Interactions between small cetaceans and the purse-seine fishery in western Portuguese waters

Laura Wise; Alexandra Silva; Marisa Ferreira; Mónica A. Silva; Marina Sequeira

doi:10.3989/scimar.2007.71n2405

Authors

Laura Wise INIAP-IPIMAR, Lisboa
Alexandra Silva INIAP-IPIMAR, Lisboa
Marisa Ferreira Instituto da Conservação da Natureza, Lisboa
Mónica A. Silva Departamento de Oceanografia e Pescas, Horta
Marina Sequeira Instituto da Conservação da Natureza, Lisboa

DOI:

https://doi.org/10.3989/scimar.2007.71n2405

Keywords:

purse-seine, fishing activity, marine mammals, interaction

Abstract

Marine mammal interactions with Portuguese purse-seine fisheries operating in four different ports (Figueira da Foz, Sesimbra, Setúbal, Sines) were studied (July-October 2003). Observers accompanied commercial fishing vessels and monitored 48 fishing trips. An interview survey of skippers was also carried out (n = 36). Three species of marine mammals were observed in 31 sightings during the commercials trips but only the species Delphinus delphis and the category Delphinidae were observed to interact with fishing activities. Small cetaceans were observed to sink, gather or disperse school fishes and damage gear. Mean CPUE and fishing effort values did not change significantly in the presence of dolphins (H = 0.06 and H = 0, both p>0.05). Results from Figueira da Foz indicate that cetaceans are attracted to fishing grounds with a high abundance of their prey-species. Fishermen reported three by-catch events off Figueira da Foz. Compared with other fisheries, purse-seine fishing does not seem to be among the most damaging to marine mammals.

Downloads

Download data is not yet available.

References

Aguilar, A. – 1991. Calving and early mortality in the western Mediterranean striped dolphin, Stenella coeruleoalba. Can. J. Zool., 69: 1408-1412.

Aguilar, A. – 1997. Inventario de los cetáceos de las aguas atlánticas peninsulares: aplicación de la directiva 92/43/CEE. Memoria Final. Departamento de Biologia Animal (Vert.), Facultad de Biologia, Univ. Barcelona.

Crespo, E.A., S.N. Pedraza, S.L. Dans, M.K. Alonso, L.M. Reyes, N.A. Garcia and M. Coscarella. – 1997. Direct and indirect effects of the high seas fisheries on the marine mammal populations in the northern and central Patagonian coast. J. Northw. Atl. Fish. Sci., 22: 189-207.

dos Santos, M.E. – 1998. Golfinhos-Roazes do Sado – Estudos de Som e Comportamento. ISPA, Lisboa.

Ferreira, M. – 2000. Monotorização de uma população de bôtos (Phocoena phocoena L.) na região do Cabo Mondego. Degree thesis, Instituto da Conservação da Natureza.

Fréon, P. and O.A. Misund. – 1999. Dynamics of pelagic fish distribution and behaviour: effects on fisheries and stock assessment. Fishing News Books, Oxford.

Harwood, J. – 1983. Interactions between marine mammals and fisheries. Adv. Appl. Biol., 28: 189-214.

Hilborn, R. and C.J. Walters. – 1992. Quantitative fisheries stock assessment: choice, dynamics and uncertainty. Chapman & Hall, New York.

ICES. – 2006. Report to the Working Group on the assessment of Mackerel, Horse Mackerel, Sardine, and Anchovy. International Council for the Exploration of the Sea (CM Papers and Reports). ICES CM 2006/ACFM: 8. 631 pp.

Kobayashi, D.R. and K.E. Kawamoto. – 1995. Evaluation of shark, dolphin, and monk seal interactions with northwestern Hawaiian Island bottom fishing activity: a comparison of two time periods and an estimate of economic impacts. Fish. Res., 23: 11-22. doi:10.1016/0165-7836(94)00338-W

López, A., G.J. Pierce, M.B. Santos, J. Gracia and A. Guerra. – 2003. Fishery by-catches of marine mammals in Galician waters: results from on-board observations and an interview survey of fishermen. Biol. Conserv., 111: 25-40. doi:10.1016/S0006-3207(02)00244-6

Marques, V., A. Morais and G. Pestana. – 2003. Distribuição, Abundância e Evolução do Manancial de Sardinha Presente na Plataforma Continental Portuguesa entre 1995 e 2002. Relat. Cient. Téc. IPIMAR, Série digital (http://ipimar-iniap.ipimar.pt) nº 10, 29 pp.

