Successful lake sturgeon use of a prototype upstream fishway on the Menominee River in northern Wisconsin

Historically, lake sturgeon (Acipenser fulvescens) were abundant in Lake Michigan with free and unobstructed access to the feeding and spawning areas within its many tributaries.  Construction and operation of hydroelectric dams has destroyed this connection to spawning grounds.  One method for reestablishing this lost connection is to create an artificial pathway such as a fish passage facility (i.e., fish ladder).  To help answer some basic questions, such as will sturgeon use a fishway, we constructed a prototype fish passage structure below a hydroelectric dam on the Menominee River in northern Wisconsin.  This structure was equipped with a PIT tag reader antenna and two underwater video cameras equipped with infrared lights.  All monitoring equipment were installed and activated before the start of the spring spawning season.  PIT tag records indicated that 86 tagged lake sturgeon used the passage structure, with many going through the structure multiple times.  Video data verified these results and also indicated that these sturgeon moved through the structure rather quickly (mean = 3 sec) and at a rate of about one sturgeon every two hours during the spawning season.  Extrapolated to the whole sturgeon population, nearly 20% of the spawning population went through this prototype fishway.