The Swimming and Jumping Ability of Three Small Great Plains Fishes: Implications for Fishway Design

There is a distinct need for fishway designs that are passable by small-bodied fishes. Like many lotic systems worldwide, the streams of the North American Great Plains are frequently fragmented by instream structures and other potential migration barriers. This makes small-bodied fishes of the North American Great Plains appropriate species to use for fishway development. The swimming and jumping abilities of brassy minnow Hybognathus hankinsoni, Arkansas darters Etheostoma cragini, and common shiners Luxilus cornutus, acclimated to water temperatures of 10, 17.5, and 25 degrees C, were quantified in the laboratory. Endurance increased with temperature for brassy minnow but not for the other two species. Based on swimming trial results, current velocities in fishways should not exceed 64 cm/s for brassy minnow or common shiners and 32 cm/s for Arkansas darters. Jumping experiments showed that the presence of a low vertical barrier (5 cm high) dramatically reduced the probability of upstream movement of all three species. Brassy minnow jumped a maximum of 15 cm at 25 degrees C, and common shiners jumped a maximum of 10 cm at 17.5 degrees C. Neither species jumped at 10 degrees C. Arkansas darters did not jump at any temperature. Behavioral observations also indicated that a submerged weir may inhibit the upstream movement of Arkansas darters. Based on the results of this laboratory study, water velocities of less than 0.75 m/s and avoidance of fishways with vertical drops or weir-type structures will increase the probability of successful passage of small-bodied fishes.