Preprint volume - SIBM

Pre-print Volume –Oral presentations
Topic 4: THE ELASMOBRANCHS
dominated by just one species, M. mustelus, with the other poorly represented. A
relative increase in M. mustelus and decrease in R. clavata and S. canicula has been
already observed in the Adriatic Sea (Jukic-Peladic et al., 2001), however in the fish
market surveys presented here some of the species previously reported for the Adriatic
were never found. At the fish market, a remarkable high proportion of the recorded
males were sexually immature. All these data together strongly indicate the nonsustainability
of elasmobranch fishery. The demographic models confirmed the
observed trends, predicting such a reduction of populations of M. mustelus and S.
canicula to be close to local extinction. However the models indicate also which
management strategy could give the best results. Banning the fishery of immature
individuals could, indeed, promote the recovery of the two populations. Such strategy
is feasible for elasmobranch: even if they are usually bycatch, in general high survival
rates of discarded individuals have been proved in different species.
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41 st S.I.B.M. CONGRESS Rapallo (GE), 7-11 June 2010
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