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Marine mammal bycatch in Spanish Mediterranean large pelagic longline fisheries, with a focus on Risso’s dolphin (Grampus griseus)

Published online by Cambridge University Press:  17 December 2012

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Abstract

The western Mediterranean is an important fishing area in which the Spanish longline fleet operates. Longline fisheries affect several species of marine mammals, sea turtles, sharks and seabirds, all of which are especially sensitive to fishing mortality. Given international efforts to identify and reduce the bycatch of sensitive species, an onboard observer program was implemented by the Spanish Oceanographic Institute (IEO, Instituto Español de Oceanografía). The aim of the present study was to report data on marine mammal bycatch in the western Mediterranean. The additional aim was to improve knowledge about the possible effects of the Spanish longline fisheries on cetacean populations, particularly Risso’s dolphin, and to suggest improvements to fisheries management. Data on marine mammal bycatch were collected during the period 2000–2009. Differences are reported for catch per unit effort (CPUE, defined as marine mammals per 1000 hooks) for each type of gear (n = 7), as well as their effect on specific marine mammal species. A total of 5 398 297 hooks were monitored, which yielded 56 marine mammals belonging to 4 different species. Our results indicate that Risso’s dolphin is the species most affected by the longline fishery in the western Mediterranean (n = 33). We built a predictive model for Risso’s dolphin bycatch using variables associated with the technical characteristics of the fishery, geographic location and seasonality. We performed a binary logistic regression of the presence/absence of Risso’s dolphin bycatch to test whether the probability of incidentally catching one or more dolphins may be predicted by some of the explanatory variables selected. Our results indicate that Risso’s dolphin was mainly caught using Japanese longline (LLJAP) or an experimental home-based longline (LLHBexp) over the continental shelf. Because LLHBexp is an experimental type of gear that was only used occasionally by the fleet, controlling the use of LLJAP over the continental shelf could strongly reduce the impact of these fisheries on populations of Risso’s dolphin in the western Mediterranean.

