Skip to main content
SpringerLink
Log in

Selectivity of flexible size-sorting grid in Mediterranean multispecies trawl fishery

  • Published:
Fisheries Science Aims and scope Submit manuscript

Abstract

The demersal multispecies trawl fishery in the western Mediterranean Sea has a poor selectivity; large numbers of juvenile fish are caught when using the legislated 40-mm diamond mesh cod end. The selectivity of a flexible sorting grid with 20-mm bar spacing (BS20) installed in front the conventional trawl cod end was investigated. The standard covered cod end method was used. Data was adequate for analyzing the selectivity of European hake Merluccius merluccius, poor cod Trisopterus minutus, greater forkbeard Phycis blennoides and Norway lobster Nephrops norvegicus. The selectivity of the 20-mm sorting grid was compared with the performance of 40-mm diamond (DM40) and square mesh (SM40) cod ends. The effect of a guiding funnel on the performance of the grid (BS20-f) was also explored. Finally, the potential changes in yield per recruit (Y/R) and biomass per recruit (B/R) after implementing a sorting grid were explored. An overall improvement in the 50% selection length (L 50) with all four species was substantial when comparing the BS20 to the DM40. Higher improvement in L 50s was achieved when the grid was equipped with the guiding funnel. When comparing the performance of the BS20-f to the SM40, there was no marked difference in L 50s. The Y/R and B/R, however, are substantially higher with BS20-f for poor cod and about the same for European hake. BS20 compared to SM40 achieved lower Y/R and B/R for all four species; the smallest difference was observed for Norway lobster. Further development is required if the sorting grid is to be introduced into commercial fisheries.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. Stergiou K, Politou C-Y, Christou E, Petrakis G. Selectivity experiments in the NE Mediterranean: the effect of trawl mesh size on species diversity and discards. ICES J. Mar. Sci. 1997; 54: 774–786.

    Article  Google Scholar 

  2. Guijarro B, Massuti E. Selectivity of diamond- and squaremesh codends in the deepwater crustacean trawl fishery off the Balearic Islands (western Mediterranean). ICES J. Mar. Sci. 2006; 63: 52–67.

    Article  Google Scholar 

  3. Carbonell A, Martin P, de Ranieri S. WEDIS team. Discards of the western Mediterranean trawl fleets. Rapp. Comm. Int. Mer. Médit. 1998; 35: 392–393.

    Google Scholar 

  4. Martín P, Sartor P, García-Rodríguez M. 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. 1999; 15: 24–28.

    Article  Google Scholar 

  5. Bahamon N, Sardà F, Suuronen P. Improvement of trawl selectivity in the NW Mediterranean demersal fishery by using a 40mm square mesh codend. Fish. Res. 2006; 81: 15–25.

    Article  Google Scholar 

  6. Recasens L, Lombarte A, Morales-Nin B, Torres G. Spatiotemporal variations in the population structure of the European hake in the northwestern Mediterranean. J. Fish Biol. 1998; 53: 387–401.

    Article  Google Scholar 

  7. Sardà F. Symptoms of overexploitation in the stock of the Norway lobster (Nephrops norvegicus) on the ‘Serola Bank’ (Western Mediterranean Sea off Barcelona). Sci. Mar. 1998; 62: 295–299.

    Google Scholar 

  8. Aldebert Y, Recasens L. Comparison of methods for stock assessment of European hake Merluccius merluccius in the Gulf of Lions (Northwestern Mediterranean. Aquat. Living Res. 1996; 9: 13–22.

    Article  Google Scholar 

  9. Caddy J. Some future perspectives for assessment and management of Mediterranean fisheries. Sci. Mar. 1993; 57: 121–130.

    Google Scholar 

  10. Sardà F, Conan GY, Fusté X. Selectivity of Norway lobster Nephrops norvegicus (L.) in the northwestern Mediterranean. Sci. Mar. 1993; 57: 167–174.

    Google Scholar 

  11. Stergiou KI, Petrakis G, Politou C-Y. Size selectivity of diamond and square mesh cod-ends for Nephrops norvegicus in the Aegean Sea. Fish. Res. 1997; 29: 203–209.

    Article  Google Scholar 

  12. Tokaç A, Lök A, Tosunoglu Z, Metin C, Ferro RST. Cod-end selectivities of a modified bottom trawl for three species in the Aegean Sea. Fish. Res. 1998; 39: 17–31.

    Article  Google Scholar 

  13. Sardà F, Molí B, Palomera I. Preservation of juvenile hake (Merluccius merluccius, L.) in the western Mediterranean demersal trawl fishery by using sorting grids. Sci. Mar. 2004; 68: 435–444.

    Google Scholar 

  14. Sardà F, Bahamon N, Sardà-Palomera F, Molí B. Commercial testing of a sorting grid to reduce catches of juvenile hake (Merluccius merluccius) in the western Mediterranean demersal trawl fishery. Aquat. Living Res. 2005; 18: 87–91.

    Article  Google Scholar 

  15. Sardà F, Bahamon N, Molí B, Sardà-Palomera F. The use of a square mesh and sorting grids to reduce catches of young fish and improve sustainability in a multispecies bottom trawl fishery in the NW Mediterranean Sea. Sci. Mar. 2006; 70: 347–353.

    Google Scholar 

  16. Larsen RB, Isaksen B. Size selectivity of rigid sorting grids in bottom trawls for Atlantic cod (Gadus morhua) and haddock (Melanogrammus aeglefinus). ICES Mar. Sci. Symp. 1993; 196: 178–182.

