Development of a surveillance species list to inform aquatic invasive species management in the Laurentian Great Lakes

In an effort to harmonize multi-jurisdictional surveillance and detection of aquatic invasive species, regional stakeholders have called for the development of a Great Lakes Aquatic Invasive Species Surveillance Framework to identify species that pose a risk to the basin, quantify the relative risk of various pathways of introduction, provide guidance on monitoring protocols for surveillance, and identify priority locations for surveillance based on this pathway assessment. Here, we screen 448 species to develop a surveillance list of 144 species that are relevant for Great Lakes surveillance: are not yet widespread throughout the basin, have a pathway through which they can arrive, are able to establish and are predicted to cause impacts. Using the Great Lakes Aquatic Nonindigenous Species Risk Assessment for consistent assessment across taxa, the surveillance species list consisted of 144 species: 64 plants, 4 algae, 40 fish, 5 mollusks, 28 crustaceans, 1 platyhelminthes and 2 bryozoans. While pathway risk varies by taxon, the highest risk pathways across all taxonomic groups are natural dispersal, hitchhiking/fouling, and intentional release. The taxonomic group predicted to have the most severe impacts on a per species basis is algae, followed by mollusks, and plants. However, the large number of plant and fish species on the surveillance species list means that overall predicted impact (from a taxonomic perspective) is greatest from these two groups. We recommend ways that the surveillance list could be applied to improve aquatic invasive species management efforts: engage in community-based surveillance, inform taxonomic and species surveillance priorities, provide guidance on monitoring protocols for surveillance, quantify the relative risk of various pathways of introduction and identify priority locations for surveillance based on this pathway assessment.