage the pathways through which aquatic invasive species enter and spread in our waters.

Fisheries and Oceans Canada collaborates with partners to prevent the introduction, establishment, and spread of aquatic invasive species in Canadian waters.

What you can do to help

Everyone using aquatic habitats or handling aquatic organisms can help prevent their introduction and limit their spread before they become a bigger problem.

General measures for preventing aquatic invasive species include:

Bait bucket with live bait.

Bait bucket with live bait.

Construction projects near water.

Construction projects near water.

Waterbodies connected by water diversions.

Waterbodies connected by water diversions.

Waterbodies connected by canals.

Waterbodies connected by canals.

Zebra mussels on a pontoon boat frame.

Zebra mussels on a pontoon boat frame.

International shipping in Vancouver.

International shipping in Vancouver.

Pathways of introduction and spread

Communities can prevent the introduction and spread of aquatic invasive species by paying careful attention in several areas.

Recreational boating

Recreational boating

Recreational boating can lead to biological fouling when organisms, especially invertebrates, attach to hulls and other submerged areas of vessels. These small communities travel with the vessel to new areas, where they can fall off or dislodge and become invasive.

To prevent the introduction and spread of aquatic invasive species from recreational boating:

  • inspect your recreational boating equipment, including:
    • boat
    • motor
    • anchor
    • trailer
    • equipment
  • clean all equipment used in marine environments with freshwater, or spray them with pure vinegar
  • if you find any fouling plants and animals:
    • remove them
    • dispose of them far from the water, in an appropriate compost or garbage bin
  • drain water from your motor, bilge and wells on land
  • let equipment dry completely before entering another water body when possible
  • use environment-friendly anti-fouling paint or products on your boat hull
  • ask for information about local aquatic invasive species issues at the public wharf or marina you visit

For more information

Recreational fishing

Recreational fishing

Aquatic invasive species are introduced and spread when they’re intentionally introduced for recreational fishing purposes. These fish can easily harm the local ecosystem because they often have no local predators and compete with other fish.

Non-native fish that were introduced for recreational fishing purposes and caused significant local damage include:

  • walleye
  • yellow perch
  • smallmouth bass

To prevent the introduction and spread of aquatic invasive species when engaging in recreational fishing:

  • never transfer live fish from one lake to another
  • contact us and report any aquatic invasive species you catch
  • learn about the native species in each lake by consulting with:
    • local fishing groups
    • the provincial or territorial government
    • Fisheries and Oceans Canada
  • obtain authorization from an introduction and transfers committee before introducing any fish into a lake for fishing purposes
Diving and other watersports

Diving and other watersports

Many aquatic invasive species can attach themselves to water sports equipment. To prevent their introduction and spread, make sure to clean, drain and dry your equipment after every use.

Bait

Bait

Baitfish.

Baitfish.

Bait is often used to catch larger fish in commercial and recreational fishing. Using live bait can facilitate the spread of some invasive species. Young Asian carps can easily be mistaken for local minnows.

To prevent the introduction and spread of aquatic invasive species with bait:

  • use non-living bait
  • never release bait into one area if it was caught in another water body

For more information

Aquariums and water gardens

Aquariums and water gardens

Many species used in the aquarium industry are not native to Canada. These species may lead to the introduction and spread of aquatic invasive species when:

  • they escape
  • their owners intentionally release them

To prevent aquatic invasive species, use native species in your water gardens or aquariums.

For more information

Cultural release

Cultural release

Some cultural traditions promote the release of live fish. However, this fish could be non-native and considered invasive in the water body.

Before releasing live fish for cultural reasons:

For more information

Industry and commerce action

Industry and commerce can prevent the spread of aquatic invasive species through several areas.

Shipping

Shipping

Shipping vessels can carry aquatic invasive species in their cargo, ballast water or on their hulls. To prevent the introduction and spread of aquatic invasive species when shipping:

For more information

Aquaculture

Aquaculture

Fish, crustaceans, algae or shellfish grown in an aquaculture facility aren’t always native to the watercourse. Aquaculture facilities may introduce and spread aquatic invasive species to local habitats when:

  • non-native species escape and establish a local population
  • a facility's infrastructure encourages and contributes to biofouling problems

To prevent introduction and spread of aquatic invasive species from aquaculture:

  • keep aquaculture cages clean
  • consult Fisheries and Oceans Canada and your province before introducing a farmed animal for aquaculture purposes
Live food market

Live food market

Aquatic invasive species can be introduced through the live food market. Live fish kept in a market may escape and enter our waters.

To prevent introduction and spread through the live food market:

  • make sure the fish is well identified
  • beware of the sale of Asian carps

For more information

Canals and water diversions

Canals and water diversions

Irrigation canals and other watercourse diversions can connect water bodies, which allow aquatic invasive species to move between locations.

To prevent aquatic invasive species around canals and water diversions:

  • monitor access to the canals
  • report any identified aquatic invasive species
  • consult our projects near water guide prior to any project
Construction in aquatic environments

Construction in aquatic environments

Aquatic invasive species are introduced to an environment during marine construction, such as building and installation of:

  • docks
  • platforms
  • bulkheads
  • breakwaters
  • artificial reefs

They are introduced and spread through transporting sands and sediments and using contaminated construction equipment. Heavy machinery, such as harvesters and dredges, can spread aquatic invasive species if the equipment is not properly cleaned between projects.

