Trophic ecology of hairy conger eel Bassanago albescens in the Southwest Atlantic and its implications for the ecosystem-based fishery management


  • Gabriela Blasina Instituto Argentino de Oceanografía (IADO), Universidad Nacional del Sur (UNS)-CONICET, Camino La Carrindanga km 7.5, B8000FWB - Bahía Blanca, Argentina - Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur (UNS), San Juan 670, B8000ICN - Bahía Blanca, Argentina
  • Luciano Izzo Laboratorio de Biología de Peces, Departamento de Ciencias Marinas, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata (UNMdP), Funes 3350, B7602AYL - Mar del Plata, Argentina
  • Agustín De Wysiecki Centro para el Estudio de Sistemas Marinos (CESIMAR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Boulevard Brown 2915, U9120ACD - Puerto Madryn, Argentina
  • Daniel Figueroa Laboratorio de Biología de Peces, Departamento de Ciencias Marinas, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata (UNMdP), Funes 3350, B7602AYL - Mar del Plata, Argentina



Anguilliformes, ecosystem-based fishery management, feeding habits, ontogenetic changes


This study aimed to determine the diet composition and feeding strategies of the hairy conger eel Bassanago albescens in the Southwest Atlantic (35° S-45° S), from stomach contents analysis of 222 specimens. The diet consisted mainly of cephalopods, followed by isopods, amphipods, ophiuroids, brachyurous and polychaetes. Results showed significant differences in the composition of the diet between sexes, regions and size classes that were reflected in the changes in the foraging strategy. The consumption of squid Illex argentinus progressively increased with a growing predator size, where the largest individuals showed specialization in the consumption of this particular prey. We propose these dietary changes would be related to morphological limitations and abilities associated with the body size of B. albescens, with larger individuals having access to larger prey. Our results help to understand the biology of a species that has a sympatric distribution with two key species in the Argentine fisheries: hake Merluccius hubbsi and I. argentinus, with evidence of a strong trophic interaction between them. This new information on the resources involved would allow an optimization of the fisheries management under an ecosystem-based criterion.


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How to Cite

Blasina G, Izzo L, De Wysiecki A, Figueroa D. Trophic ecology of hairy conger eel Bassanago albescens in the Southwest Atlantic and its implications for the ecosystem-based fishery management. Mar Fish Sci [Internet]. 2021Jul.1 [cited 2021Sep.17];34(2):181-95. Available from: