Comparison of the catches of European hake (Merluccius merluccius, L. 1758) taken with experimental gillnets of different mesh sizes in the northern Tyrrhenian Sea (western Mediterranean)
DOI:
https://doi.org/10.3989/scimar.2007.71n147Keywords:
European hake, gillnet, selectivity, Sechin method, SELECT method, western Mediterranean, artisanal fisheryAbstract
The impact of the gillnet fishery on Merluccius merluccius (European hake) was investigated in the northern Tyrrhenian Sea, western Mediterranean. Four mesh sizes were tested: 53, 62.5, 70 and 82 mm. Horse mackerel (Trachurus trachurus), hake and tub gurnard (Chelidonichthys lucerna) dominated the catches, from a minimum of 89% (82 mm mesh) to a maximum of 97.8% (70 mm) of the biomass caught. Efficiency of the four meshes was not significantly different with respect to the total hake catches. Selectivity on M. merluccius was assessed by Sechin and SELECT methods. Tangling was an important catch modality for hake, as evidenced by the results of the Sechin model which described only the first mode of the size distributions corresponding to the entangled specimens. SELECT showed that the bi-modal function gave the best adjustment to the length-frequency distributions; the modal catch sizes were 33, 39.2, 43.6 and 51 cm total length respectively for the 53, 62.5, 70 and 82 mm mesh sizes. Taking into account the size of first maturity for females (35.1 cm TL), 62.5 mm is the most adequate mesh for exploiting hake as it gives some protection to both immature specimens and large females.
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References
Aldebert, Y., L. Recasens and J. Lleonart. – 1993. Analysis of gear interactions in a hake fishery: The case of the Gulf of Lions (NW Mediterranean). Sci. Mar., 57(2-3): 207-217.
Belcari, P., S. De Ranieri, B. Reale, P. Sartor, M. Sbrana and C. Viva. – 2001. Spatial distribution and seasonal concentration of European hake’s juveniles, Merluccius merluccius (L. 1758) in the north Tyrrhenian Sea. Rapp. Comm. int. Mer Médit., 36: 238.
Berkeley, S., C. Chapman and S. Sogard. – 2004. Maternal age as a determinant of larval growth and survival in a marine fish, Sebastes melanops. Ecology, 85(5): 1258–1264. doi:10.1890/03-0706
Biagi, F. and M.N. Santos. – 2000. Hake set gears fisheries in Mediterranean and Eastern Atlantic waters. EU Project N° 97/0064, Final report: 1-165.
Biagi, F., S. De Ranieri and C. Viva. – 1994. Analysis of the growth of Merluccius merluccius (L.) in the northern Tyrrhenian Sea. EC DG XIV Study for assessment and management of fisheries in the western Mediterranean. Final Report, 2: 68-78.
Biagi, F., A. Cesarini, M. Sbrana and C. Viva. – 1995. Reproductive biology and fecundity of Merluccius merluccius (Linnaeus, 1758) in the Northern Tyrrhenian Sea. Rapp. Comm. int. Mer Médit., 34: 237.
Biagi, F., P. Sartor, G.D. Ardizzone, P. Belcari, A. Belluscio and F. Serena. – 2002. Analysis of demersal assemblages off the Tuscany and Latium coasts (north-western Mediterranean). Sci. Mar., 66(Suppl.2): 233-242.
Cannas, A. – 2001. Gli attrezzi da pesca in uso nelle marinerie italiane. Risultati del Programma MAPP, Unimar, Rome: 1-82.
Colloca, F., A. Belluscio and G.D. Ardizzone. – 2000. Sforzo di pesca, catture e gestione dello stock di nasello (Merluccius merluccius) in un’area del Tirreno Centrale. Biol. Mar. Medit., 7(1): 117-129.
Fabi, G., M. Sbrana, F. Biagi, F. Grati, I. Leonori and P. Sartor. – 2002. Set net selectivity for Lithognathus mormyrus (L., 1758), Diplodus annularis (L., 1758) and Mullus barbatus (L., 1758) in the Adriatic and Ligurian sea, (central and western Mediterranean). Fish. Res., 54(3): 375-388. doi:10.1016/S0165-7836(01)00270-3
FAO Marine Resources Service, Fishery Resources Division. – 2005. Review of the state of world marine fishery resources. FAO Fish. Tech. Pap., n° 457: 1-235.
