Ballast water transport has overwhelmingly contributed to the introduction of aquatic invasive species (AIS) in the Laurentian Great Lakes and waters around the globe. AIS in ballast water can be detrimental to receiving native ecosystems and difficult to detect and control. Understanding risk-release relationships and the early detection of AIS is imperative to protecting native communities. Early detection methods are lacking and an understanding of establishment risk across multiple species is needed. Using mesocosms, propagule pressure and establishment is investigated to understand risk-release relationships of several protist species. Protist densities of 0 - 100 cells/mL were inoculated into mesocosms filled with Duluth-Superior Harbor water and sampled weekly for 4 weeks. Experiments evaluated three surrogate “invaders”: Haematococcus pluvialis, Trachelomonas abrupta, and Chrysosphaerella sp. Logistic models predicted the minimum surrogate protist densities resulting in successful establishment, thereby providing information on ballast water risk-release relationships. Ongoing work will couple DNA with morphological counts to develop a potential tool for molecular detection of non-native species in ballast or environmental samples. This research will provide insight to the validity of mesocosm-based experiments to study risk-release relationships across protist species, the coupling of morphological and DNA data to model population establishment and trajectory, and species-specific molecular detection thresholds for protists.

Primary Presenter: Abigail Latanich, Natural Resources Research Institute (armst255@d.umn.edu)

Authors:

Meagan Aliff, University of Minnesota, Duluth - Natural Resources Research Institute  (aliff002@d.umn.edu)

Courtney Larson, University of Minnesota, Duluth and the United States Environmental Protection Agency  (lars4263@d.umn.edu)

Euan Reavie, University of Minnesota, Duluth - Natural Resources Research Institute  (ereavie@d.umn.edu)