Ontogenetic changes in the feeding strategy of Lepidonotothen nudifrons (Pisces, Nototheniidae) off the South Shetland islands and the Antarctic Peninsula

• Published in: Polar Research
• Main Authors: Blasina, Gabriela Elizabeth, Lopez Cazorla, Andrea Cecilia, Deli Antoni, Mariana Yanel, Bruno, Daniel Osvaldo, Delpiani, Sergio Matias, Díaz de Astarloa, Juan Martín
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley Blackwell Publishing, Inc
• Subjects: ANTARCTIC FISH DIET; DOMINANT PREY; FEEDING STRATEGY; FOOD WEB; TROPHIC LEVEL; ZONERELATED CHANGES; https://purl.org/becyt/ford/1.6; https://purl.org/becyt/ford/1; Antarctic; The Antarctic; Antarctic Peninsula; South Shetland Islands; Argentino; Argentina; Lopez; Antarc*; Polar Research; Copepods
• Online Access: http://hdl.handle.net/11336/64514

The diet and feeding strategy of Lepidonotothen nudifrons off the South Shetland Islands and the Antarctic Peninsula, as well as their variation in relation to ontogenetic stage (juvenile– adult) and sampling area, were determined by stomach contents analysis. Additionally, the trophic level of this species was estimated to determine its position within the Antarctic food web. Out of 247 specimens with prey in their stomachs, 144 were caught near the South Shetland Islands and 103 off the Antarctic Peninsula. Ontogenetic changes in the trophic ecology of L. nudifrons were observed in both areas and were mainly related to a decrease of copepods and an increase of euphausiids in the diet. The diet of juveniles from the South Shetland Islands was characterized by the dominance of calanoid copepods, followed by isopods and amphipods, whereas diet off the Antarctic Peninsula was dominated by amphipods and cyclopoid copepods. The diet in adults was dominated by amphipods and euphausiids in both areas. The specialization of individual predators on different prey types was observed when considering the whole population of L. nudifrons, but when ontogenetic stages were considered separately it showed a more mixed feeding strategy, with different dominant prey for each class. Although the trophic level increased with fish size, L. nudifrons can be classified as secondary consumer throughout its lifespan. Fil: Blasina, Gabriela Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentina Fil: Lopez Cazorla, Andrea Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. ...