[1] Univ Roma Tor Vergata, Lab Expt Ecol & Aquaculture, Dept Biol, I-00133 Rome, Italy
[2] Univ Algarve, CCMAR, Faro, Portugal
[3] Univ Crete, Dept Biol, Iraklion, Crete, Greece
[4] IRTA SCR, Crta, St Carles De La, Spain
[5] NIFES, Bergen, Norway
[6] INRA, St Pee Sur Nivelle, France
[7] Univ Ghent, Dept Biol, B-9000 Ghent, Belgium