INVESTIGADORES
FERNANDEZ SEVERINI Melisa Daiana
congresos y reuniones científicas
Título:
Trophic spectrum of southern right whale Eubalaena australis by means of faecal analysis
Autor/es:
MENÉNDEZ MARÍA CLARA; BERASATEGUI ANABELA ANAHÍ; LINDNER MARÍA SOLEDAD; DIODATO SOLEDAD LORENA; FERNÁNDEZ SEVERINI MELISA DAIANA; HOFFMEYER MÓNICA SUSANA
Lugar:
Buenos Aires
Reunión:
Jornada; VIII Jornadas Multidisciplinarias de la Sociedad Argentina de Biologia; 2006
Institución organizadora:
Sociedad Argentina de Biología
Resumen:
Eubalaena australis lives in Nuevo Gulf from April to middle of December after a long migration from its feeding areas at high latitudes. It was thought that E. australis did not feed at this breeding zone at all. However, trophic behaviors of whales have been recently observed in both Nuevo and San José Gulfs, especially during springtime. Also, faeces of whales have been detected from whale-watching ships in the northeastern coasts of Nuevo Gulf. Faeces collected in October 2004were qualitatively analyzed as part of a large project aimed to evaluate the plankton availability related to whale’s trophic behavior. Faeces preserved in alcohol 70% were homogenized and three 5 ml-sub samples were taken to identify the strong remains of food items. They were treated with glycerine and methyl blue to improve the viewing of food remains under stereo and optical microscopes. Some of this material belonged to mandibles and coxae of Calanus australis and/or Calanoides carinatus, large Calanidae copepods that live in this zone. Pieces of crustaceans segments and antennae were also observed, some of which would probably correspond to euphausiids. In terms of relative abundance, copepod mandibles were the most abundant remains (>70%), non identified tegument parts were abundant (30-70 %) whereas copepod coxae and prosomes were scarse (<30%). These findings, obtained for the first time in Argentina, are a clear evidence f whale-foraging either in this breeding area or previously into the shelf. The foraging on large copepods agrees with that reported for the northern right whale Eubalaena gracilis on Calanus finmarchicus in the North West Atlantic feeding areas.