Preprint volume - SIBM

More documents

Recommendations

Info

Pre-print Volume - Posters MANAGEMENT OF THE COASTAL ZONE COMMITEE G. RIZZO, T. MARČETA, V. MATOZZO, M. BRESSAN, M.G. MARIN Department of Biology, University of Padova, Via U. Bassi, 58/B – 35121 Padova, Italia. mgmar@bio.unipd.it NEW INSIGHT ON CLAM POPULATION (CHAMELEA GALLINA) IN THE CHIOGGIA DISTRICT: MORPHOMETRIC AND PHYSIOLOGICAL DATA CHAMELEA GALLINA NEL COMPARTIMENTO MARITTIMO DI CHIOGGIA: DATI MORFOMETRICI E FISIOLOGICI DI POPOLAZIONE Abstract – The population of the clam Chamelea gallina (Mollusca, Bivalvia) was studied in two sites of the Chioggia district, Caleri and Chioggia, from June 2009 to February 2010. Some preliminary results concerning spatial and temporal distribution, mortality, physiological and reproductive condition, recruitment and growth rate are presented. Key-words: Chamelea, Chioggia, North Adriatic, fisheries. Introduction – In the early 1980’s, Chamelea gallina landings were up to 100,000 t/yr along the western Adriatic Sea coasts (Froglia, 1989). Overexploitation, recruitment failure and mortality outbreaks have severely depleted clams stocks, leading to a reduction in total catches in Chioggia district, from almost 3000 t in 2007 to about 850 t in 2009 (CO.GE.VO., unpubl.). In this context, the research project “CLODIA” (Sviluppo sostenibile degli ambienti costieri) funded by Regione Veneto aims at providing new insight on spatial and temporal distribution, mortality, physiological and reproductive condition, recruitment and growth rate of the species, potentially useful for resource restocking and management. Some preliminary results are presented. Materials and methods – Clams were monthly sampled (from June 2009 to February 2010) along a 250 m transect parallel to the coast at Caleri (45°06.214 N; 12°20.660 E) and Chioggia (45°10.590 N; 12°19.670 E). A conventional dredge provided with a bag-shaped sampling mesh with a rigid mouth (40 cm width, 20 cm height) and a 9 mm mesh size was used to collect both juveniles (25 mm). Size frequency distribution in the dredged area was obtained measuring (antero-posterior axis), counting and weighting clams. Clam mortality was tentatively estimated by measuring weight percentage of empty shells. Percentages of mature animals were obtained by microscopic observation of smears of gonadal tissue. The condition index (CI), expressed as meat dry weight x 100/shell dry weight, was determined, and the survival-in-air test was performed. Results – In Tab. 1, C. gallina morphometric data are reported. On average, juveniles were more abundant at Caleri (49 clams per m 2 ) than at Chioggia (18 clams per m 2 ), whereas commercial size clams were less than 10 animals per m 2 at Caleri, and 5 animals per m 2 at Chioggia. A new age class (0+, mode=5 mm) was recruited at Caleri starting from September, with a mode shift to 7 mm in February. Clams of 15-22 mm shell length were the most abundant at Chioggia (1+, putatively). Average percentages of empty shells were 27% at Caleri and 33% at Chioggia, with a peak for both sites in January (53%). As for CI, no influence of the sampling site was recorded (mean CI=5.5), whereas a statistically significant influence of the sampling time (Kruskall- Wallis, p
Pre-print Volume - Posters MANAGEMENT OF THE COASTAL ZONE COMMITEE similar for clams from both sites, except for animals collected in July (Gehan- Wilcoxon test, p
Page 2 and 3:
41 st Congress of the Società Ital
Page 4 and 5:
Pre-print Volume ROGHI F., PARRAVIC
Page 6 and 7:
Pre-print Volume Topic 3 / Tema 3 I
Page 8 and 9:
Pre-print Volume CARLUCCI R., CAPEZ
Page 10 and 11:
