Scientia Marina, Vol 78, No 2 (2014)

Preliminary evaluation of landings and discards of the Turkish bottom trawl fishery in the northeastern Aegean Sea (eastern Mediterranean)


https://doi.org/10.3989/scimar.03942.30B

Çetin Keskin
University of Istanbul, Faculty of Fisheries , Turkey

Francesc Ordines
Instituto Español de Oceanografía, Centre Oceanogràfic de les Balears , Spain

Celal Ates
University of Muğla Sıtkı Koçman, Fisheries Faculty , Turkey

Joan Moranta
Instituto Español de Oceanografía, Centre Oceanogràfic de les Balears , Spain

Enric Massutí
Instituto Español de Oceanografía, Centre Oceanogràfic de les Balears , Spain

Abstract


This short-term study on commercial discards was carried out in fishing grounds around Gökçeada Island in the northeastern Aegean Sea, a geographic area where fisheries information is rather limited. A total of 28 bottom trawls were performed between 70 and 410 m depth from December 2009 to February 2010. All the samples were collected on board a commercial trawler under commercial fishing conditions. A total of 3143 kg of biomass was caught in 28 valid hauls. Landings accounted for about 67% of the total catch while the remaining 33% was discarded. Fish species comprised 85% of the total catch and their composition could be divided into four main groups related to depth: shallow shelf (70 to 88 m), deep shelf (155 to 180 m), shelf break (196 to 276 m), and upper slope (307 to 410 m). Fish dominated the abundance and biomass of both landings and discards in all bathymetric strata. Echinoderms also accounted for a large proportion of the discards. Mean total catches varied between 78.4 kg/h on the shallow shelf and 38.1 kg/h on the shelf break with no differences in the landing biomass between groups, but with slightly higher discards over the shallow shelf. Taking into account the preliminary nature of the findings, based on a short-term analysis, the minimum mesh size and minimum landing size currently applied in the Turkish bottom trawl fishery are not sufficient to reduce discards and to protect juveniles of commercially important species in the northeastern Aegean Sea.

Keywords


bottom trawl; catch composition; landings; discards; length-frequency; eastern Mediterranean

Full Text:


HTML PDF XML

References


Anonymous 2012. Commercial fish catching regulation in seas and inland waters in 2012-2016 fishing period: Circular Nº 2012/65. Republic of Turkey, Ministry of Food, Agriculture and Livestock, General Directorate of Fisheries and Aquaculture.

Bayhan E., Ergin M., Temel A. et al. 2001. Sedimentology and mineralogy of surficial bottom deposits from the Aegean-Çanakkale-Marmara transition (Eastern Mediterranean): Effects of marine and terrestrial factors. Mar. Geol. 175: 297-315. http://dx.doi.org/10.1016/S0025-3227(01)00142-6

Benli H.A., Cihangir B., Bizsel K.C. 1999. Investigation on demersal fishery resources in the Aegean Sea. Istanbul University Fisheries Faculty, Journal of Aquatic Products (Special Print), 301-370.

Bilgin S., Ozen O., ?smen A. et al. 2009. Bathymetric Distribution, Seasonal Growth and Mortality of the Deep-Water Rose Shrimp Parapenaeus longirostris (Decapoda: Penaeidae) in an Unexploited Stock in Saros Bay, Aegean Sea. J. Anim. Vet. Ad. 8(11): 2404-2417.

Caddy J.F. 2009. Practical issues in choosing a framework for resource assessment and management of Mediterranean and Black Sea fisheries. Medit. Mar. Sci. 10: 83-119. http://dx.doi.org/10.12681/mms.124

Carbonell A., Martín P., De Ranieri S. et al. 1998. Discards of the western Mediterranean trawl fleets. Rapp. Comm. int. Mer Médit. 35: 292-293.

Carney R.S. 2005. Zonation of deep biota on continental margins. Oceanogr. Mar. Biol. Ann. Rev. 43: 211-278. http://dx.doi.org/10.1201/9781420037449.ch6

Cartes J.E., Sardà F. 1993. Zonation of deep-sea decapod fauna in the Catalan Sea (Western Mediterranean). Mar. Ecol. Prog. Ser. 94: 27-34. http://dx.doi.org/10.3354/meps094027

Chilari A., Petrakis G., Evaggelos T. 2006. Aspects of the biology of the blackspot seabream (Pagellus bogaraveo) in the Ionian Sea, Greece. Fish. Res. 77: 84-91. http://dx.doi.org/10.1016/j.fishres.2005.08.003

Clarke K.R., Warwick R.M. 2001. Change in Marine Communities: An Approach to Statistical Analysis and Interpretation. 2nd ed. PRIMER-E: Plymouth.