Fonseca, P., R. Martins, A. Campos and P. Sobral. – 2005. Gill-net selectivity off Portuguese western coast. Fish. Res., 73: 323-339. doi:10.1016/j.fishres.2005.01.015
GFCM. – 2001. F.A.O General Fishery Council for the Mediterranean. Report of the twenty-sixth session. GFCM Sess. Rep., 26: 1-27.
Hislop, J.R.G. – 1984. A comparison of the reproductive tactics and strategies of cod, haddock, whiting and Norway pout in the North Sea. In: G.W. Potts and R.J. Wotton (eds.), Fish reproduction, pp. 311-329. Academic Press Inc, London.
Kawamura, G. – 1972. Gill net mesh selectivity curve developed from length-girth relationship. Bull. Jap. Soc. Sci., 38: 1119-1127.
Lleonart, J. – 2001. Impact of fishery and environment on hake recruitment in Northwestern Mediterranean – EU Project FAIR No. CT-97-3522, Final report: 1-680.
Lleonart, J. and F. Maynou. – 2003. Fish stock assessments in the Mediterranean: state of the art. Sci. Mar., 67(1): 37-49.
Martín, P., P. Sartor and M. Garcia-Rodriguez. – 1999. Exploitation patterns of the European hake Merluccius merluccius, red mullet Mullus barbatus and striped red mullet Mullus surmuletus in the western Mediterranean. J. Appl. Ichthyol., 15: 24-28. doi:10.1046/j.1439-0426.1999.00125.x
Millar, R.B. – 1994. Sampling from trawl gears used in size selectivity experiments. ICES J. Mar. Sci., 51: 293-298. doi:10.1006/jmsc.1994.1030
Millar, R. B. and R. Holst. – 1997. Estimation of gillnet and hook selectivity using log-linear models. ICES J. Mar. Sci., 54: 471-477. doi:10.1006/jmsc.1996.0196
Millar, R. B. and R.J. Fryer. – 1999. Estimating the size-selection curves of towed gears, traps, nets and hooks. Rev. Fish Biol. Fish., 9: 1-28. doi:10.1023/A:1008829909601
Palombi, S.R. – 2004. Why mothers matter. Nature, 430: 621-622. Reale, B., M. Sbrana and S. De Ranieri. – 1995. Population dynamics of Merluccius merluccius exploited by two different trawlnets in the Northern Tyrrhenian Sea. Rapp. Comm. int. Mer Médit., 34: 254.
Reis, E.G. and M.G. Pawson. – 1992. Determination of gill net selectivity for Bass (Dicentrarchus labrax L.) using commercial catch data. Fish. Res., 13: 173-187. doi:10.1016/0165-7836(92)90025-O
Sacchi, J. – 2001. Gillnet selectivity for Hake Merluccius merluccius and Red mullet Mullus surmuletus in the Mediterranean Sea. Sea Fisheries Science, supplement I. Proc. Inter. Commemorative Symp. 70th Anniversary of the Jpn. Soc. Fish. Sci., I: 371-375.
Santos, M. N., M. Gaspar, C.C. Monteiro and K. Erzini. – 2003. Gill net selectivity for European hake Merluccius merluccius from southern Portugal: implications for fishery management. Fish. Sci., 69: 873-882. doi:10.1046/j.1444-2906.2003.00702.x
Sartor, P., M. Sbrana and B. Reale. – 1996. Sfruttamento del nasello, Merluccius merluccius, (L. 1758) nell’Arcipelago Toscazo meridionale. Biol. Mar. Medit., 3(1): 576-578.
Sartor, P., L. Recasens, C. Viva and J. Lleonart. – 2001. Analysis of the impact of the fishery on the adult population of European Hake in the northwestern Mediterranean. Rapp. Comm. int. Mer Médit., 36: 321.
Sartor, P., M. Sbrana, B. Reale and P. Belcari. – 2003. Impact of the deep sea trawl fishery on demersal communities of the northern Tyrrhenian Sea (Western Mediterranean). J. Northwest Atl. Fish. Sci., 31: 275-284.
Sbrana, M. – 1995. Biologia e dinamica di popolazione di Merluccius merluccius (L.) (Pisces, Osteychthyes) del Mar Tirreno Settentrionale. Ph.D. thesis, University of Pisa.
Sechin, Yu.T. – 1969. A mathematical model for the selectivity curve of a gill net. Rybn. Khoz. 45 (9): 56-58. (Transl. from Russian by Int. Pac. Halibut Comm. Seattle, Wash.)
Siegel, S. and N.J. Castellan. – 1988. Non-parametric statistics for the behavioural sciences. Statistics Series, 2nd Edition, McGraw-Hill, New York.
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