Implications for catch composition and revenue in changing from diamond to square mesh codends in the northeastern Mediterranean

Summary The objective of this study was to estimate the potential short-term economic loss as a result of replacing the commercial diamond codend with a square mesh codend, and to compare fish lengths captured in 40 mm square (S40) vs 44 mm commercial hand-woven diamond (CD44) mesh codends for red mullet (Mullus barbatus), common pandora (Pagellus erythrinus), bogue (Boops boops), European hake (Merluccius merluccius), axillary seabream (Pagellus acarne), and brushtooth lizardfish (Saurida undosquamis). A total of 20 hauls (10 hauls for S40 and 10 hauls for CD44) were conducted onboard a commercial trawler between 27 February and 11 April 2012 in Mersin Bay in the northeastern Mediterranean. Results showed that the 40 mm square mesh codend caught significantly fewer juveniles of all aforementioned species. However, when changing from the commercial diamond codend to the 40 mm square mesh codend the potential economic loss of revenue was found to be 40% in the study period, which covered the final 6 weeks of the fishing season.

[1]  P. He,et al.  A new shrimp trawl combination grid system that reduces small shrimp and finfish bycatch , 2013 .

[2]  H. Özbilgin,et al.  Selectivity of commercial compared to larger mesh and square mesh trawl codends for four fish species in the Aegean Sea , 2012 .

[3]  Junita Diana Karlsen,et al.  Escapement efficiency through a square mesh panel In: ICES (2012) Report of the ICES-FAO Working Group on Fishing Gear Technology and Fish Behaivour (WGFTFB), 23-27 April 2012, Lorient, France. ICES CM 2012/SSGESST:07 , 2012 .

[4]  H. Özbilgin,et al.  Mortalities of fish escaping from square and diamond mesh codends in the Aegean Sea , 2010 .

[5]  Z. Tosunoğlu,et al.  Selectivity of diamond (PA) and square (PE) mesh codends for commercially important fish species in the Antalya Bay, eastern Mediterranean , 2010 .

[6]  H. Özbilgin,et al.  Selectivity of conventional and alternative codend design for five fish species in the Aegean Sea , 2010 .

[7]  Alessandro Lucchetti,et al.  The effect of mesh configuration and codend circumference on selectivity in the Mediterranean trawl Nephrops fishery , 2010 .

[8]  René Holst,et al.  A simple statistical method for catch comparison studies , 2009 .

[9]  A. Lucchetti.  Comparison of diamond- and square-mesh codends in the hake (Merluccius merluccius L. 1758) trawl fishery of the Adriatic Sea (central Mediterranean) , 2008 .

[10]  C. Piccinetti,et al.  Size selection by diamond- and square-mesh codends in multi-species Mediterranean demersal trawl fisheries , 2008 .

[11]  Marta Coll,et al.  Improved trawl selectivity: effects on the ecosystem in the South Catalan Sea (NW Mediterranean) , 2008 .

[12]  N. Bahamon,et al.  Improvement of trawl selectivity in the NW Mediterranean demersal fishery by using a 40 mm square mesh codend , 2006 .

[13]  F. Ordines,et al.  Diamond vs. square mesh codend in a multi-species trawl fishery of the western Mediterranean: effects on catch composition, yield, size selectivity and discards , 2006 .

[14]  F. Sardà‐Palomera,et al.  The use of a square mesh codend and sorting grids to reduce catches of young fish and improve sustainability in a multispecies bottom trawl fishery in the Mediterranean , 2006 .

[15]  B. Guijarro,et al.  Selectivity of diamond- and square-mesh codends in the deepwater crustacean trawl fishery off the Balearic Islands (western Mediterranean) , 2006 .

[16]  H. Özbilgin,et al.  Selectivity of Standard, Narrow and Square Mesh Panel Trawl Codends for Hake (Merluccius merluccius) and Poor Cod (Trisopterus minutus capelanus) , 2005 .

[17]  H. Özbilgin,et al.  Effect of Square Mesh Escape Window on Codend Selectivity for Three Fish Species in the Aegean Sea , 2005 .

[18]  H. Özbilgin,et al.  Survival of red mullet (Mullus barbatus L., 1758) after escape from a trawl codend in the Aegean Sea , 2004 .

[19]  A. İşmen.  Maturity and Fecundity of Lizardfish (Saurida undosquamis Richardson, 1848) in İskenderun Bay (Eastern Mediterranean) , 2003 .

[20]  P. A. M. Stewart,et al.  A comparison of size selection of haddock and whiting by square and diamond mesh codends , 1988 .