Coker T., Turkoglu M., Satilmis H.H. 2008. Seasonal Distribution of some Fish Eggs and Larvae, and Potential Contribution of Some Large Scale Pelagic Fish Species in Saros Bay, Turkey. In Çanakkale Values Symposiums (ÇIDS), Gelibolu Bulletin Book, 27-28 August 2008, Gelibolu, Çanakkale, Turkey. 329-330 pp. (in Turkish).

Coll M., Palomera I., Tudela S. et al. 2006. Trophic flows, ecosystem structure and fishing impacts in the South Catalan Sea, Northwestern Mediterranean. J. Mar. Syst. 59: 63-96. http://dx.doi.org/10.1016/j.jmarsys.2005.09.001

Damalas D., Vassilopoulou V. 2011. Chondrichthyan by-catch and discards in the demersal trawl fishery of the central Aegean Sea (Eastern Mediterranean). Fish. Res. 108: 142-152. http://dx.doi.org/10.1016/j.fishres.2010.12.012

Damalas D., Maravelias C.D., Katsanevakis S. et al. 2010. Seasonal abundance of non-commercial demersal fish in the eastern Mediterranean Sea in relation to hydrographic and sediment characteristics. Est. Coast. Shelf Sci. 89: 107-118. http://dx.doi.org/10.1016/j.ecss.2010.06.002

Davies R.W.D., Cripps S.J., Nickson A. et al. 2009. Defining and estimating global marine fisheries bycatch. Mar. Policy 33: 661-672. http://dx.doi.org/10.1016/j.marpol.2009.01.003

D'Onghia G., Tursi A., Maiorano P. et al. 1998. Demersal fish assemblages from the bathyal grounds of the Ionian Sea (middle-eastern Mediterranean). Ital. J. Zool. 65: 287-292. http://dx.doi.org/10.1080/11250009809386834

D'Onghia G., Carlucci R., Maiorano P. et al. 2003. Discards from deep-water bottom trawling in the eastern-central Mediterranean Sea and effects of mesh size changes. J. Northwest Atl. Fish. Soc. 31: 245-262.

Duruer E.Ç., Tosuno?lu Z. 2012. Comparison of the discard characteristics of diamond and square mesh codends in the Aegean Sea trawl fishery. Ege J. Fish. Aqua. Sci. 29(1): 31-34.

Estácio S., Mendonça A., Krug H. et al. 2001. Aspects of the reproduction of six exploited demersal fish species in the Azores archipelago, Arquipélago. Life Mar. Sci. (Suppl. 2 Part B): 83-94.

European Commission 2007. Turkey 2007 Progress Report. Accompanying the Communication from the Commission to the European Parliament and the Council. Enlargement Strategy and Main Challenges 2007-2008 {COM(2007) 663 final}. Commission Staff Working Document. Brussels, 6.11.2007, SEC(2007) 1436, 82 pp.

European Commission 2011. Reform of the Common Fisheries Policy. Communication from the Commission to the European Parliament, the Council, the European Economic and Social Committee and the Committee of the Regions. Brussels, 13.7.2011, COM(2011) 417 final, 10 pp.

Garibaldi L., Caddy J.F. 1998. Biogeographic characterization of Mediterranean and Black Sea faunal provinces using GIS procedures. Ocean Coast. Manage. 39: 211-227. http://dx.doi.org/10.1016/S0964-5691(98)00008-8

Gislason H., Sinclair M., Sainsbury K. et al. 2000. Symposium overview: incorporating ecosystem objectives within fisheries management. ICES J. Mar. Sci. 57: 468-475. http://dx.doi.org/10.1006/jmsc.2000.0741

Guijarro B., Massutí E. 2006. Selectivity of diamond- and square-mesh codends in the deep water crustacean trawl fishery off the Balearic Islands (western Mediterranean). ICES J. Mar. Sci. 63: 52-67. http://dx.doi.org/10.1016/j.icesjms.2005.08.011

Harmelin-Vivien M., Kelig M., Xavier B. et al. 2012. Possible link between prey quality, condition and growth of juvenile hake (Merluccius merluccius) in the Gulf of Lions (NW Mediterranean). Cybium 36(2): 323-328.

