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

DE WYSIECKI, AGUSTÍN M.; BARNETT, ADAM; CORTES FEDERICO; WIFF RODRIGO; MERLO PABLO; JAUREGUIZAR, ANDRÉS J.; AWRUCH, CYNTHIA A.; TROBBIANI, GASTÓN A.; ALEJO J. IRIGOYEN

Royal Society Open Science

Royal Society Publishing

Año: 2023 vol. 10

Essential habitats support specific functions for species, such asreproduction, feeding or refuge. For highly mobile aquaticspecies, identifying essential habitats within the widerdistribution range is central to understanding species ecology,and underpinning effective management plans. This studyexamined the movement and space use patterns of sevengillsharks (Notorynchus cepedianus) in Caleta Valdés (CV), aunique coastal habitat in northern Patagonia, Argentina.Seasonal residency patterns of sharks were evident, withhigher detectability in late spring and early summer andlower during autumn and winter. The overlap between theresidency patterns of sharks and their prey, elephant seals,suggests that CV functions as a seasonal feeding aggregation site forN. cepedianus. The study also found sexual differences in movement behaviour, with malesperforming abrupt departures from CV and showing increased roaming with the presence of moresharks, and maximum detection probability at high tide. These movements could be related todifferent feeding strategies between sexes or mate-searching behaviour, suggesting that CV mayalso be essential for reproduction. Overall, this study highlights the importance of coastal sites asessential habitats forN. cepedianusand deepens our understanding of the ecological role of thisapex predator in marine ecosystems.