Preprint volume - SIBM
Preprint volume - SIBM
Preprint volume - SIBM
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Pre-print Volume –Invited presentations<br />
Topic 4: THE ELASMOBRANCHS<br />
G. RELINI, A. MANNINI, S. DE RANIERI 1 , I. BITETTO 2 , M.C. FOLLESA 3 ,<br />
V. GANCITANO 4 , C. MANFREDI 5 , L. CASCIARO 2 , L. SION 6<br />
Centro Biolmar - DIP.TE.RIS., Università di Genova, Viale Benedetto XV, 3 - 16132, Genova, Italia.<br />
biolmar@unige.it<br />
1 CIBM - Centro Interuniversitario di Biologia Marina, Viale N. Sauro, 4 - 57128 Livorno, Italia.<br />
2 COISPA Tecnologia & Ricerca, Stazione sperimentale per lo studio delle risorse del mare,<br />
Via dei Trulli, 18/20 - 70126 Torre a mare (BA), Italia.<br />
3 Dipartimento Biologia Animale ed Ecologia, Università di Cagliari, Viale Poetto, 1 - 09126 Cagliari, Italia.<br />
4 IAMC-CNR, Sezione Territoriale di Mazara, Via L. Vaccara, 61 - 91026 Mazara del Vallo (TP), Italia.<br />
5 Laboratorio di Biologia Marina e Pesca di Fano, Dip.to B.E.S., Univ. di Bologna,<br />
Viale Adriatico, 1/N - 61032 Fano (PU), Italia.<br />
6 Dipartimento di Zoologia, Università di Bari, Via Orabona, 4 - 70125 Bari, Italia.<br />
CHONDRICHTHYES CAUGHT DURING THE MEDITS SURVEYS<br />
IN THE ITALIAN WATERS<br />
I PESCI CARTILAGINEI PESCATI DURANTE LE CAMPAGNE MEDITS<br />
NELLE ACQUE ITALIANE<br />
Summary<br />
Data on Chondrichthyes fished during 16 surveys of MEDITS project carried out from<br />
1994 to 2009 on trawlable bottom up to 800m depth in all seas around Italy are<br />
presented and discussed.<br />
From the overall 7 GSAs involved during the 16 years surveys (10255 hauls) 40<br />
elasmobranch species including 23 rays and skates, 16 sharks and 1 chimaera have<br />
been identified (Tab.1).<br />
Only 9 species of which 5 sharks, occurred in all GSAs, and other 10 were present in<br />
85,7% of GSAs (6 on a total of 7).<br />
The highest number of species was found in Sicily Channel (30 species) the lowest (20<br />
species) in the South Adriatic Sea. Ten species of which 1 shark were found only in<br />
one GSA and five of them during one year only: they are Galeorhinus galeus (GSA10,<br />
1995 and 2001), Dasyatis centroura (GSA19, 2002) Pteroplatytrygon violacea<br />
(GSA10, 2000 and 2002), Gymnura altavela (GSA19, 2006) Pteromylaeus bovinus<br />
(GSA17, ten years), Dipturus batis (GSA9, 1996) Leucoraja melitensis (GSA16, all<br />
years excluding 1994 and 2003), Raja radula (GSA17, 1994), Rostroraja alba<br />
(GSA16, 1995, 2000, 2003, 2005, 2007, 2008 and 2009) and Rhinoptera marginata<br />
(GSA17, 1994).<br />
The number of species caught per year was 30 in 1995 and decreased to 23 in 1997<br />
than increased with some oscillation to 31 in 2008 and 2009.<br />
In each GSA and in each stratum the species with more than 20% occurrence (number<br />
of hauls in which the species was fished against the total hauls in the stratum<br />
considered) have been selected for data dealing with kg/km 2 , n/km 2 and mean weight<br />
(g). In GSA9 only 4 species have been considered Galeus melastomus showed biomass<br />
up to 100kg/km 2 and 850 n/km 2 . Lower catch were reached in GSA10. At GSA11 ten<br />
species were selected of which 6 are rays; Raja clavata reached 120 kg/km 2 and 130<br />
n/km 2 . Also GSA16 is rich in species (12) and rays (6) with quite high values of<br />
biomass and density. In GSA17 there were 4 species no rays, with low values. In<br />
GSA18 three species were selected Chimaera monstrosa, Etmopterus spinax and G.<br />
melastomus (up to 80 kg/km 2 ). In GSA19 only 3 species with lower values.<br />
41 st S.I.B.M. CONGRESS Rapallo (GE), 7-11 June 2010<br />
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