State: Illinois

County: Vermilion

Water Bodies Affected: Salt Fork and Middle Fork Vermilion Rivers

Translocation of freshwater mussels has been a restoration tool for decades; however, the efficacies have yet to be evaluated. This project will implement a robust monitoring plan with recently translocated populations of Northern Riffleshell and Clubshell in the Vermilion River, Wabash basin, in Illinois. Results of this project will help develop successful and cost effective strategies for future reintroductions by identifying factors that influence survival and optimize monitoring.

The Vermilion River basin (Wabash), Illinois has a working wildlife action plan, “The Vermilion River (Middle Fork, North Fork, & Salt Fork) & Little Vermilion River Conservation Opportunity Area Wildlife Action Plan”. A specific goal of this action plan is to improve wildlife habitat quality by increasing populations of Species in Greatest Need of Conservation (Goal 2, Objective 3), i.e. federally listed Northern Riffleshell and Clubshell. A specific objective of the USFWS Northern Riffleshell and Clubshell Recovery Plan is to re-establish viable populations in 10 separate river drainages via augmentation and reintroduction. To date, eight sites in the Vermilion River basin have received translocations of Northern Riffleshell and Clubshell. Gaining a specific measure of success (i.e., survival) of this translocation and providing guidance for future reintroductions is a necessary step towards defining success of the Vermillion River basin wildlife action plan and USFWS recovery plan.

Within 24 months we will implement a Robust Design monitoring program on translocated populations of the federally listed Northern Riffleshell and Clubshell. We will provide estimates of survival for each site (8 total), specific detection rates, and identify biological and ecological factors that make mussels amenable to translocation (size, age, time of translocation). We will monitor PIT tagged Northern Riffleshell and Clubshell in the Vermillion River (Wabash) Illinois, using a handheld tag reader. Primary sampling periods will occur every 3 months and repeat samples each primary period. Capture histories will be analyzed using Program MARK. The outcome of this project will provide specific guidelines for best translocation time, size or age of mussel, and the best times to monitor populations to optimize monitoring.