Association for Behavior Analysis International

This symposium involves three presentations. All three presentations involve different aspects of the operant conditioning of lake sturgeons (Acipenser fulvescens) – a species whose operant behavior has not been studied. It is important to study the operant conditioning of this species for several reasons. Most importantly, this species evolved around 200 – 250 million years ago and has changed morphologically so little in the time it has existed that it has been it has been called a “living fossil”. Thus, studying the operant conditioning of this species could contribute to our knowledge of the evolution of operant conditioning. Also important is the fact that this species is considered threatened so that studying its operant conditioning could help develop procedures that promote its survival. The first presentation in this symposium demonstrates that food can be used as reinforcement to operantly condition lake sturgeons to swim to a particular location in an aquarium. The second presentation demonstrates that darkness can be used as a reinforcer to condition lake sturgeons to swim to a particular location in an aquarium, and also to maintain the learned behavior on fixed-ratio schedules. The third presentation examines the effects of varying amount of light reduction as reinforcement for this species.

In an experimental tank (ET), two experimentally naïve lake sturgeons (Acipenser fulvescens) were operantly conditioned to enter one of four target areas where they received an auditory response-feedback stimulus (RFS) in the form of a click sound and – according to the prevailing FR schedule – 10 seconds of darkness. A multiple-baseline-across-subject’s design was used. Visual observation and a video-tracking system (VTS) monitored the number of responses emitted on each of the four target areas. The target areas were in the corners of the ET and had to be entered by the subject to constitute a response. The experiment involved the following phases: (1) no-feedback baseline (NFB); (2) discriminative stimulus baseline (DSB); (3) response-feedback baseline (RFSB); and (4) fixed-ratio (FR n). The data indicated a preference for the target area that produced darkness, which implies that darkness is a reinforcer for this species. This preference was indicated by a greater number of target area responses for the target area whose entry into produced darkness, and greater activity in and around that area relative to baseline phases. Furthermore, when the n of the FR n was increased the rate of responding also increased.