Feeding habits of the Rio skate, Rioraja agassizi (Chondrichthyes: Rajidae), from off Uruguay and north Argentina

The feeding habits of the Rio skate, Rioraja agassizi, from off Uruguay and north Argentina were evaluated using a multiple-hypothesis modeling approach. Relationships between number of preys and sex, maturity stage, body size, season and region were assessed by building generalized linear models. R...

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Detalles Bibliográficos
Autores: Barbini, Santiago Aldo, Lucifora, Luis Omar
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2010
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/43184
Acceso en línea:http://hdl.handle.net/11336/43184
Access Level:acceso abierto
Palabra clave:Skates
Feeding Ecology
Diet Shifts
Southwest Atlantic
https://purl.org/becyt/ford/1.6
https://purl.org/becyt/ford/1
Descripción
Sumario:The feeding habits of the Rio skate, Rioraja agassizi, from off Uruguay and north Argentina were evaluated using a multiple-hypothesis modeling approach. Relationships between number of preys and sex, maturity stage, body size, season and region were assessed by building generalized linear models. R. agassizi fed mainly upon crustaceans (shrimps, crabs and amphipods) and teleosts, but also upon isopods, cumaceans, lancelets and polychaetes. Ontogenetic diet shifts were found: small R. agassizi consumed amphipods, cumaceans and isopods and large individuals on shrimps, crabs and teleosts. The consumption of crustaceans (amphipods, shrimps, crabs, isopods and cumaceans) was higher in the north (34° - 38°S) than in the south area (38° - 41°S). R. agassizi consumed more teleosts in the cold season and preyed more on lancelets in the warm season. Prey size increased with increasing body size of R. agassizi, but large individuals also consumed small prey. Ontogenetic shifts may be related to body size rather than other life-history traits. R. agassizi adapts its feeding habits in response to regional and seasonal changes.