Food habits of the broad nose skate, Bathyraja brachyurops (Chondrichthyes, Rajidae), in the South-west Atlantic

BELLEGGIA, M; MABRAGAÑA, E; FIGUEROA, D. E; SCENNA, L. B; BARBINI, S. A; J. M. DÍAZ DE ASTARLOA

SCIENTIA MARINA

Lugar: Barcelona; Año: 2008 vol. 72 p. 701 - 710

0214-8358

Food habits of Bathyraja brachyurops were studied based on stomach content analyses of 346 specimens collected from research cruises carried out from 2003 to 2005 on the Argentinean continental shelf (36oS-55oS). A total of 265 stomachs (76.6%) contained food, and thirty-five taxonomic levels of prey were identified. The most important prey were fishes followed by isopods. Trophic level analysis revealed that B. brachyurops is a tertiary consumer throughout its life history. There were no differences between sexes and regions in the diet composition, but dietary shifts with ontogeny were found. The Levins’ standardized index indicated wider niche breadth for small skates, whereas larger skate specimens showed a narrow niche breadth with a specialization in fishes.Bathyraja brachyurops were studied based on stomach content analyses of 346 specimens collected from research cruises carried out from 2003 to 2005 on the Argentinean continental shelf (36oS-55oS). A total of 265 stomachs (76.6%) contained food, and thirty-five taxonomic levels of prey were identified. The most important prey were fishes followed by isopods. Trophic level analysis revealed that B. brachyurops is a tertiary consumer throughout its life history. There were no differences between sexes and regions in the diet composition, but dietary shifts with ontogeny were found. The Levins’ standardized index indicated wider niche breadth for small skates, whereas larger skate specimens showed a narrow niche breadth with a specialization in fishes.oS-55oS). A total of 265 stomachs (76.6%) contained food, and thirty-five taxonomic levels of prey were identified. The most important prey were fishes followed by isopods. Trophic level analysis revealed that B. brachyurops is a tertiary consumer throughout its life history. There were no differences between sexes and regions in the diet composition, but dietary shifts with ontogeny were found. The Levins’ standardized index indicated wider niche breadth for small skates, whereas larger skate specimens showed a narrow niche breadth with a specialization in fishes.B. brachyurops is a tertiary consumer throughout its life history. There were no differences between sexes and regions in the diet composition, but dietary shifts with ontogeny were found. The Levins’ standardized index indicated wider niche breadth for small skates, whereas larger skate specimens showed a narrow niche breadth with a specialization in fishes.