Browsing by Author "De Wysiecki, Agustin M."

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    First report of the hapuku wreckfish Polyprion oxygeneios (Polyprionidae) in Argentinian waters
    (2021) Milessi, Andres C.; De Wysiecki, Agustin M.; Carvalho Filho, Alfredo; Wiff, Rodrigo
    The hapuku wreckfish Polyprion oxygeneios is recorded for the first time in Argentinian waters. Four specimens were caught off Mar del Plata (38 degrees S, Argentina) in depths between 60 and 260 m during austral summer (three by sport fishers and one in a research cruise). Up to the present, this species was consistently misidentified with its congener, the common wreckfish P. americanus, off Argentina. These records represent a connection between previous records from Brazil and the more austral circumglobal distribution of the species.
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    The essential habitat role of a unique coastal inlet for a widely distributed apex predator
    (2023) De Wysiecki, Agustin M.; Barnett, Adam; Cortes, Federico; Wiff, Rodrigo; Merlo, Pablo J.; Jaureguizar, Andres J.; Awruch, Cynthia A.; Trobbiani, Gaston A.; Irigoyen, Alejo J.
    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 Valdes (CV), 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 CV functions as a seasonal feeding aggregation site for N. cepedianus. The study also found sexual differences in movement behaviour, with males performing abrupt departures from CV and showing increased roaming with the presence of more sharks, and maximum detection probability at high tide. These movements could be related to different feeding strategies between sexes or mate-searching behaviour, suggesting that CV may also be essential for reproduction. Overall, this study highlights the importance of coastal sites as essential habitats for N. cepedianus and deepens our understanding of the ecological role of this apex predator in marine ecosystems.