To prevent aquatic invasive species during construction in aquatic environments:

  • consult our projects near water guide before starting any project
  • remove aquatic plants and animals before moving vehicles or equipment from a water source
  • ensure all machinery arrives on site in a clean condition

Don't let it loose

Plants and animals that are not native to Canada can become aquatic invasive species if they are released into our waters. These aquatic invasive species can harm our environment, economy and society.

Under the federal Aquatic Invasive Species Regulations, it is illegal to introduce an aquatic species into a body of water where it is not native, unless authorized under federal, provincial or territorial law.

You can help prevent the introduction and spread of aquatic invasive species. Never release aquarium pets, water garden plants, live food (e.g., fish, crabs, shellfish) or live bait into rivers, streams, lakes, ponds, storm sewers or into the ocean. Sport fish may only be released back into the waters from which they were caught (i.e., catch-and-release) and never moved from one body of water to another.

Releasing any organism into any body of water can start an invasion, but you can stop it. It is illegal everywhere in Canada to introduce any organism into a body of water. Stop aquatic invasive species: don't let it loose.

Pets and plants from aquariums, ponds, or water gardens

Pets and plants from aquariums, ponds, or water gardens

Many animals and plants sold for aquariums and water gardens are not native to Canada. Some owners think that releasing a pet that becomes too large, too difficult to care for or that they no longer want is the most compassionate thing to do. This is not true.

Domestic pets generally do not have the survival skills to live beyond their tank or pond. They can starve to death or may be eaten by predators in the wild. Or in some cases, they may survive, reproduce and spread, becoming aquatic invasive species. Even if your pet is native to the local environment, it should never be released, as it may be carrying diseases or parasites. Small pieces or seeds from water garden plants can also thrive and cause an invasion if released.

What should you do instead?

Be a responsible pet and plant owner and C.A.R.E.:
Contact

  • Ask a friend or someone else if they can adopt your pet. Using social media, community lists or online classified ads may be helpful
  • Contact the pet store or place where you purchased your pet to see if they can take it back
  • Research other places that may be able to provide a new home for your pet, such as animal shelters, animal sanctuaries, humane societies, science centers, zoos, aquariums, schools or community organizations
  • Learn about aquatic invasive species in your region. If you have a pet or plant that may be of concern, contact your provincial/territorial government for assistance

Act responsibly

  • Research pets and plants before buying or adopting. Know how large they will get, how long they will live and how much work they entail. Make sure you are willing to fully commit to their lifetime of care. If you see potential issues in caring for them long-term, consider an alternative
  • Know what pets and plants are legal to own. Only buy them from retailers whose species are properly labeled, especially when buying online
  • When gardening, select plants that are native to your region. They will be more likely to thrive and are better for local bees, butterflies, reptiles, amphibians and birds
  • Ensure water gardens and ponds are contained with no chance of any species or water escaping into other waterbodies
  • Ensure any water released from aquariums, ponds or water gardens is done on land and away from household drains, sewers or other bodies of water

Report

End ownership

  • As a last resort, contact a qualified veterinarian to euthanize your pet in a humane manner. This is far kinder than letting it starve to death in the wild or destroy the homes of native species
  • If your pet dies, don't flush it down the toilet. You should bury it instead so it can't spread diseases
  • Dry and freeze non-native plants in tightly sealed bags before throwing them in the trash. Do not compost them
Live food

Live food

Some people intentionally release live food (e.g., fish, crabs, shellfish) from grocery stores or fish markets into the wild as an act of compassion or mercy. This can be harmful to both the released animal (which may not survive in the new environment) or to native species if it survives and becomes invasive. For example, Northern Snakehead may have established its first invasive population in North America through a mercy release.

What should you do instead?

  • Ensure all of the food you purchase is dead before leaving the store
  • If you practice compassion or mercy release for religious or cultural reasons, explore alternative methods, such as volunteering with wildlife sanctuaries that release animals back into their natural environment
  • Always obtain authorization from your provincial or territorial Introductions and Transfers Committee before moving any plants or animals, including importing into Canada, transporting between provinces and territories or transferring from one waterbody to another
Live bait

Live bait

Live bait is often used to catch larger fish in commercial and recreational fishing. Anglers that use live bait should never dump it or the contents of a bait bucket into a waterbody when they are done fishing, as this can lead to the introduction of aquatic invasive species, pathogens or diseases.

What should you do instead?

  • Use artificial bait as a safer alternative when fishing. Remember, even dead or frozen bait can carry diseases
  • Always buy bait from dealers and follow provincial and territorial regulations regarding bait use
  • Regulations on the movement of live bait vary between provinces and territories. Always check the regulations in your region before moving live bait from one waterbody to another
  • Dispose of unused bait, dead fish, fish parts and water or debris from bait buckets in a secure trash area at least 30 metres away from the shore before leaving a waterbody
Sport fish

Sport fish

Deliberately releasing sport fish without authorization in new waterbodies to create angling opportunities is illegal. Sport fish are often large, predatory or generalist feeders. This means they can have widespread negative impacts on a variety of native species. Even species that are native in some parts of Canada can become invasive beyond their natural range.

Some non-native fish that have been illegally moved within Canada for recreational fishing purposes and have caused significant damage include:

These species are all listed in the federal Aquatic Invasive Species Regulations .

What should you do instead?

  • Never transfer sport fish from one waterbody to another
  • Always obtain authorization from your provincial or territorial Introductions and Transfers Committee before moving any plants and animals, including importing into Canada, transporting between provinces and territories or moving from one waterbody to another
  • Report sightings of aquatic invasive species to  Fisheries and Oceans Canada or your provincial/territorial government 
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