Appetitive conditioning technique reveals behavioural limits to passage performance in fishes

Abstract

SynopsisNumerous environmental features have the potential to act as 'barriers' to fishes in the field. Passage of these 'barriers' depends on two main properties: willingness (behavioural) and physiological capacity. The physiological swimming capacity of fishes has been well studied. However, because most barrier research has focused on the population level effects of man -made barriers, little attention has been given to the behavioural aspects of fish passage. We used appetitive conditioning to create a simple laboratory based protocol to estimate behavioural limits to fish passage. We tested our protocol using barrier height (or passage space) as a model. Our protocol successfully identified behavioural limits in two species, juvenile rainbow trout, Oncorhynchus mykiss, and fathead minnows, Pimephales promelas. Our most interesting observation was that even a partial, submerged barrier had the potential to block fish movements. Our results suggest a potential use for conditioning techniques in assessing factors that constitute behaviour barriers to fishes. This information may help us to better predict fish movements in the field and may help us to design barriers that are more efficient at passing fishes.

Effect of river fragmentation and flow regulation on occurrence of landlocked brown trout in a fish ladder

“…An alternative explanation of repeated occurrence of fish in the ladder can be an effort by the fish to pass a barrier based on repeated occasions, which is verified by repeated entrances of an individual into the ladder. Binder and Don Stevens (2004) described the individual efforts of the rainbow trout Oncorhynchus mykiss (W.) to hurdle an experimental barrier. Lucas and Batley (1996) observed that the barbel Barbus barbus (L.) repeatedly recognized the situation for successful passage over a weir.…”

“…Fish occurrence in ladders appears to be an individual fish choice, resulting in its repetitive entrance into a ladder. Models of fish occurrence in ladders based on observations at the individual level are lacking; however, models have been used to predict migratory behaviour for entire populations (Binder and Don Stevens, 2004).…”

The Effects of Road Culverts on Nekton in New England Salt Marshes: Implications for Tidal Restoration

“…The potential also exists for fish to swim through culverts with high‐speed currents in the direction of water flow. Despite the tendency of fish to move in the direction of tidal flow (Deegan & Garritt 1997; Halpin 1997), culverts that greatly accelerate water velocity may serve as behavioral barriers to fish movement (Binder & Stevens 2004). On the basis of the decreased passage rates measured at culverts that increase water velocity, our data support the idea that undersized culverts with accelerated currents restrict movements of F. heteroclitus populations between upstream and downstream areas.…”