Numeric Simulation Demonstrates That the Upstream Movement of Invasive Bigheaded Carp Can Be Blocked at Sets of Mississippi River Locks-and-Dams Using a Combination of Optimized Spillway Gate Operations, Lock Deterrents, and Carp Removal

Invasive bigheaded carp are advancing up the Upper Mississippi River by passing through its locks-and-dams (LDs). Although these structures already impede fish passage, this role could be greatly enhanced modifying how their spillway gates operate, adding deterrent systems to locks, and removing carp. This study examined possibility using numeric modeling empirical data, which evaluated all three options on an annual basis in both single LDs pairs under different river flow conditions. Over 100 scenarios were modeled. While approaches showed promise, ranging from 8% 73% reductions many pass a LD, when employed together at of LDs, upstream movement rates invasive reduced 98–99% current levels. gate operation is least expensive option, efficacy drops high flows, so lock deterrents and/or removal fishing/trapping required move towards complete blockage. Improved also offset need for more efficient removal. model help prioritize research management actions containing