Fishing activity and impacts along the main nesting area of loggerhead sea turtle <i>Caretta caretta</i> in Italy: overwhelming discrepancy with the official data

Giulia Cambiè; Juan Antonio Camiñas; Ramón Franquesa; Toni Mingozzi

doi:10.3989/scimar.2010.74n2275

Authors

Giulia Cambiè Department of Animal Biology, Vegetal Biology and Ecology, University of A Coruña
Juan Antonio Camiñas FAO-CopeMed II Project. Spanish Government Delegation in Málaga
Ramón Franquesa Cabinet of Marine Economics, University of Barcelona
Toni Mingozzi Department of Ecology, University of Calabria

DOI:

https://doi.org/10.3989/scimar.2010.74n2275

Keywords:

Caretta caretta, fishing impact, by-catch, surface longline, drift nets, illegal fishing, artisanal fishing, IUU

Abstract

The southern coast of Ionian Calabria was recently recognized as the main nesting area of the loggerhead sea turtle Caretta caretta in Italy. The aim of this study was to characterize the fishing fleet in this area in terms of number of boats, economic situation, social aspects and impact on sea turtle specimens and target species. A multidisciplinary approach was essential to understand how the conservation problems of C. caretta are linked to various characteristics of the fishing fleet. Our data showed a vast discrepancy between the official census and the actual number of boats fishing in the area: 87% of the observed artisanal vessels lacked a required registration number, and thus were fishing illegally. This has caused serious social problems that worsened over the summer of 2007, when the presence of non-local registered vessels, using drift nets, generated a spatial conflict with the local artisanal fishermen. We identified 11 fishing gears used in the area and four of them were studied with on board observations: illegal drift nets, trammel nets, bottom longlines and longlines targeting swordfish. The total number of turtles caught during the summer in the area by longliners targeting swordfish was calculated to be 500 (±180 SE). In addition the presence of drift netters had a negative impact from an ecological and social point of view.

Downloads

Download data is not yet available.

References

ATRT. – 2008. The 2008 BlueFin Tuna dossier: Italy. Assessment of compliance of Italian fleets and ranches with management rules during the 2008 BlueFin Tuna fishing season. WWF Mediterranean and WWF Italy.

Bolten, A.B. – 1999. Techniques for measuring sea turtles. In: K.L. Eckert, K.A. Bjorndal, F.A. Abreu-Grobois and M. Donnelly (eds.), Research and Management Techniques for the Conservation of Sea Turtles, pp. 100-114. IUCN/SSC Marine Turtle Specialist Group Publication No. 4.

Camiñas, J.A., J.C. Báez, X. Valeiras and R. Real. – 2006. Differential loggerhead by-catch and direct mortality due to surface longlines according to boat strata and gear type. Sci. Mar., 70: 661-665.

Camiñas, J.A., J. Baro, J.A. Reina. – 1986. Pesquerías artesanales del Mar de Alboran. Proyecto cooperativo IEO/CEE XIV-B-1-86/XII/3857.

Casale, P. – 2008. Incidental catch of marine turtles in the Mediterranean Sea: captures, mortality, priorities. WWF Italy, Rome.

Casale, P., L. Cattarino, D. Freggi, M. Rocco and R. Argano. – 2007. Incidental catch of marine turtles by Italian trawlers and longliners in the central Mediterranean. Aquatic Conserv: Mar. Freshw. Ecosyst., 17: 686-701. doi:10.1002/aqc.841

Casale, P., D. Freggi and M. Rocco. – 2008. Mortality induced by drifting longline hooks and branchlines in loggerhead sea turtles, estimated through observation in captivity. Aquatic Conserv: Mar. Freshw. Ecosyst., 18: 945-954. doi:10.1002/aqc.894

Cornax, M.J., X. Pastor and R. Aguilar. – 2006. Reti derivanti italiane2006: il rapporto di OCEANA. OCEANA.

Deflorio, M., A. Aprea, A. Corriero, N. Santamaria and G. De Metrio.– 2005. Incidental captures of sea turtles by swordfish and albacore longlines in the Ionian Sea. Fish. Sci., 71: 1010-1018. doi:10.1111/j.1444-2906.2005.01058.x

Delaugerre, M. – 1987. Statut des tortues marines de la Corse (et de la Mediterranee). Vie Milieu, 37(3/4): 243-264.

De Metrio, G. and P. Megalofonou. – 1988. Mortality of marine turtles (Caretta caretta L. and Dermochelys coriacea L.) consequentto accidental capture in the Gulf of Taranto. Rapp. Comm. Int. Mer Mèdit. 31 (2): 285.

FAO. – 1995. Code of Conduct for Responsible Fisheries. Rome, FAO. 1995. 1-41.