    Google Scholar 

  17. Suuronen P, Peres-Comaz JA, Lehtonen E, Tschernij V. Size related survival of Baltic herring (Clupea harengus) escaping through a rigid sorting grid and trawl codend meshes. ICES J. Mar. Sci. 1996; 53: 691–700.

    Article  Google Scholar 

  18. Graham N, O’Neill FG, Fryer RJ, Galbraith RD, Myklebust A. Selectivity of a 120 mm diamond cod-end and the effect of inserting a rigid grid or a square mesh pane. Fish. Res. 2004; 67: 151–161.

    Article  Google Scholar 

  19. Jørgensen T, Ingólfsson OA, Graham N, Isaksen B. Size selection of cod by rigid grids — Is anything gained compared to diamond mesh codends only?. Fish. Res. 2006 79: 337–348.

    Article  Google Scholar 

  20. Suuronen P, Lehtonen E, Jounela P Escape mortality of trawl caught Baltic cod (Gadus morhua) — the effect of water temperature, fish size and codend catch. Fish. Res. 2005; 71: 151–163.

    Article  Google Scholar 

  21. Loaec H, Morandeau F, Mellita M, Davies P. Engineering development of flexible selectivity grids for Nephrops. Fish. Res. 2006; 79: 210–218.

    Article  Google Scholar 

  22. Valdemarsen JW, Suuronen P. Modifying fishing gear to achieve ecosystem objectives. In: Sinclair M, Valdimarsson G (eds). Responsible Fisheries in the Marine Ecosystem. FAO and CABI International Publishing, Rome. 2003; 1–426.

    Google Scholar 

  23. Kuikka S, Suuronen P, Parmanne R. The impacts of increased codend mesh size on the northern Baltic herring fishery: ecosystem and market uncertainties. ICES J. Mar. Sci. 1995; 53: 723–730.

    Article  Google Scholar 

  24. Kvamme C, Froysa KG. Assessing the effects on stocks of selectivity changes in a fishery. Fish. Res. 2004; 69: 283–293.

    Article  Google Scholar 

  25. Bahamon N, Sardà F, Suuronen P. Potential benefits from improved selectivity in the northwest Mediterranean multispecies trawl fishery. ICES J. Mar. Sci. 2007; 64: 757–760.

    Article  Google Scholar 

  26. Bianchini ML, Ragonese S, Levi D. Management hypotheses to improve yield-per-recruit and economic returns in the red shrimp (Aristaemorpha foliacea) fishery of southern Sicily (Mediterranean Sea). J. Northw. Atl. Fish. Sci. 2003; 31: 233–243.

    Google Scholar 

  27. Tudela S. Ecosystem effects of fishing in the Mediterranean: an analysis of the major threats. GFCM Stud. Rev. 2004; 74: 1–44.

    Google Scholar 

  28. Rahikainen M, Kuikka S, Parmanne R. Modelling the effect of ecosystem change on spawning per recruit of Baltic herring. ICES J. Mar. Sci. 2003; 60: 94–109.

    Article  Google Scholar 

  29. Eigaard OR, Holst R. The effective selectivity of a composite gear for industrial fishing: a sorting grid in combination with a square mesh window. Fish. Res. 2004; 68: 99–112.

    Article  Google Scholar 

  30. Wileman D, Ferro R, Fonteyne R, Millar R. Manual of methods of measuring the selectivity of towed fishing gears. ICES Coop. Res. Rep. 1996; 215: 1–126.

    Google Scholar 

  31. Millar RB. Sampling from trawl gears used in size selectivity experiments. ICES J. Mar. Sci. 1994; 51: 293–298.

    Article  Google Scholar 

  32. Tokai T. Maximum likelihood parameter estimates of a mesh selectivity logistic model through SOLVER on MS-Excel. Bull. Jpn. Fish. Oceanogr. 1997; 61: 288–298.

    Google Scholar 

  33. Fryer RJ. A model of between-haul variation in selectivity. ICES J. Mar. Sci. 1991; 48: 281–290.

    Article  Google Scholar 

  34. Lleonart I, Salat J. VIT: Software for Fishery Analysis, User’s manual. FAO Computerized Information Series (Fisheries), 11. FAO, Rome, 1997.

    Google Scholar 

  35. Kvalsvik K, Huse I, Misund OA, Gamst K. Grid selection in the North Sea industrial trawl fishery for Norway pout: efficient size selection reduces. Fish. Res. 2006; 75: 248–263.

    Article  Google Scholar 

  36. Suuronen P. Mortality of fish escaning trawl gears. FAO Fisheries Technical Paper No. 478. FAO, Rome, 2005.

    Google Scholar 

  37. Petrakis G, Stergiou KI. Size selectivity of diamond and square mesh codends for four commercial Mediterranean fish species. ICES J. Mar. Sci. 1997; 54: 13–23.

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Institut de Ciències del Mar (CMIMA-CSIC), 08003, Barcelona, Spain

    Nixon Bahamon & Francesc Sardà

  2. Finnish Game and Fisheries Research Institute, FIN-00791, Helsinki, Finland

    Petri Suuronen

Authors
  1. Nixon Bahamon
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Francesc Sardà
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Petri Suuronen
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Nixon Bahamon.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Bahamon, N., Sardà, F. & Suuronen, P. Selectivity of flexible size-sorting grid in Mediterranean multispecies trawl fishery. Fish Sci 73, 1231–1240 (2007). https://doi.org/10.1111/j.1444-2906.2007.01460.x

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1111/j.1444-2906.2007.01460.x

Key Words

Search

Navigation