Abstract
Catch composition and damage incurred to the populations of three crabs (Liocarcinus depurator, Medorippe lanata and Goneplax rhomboides), discarded by the “rapido” trawl fishery of Viareggio (eastern Ligurian Sea), was investigated. Data were collected on a monthly basis (January–December 2001) through embarks on board of a commercial fishing vessel, so as to reflect commercial fishing practice. The three species represented from 7 to 31% of the discarded biomass, varying with season. Density and biomass indices were characterised by a clear seasonality, each species showing a peak in a different period of the year. A six level scale, based on macroscopic external injuries was used to assess the damage sustained by each species after fishing and sorting operations. For the three species, very similar percentages (56–58%) of individuals were macroscopically intact, while inspection of damaged individuals revealed some differences in the distribution of injuries. G. rhomboides showed the highest proportion of serious damage, followed by L. depurator and M. lanata. The severity and frequency of damage was mainly correlated with interspecific and intraspecific (sexual dimorphism) morphological and behavioural characteristics. For example, specimens with longer and thin appendages, like males of G. rhomboides, seemed to be particularly vulnerable to the fishing and sorting operations; this could also explain the positive correlation between damage level and size found in this species. In M. lanata, small individuals proved to be more vulnerable, while for L. depurator no significant correlation was found between damage and size. Although these estimations did not take other injury typologies into account (e.g. internal and physiological damage), these results can be seen as a first indirect estimation of discard mortality for these species and can represent an important term of reference both for similar studies performed in other areas and for the monitoring of this fishery.
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References
Abelló, P., 1989. Reproduction and moulting in Liocarcinus depurator (Linnaeus, 1758) (Brachyura: Portunidae) in the Northwestern Mediterranean Sea. Scientia Marina 53:127–134.
Abelló, P., F. J. Valladares & A. Castellon, 1988. Analysis of the structure of decapod crustacean assemblages of the Catalan coast (North-West Mediterranean). Marine Biology 98: 39–49.
Alverson, D. L., M. H. Freeberg, J. G. Pope & S. A. Muravsky, 1994. A global assessment of fisheries bycatch and discards. FAO Fisheries Technical Papers 339: 1–233.
Bennett, D. B., 1973. The effect of limb loss and regeneration on the growth of the edible crab Cancer pagurus L. Journal of Experimental Marine Biology and Ecology 13:45–53.
Bergman, M. J. N. & M. Hup, 1992. Direct effects of beamt-rawling on macrofauna in a sandy sediment in the southern North Sea. ICES Journal of Marine Science 49: 5–11.
Bergmann, M. & P. G. Moore, 2001. Survival of decapod crustaceans discarded in the Nephrops fishery of the Clyde Sea area, Scotland. ICES Journal of Marine Science 58: 163–171.
Bergmann, M., D. J. Beare & P. G. Moore, 2001a. Damage sustained by epibenthic invertebrates discarded in the Nephrops fishery in the Clyde Sea area, Scotland. Journal of Sea Research 45: 105–118.
Bergmann, M., A. C. Taylor & P. G. Moore, 2001b. Physiological stress in decapod crustaceans (Munida rugosa and Liocarcinus depurator) discarded in the Clyde Nephrops fishery. Journal of Experimental Marine Biology and Ecology 259: 215–229.
Brugge, W. J. & M. J. Holden, 1991. Multispecies management: a manager’s point of view. ICES Marine Science Symposia 193: 353–358.
Carbonell, A., S. De Ranieri & P. Martín, 1997. Discards of the Western Mediterranean Trawl Fleets. EU Contract n. DG XIV-Med 94/027, Final report.
Fabi, G. & P. Sartor, 2002. Study on the Mixed-species of the Rapido Trawl Fishery along the Italian Coasts. EC Study Contract n. 99/051, Final report.
Farmer, M. J., D. T. Brewer & S. J. M. Blaber, 1998. Damage to selected fish species escaping from prawn trawl cod-ends: a comparison between square-mesh and diamond mesh. Fisheries Research 38: 73–81.
Fernández, L., E. González-Gurriaraán & J. Freire, 1991. Population biology of Liocarcinus depurator (Brachyura: Portunidae) in mussel raft culture areas in the Ría de Arousa (Galicia, NW Spain). Journal of the Marine Biological Association of the United Kingdom 71: 375–390.
