IIMYC   23581
INSTITUTO DE INVESTIGACIONES MARINAS Y COSTERAS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Feeding of the intertidal crab Neohelice (=Chasmagnathus) granulata: The influence of diurnal phase, habitat, season and tidal regime
Autor/es:
LANCIA, JUAN; BAS, CLAUDIA; LUPPI, TOMAS; AGUSTINA MÉNDEZ CASARIEGO; KITTLEIN, MARCELO; SPIVAK, EDUARDO
Lugar:
Mar del Plata
Reunión:
Conferencia; CERF 2012; 2012
Institución organizadora:
Coastal and estuaries research federation
Resumen:
Neohelice granulata (Brachyura, Varunidae) is a semi-terrestrial burrowing crab inhabiting intertidal areas in the South-Western Atlantic coast. It occupies different habitats, from bare low intertidal mudflats to high intertidal saltmarshes, and from fine, organic matter rich sediment, to very coarse sediment with low content of organic matter. The feeding activity and food items consumed by crabs from different habitats were studied in three sites with diverse sets of physical and biological conditions. The relationship among feeding activity, food items consumed, tidal, daily and seasonal cycles and physical characteristics of each site and intertidal zone were evaluated. Feeding activity of adult N. granulata varied according to the spatial and/or temporal changes in some natural cycles and was modulated by a complex interaction of factors. In general, males and non ovigerous females fed after darkness and during submersion periods but also after emersion periods if sediment and burrows remained wet. Ovigerous females almost never fed. This species has a dual mode of feeding: predominantly herbivory (live plants or plant litter in salt marshes) or deposit feeder (superficial sediment and detritus in mudflats). The quantity and quality of ingested food varied among sites and a trend to omnivory (including algae and conspecifics in the diet) related with the low quality of resources was detected.