Modifying Dam Operation to Inhibit the Spread of Bigheaded Carps in the Upper Mississippi River

Fish swimming performance data suggests that flows through the lock and dam structures in the Upper Mississippi River likely serve as a primary check to upstream movement of invasive bigheaded carps (Hypophthalmichthys spp.) and other fishes.  Our project seeks to identify changes to gate operation that might further inhibit passage of bigheaded carp while having minimal impacts on desirable native fish.  To accomplish this, we have developed a swimming-fatigue and optimal path selection model that extends upon conventional swimming-fatigue time models to accommodate three-dimensional movements and turbulent fluctuations to predict the likelihood of upstream fish passage.  We are working closely with the U.S. Army Corps of Engineers at a local and national scale to obtain critical information on adult carp swimming, hydrologic data, and identify a plan to implement the proposed changes to gate operation.  This work is part of an overarching management plan that will optimize the lock and dam systems for blocking bigheaded carp through gate modifications while using acoustical deterrents in locks. In this talk we will discuss our collaborations, model development, initial findings, and how they could be used to manipulate gate operation for management purposes. (Funded by Minnesota Environmental and Natural Resources Trust Fund).