Hurricanes are natural disturbances that can have tremendous impacts on coastal zones including long-term changes in conditions that may affect ecosystem structure, community dynamics, and trophic interactions. Previous studies have demonstrated that juvenile sharks may leave nurseries as hurricanes approach. For example, juvenile bull sharks (Carcharhinus leucas) abandoned their nursery in the coastal Everglades when hurricane Irma approached Florida in 2017 and traveled northeast along the coast. How hurricanes might affect the foraging behavior of these estuarine top predators remains poorly understood. In this study, stable isotope analyses were conducted on muscle and plasma samples from sharks caught a year before and few months after Hurricane Irma to investigate potential differences in ẟ15N and ẟ13C isotopic values. Such shifts provide insights into potential changes in relative trophic level and basal food web sources supporting their diets, respectively. There were no significant changes found in ẟ13C, but, ẟ15N values were lower in individuals sampled after the hurricane. These findings suggest that juvenile bull sharks, or their prey, were likely feeding at lower trophic levels after the hurricane and/or shifted to consuming prey with low protein content.
