Among rays, it is noted that thornback ray Raja clavata is among the
species most commonly caught in the Mediterranean trawling [14].
R. clavata is rather frequently landed at Tunisian fishing sites, even if it
is locally considered as by-catch species [15]. R. clavata seems to be
among the few species for which production is increasing reaching
more than 400 tons in 2008 in theMediterranean and the Black Sea