Pre-print Volume PORPORATO E., MANG
Page 12 and 13:
Pre-print Volume SOCAL G., BERNARDI
Page 14 and 15:
Pre-print Volume - Opening keynote
Page 16 and 17:
Pre-print Volume - Opening keynote
Page 18 and 19:
Pre-print Volume - Introductory lec
Page 20 and 21:
Page 22 and 23:
Pre-print Volume -Lecture Topic 1:
Page 24 and 25:
Pre-print Volume -Lecture Topic 1:
Page 26 and 27:
Pre-print Volume - Invited presenta
Page 28 and 29:
Page 30 and 31:
Page 32 and 33:
Pre-print Volume - Oral presentatio
Page 34 and 35:
Page 36 and 37:
Page 38 and 39:
Page 40 and 41:
Page 42 and 43:
Page 44 and 45:
Page 46 and 47:
Page 48 and 49:
Page 50 and 51:
Page 52 and 53:
Page 54 and 55:
Page 56 and 57:
Page 58 and 59:
Page 60 and 61:
Page 62 and 63:
Page 64 and 65:
Page 66 and 67:
Page 68 and 69:
Page 70 and 71:
Page 72 and 73:
Page 74 and 75:
Page 76 and 77:
Page 78 and 79:
Page 80 and 81:
Pre-print Volume - Posters Topic 1:
Page 82 and 83:
Page 84 and 85:
Page 86 and 87:
Page 88 and 89:
Page 90 and 91:
Page 92 and 93:
Page 94 and 95:
Page 96 and 97:
Page 98 and 99:
Page 100 and 101:
Page 102 and 103:
Page 104 and 105:
Page 106 and 107:
Page 108 and 109:
Page 110 and 111:
Page 112 and 113:
Phytoplankton Groups kg C m -3 3.00
Page 114 and 115:
Page 116 and 117:
Page 118 and 119:
Page 120 and 121:
Page 122 and 123:
Page 124 and 125:
Page 126 and 127:
Page 128 and 129:
Page 130 and 131:
Page 132 and 133:
Page 134 and 135:
Page 136 and 137:
Page 138 and 139:
Page 140 and 141:
Page 142 and 143:
Page 144 and 145:
Page 146 and 147:
Page 148 and 149:
Page 150 and 151:
Page 152 and 153:
Page 154 and 155:
Page 156 and 157:
Page 158 and 159:
Page 160 and 161:
Genoa Sestri Levante Pre-print Volu
Page 162 and 163:
Page 164 and 165:
Page 166 and 167:
Page 168 and 169:
Page 170 and 171:
Page 172 and 173:
Page 174 and 175:
Page 176 and 177:
Page 178 and 179:
Page 180 and 181:
Page 182 and 183:
Page 184 and 185:
Page 186 and 187:
Page 188 and 189:
Page 190 and 191:
Page 192 and 193:
Page 194 and 195:
Pre-print Volume -Invited presentat
Page 196 and 197:
Page 198 and 199:
Page 200 and 201:
Pre-print Volume -Oral presentation
Page 202 and 203:
Page 204 and 205:
Page 206 and 207:
Page 208 and 209:
Page 210 and 211:
Page 212 and 213:
Page 214 and 215:
Page 216 and 217:
Page 218 and 219:
Page 220 and 221:
Pre-print Volume -Posters Topic 4:
Page 222 and 223:
15 % Scyliorhinus canicula 12 GRUND
Page 224 and 225:
Page 226 and 227:
Page 228 and 229:
Page 230 and 231:
Page 232 and 233:
Page 234 and 235:
Page 236 and 237:
Page 238 and 239:
Page 240 and 241:
Pre-print Volume - Posters AQUACULT
Page 242 and 243:
Page 244 and 245:
Page 246 and 247:
Page 248 and 249:
Page 250 and 251:
Page 252 and 253:
Page 254 and 255: Pre-print Volume - Posters AQUACULT
Page 256 and 257: Pre-print Volume - Posters AQUACULT
Page 258 and 259: Pre-print Volume BENTHOS COMMITEE B
Page 260 and 261: Pre-print Volume - Posters BENTHOS
Page 290 and 291: Pre-print Volume - Posters MANAGEME
Page 306 and 307: Pre-print Volume NECTON AND FISHERY
Page 308 and 309: Pre-print Volume -Posters NECTON AN
Page 334 and 335: Pre-print Volume - Posters PLANKTON
Page 346 and 347: Pre-print Volume VARIOUS TOPICS VAR
Page 348 and 349: Pre-print Volume - Posters VARIOUS
Page 354 and 355:
Pre-print Volume - Posters VARIOUS
Page 356 and 357:
Page 358 and 359:
Page 360 and 361:
Page 362 and 363:
Page 364 and 365:
Page 366 and 367:
Page 368 and 369:
Page 370 and 371:
Castellano M.......................
Page 372 and 373:
Maravelias C.......................
Page 374:
Traversi I. .......................
show all

Preprint volume - SIBM

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?