Type
Research Article
Copyright
© EDP Sciences, IFREMER, IRD 2012

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References

Báez, J.C., Real, R., Camiñas,, J.A., 2007a, Differential distribution within longline transects of loggerhead and swordfish captured by the Spanish Mediterranean surface longline fishery. J. Mar. Biol. Assoc. UK 87, 801803. CrossRefGoogle Scholar
Báez, J.C., Real, R., García-Soto, C., de la Serna, J.M., Macias, D., Camiñas, J.A., 2007b, Loggerhead turtle by-catch depends on distance to the coast, independent of fishing effort : implications for conservations and fisheries management. Mar. Ecol. Prog. Ser. 338, 249256. CrossRefGoogle Scholar
Báez J.C., Real R., Camiñas J.A., Torreblanca D., Garcia-Soto C., 2009, Analysis of swordfish catches and by-catches in artisanal longline fisheries in the Alboran Sea (western Mediterranean Sea) during the summer season. Mar. Biodiv. Rec. 2, e157, doi : 10.1017/S1755267209990856.
Báez, J.C., Real, R., Bellido, J.J., Macias, D., de la Serna, J.M., Camiñas,, J.A., 2011, Validating an ecological model with fisheries management applications : the relationship between loggerhead bycatch and distance to the coast. J. Mar. Biol. Assoc. UK 91, 13811383. CrossRefGoogle Scholar
Báez, J.C., Real, R., Macias, D., de la Serna, J.M., Bellido, J.J., Camiñas, J.A., 2010, Swordfish Xiphias gladius Linnaeus 1758 and loggerhead Caretta caretta (Linnaeus 1758) captures associated with different combinations of bait in the western Mediterranean surface longline fishery. J. Appl. Ichthyol. 26, 126127. CrossRefGoogle Scholar
Blanco, C.Raduan, M.A., Raga, J.A., 2006, Diet of Risso’s dolphin (Grampus griseus) in the western Mediterranean Sea. Sci. Mar. 70, 407411. Google Scholar
Baird R.W., 2002, Risso’s dolphin. In : Perrin W.F., Würsig B., Thewissen J.G.M. (Eds.) Encyclopedia of marine mammals. San Diego, Academic Press, pp. 1037–1039.
Bearzi, G., Reeves, R.R., Remonato, E., Pierantonio, N., Airoldi, S., 2011, Risso’s dolphin Grampus griseus in the Mediterranean Sea. Mammal Biol. 76, 385400. CrossRefGoogle Scholar
Benjamini, Y., Hochberg, Y., 1995, Controlling the false discovery rate : a practical and powerful approach to multiple testing. J. R. Stat. Soc. B 57, 289300. Google Scholar
Bierzi G., 2002, Interactions between cetacean and fisheries in the Mediterranean Sea. In : Notarbartolo di Sciara (Ed.), Cetaceans of the Mediterranean and Black Seas : state of knowledge and conservation strategies. A report to the ACCOBAMS Secretariat, Monaco 9, 20 p.
Camiñas, J.A., Báez, J.C., Valeiras, J., Real, R., 2006, Differential loggerhead by-catch and direct mortality in surface longline according to boat strata and gear type. Sci. Mar. 70, 661665. CrossRefGoogle Scholar
Camiñas, J.A., Valeiras, J., 2001, Marine turtles, mammals and sea birds captured incidentally by the Spanish surface longline fisheries in the Mediterranean Sea. Rapp. Comm. Int. Mer Médit. 36, 248. Google Scholar
Clarke, M.R., 1996, Cephalopods as prey. III. Cetaceans. Phil. Trans. R. Soc. Lond. Ser. B 351, 10531065. CrossRefGoogle Scholar
Crespo, E.A., Pedraza, S.N., Dans, S.L., Koen Alonso, M., Reyes, L.M., García, N.A., Coscarella, M., Schiavini, A.C.M., 1997, Direct and indirect effects of the high seas fisheries on the marine mammal population in the northern and central Patagonian coast. J. Northwest Atl. Fish. Soc. 22, 189207. CrossRefGoogle Scholar
Di Natale, A., 1990, Interaction between marine mammals and Scombridae fishery activities : The Mediterranean case. FAO Fish. Rep. 449, 167174. Google Scholar
Duguy, R., Casinos, A., Di Natale, A., Filella, S., Ktari-Chakroun, F., Lloze, R., Marchessaux, D., 1983a, Répartition et fréquence des mammifères marins en Méditerranée. Rapp. Comm. Int. Mer Médit. 28, 223230. Google Scholar
Duguy, R., Besson, J., Cassinos, A., Di Natale, A., Filella, S., Raduan, A., Raga, J., Viale, D., 1983b, L’impact des activités humaines sur les cétacés de la Méditerranée occidentale. Rapp. Comm. Int. Mer Médit. 28, 219222. Google Scholar
