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A small community of bottlenose dolphins Tursiops truncatus residing in Dolphin Bay, Bocas del Toro, Panama is currently the target of the largest cetacean tourism operation in Panama. Boat-based tourism activities are concentrated in Dolphin Bay due to the high site fidelity of dolphins in this area and its potential importance as a calving and nursery ground for females. Many of the individuals routinely exposed to tour boats are females with dependent offspring. Previous tourism impact studies at this site show that tour boats elicit short-term changes in dolphin behavior and acoustic structure, however, the relationship of these responses to the population’s biology and ecology is not clear. Animal behavior is temporally dynamic, therefore, assessing the effects of potential impacts on the time structure of behavior, such as behavioral transitions and time-activity budgets can provide useful information about the biological significance of anthropogenic disturbance. Because the time-activity budget is tied to the energy budget of individuals, information on the former can provide useful information about the energetic costs of tourism to a population. In this study, the behavioral transitions of focal dolphins in Dolphin Bay, Bocas del Toro were analyzed using transition matrix models, a timesequencing analytical technique now widely applied to dolphin behavior to explore the potential impacts of tourism on cetaceans. First-order, time discrete Markov chain models were used to assess the effect of tour boat activities on dolphin behavioral transition probabilities in both control and impact scenarios. The effect of boat interactions was then quantified by comparing transition probabilities of both control and impact chains. Data were also used to construct dolphin activity budgets. Additionally, a Generalized Log Linear Mixed Model (GLMM) was fitted to a subset of the data containing only females with dependent calves to assess the effects of tour boats on this vulnerable age-sex class. The Markov chain analysis revealed that in the presence of tour boats, dolphins were less likely to stay in a socializing state and were more likely to begin travelling, and were less likely to begin foraging while in a traveling state. Additionally, the time-activity budgets showed that foraging decreased as an effect of tour boat presence, and travelling increased, indicating a shift in the important relationship between these two activities. The results of the GLMM showed that females with dependent calves are less likely to forage and more likely to travel when tour boats are present. These behavioral responses are likely to have energetic implications for individuals through two possible mechanisms: reduced energy acquisition and increased energy expenditure. The effect of lost foraging opportunities and increased physical demands may be more pronounced for nursing females whose physiological demands are higher and can potentially lead to poor reproductive outcomes and reduced fitness of individuals. Tour operator compliance with the ARAP No. 2007 Resolution on number and frequency of tour boats interacting with dolphins in Dolphin Bay, as well as approaching distance to females with calves is urgently needed to minimize potential longterm impacts on this small, genetically distinct population.