Invasive fish species

Invasive fish species can threaten native species, impact water quality and reduce recreational use of waterbodies.

Introduction

Invasive fish are non-native species introduced into aquatic ecosystems. These species:

  • have high reproductive abilities
  • compete with native species for food and resources
  • disrupt ecosystems, threatening native plant, fish and insect populations

Invasive fish species disrupt overall biological diversity of ecosystems, and impact recreational fisheries. All species found on this page have been detected in Alberta.

Common invasive fish species

This prohibited non-native fish outcompetes native species for resources and poses a risk to human health.
These common ornamental fish can pose significant harm to aquatic ecosystems when released into the wild.
This prohibited non-native fish outcompetes native species for food and resources through its high reproductive and competitive abilities.
This introduced fish disrupts aquatic ecosystems and poses potential threats to native fish.
This recently introduced fish has potential to disrupt aquatic ecosystems and pose threats to native fish.

Invasive fish response

As invasive fish species become established across the province, it is important for organizations to work together to prevent the spread, minimize impacts and use control methods to eradicate them where possible. Rotenone treatments are used by the Alberta government and partners due to the high likelihood of success in eliminating undesirable fish species from compromised waterbodies. Organizations, such as municipalities, can also perform select treatments to eradicate invasive fish species. Here is what you need to know to prepare for doing a treatment:

  • Mandatory reporting of aquatic invasive species

    As of July 2015, there are 25 prohibited fish species under the Fisheries (Alberta) Act. It is mandatory to report any of the 52 prohibited species listed in the Fisheries(Alberta) Act within 14 days of finding them to provide the best chance of response success. There are 3 ways to report invasive species:

  • Meeting the criteria for treatment

    Regardless of an unintentional or intentional release, if there is evidence that invasive fish have established, response needs to be considered.

    Response for fish included on the list of 52 prohibited species under the Fisheries(Alberta) Act will be priority for Alberta Environment and Protected Areas.

    For fish species (such as goldfish, koi or Prussian carp) that are not listed in provincial regulations, Alberta Environment and Protected Areas can help support response treatments by guiding the approval process and support the development of response plans in conjunction with the organization or municipality. Legislation supporting treatments for species that are not included in the provincial prohibited species list falls under the federal AIS Regulations, Section 10, which states that any organism that is not indigenous is prohibited to enter water of any kind, unless authorized by provincial or federal law.

  • Public requirements for fish removal using rotenone

    Control of invasive fish is most feasible in isolated ponds. However, once released into flowing connected bodies of water, control efforts are exponentially more complex. Rotenone has been effective in the removal of invasive fish when used on its own, or in conjunction with other methods as compared to only using non-chemical methods (netting, water table fluctuations, electrofishing, etc.).

    To learn more about rotenone, see the Rotenone: Invasive fish control in Alberta storm water management ponds fact sheet.

    Requirements for fish removal using rotenone requires 4 main steps prior to treatment. The following are outlined below:

    1. Special Use Approval (Pesticide (Ministerial) Regulation, Section 9), is required if using/applying/storing a pesticide in or within 30 m of an “open body of water” (refer to definition below) unless following the Environmental Code of Practice for Pesticides.
      • Open Body of Water: as defined under the Pesticide Sales, Handling, Use and Application Regulation, “open body of water” means the bed and shore of an irrigation canal, drainage canal, reservoir, river, stream, creek, lake, marsh or other body of water, but does not include the following:
        • waterworks systems
        • reservoirs, lakes, marshes or other bodies of water that are completely surrounded by private land, that have an area of less than 4 hectares and have no outflow of water beyond the private land
        • reservoirs, lakes, marshes or other bodies of water that are located on public land, that have an area of less than 0.4 hectares, and have no outflow of water
        • irrigation and drainage canals that are completely surrounded by private land and have no outflow beyond the private land
        • roadside ditches
        • wastewater systems
        • storm drainage systems
        • dry streams having a bed and shore averaging 0.5 meters or less in width within the boundaries of the treatment area
        • a constructed water hazard that is located on a golf course and has no outflow of water beyond the golf course boundary
      • The application can be found at Pesticides – Application forms.
    2. A Fish Research Licence (Fisheries (Alberta) Act, Section 12) [ii] is required for anyone (person, agency or institution) whose work involves collecting, holding or sampling fish for inventory, research, educational or promotional purposes in Alberta.
    3. A Deposit of Deleterious Substances Application is required for any work in water that demands a substance to be added to the water that has the potential to degrade or alter the water quality affecting fish or fish habitat, including fish toxicants and pesticides.
      • Deleterious Substance: as defined under the Fisheries (Alberta) Act (Section 34), “deleterious substance” means:
        1. any substance that, if added to any water, would degrade or alter or form part of a process of degradation or alteration of the quality of that water so that it is rendered or is likely to be rendered deleterious to fish or fish habitat or to the use by man of fish that frequent that water, or
        2. any water that contains a substance in such quantity or concentration, or that has been so treated, processed or changed, by heat or other means, from a natural state that it would, if added to any other water, degrade or alter or form part of a process of degradation or alteration of the quality of that water so that it is rendered or is likely to be rendered deleterious to fish or fish habitat or to the use by man of fish that frequent that water.
    4. Acquire certifications or hire a contractor with:
      • appropriate Pesticide Service Registration (under the Pesticide (Ministerial) Regulation, Section 7)
      • appropriate Pesticide Applicator Certification (under the Pesticide (Ministerial) Regulation, Section 3)

Help stop the spread of invasive fish

Report aquatic invasive species:

Learn more about identifying and preventing invasive fish species:

Spread the word about the threats invasive fish pose: