The essential habitat role of a unique coastal inlet for a widely distributed apex predator

Essential habitats support specific functions for species, such as reproduction, feeding or refuge. For highly-mobile aquatic species, identifying essential habitats within the wider distribution range is central to understanding species ecology, and underpinning effective management plans. This study examined the movement and space use patterns of sevengill sharks (Notorynchus cepedianus) in Caleta Valdés, a unique coastal habitat in northern Patagonia, Argentina. Seasonal residency patterns of sharks were evident, with higher detectability in late spring and early summer and lower during autumn and winter. The overlap between the residency patterns of sharks and their prey, elephant seals, suggests that Caleta Valdés functions as a seasonal feeding aggregation site for N. cepedianus. The study also found sexual differences in movement behavior, with males performing abrupt departures from Caleta Valdés and showing increased roaming with the presence of more sharks, and maximum detecti...