Ignatiades L., Psarra S., Zervakis V. et al. 2002. Phytoplankton size-based dynamics in the Aegean Sea (Eastern Mediterranean). J. Marine Syst. 36: 11-28. http://dx.doi.org/10.1016/S0924-7963(02)00132-X

Ismen A., Özekinci U., Özen Ö. et al. 2010. Saroz Körfezi (Kuzey Ege Denizi) Demersal Balıklarının Biyo-Ekolojisi ve Populasyon Dinami?inin Belirlenmesi Proje Raporu (Tu.bitak, Çaydag -106Y035). Ankara. 358 pp. (in Turkish)

Jennings S., Kaiser M.J. 1998. The effects of fishing on marine ecosystems. Ad. Mar. Biol. 34: 201-352. http://dx.doi.org/10.1016/S0065-2881(08)60212-6

Kallianiotis A., Sophronidis K., Vidoris P. et al. 2000. Demersal fish and megafaunal assemblages on the Cretan continental shelf and slope (NE Mediterranean): seasonal variation in species density, biomass diversity. Prog. Oceanog. 46: 429-455. http://dx.doi.org/10.1016/S0079-6611(00)00028-8

Kallianiotis A., Vidoris P., Sylaios G. 2004. Fish species assemblages and geographical sub-areas in the North Aegean Sea, Greece. Fish. Res. 68: 171-187. http://dx.doi.org/10.1016/j.fishres.2003.12.007

Kara O.F., Gurbet R. 1999. Investigation on industrial fishery of the Aegean Sea. The Republic of Turkey, Ministry of Agriculture and Rural Affairs, Bodrum. No: 5, 135 pp. (In Turkish)

Katsanevakis S, Maravelias, C.D., Damalas, D. et al. 2009. Spatiotemporal distribution and habitat use of commercial demersal species in the eastern Mediterranean Sea. Fish. Oceanogr. 18(6): 439-457. http://dx.doi.org/10.1111/j.1365-2419.2009.00523.x

Katsanevakis S., Maravelias, C.D. 2009. Bathymetric distribution of sixteen demersal fish in the Aegean and Ionian Seas, based on generalized additive modelling. Fish. Sci. 75(1): 13-23. http://dx.doi.org/10.1007/s12562-008-0033-5

Kelleher K. 2005. Discards in the world's marine fisheries. An update. FAO Fisheries Technical Paper. No. 470. Rome, FAO. 2005. 131 pp. Includes a CD-ROM.

Keskin C., Ordines F., Guijarro B. et al. 2011a. Comparison of fish assemblages between the Sea of Marmara and the Aegean Sea (north-eastern Mediterranean). J. Mar. Biol. Assoc. U.K. 91: 1307-1318. http://dx.doi.org/10.1017/S0025315410002213

Keskin Ç., Turan C., Ergu.den D. 2011b. Distribution of the demersal fishes on the continental shelves of the Levantine and North Aegean Seas (Eastern Mediterranean). TrJFAS 11(3): 413-423.

Klaoudatos D., Kapiris C., Conides A. et al. 2010. Assessment of demersal distribution between two fishing areas in North and Central Greece. Int. Aquat. Res. (Special Issue of Aqua Medit 2010 Conference, Greece) 2: 143-154.

Kınacıgıl H.T., ?lkyaz A.T. 2012. Aegean Sea Fisheries. In: A. Tokaç, A.C. Gu.cu., B. O¨ztu¨rk, (eds). The State of the Turkish Fisheries. Turkish Marine Research Foundation, Istanbul, Turkey. pp. 233-241.

Koral H., O¨ztu¨rk H., Hanilçi N. 2008. Tectonically induced coastal uplift mechanism of Gökçeada Island, Northern Aegean Sea, Turkey. Quatern. Int. Ko?ar ?. 2009. Tu.rkiye'de Balıkçılık ?statistiklerinin. yile.tirilmesi ve Avrupa Birli?i Uyum Su.reci. (Improvement Turkish fishery statistics and EU accession process). E.U.J. Fish. Aquat. Sci. 26 (2): 153-158.

Krug H.M. 1998. Variation in the reproductive cycle of the blackspot seabream, Pagellus bogaraveo (Bru.nnich, 1768) in the Azores, Arquipélago. Life Mar. Sci. 16A: 37-47

Labropoulou A., Papaconstantinou C. 2000. Community structure of deep-sea demersal fish in the North Aegean Sea (Northeastern Mediterranean). Hydrobiologia 440: 281-296. http://dx.doi.org/10.1023/A:1004199917299

Labropoulou A., Papaconstantinou C. 2004. Community structure and diversity of demersal fish assemblages: the role of fishery. Sci. Mar. 68(Suppl. 1): 215-226.

