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Objective: Shark depredation, the full or partial consumption of a hooked fish by a shark before it is landed, is an increasing source of human–wildlife conflict in recreational fisheries. Reports of shark depredation in the catch‐and‐release Tarpon (also known as Atlantic Tarpon) Megalops atlanticus fishery in the Florida Keys are increasing, specifically in Bahia Honda, a recreational fishing hot spot and a putative Tarpon prespawning aggregation site. Methods: Using visual surveys of fishing in Bahia Honda, we quantified depredation rates and drivers of depredation. With acoustic telemetry, we simultaneously tracked 51 Tarpon and 14 Great Hammerheads (also known as Great Hammerhead Sharks) Sphyrna mokarran, the most common shark to depredate Tarpon, to quantify residency and spatial overlap in Bahia Honda. Result: During the visual survey, 394 Tarpon were hooked. The combined observed shark depredation and immediate postrelease predation rate was 15.3% for Tarpon that were fought longer than 5 min. Survival analysis and decision trees showed that depredation risk was highest in the first 5–12 min of the fight and on the outgoing current. During the spawning season, Great Hammerheads shifted their space use in Bahia Honda to overlap with Tarpon core use areas. Great Hammerheads restricted their space use on the outgoing current when compared to the incoming current, which could drive increased shark–angler interactions. Conclusion: Bahia Honda has clear ecological importance for both Tarpon and Great Hammerheads as a prespawning aggregation and feeding ground. The observed depredation mortality and postrelease predation mortality raise conservation concerns for the fishery. Efforts to educate anglers to improve best practices, including reducing fight times and ending a fight prematurely when sharks are present, will be essential to increase Tarpon survival and reduce shark–angler conflict. Impact statementShark depredation in recreational fisheries is an increasing source of human–wildlife conflict in the United States. This study quantified shark depredation in the Tarpon fishery and characterized the spatial ecology of Great Hammerheads and Tarpon in Bahia Honda in the Florida Keys. [ABSTRACT FROM AUTHOR]

The biological consequences of catch-and-release (C&R) angling revolve around interactions between the physiological and behavioural responses of the captured fish and ecological conditions such as the presence of opportunistic predators. Here, we explored the consequences of C&R on adult permit (Trachinotus falcatus), including assessments of depredation rates, their physiological and reflex responses prior to release, post-release behaviour, and post-release predation in diverse habitats in the Florida Keys, USA. We found pre-capture depredation rates were highly variable amongst habitat types, ranging from zero on shallow water flats, to 35.3% and 90.1% on specific reef and shipwreck locations, respectively. Observed predators were all large sharks. Importantly, one of the high predation sites is an important permit spawning location, thus C&R fishing in that locale may be a conservation concern. Physiological stress responses (blood lactate, glucose, pH) and reflex tests indicated that permit were relatively robust to routine angling (fight durations of 1 to 12 min) and handling (air exposure up to 2 min). Short duration post-release tracking using tri-axial acceleration biologgers identified no differences in swimming activity for fish that were kept in water versus those held in the air for 2 min to simulate an admiration period. While this study indicates that permit are relatively robust to C&R angling in terms of stress responses and behavioural impairment, high densities of opportunistic predators at certain fishing locations can result in high rates of pre-capture depredation independent of the state of the animal. Permit angling in locations with high predator densities is a potential conservation issue, especially if specific locations represent important pre-spawning aggregation sites for fish populations that may be more vulnerable to predation and thus depredation. Current C&R best practices (i.e., limiting fight times and air exposure) may not be adequate to ensure permit survival at high predator density sites. Angling-related depredation is often cryptic, yet is a growing conservation concern in many fisheries – we developed and applied a novel framework for identifying cryptic depredation that may be applicable across fisheries. • Permit (Trachinotus falcatus) show resiliency to catch-and-release angling events. • Depredation represents a potential conservation concern at specific sites in the Florida Keys. • Changes in angler behaviour could effective in supporting conservation efforts. [ABSTRACT FROM AUTHOR]