FAO. – 2001. International Plan of Action to prevent, deter and eliminate illegal, unreported and unregulated fishing. In: FAO Fisheries and Aquaculture Department [online]. Rome, FAO.

FAO. – 2005-2009. Fisheries Issues. Selectivity of gear. Text by John Willy Valdemarsen. In: FAO Fisheries and Aquaculture Department [online]. Rome.

Franquesa, R., A. El Abed, A. Aboukhader, S. Ben Salem, D. Ferhane, J. Guillén, J.A. Alarcón, M.I. Mohammed, M. Hachemane and M. Zergani. – 2005. La estimación de indicadores económicos en las pesquerías mediterráneas. Franquesa, R. (ed.) Report FAO-COPEMED Project.

GFCM. – 2005. Report of the twenty-ninth session. Rome, 21-25 February 2005.

GFCM. – Report. No. 29. In: FAO Fisheries and Aquaculture Department [online]. Rome, FAO.

Gordon, H. – 1954. The economic theory of a common property: The fishery. J. Political Econ., 62(2): 124-142. doi:10.1086/257497

ICCAT. – 2008. Report of the 2008 Atlantic bluefin tuna stock assessment session, Madrid, Spain, June 23-July 4, 2008. ICCAT, Madrid.

Irepa. – 2003. Osservatorio economico sulle strutture produttive della pesca marittima in Italia 2001-2002. XI Rapporto, Collana Irepa Ricerche, pp 151-166. Franco Angeli (eds.).

Irepa. – 2007. Osservatorio economico sulle strutture produttive della pesca marittima in Italia 2006. XV Rapporto, Collana Irepa Ricerche, pp. 97-104. Franco Angeli (eds.).

Lewison, R.L. and L.B. Crowder. – 2007. Putting longline bycatch of sea turtles into perspective. Conserv. Biol., 21(1): 79-86. doi:10.1111/j.1523-1739.2006.00592.x PMid:17298513

Lewison, R.L., S.A. Freeman and L.B. Crowder. – 2004. Quantifying the effects of fisheries on threatened species: the impact of pelagic longlines on loggerhead and leatherback sea turtles. Ecol. Lett., 7: 221-231. doi:10.1111/j.1461-0248.2004.00573.x

Lutcavage, M.E., P. Plotkin, B. Witherington and P.L. Lutz. – 1997. Human impacts on sea turtle survival. In: P.L. Lutz and J.A. Musick (eds.), The biology of sea turtle, pp. 387-409. CRC Press, Boca Raton.

Margaritoulis, D., R. Argano, I. Baran, F. Bentivegna, M.N. Bradai, J.A. Camiñas, P. Casale, G. De Metrio, A. Demetropulos, G. Gerosa, J.G. Brendan, D.A. Haddoud, J. Houghton, L. Laurent and B. Lazar. – 2003. Loggerhead turtles in the Mediterranean Sea: present knowledge and conservation perspectives. In: A.B. Bolten and B.E. Witherington (eds.), Loggerhead sea turtles, pp. 175-198. Smithsonian Books, Washington, DC.

Mingozzi, T., G. Masciari, G. Paolillo, B. Pisani, M. Russo and A. Massolo. – 2007. Discovery of a regular nesting area of loggerhead turtle Caretta caretta in Southern Italy: a new perspective for national conservation. Biodivers. Conserv., 16: 3519-3541. doi:10.1007/s10531-006-9098-6

Önsoy, B. and A. Salaman. – 2005. Reproductive Biology of the Common Cuttlefish Sepia officinalis L. (Sepiida: Cephalopoda) in the Aegean Sea. Turk. J. Vet. Anim. Sci., 29: 613-619.

Otero, J., F. Rocha, A.F. Gonzalez, J. Gracia and A. Guerra. – 2005. Modelling artisanal coastal fisheries of Galicia (NW Spain) based on data obtained from fishers: the case of Octopus vulgaris. Sci. Mar., 69(4): 577-585.

Schaefer, M. – 1954. Some aspects of the dynamics of populations important to the management of the commercial marine fisheries. Bull. Inter-Amer. Trop. Tuna Comm., 1(2): 27-56.

Seijo, J., O. Defeo and S. Salas. – 1997. Bioeconomía pesquera. Teoría, modelación y manejo. FAO Doc. Téc. Pesca, 368: 1-176.

UNEP-RAC/SPA. – 2000. Projet de lignes directrices pour l’etablissement des legislations et des reglementations relatives a la conservation et a la gestion des populations des tortues marines et de leurs habitats. UNEP-RAC/SPA, Tunis 2000.

Young, I.A.G., G.J. Pierce, J. Murphy, H.I. Daly and N. Bailey. – 2006. Application of the Gómez-Muñoz model to estimate catch and effort in squid fisheries in Scotland. Fish. Res., 78: 26-38. doi:10.1016/j.fishres.2005.12.006