Response of spawning lake sturgeon to change in hydroelectric facility operation
spawning, lake sturgeon, sturgeon, hydroelectric, adult, relicensing, activity, survival
Journal or Book Title
Transactions of the American Fisheries Society
Spawning of lake sturgeon (Acipenser fulvescens) was documented from 1987 to 1992below the Prickett hydroelectric facility on the Sturgeon River, a tributary to Portage Lake,Michigan. Lake sturgeons were captured at the spawning site with dip nets during periods ofreduced flow. A change in the spawning characteristics of the population was noted thatcorresponded to a change in the operation of the hydroelectric facility. In 1987 and 1988 thefacility operated in a peaking mode, which resulted in large daily fluctuations in river flows. Theyears 1989 and 1990 were years of transition, and in 1991 and 1992 the facility released nearrun-of-the-river (ROR) flows. Under near-ROR flows, which were more natural, adult lakesturgeons spent 4&8211;6 weeks less at the spawning sites, 74% more fish were observed,weights were greater due to a 68% increase in number of females, and fish had increasedreproductive readiness. The change in flow regime was the result of a Federal Energy RegulatoryCommission relicensing action. The positive response observed in lake sturgeon spawningactivity that resulted from the change of facility operation to near-ROR flows should be beneficialto the survival and perpetuation of this population. Similar results may be experienced in otherlake sturgeon waters affected by manipulated flow regimes.