Thomson, A. S., & O’Brien, S. L. (2025). Examining the visitor effect in zoo-housed semi-aquatic turtles. Animal Behavior and Cognition, 12(1), 122-137.  https://doi.org/10.26451/abc.12.01.06.2025

Zoo visitors constitute a major part of a zoo animal’s environment and can have measurable impacts on their behavior and welfare, a phenomenon referred to as the visitor effect. The influence of visitors on animal welfare is generally categorized as positive, neutral, or negative, with most, but not all, studies reporting a negative or neutral relationship. However, most studies on visitor effects have been conducted with mammals, and therefore more research is needed to understand how zoo animals of other taxonomic groups, such as reptiles, are impacted by zoo visitors. At Lincoln Park Zoo (Chicago, IL, USA), a semi-aquatic turtle enclosure is located indoors next to a large children’s play structure. This indoor environment can become busy and loud during peak hours, which could impact the turtles’ welfare. To assess whether the turtles are collectively impacted by visitors, we recorded the turtles’ space use within their enclosure with changing visitor presence and visitor activity. We found no evidence that the turtles’ visibility or their propensity to seek coverage was affected by visitor presence or visitor activity. However, our data indicates that the turtles tended to be further from the visitor viewing glass as the number of people on the play structure increased and as visitor noise level increased. The other environmental variables measured -- crowd size in front of the turtle enclosure and tapping on the visitor viewing glass – did not significantly impact turtle space use.

Animal welfare, Aquarium, Reptile, Turtle, Visitor effect, Zoo