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Reported here are the relationships among morphological (i.e., body condition) and biochemical (i.e., plasma concentrations of triglycerides, cholesterol, free fatty acids, and ketone bodies and ketone body ratios) parameters related to energy storage and use, as well as the variation of such parameters, for 107 free‐ranging nurse sharks Ginglymostoma cirratum sampled off South Florida. Immature G. cirratum exhibited a higher variance in body condition, plasma free fatty acid concentrations and ketone body ratios compared to adults. Mature female G. cirratum had significantly higher body condition than mature males, driven by a seasonal increase in mature female body condition during the wet season. Mature male G. cirratum showed a decrease in the ketone body β‐hydroxybutyric acid during the dry season. Taken together, this study provides a baseline assessment of body condition and internal physiological state for a data‐poor marine species and demonstrates significant ontogenetic, sexual and seasonal variation in G. cirratum energetic state. As concluded by other studies of energy metabolism in free‐ranging sharks, this research highlights the importance of considering intraspecific patterns and sampling context for inferring the drivers of variation. [ABSTRACT FROM AUTHOR]

Aquatic ecosystems face numerous anthropogenic threats associated with coastal urbanization, with boat activity being among the most prevalent. The present study aimed to evaluate a potential relationship between boat activity and shark space use in Biscayne Bay, Florida (USA), a coastal waterway exposed to high levels of boating. Spatiotemporal patterns in boat density and traffic were determined from aerial surveys and underwater acoustic recorders, respectively. These data were then compared with residency patterns of bull (Carcharhinus leucas), nurse (Ginglymostoma cirratum) and great hammerhead (Sphyrna mokarran) sharks quantified through passive acoustic telemetry. Results were mixed, with no detectable relationship between boat density and shark residency for any of the species. Hourly presence of G. cirratum decreased with increasing boat traffic, a relationship not seen in the other two species. Explanations for these results include habituation of sharks to the high levels of chronic boat activity in the study area and interspecific differences in hearing sensitivity. • Spatiotemporal patterns of boat activity compared to space use of 3 shark species. • Boat activity measured via aerial surveys and passive acoustic monitoring. • No relationship detected between boat densities and daily shark residencies. • Hourly nurse shark presence was negatively related to boat traffic. • Findings provide insights into effects of urbanization on marine predators. [ABSTRACT FROM AUTHOR]