Giovanardi, O., F. Pranovi & G. Franceschini, 1998. “Rapido” trawl-fishing in the northern Adriatic: preliminary observations on effects on macrobenthic communities. Acta Adriatica 39: 37–52.
Gislason, H., 1994. Ecosystem effects of fishing activities in the North Sea. Marine Pollution Bulletin 29: 520–527.
Hall, S. J., 1999. The Effects of Fishing on Marine Ecosystems and Communities. Blackwell, Oxford.
Hall-Spencer, J. M., C. Froglia, R. J. A. Atkinson & P. J. Moore, 1999. The impact of rapido trawling for scallops, Pecten jacobaeus (L.), on the benthos of the Gulf of Venice. ICES Journal of Marine Science 56: 111–124.
Jennings, S. & M. J. Kaiser, 1998. The effects of fishing on marine ecosystems. Advances in Marine Biology 34: 201–352.
Kaiser, M. J., 1996. Starfish damage as an indicator of trawling intensity. Marine Ecology Progress Series 134: 303–307.
Kaiser, M. J. & B. E. Spencer, 1995. Survival of by-catch from a beam trawl. Marine Ecology Progress Series 126: 31–38.
Kaiser, M. J. & S. J. De Groot, (eds.), 2000. The Effects of Fishing on Non-target Species and Habitats. Blackwell, Oxford.
Kaiser, M. J., D. B. Edwards, P. J. Armstrong, K. Radford, N. E. L. Lough, R. P. Flatt & H. D. Jones, 1998. Changes in megafaunal benthic communities in different habitats after trawling disturbance. ICES Journal of Marine Science 55: 353–361.
MacDonald, D. S., M. Little, N. C. Eno & K. Hiscock, 1996. Disturbance of benthic species by fishing activities: a sensitivity index. Aquatic Conservation 6: 257–268.
Machias, A., V. Vassilopoulou, D. Vatsos, P. Bekas, A. Kallianiotis, C. Papaconstantinou & N. Tsimenides, 2001. Bottom trawl discards in the northeastern Mediterranean Sea. Fisheries Research 53: 181–195.
Mori, M. & P. Zunino, 1987. Aspects of the Libiology of Liocarcinus depurator (L.) in the Ligurian Sea. Investigación Pesquera 51: 135–145.
Pranovi, F., S. Raichevich, G. Franceschini, P. Torricelli & O. Giovanardi, 2001. Discard analysis and damage to nontarget species in the “rapido” trawl fishery. Marine Biology 139: 863–875.
Ramsay, K. & M. J. Kaiser, 1998. Demersal fishing disturbance increases predation risk for whelks (Buccinum undatum L.). Journal of Sea Research 39: 299–304.
Rice, J. & H. Gislason, 1996. Patterns of change in the size spectra of numbers and diversity of the North Sea fish assemblage, as reflected in surveys and models. ICES Journal of Marine Science 53: 1214–1225.
Sanchez, P., M. Demestre, M. Ramon & M. J. Kaiser, 2000. The impact of otter trawling on mud communities in the northwestern Mediterranean. ICES Journal of Marine Science 57: 1352–1358.
Siegel, S., 1956. Nonparametric Statistics for Behavioural Sciences. McGraw-Hill Book Company, Inc, New York.
Veale, L. O., A. S. Hill, S. J. Hawkins & A. R. Brand, 2001. Distribution and damage to the by-catch assemblages of the northern Irish Sea scallop dredge fisheries. Journal of the Marine Biological Association of the United Kingdom 81: 85–96.
Wassenberg, T. J. & B. J. Hill, 1989. The effect of trawling and subsequent handling on the survival rates of the by-catch of prawn trawler in Moreton Bay, Australia. Fisheries Research 7: 99–110.
Wassenberg, T. J. & B. J. Hill, 1993. Selection of the appropriate duration of experiments to measure the survival of animals discarded from trawlers. Fisheries Research 17:343–352
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Sartor, P., Francesconi, B., Rossetti, I., De Ranieri, S. (2006). Catch composition and damage incurred to crabs discarded from the eastern Ligurian Sea “rapido” trawl fishery. In: Thessalou-Legaki, M. (eds) Issues of Decapod Crustacean Biology. Developments in Hydrobiology, vol 184. Springer, Dordrecht. https://doi.org/10.1007/1-4020-4756-8_15
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DOI: https://doi.org/10.1007/1-4020-4756-8_15
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