ORIGINAL ARTICLE Diet and prey selectivity of the red mullet, Mullus barbatus (Pisces: Mullidae), from the southern Tyrrhenian Sea: the role of the surf zone as a feeding ground VALENTINA ESPOSITO 1 *, FRANCO ANDALORO 2 , DANIELA BIANCA 2 , ANTONINO NATALOTTO 3 , TERESA ROMEO 1 , GIANFRANCO SCOTTI 1 & LUCA CASTRIOTA 2 1 ISPRA (Institute for Environmental Protection and Research), Laboratory of Milazzo, Milazzo, Italy, 2 ISPRA, Palermo, Italy, and 3 University of Messina, Department of Animal Biology and Marine Ecology, Messina, Italy Abstract The diet and prey selectivity of the red mullet, Mullus barbatus, on a sandy bottom of the Tyrrhenian Sea were examined in respect to season, size and depth, focusing on the use of the surf zone as a feeding ground. Stomach contents of 99 specimens collected by beach seine (in the surf zone) and 568 specimens collected by trawl net (at 10, 20 and 30 m depths) were analysed. The overall diet of M. barbatus was dominated by crustaceans, mainly gammarids, while molluscs and polychaetes were secondary prey taxa. The diet composition of red mullet at each specific depth was related to the availability of prey in the benthic community: mysids were mostly preyed on in the surf zone, while gammarids, decapods and copepods were the principal crustacean prey organisms at other investigated depths. Red mullet in the surf zone mainly preyed on mysids and bivalves in summer and on cumaceans, gammarids and polychaetes in winter. At the other depths, seasonal variation in diet composition reflected the fluctuations of gammarid abundance in the environment; no differences in diet by size were detected. As a result, M. barbatus in the southern Tyrrhenian Sea can be considered as an opportunistic predator of benthic organisms, relying predominantly on crustaceans. Key words: Diet, prey selection, Mullus barbatus, benthos, surf zone, Mediterranean Sea, Sicily Introduction Red mullet, Mullus barbatus Linnaeus, 1758, is a common demersal fish living on sandy and muddy bottoms of the continental shelf at depths down to 200 m (Tserpes et al. 2002). It is distributed all across the Mediterranean basin, including the Black Sea and the Eastern Atlantic along the European and African coasts (Hureau 1986; Bauchot 1987; Lombarte et al. 2000). It reaches a maximum standard length of 30 cm (Hureau 1986) and reproduces from April to September with a peak in May (Sieli et al. 2011). In the Mediterranean Sea, red mullet is one of the most important demersal fishes in commercial terms and is one of the principal target species of trammel net and bottom trawl fisheries (Voliani 1999; Tserpes et al. 2002). The fishing activity is mostly directed towards young specimens (e.g. Stergiou et al. 1992; Demestre et al. 1997). Along Italian coasts, red mullet is mainly caught by bottom trawling, whereas trammel and gill net catches are negligible (Voliani 1999). Particularly for the southern Tyrrhenian Sea trawl fisheries, average catches of approximately 616 t year 1 from 2002 to 2007 are reported (Spedicato et al. 2010). Due to its high commercial value, several research- ers have investigated its feeding habits in the Medi- terranean Sea (e.g. Machias & Labropoulou 2002; Aguirre & Sanchez 2005; Bautista-Vega et al. 2008). These studies reported that red mullet is a benthivor- ous fish, feeding mainly on polychaetes but also on crustaceans and molluscs. Like other goatfishes, it can detect surface and subsurface organisms via its characteristic barbels, rich in chemoreceptors; it then *Correspondence: Valentina Esposito, ISPRA (Institute for Environmental Protection and Research), Laboratory of Milazzo, Via dei Mille 44, 98057 Milazzo (ME), Italy. E-mail: espositovalentina@hotmail.com Published in collaboration with the Institute of Marine Research, Norway Marine Biology Research, 2014 Vol. 10, No. 2, 167178, http://dx.doi.org/10.1080/17451000.2013.797585 (Accepted 26 March 2013; Published Online 18 September 2013) # 2014 Taylor & Francis Downloaded by [Valentina Esposito] at 00:29 02 October 2013