Feeding ecology of the transparent goby Aphia minuta (Pisces, Gobiidae) in the northwestern Adriatic Sea
Mario La Mesa, Diego Borme, Valentina Tirelli, Elena Di Poi, Sara Legovini and Serena Fonda Umani

The feeding ecology of the transparent goby Aphia minuta was examined in spring (May 2003) in the coastal waters off Comacchio, in the northwestern Adriatic Sea. Stomach content analysis indicated A. minuta to be a planktivorous species, feeding exclusively on pelagic invertebrates. The diet composition was dominated by the calanoid copepods Acartia clausi and Temora longicornis, followed in decreasing order of importance by other copepods (especially calanoids and Oncaea spp.) and larvae of decapods, polychaetes and bivalves. A. minuta exhibited a generalistic feeding strategy with a relatively broad niche width. Abundant taxa in the environment, such as A. clausi and T. longicornis, were seldom selected, whereas rare taxa, such as larvae of polychaetes and decapods, were highly selected. According to the observed ontogenetic shift in diet, small-size individuals relied preferentially on juvenile T. longicornis and Oncaea spp., whereas large-sized specimens consumed preferably A. clausi and calanoids. The positive relationship found between prey and fish size may help to mitigate the intraspecific competition for food resources.

Keywords: diet, feeding selectivity, transparent goby, copepods, Adriatic Sea
Contents of this volume Sci. Mar. 72(1) : 99-108 Back PDF
 
 
Please, send comments to
ICM (CSIC) - Passeig Marítim de la Barceloneta, 37-49. E-08003 Barcelona (Spain)