We present a novel method utilizing in-situ video data of fish locomotion to calculate thrust. This methodology was applied to several large elasmobranch species, which are typically challenging to measure. Using motion tracking software, we analyzed video footage of both wild and captive sharks to track their position and speed. In order to estimate the total force output, we used the tail/body motion in respect to the surrounding medium assuming equilibrium conditions. The force output for each shark was converted into scaled thrust, enabling comparisons independent of size. This scaled thrust was then analyzed across swimming modes and caudal fin morphology, serving as a proxy for each species’ behavioral ecology. Through PCA analysis we demonstrate the coupling between morphological traits and hydrodynamic forces. The ratio of the upper to lower lobe of the caudal fin (CLAR) emerged as a strong predictor of scaled thrust, accounting for over 80% of observed variation. These morphological traits, a proxy for behavioral ecology, appear to be the most suitable predictor of hydrodynamic forces given the quantitative nature of the variable compared to the categorical classifications of swimming mode. Our findings indicate that coastal pelagic species exhibited similar but significantly lower scaled thrust values than benthic species, suggesting that benthic species may be less efficient, expending more energy to remain aloft or compensate for drag relative to generating forward motion. Our findings demonstrate how morphological traits have evolved to optimize energy expenditure based on behavioral ecology, highlighting a tradeoff between benthic and coastal pelagic species. We propose that the unique ecological niches of these species drive behavioral changes that result in morphological adaptations to optimize performance. Given the relatedness between morphology/behavioral ecology and swim mode, selected pressure overtime could also explain the ecological need of different swim modes.