Labropoulou A., Papaconstantinou C. 2005. Effects of fishing on community structure of demersal fish assemblages. Bel. J. Zool. 135(2): 191-197.

Machias A., Vassilopoulou V., Vatsos D. et al. 2001. Bottom trawl discards in the northeastern Mediterranean Sea. Fish. Res. 53: 181-195. http://dx.doi.org/10.1016/S0165-7836(00)00298-8

Machias A., Maiorano P., Vassilopoulou V. et al. 2004. Sizes of discarded commercial species in the eastern central Mediterranean Sea. Fish. Res. 66: 213-222. http://dx.doi.org/10.1016/S0165-7836(03)00202-9

Maravelias C.D., Tserpes G., Pantazi M. et al. 2012. Habitat Selection and Temporal Abundance Fluctuations of Demersal Cartilaginous Species in the Aegean Sea (Eastern Mediterranean). PLoS One 7(4), e35474. http://dx.doi.org/10.1371/journal.pone.0035474 PMid:22536389 PMCid:PMC3335001

Massutí E., Re-ones O., Carbonell A. et al. 1996. Demersal fish communities exploited on the continental shelf and slope off Majorca (Balearic Islands, NW Mediterranean). Vie Milieu 46: 45-55.

Massutí E., Re-ones O. 2005. Demersal resource assemblages in the trawl fishing grounds of the Balearic Islands (western Mediterranean). Sci. Mar. 69(1): 167-181.

Moranta J., Stefanescu C., Massutí E. et al. 1998. Fish community structure and depth-related trends on the continental slope of the Balearic Islands (Algerian basin, western Mediterranean). Mar.Ecol. Prog. Ser. 171: 247-259. http://dx.doi.org/10.3354/meps171247

Moranta J., Massutí E., Morales-Nin B. 2000. Fish catch composition of the deep-sea decapod crustacean fisheries in the Balearic Islands (western Mediterranean). Fish. Res. 45: 253-264. http://dx.doi.org/10.1016/S0165-7836(99)00119-8

Moranta J., Quetglas A., Massutí E. et al. 2008. Research trends on demersal fisheries oceanography in the Mediterranean. In L.P. Mertens (ed.), Biological Oceanography Research Trends. Nova Science Publishers, New York. PMCid:PMC2632040

Ordines F., Massutí E., Guijarro B. et al. 2006. Diamond vs. square mesh codend in a multi-species trawl fishery of the western Mediterranean: effects on catch composition, yield, size selectivity and discards. Aquat. Living Resour. 19: 329-338. http://dx.doi.org/10.1051/alr:2007003

Özbilgin Y.D., Tosuo?lu Z., Özbilgin H. 2006. By-catch in a 40 mm PE demersal trawl codend. J. Anim. Vet. Ad. 30: 179-185.

Pazi I. 2008 Water mass properties and chemical characteristics in the Saros Gulf, Northeast Aegean Sea (Eastern Mediterranean). J. Mar. Syst. 74: 698-710. http://dx.doi.org/10.1016/j.jmarsys.2008.07.002

Petrakis G., Stergiou K.I. 1997. Size selectivity of diamond and square mesh codends for four commercial Mediterranean fish species. ICES J. Mar. Sci. 54: 13-23. http://dx.doi.org/10.1006/jmsc.1996.0172

Pielou E.C. 1969. An introduction to Mathematical Ecology. Wiley, Sons, New York.

Piet G.J., Jennings S. 2005. Response of potential fish community indicators to fishing. ICES J. Mar. Sci. 62: 214-225. http://dx.doi.org/10.1016/j.icesjms.2004.09.007

REC.CM-GFCM/33/2009/2. On the minimum mesh size in the codend of demersal trawl nets. http://151.1.154.86/gfcmwebsite/Docs/RecRes/REC.CM-GFCM_33_2009_2.pdf

Sarı E., Ça?atay M.N. 2001. Distributions of heavy metals in the surface sediments of the Gulf of Saros, NE Aegean Sea. Environ. Int. 26: 169-173. http://dx.doi.org/10.1016/S0160-4120(00)00097-0

Sánchez P., Demestre M., Martín P. 2004. Characterization of the discards generated by bottom trawling in the Northwestern Mediterranean. Fish. Res. 67: 71-80. http://dx.doi.org/10.1016/j.fishres.2003.08.004

Sánchez P., Sartor P., Recasens L. et al. 2007. Trawl catch composition during different fishing intensity periods in two Mediterranean demersal fishing grounds. Sci. Mar. 71(4): 765-773.