García, L.V., 2003, Controlling the false discovery rate in ecological research. Trends Ecol. Evol. 18, 553554. CrossRefGoogle Scholar
García-Barcelona, S., Ortiz de Urbina, J.M., de la Serna, J.M., Alot, E., Macias, D., 2010a, Seabird by-catch in Spanish Mediterranean large pelagic longline fisheries, 1998–2008. Aquat. Living Resour. 23, 363371. Google Scholar
García-Barcelona, S., Macías, D., Ortiz De Urbina, J.M., Estrada, A., Real, R., Báez, J.C., 2010b, Modelling abundance and distribution of seabird by-catch in the Spanish Mediterranean longline fishery. Ardeola 57, 6578. Google Scholar
Gerrodette, T., Forcada, J., 2005, Non-recovery of two spotted and spinner dolphin populations in the eastern tropical Pacific Ocean. Mar. Ecol. Prog. Ser. 291, 121. CrossRefGoogle Scholar
Garrison, L.P., 2007, Interactions between marine mammals and pelagic longline fishing gear in the U.S. Atlantic Ocean between 1992 and 2004. Fish. Bull. 105, 408417. Google Scholar
Gomez de Segura, A., Crespo, E.A., Pedraza, S.N., Hammond, P.S., Raga, J.A., 2006, Abundance of small cetaceans in waters of the central Spanish Mediterranean. Mar. Biol. 150, 149160. CrossRefGoogle Scholar
Hosmer D.W., Lemeshow S., 2000, Applied logistic regression, 2nd edn. New York, John Wiley and Sons, Inc.
Jefferson T.A., Leatherwood S., Webber M.A., 1993, FAO Species identification guide. Marine mammals of the world. UNEP/FAO. Rome.
Macias D., Báez J.C., García S., Ortíz De Urbina J.M., 2012, Dolphinfish bycatch in Spanish Mediterranean large pelagic longline fisheries, 2000–2010. Scient. World J. doi :10.1100/2012/104389.
Macías, D., Gómez-Vives, M.J., de la Serna, J.M., 2004, Desembarcos de especies asociadas a la pesquería de palangre de superficie dirigido al pez espada (Xiphias gladius) en el Mediterráneo durante 2001 y 2002. ICCAT Col. Vol. Sci. Pap. 56, 981986. Google Scholar
Mangion, P., Gannier, A., 2002, Improving the comparative distribution picture for Risso’s dolphin and long-finned pilot whale in the Mediterranean Sea. Eur. Res. Cetaceans 16, 68. Google Scholar
Minami, M., Lennert-Cody, C.E., Gao, W., Román-Veredesoto, M., 2007, Modeling shark bycatch : The zero-inflated negative binomial regression model with smoothing. Fish. Res. 84, 210221. CrossRefGoogle Scholar
Mussi, B., Gabriel, R., Miragliuolo, A., Battaglia, M., 1998, Cetacean sightings and interactions with fisheries in the archipielago Pontino Campano, southern Tyrrhenian Sea, 1991–1995. Eur. Res. Cetaceans 12, 6365. Google Scholar
Oeztuerk, B., Salman, A., Oeztuerk, A.A., Tonay, A., 2007, Cephalopod remains in the diet of striped dolphins (Stenella coeruleoalba) and Risso’s dolphins (Grampus griseus) in the eastern Mediterranean Sea. Vie Milieu 57, 5359. Google Scholar
Real, R., Barbosa, A.M., Vargas, J.M., 2006, Obtaining environmental favourability functions from logistic regression. Environ. Ecol. Stat. 13, 237245. CrossRefGoogle Scholar
Sánchez, P., 1986, Distribución batimétrica y abundancia de algunos cefalópodos del mar Catalán. Invest. Pesq. 50, 237245. Google Scholar
Sokal R.R., Rohlf F.J., 1995, Biometry. 3rd edn., New York, W.H. Freeman and Co.
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 habits. General Fisheries Commission for the Mediterranean (FAO), Stud. Rev. 74, FAO, Rome.
University of Barcelona, 1995, A survey of interactions between marine mammals and fisheries in the south western waters of the EEC (SUROESTE). Final Report to the General Directorate for Fisheries, EC DGXIV. Project PEM/92/3507.
Valeiras, J., Camiñas, J.A., 2003, The incidental capture of seabirds by Spanish drifting longline fisheries in the western Mediterranean Sea. Sci. Mar. 67, 6568. CrossRefGoogle Scholar
Ward, P., Myers, R.A., Blanchard, W., 2004, Fish lost at sea : the effect of soak time on pelagic longline catches. Fish. Bull. 102, 179195. Google Scholar
Würtz, M., Poggi, R., Clarke, M. R., 1992, Cephalopods from the stomach of a Risso’s dolphin (Grampus griseus) from the Mediterranean. J. Mar. Biol. Assoc. UK 72, 861867. CrossRefGoogle Scholar