Carvalho, J.; Poinho, M. I.; Morello, G.; Ramos, F.; Magalhaes, A.

Information about green anacondas (Eunectes murinus) in human care is limited, especially concerning their behavior, welfare, and overall well-being. To help bridge this knowledge gap, this study evaluated how exhibit design enhancements influence E. murinus behavior. The aim was to assess immediate behavioral changes following enclosure modifications and investigate potential habituation over time, ultimately evaluating the effectiveness and longevity of the behavioral changes induced by the improved environment. Systematic observations were divided into three phases: before enclosure improvements, immediately after these modifications, and three weeks later. Enclosure modifications focused on areas less frequented by the anacondas during Phase 1. Results revealed decreased inactivity in Phase 2 and more balanced space use in Phase 3, with anacondas occupying previously underutilized areas, including the vertical dimension of the terrarium. Interaction with exhibit enhancement items increased in the final phase of the study, where a decrease in engagement would be anticipated due to habituation. These results suggested the anacondas required additional time to acclimate to the modifications, even though environmental factors may have contributed to these changes. This study highlights how enclosure enhancements may benefit the welfare of green anacondas while underlining the importance of providing sufficient acclimation time to accurately evaluate the complete behavioral response of the animals.