Marine fish movement plays a critical role in ecosystem functioning and is increasingly studied with acoustic telemetry. Traditionally, this research has focused on single species and small spatial scales. However, integrated tracking networks, such as the Integrated Tracking of Aquatic Animals in the Gulf of Mexico (iTAG) network, are building the capacity to monitor multiple species over larger spatial scales. We conducted a synthesis of passive acoustic monitoring data for 29 species (889 transmitters), ranging from large top predators to small consumers, monitored along the west coast of Florida, USA, over 3 yr (2016-2018). Space use was highly variable, with some groups using all monitored areas and others using only the area where they were tagged. The most extensive space use was found for Atlantic tarpon Megalops atlanticus and bull sharks Carcharhinus leucas. Individual detection patterns clustered into 4 groups, ranging from occasionally detected long-distance movers to frequently detected juvenile or adult residents. Synchronized, alongshore, long-distance movements were found for Atlantic tarpon, cobia Rachycentron canadum, and several elasmobranch species. These movements were predominantly northbound in spring and southbound in fall. Detections of top predators were highest in summer, except for nearshore Tampa Bay where the most detections occurred in fall, coinciding with large red drum Sciaenops ocellatus spawning aggregations. We discuss the future of collaborative telemetry research, including current limitations and potential solutions to maximize its impact for understanding movement ecology, conducting ecosystem monitoring, and supporting fisheries management.

Mitochondrial control region sequences of 141 alfonsino Beryx decadactylus sampled off the coast of South Carolina were compared with 164 sequences from B. decadactylus collected in the Azores for inferring population structure and demographic history of this deep-water teleost in the North Atlantic Ocean. Analysis of molecular variance showed that 100% of the genetic variation was found within populations, indicating an absence of population structure (Φ(ST) = -0· 003). Neutrality tests and mismatch distribution analyses of pooled sequences suggested that B. decadactylus in the North Atlantic Ocean have undergone population expansion. These results may indicate that transatlantic gene flow occurs, possibly through passive drift of larvae or adult migration. The potential of a shared stock between the eastern and western North Atlantic Ocean will need to be considered if a directed fishery for B. decadactylus were to develop in the U.S.A.

Interspecific interactions can play an essential role in shaping wildlife populations and communities. To date, assessments of interspecific interactions, and more specifically predator-prey dynamics, in aquatic systems over broad spatial and temporal scales (i.e., hundreds of kilometers and multiple years) are rare due to constraints on our abilities to measure effectively at those scales. We applied new methods to identify space-use overlap and potential predation risk to Atlantic tarpon (Megalops atlanticus) and permit (Trachinotus falcatus) from two known predators, great hammerhead (Sphyrna mokarran) and bull (Carcharhinus leucas) sharks, over a 3-year period using acoustic telemetry in the coastal region of the Florida Keys (USA). By examining spatiotemporal overlap, as well as the timing and order of arrival at specific locations compared to random chance, we show that potential predation risk from great hammerhead and bull sharks to Atlantic tarpon and permit are heterogeneous across the Florida Keys. Additionally, we find that predator Lucas P. Griffin and Grace A. Casselberry share co-first authorship and contributed equally to this work.

Data from the Integrated Tracking of Aquatic Animals in the Gulf of Mexico (iTAG) network, and sister networks, were used to evaluate fish movements in the Florida Keys-an extensive reef fish ecosystem just north of Cuba connecting the Atlantic Ocean and Gulf of Mexico. We analysed ~2 million detections for 23 species, ranging from reef fish such as Nassau grouper (Epinephelus striatus, Serranidae) to migratory apex predators such as white sharks (Carcharodon carcharias, Lamnidae). To facilitate comparisons across species, we used an eco-evolutionary movement strategy framework that identified measurable movement traits and their proximate and ultimate drivers. Detectability was species-specific and quantified with a detection potential index. Life stages detected in the study area varied by species and residency varied with life stage. Four annual movement types were identified as follows: high site-fidelity residents, range residents, seasonal migrants and general migrants. The endangered smalltooth sawfish (Pristis pectinata, Pristidae), a seasonal migrant, exhibited the greatest within-ecosystem connectivity. Site attachment, stopover and deep-water migration behaviours differed between individuals, species and annual movement types. All apex predators were migratory. General migrants were significantly larger than fish in the other movement types, a life-history and movement trait combination that is common but not exclusive, as many small pelagics also migrate.Most teleosts exhibited movements associated with spawning. As concerns grow over habitat and biodiversity loss, multispecies movescapes, such as presented here, are expected to play an increasingly important role in informing ecosystem-based and non-extractive fisheries management strategies.

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