Since zoo visitors are a routine component of zoological environments, it is important to understand how visitor presence influences the behavior and welfare of zoo-housed animals. A noted outcome of these interactions is the visitor effect, which is the influence that crowds play on the behavior and activity of zoo-housed animals. ZooTampa at Lowry Park houses six Bornean orangutans, popular amongst guests, and here we aimed to understand how noise levels and crowd size influence their behavior and habitat space use. To examine this, from June to October 2025, we recorded state and all occurrence behavior during 30-minute continuous focal observations, and decibel level, habitat location, and crowd size at three-minute intervals throughout the observation session. Using generalized and cumulative mixed models with individual ID as a random effect, we found that social affiliative behavior decreased as noise levels increased (p=0.033) and found an increase in head cover events with a higher decibel level (p=0.014).  We also found that with a large crowd size, there was a smaller probability for orangutans to be lower in the habitat (p <0.0001). These orangutans have been zoo-housed for their entire lives, where interactions with visitors are regulated in the interest of animal welfare. Given that we only observed minor behavioral changes, our results suggest the ZooTampa orangutans have distinct ways in which they can use their environment to mitigate visitor presence, such as maximizing their vertical habitat. 

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