Shannon C.E., Weaver V. 1949. A mathematical theory of communication. Univ. of Illinois Press, Urbana.

Smith C.J., Papadopoulou K.N., Diliberto S. 2000. Impact of otter trawling on an eastern Mediterranean commercial trawl fishing ground. ICES J. Mar. Sci. 57: 1340-1351. http://dx.doi.org/10.1006/jmsc.2000.0927

Stefanescu C., Lloris D., Rucabado J. 1993. Deep-sea fish assemblages in the Catalan Sea (western Mediterranean) below a depth of 1000 m. Deep-Sea Res. Pt. I 40: 695-707. http://dx.doi.org/10.1016/0967-0637(93)90066-C

Stergiou K.I, Pollard D.A. 1994. A spatial analysis of the commercial fisheries catches from the Greek Aegean Sea. Fish. Res. 20: 109-135. http://dx.doi.org/10.1016/0165-7836(94)90078-7

Stergiou K.I., Politou C.-Y., Christou E.D. et al. 1997. Selectivity experiments in the NE Mediterranean: the effect of trawl codend mesh size on species diversity and discards ICES J. Mar. Sci. 54: 774-786. http://dx.doi.org/10.1006/jmsc.1997.0231

Stergiou K.I., Economou A., Papaconstantinou C. et al. 1998. Estimates of discards in the Hellenic commercial trawl fishery. Rapp. Comm. Mer. Médit. 35: 490-491.

Tırasın E.M., Unloglu A., 2012. Demersal and Deep Water Fisheries Resources in the Turkish Seas. In A. Tokaç, A.C. Gu.cu. and B. O¨ztu¨rk (eds) The State of The Turkish Fisheries. Published by Turkish Marine Research Foundation, Istanbul, Turkey. pp. 28-91.

Tokaç A. Lök A., Tosuno?lu Z. et al. 1998. Cod-end selectivities of a modified bottom trawl for three fish species in the Aegean Sea. Fish. Res. 39: 17-31. http://dx.doi.org/10.1016/S0165-7836(98)00172-6

Tokaç A., Özbilgin H., Tosuno?lu Z. 2004. Comparison of the selectivity of PA and PE codends. Fish. Res. 67: 317-327. http://dx.doi.org/10.1016/j.fishres.2003.10.001

Tosuno?lu Z., Do?anyılmaz Y., Özbilgin Y.D. 2003a. Body shape and trawl codend selectivity for nine commercial fish species. J. Mar. Biol. Assoc. U.K. 83: 1309-1313.

Tosuno?lu Z., Özbilgin H., Tokaç A. 2003b. Effects of the protective bags on the cod-end selectivity in Turkish bottom trawl fishery. Arch. Fish. Mar. Res. 50: 239-252.

Tsagarakis K, Coll M., Giannoulaki M. et al. 2010. Food-web traits of the North Aegean Sea ecosystem (Eastern Mediterranean) and comparison with other Mediterranean ecosystems. Est. Coast. Shelf Sci. 88: 233-248. http://dx.doi.org/10.1016/j.ecss.2010.04.007

Tsagarakis K., Palialexis A., Vassilopoulou V. 2013. Mediterranean fishery discards: review of the existing knowledge. ICES J. Mar. Sci.

Tsimenides N., Tserpes G., Machias A. et al. 1991. Distribution of fishes on the Cretan shelf. J. Fish. Biol. 39: 661-672. http://dx.doi.org/10.1111/j.1095-8649.1991.tb04396.x

Tudela S. 2004. Ecosystem effects of fishing in the Mediterranean: An analysis of the major threats of fishing gear and practices to biodiversity and marine habitats. Studies and Reviews No: 74 GFCM, FAO. Rome. 44 pp. PMCid:PMC1224224

TUIK (Turkish Statistical Institute) 2009. Fishery Yearbook of Statistics 2009. Turkish Statistical Association. Prime Ministry, Ankara.

Vassilopoulou V., Papaconstantinou C. 1998. Discarding at sea by commercial trawlers in Greek waters. Rapp. Comm. int. Mer. Médit. 35: 502-503.




Copyright (c) 2014 Consejo Superior de Investigaciones Científicas (CSIC)

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.


Contact us scimar@icm.csic.es

Technical support soporte.tecnico.revistas@csic.es