Do Boat Traffic and Habitat Features Shape Habitat Use by Guiana Dolphins ( Sotalia guianensis ) in a Brazilian Estuary?

ABSTRACT Increasing boat traffic in estuarine environments poses growing challenges for the conservation of coastal cetaceans, yet how these pressures interact with habitat features to shape spatial use remains poorly understood. This study investigated the influence of boat traffic and habitat features on the spatial use and habitat selection of Guiana dolphins ( Sotalia guianensis ) in Pontal Bay, a northeastern Brazilian estuary, using shore‐based observations and theodolite tracking of dolphin and boat trajectories collected between April 2015 and January 2016. Utilization distribution and habitat selection analyses revealed substantial overlap between dolphins and boats, particularly in deeper areas. At finer scales, however, dolphins preferentially used areas with lower boat traffic, greater depths, and proximity to fishing centers, while avoiding shallow zones and river edges. These patterns indicate a scale‐dependent trade‐off between access to foraging opportunities and exposure to anthropogenic disturbance. Our findings highlight the importance of integrating environmental and human‐related factors into estuarine management and support the need for measures that regulate vessel activity within key dolphin habitats.