Swimming responses of larval and juvenile freshwater fishes to nearshore and offshore water sources

Abstract

AbstractDispersal of young fish through wind‐driven currents has a growing research focus in large freshwater lakes; however, the influence of behaviour on such dispersal has not been tested. Fish may orient to different environmental cues and use swimming behaviours to navigate towards or retain their position within important habitats. To examine the ability of larval and juvenile fishes of the Laurentian Great Lakes to perceive and orient to nearshore or offshore habitats, we carried out a series of behavioural trials in a flume in which fish choose between different combinations of nearshore and offshore water, and well water. Water and a natural assemblage of larval and juvenile nearshore fish (Dominant species: white sucker, Catostomus commersonii, and spottail shiners, Notropis hudonius) used in the experiment were collected from northern Lake Michigan near Beaver Island. Results of our study suggest that young fish are capable of distinguishing and responding to different water sources, indicating a potential to orient within their environment, such as through the use of olfactory cues. We did not see a difference in fish response to changing concentrations of water cues, possibly suggesting that the threshold for fish response occurs at lower concentrations than were tested in our experiments. This preliminary study into orientation of Great Lakes fishes demonstrates the capacity of these fish to orient to cues in water sources and indicates the need to consider active movement in future studies of larval dispersal and habitat choice in the large freshwater lakes.