Oriental weather loach

This prohibited non-native fish outcompetes native species for food and resources through its high reproductive and competitive abilities.

Place of origin and introduction to Alberta

Oriental weather loach (Misgurnus anguillicaudatus) is a prohibited non-native fish that can quickly outcompete native species for food and resources through its high reproductive and competitive abilities.

Oriental weather loach is native to East Asia. It has been introduced in North America from the live aquarium trade, commercial food industry, use as live bait, accidental escapes and intentional releases.

While this fish species is not presently found in Alberta, potential introduction of oriental weather loach was recently intercepted by the Canada Border Service Agency (CBSA) when discovered upon import for aquarium retailer distribution.


  • Yellow to brown in colour, with brown markings on backside and silver underside
  • Slender eel-like body
  • Small, narrow mouth lined with up to 10 whisker-like barbels
  • Dark spot on upper caudal fin


  • Single female can lay up to 100,000 eggs in a lifetime
  • Can live up to 13 years


  • Extremely hardy and adaptable – can breathe air if necessary
  • Can tolerate extreme conditions such as desiccation, temperature and starvation
  • Secretes mucous layer around body to aid in survival in drought conditions, allowing for further dispersal over longer distances
  • Outcompete native species by reducing habitat and food, and preying on offspring of other fish species

Current management

  • Oriental weather loach is listed as a prohibited invasive species, making it illegal to import, transport, sell and possess in Alberta.
  • Prevention is the best defence as there are no selective control measures. Available response options are expensive and time consuming. Prevention is prioritized through prohibition of import into Alberta.
  • When feasible, manual removal through netting and angling can be used, but is labour intensive.
  • Pesticide treatment can be done as a last resort but is often only feasible for use in isolated waterbodies without other fish present.

Take action

Never import, purchase or release oriental weather loach into Alberta waterbodies. Penalties for introducing a fish into any waterbody other than where it was found can be up to $100,000 and/or a year in prison. See:

Report sightings of aquatic invasive fish:

By telephone: Aquatic Invasive Species Hotline
1-855-336-BOAT (2628)
Online via mobile or desktop: EDDMapS Alberta App

Report any unlawful activities to:

  • Report-a-Poacher phone line
    1-800-642-3800 (Toll free 24 hours a day, 7 days a week)