eDNA Probe Development for Amphipods that Qualify as Aquatic Invasive Species (AIS) in the Great Lakes

Abstract:

Class Malacostraca is a diverse group of over 25,000 species and includes the major Crustacean groups of lobsters (Decapoda), woodlice (Isopoda), mysids (Mysida) and side swimmers (Amphipoda). Within any group of organisms, some play valuable roles, and some act as AIS in their environment. AIS are non-native in their environment and their presence potentially causes economic/ecological harm. To better understand the distribution of invasive species in the Great lakes, species presence can be detected with eDNA in filtered water, once discriminating oligonucleotide probes have been developed. In Lake Erie, we have targeted three species of Amphipods for investigation; Echinogammarus ischnus, Gammarus fasicatus, and Gammarus tigrinus. When sampling around Presque Isle, an overwhelming percentage of species were found to be E. ischnus, while the others were rare or non-existent. Due to the prevalence of E. ischnus, they are of most interest in probe development. G. fasciatus is still important because of its classification as a non-native species, that has also been collected locally. No matter the amount collected, developing primers for each species is required because of their close phylogenetic relationships. Natural history research, collection, and probe creation information was collected for these target scuds over 2022 into the winter of 2023. This record and data will aid in the detection of these species throughout the Great Lakes.