Sponsor: Introduced Fish Section
Seventeen speakers reported on improvements in understanding of the effects of hydrology on nonnative aquatic species. The majority of speakers focused on Asian carp in the Mississippi River drainage, providing information on the effects of flow on spawning, recruitment, range expansion, and movement patterns. Several speakers used the U.S. Army Corps of Engineers Hydrologic Engineering Center’s River Analysis System (HEC-RAS) to model hydraulic conditions and the U.S. Geological Survey’s Fluvial Egg Drift Simulator (FluEgg) to link hydraulics to transport and dispersal of Asian carp eggs. Along with these models, telemetry data has aided the understanding of spawning events and movements of Asian carp around various dams and throughout Mississippi River tributaries (Iowa, Illinois, and Missouri Rivers). Also discussed were habits of the nonnative Rusty Crayfish, a species whose size relates to its success in different volumes of flow. A presentation on the Asian Swamp Eel in Georgia demonstrated a higher species detection probability at higher temperatures. Afternoon speakers discussed desert fishes, where speakers discussed the importance of flow variability to maintain native populations and flush out nonnatives. Overall, the discussion focused on an array of altered hydrologic regimes and the relationships between altered flows and the success of nonnative species. Read the abstracts here.
—Larissa Lee and Zach Nemec, Graduate Research Assistants, University of Arizona