Terms of Reference

National Aquatic Invasive Species Screening-Level Risk Assessment for Eight Crayfish Species

National Science Response Process – National Capital Region

October 5 - 6, 2021
Virtual Meeting

Co-chairs: Lisa Setterington and Justin Shead

Context

Several species of crayfish are imported and/or moved within Canada each year through the aquarium, food, and live bait trades. The federal-provincial-territorial Canadian Council of Fisheries and Aquaculture Ministers’ National Aquatic Invasive Species Committee (NAISC) and Fisheries and Oceans Canada (DFO)’s Aquatic Ecosystems sector’s Aquatic Invasive Species National Core Program have requested scientific advice about the risk posed by Marbled Crayfish to Canada due to its parthenogenic life history characteristics and invasion elsewhere. Other crayfish species have been identified as invasive to Canada, including the Rusty Crayfish and Red Swamp Crayfish. As such, to better understand the ecological risk posed by non‑indigenous crayfish species in Canada, a screening-level risk assessment is needed. A screening-level risk assessment  provides relatively fast advice, based on the best available information, and can be used to provide a relative risk score (higher risk to lower risk). Given broad biogeographical differences across Canadian freshwater ecosystems that could affect invasion success and/or impacts of non-indigenous crayfish species, risk assessments need to be conducted at a suitable spatial scale, such as freshwater ecoregions.

Fisheries and Oceans Canada’s Ecosystems and Oceans Science (EOS) sector previously developed the Canadian Marine Invasive Screening Tool (CMIST) (DFO 2015) to facilitate biological screening-level risk assessments. Although developed for marine species CMIST has successfully been applied to freshwater ones as well (DFO 2017). While the tool is accessible for use by managers and scientists alike, EOS will be using CMIST to conduct this risk assessment in response to NAISC’s formal request for science support. The risk assessment and subsequent science response arising from this process may inform management actions, including early detection, response planning, and/or regulatory and policy measures aimed at mitigating potential risk posed by invasive crayfish to Canadian freshwater ecosystems.

Objectives

The specific objectives of this review are to:

1. Conduct a screening level risk assessment for Marbled, Red Swamp, White River, Rusty, Spinycheek, Virile, Allegheny, and American Signal crayfishes, all of which are non-indigenous to some parts of Canada, using the 21 freshwater ecoregion classifications.
2. Based on the output of the screening-level risk assessment, identify non-indigenous crayfish species that pose a higher risk to Canada and the freshwater ecoregions.
3. Identify data gaps and sources of uncertainty.

Expected Publications

• Science Response
• Proceedings

Expected Participation

• Fisheries and Oceans Canada
• Provinces and Territories
• Academia

References

• DFO. 2015. Marine Screening-Level Risk Assessment Protocol for Marine Non-Indigenous Species. DFO Can. Sci. Advis. Sec. Sci. Advis. Rep. 2015/044.
• DFO. 2017. Screening of the Pacific Fishery Regulations (PFR) Schedule VIII Species for Risk of Invasiveness. DFO Can. Sci. Advis. Sec. Sci. Resp. 2017/040.