Meyer, M.A., P.G.H. Kotze and G.W. Brill. – 1992. Consumption of the catch and interference with linefishing by South (Cape) Fur Seals Arcotocephalus pusillus pusillus. S. Afr. J. Mar. Sci., 12: 835-842.

Misund, O.A. – 1993. Avoidance behaviour of herring (Clupea harengus) and mackerel (Scomber scombrus) in purse seine capture situations. Fish. Res., 16: 179-194. doi:10.1016/0165-7836(93)90051-8

Misund, O.A. – 1994. Swimming behaviour of fish schools in connection with capture by purse seine and pelagic trawl. In: A. Ferno and S. Olsen (eds.), Marine fish behaviour in capture and abundance estimation, pp. 84-106. Fishing News Books.

Morizur, Y., S.D. Berrow, N.J.C. Tregenza, A.S. Couperus and S. Pouvreau. – 1999. Incidental catches of marine-mammals in pelagic trawl fisheries of the northeast Atlantic. Fish. Res., 41: 297-307. doi:10.1016/S0165-7836(99)00013-2

Nitta, E.T. and J.R. Henderson. – 1993. A review of interactions between Hawaii’s fisheries and protected species. Mar. Fish. Rev., 55(2): 83-92.

Northridge, S.P. – 1991. Estudo mundial de las interacciones entre los mamíferos marinos y la pesca. FAO Inf. Pesca., 251: 234 pp.

Pauly, A., A.W. Trites, E. Capuli and V. Christensen. – 1998. Diet composition and trophic levels of marine mammals. ICES J. Mar. Sci., 55: 467-481. doi:10.1006/jmsc.1997.0280

Parente, J. – 2000. Frota costeira de cerco. Análise das dimensões e de alguns parâmetros de exploração, numa perspectiva global e regional. Relat. Cient. Téc. Inst. Invest. Pescas Mar nº 62, 48 pp.

Pierce, G.J., J. Dyson, E. Kelly, J.D. Eggleton, P. Whomersley, I.A.G. Young, M.B. Santos, J. Wang and N. Spencer. – 2002. Results of a short study on by-catches and discards in pelagic fisheries in Scotland (UK). Aquat. Living Resour., 15: 327-334. doi:10.1016/S0990-7440(02)01191-9

Read, A.J. – 1996. Incidental catches of small cetaceans. In: M. P. Simmonds and J. D. Hutchinson (eds.), The conservation of whales and dolphins, pp. 109-128. John Wiley & Sons Ltd.

Santos, M.B., G.J. Pierce, A. López, J.A. Martínez, M.T. Fernández, E. Ieno, E. Mente, C. Porteiro, P. Carrera and M. Meixide. – 2004. Variability in the diet of common dolphins (Delphinus delphis) in Galician waters 1991-2003 and relationship with prey abundance. ICES CM 2004 Q:09.

Santos, M.B., R. Fernández, A. Lopez, J.A Martínez and G.J. Pierce. – 2007. Variability in the diet of bottlenose dolphin, Tursiops truncatus, in Galician waters, north-western Spain, 1990-2005. J. Mar. Biol. Ass. U.K., 87: 231-242. doi:10.1017/S0025315407055233

Scientific, Technical and Economics Committee for Fisheries. – 2002. 14th Report of the Scientific, Technical and Economics Committee for Fisheries.

Sequeira, M. and C. Ferreira. – 1994. Coastal Fisheries and Cetacean Mortality in Portugal. Rep. Int. Whal. Commn., 15: 165-174.

Sequeira, M., A. Inácio and M.A. Silva. – 1997. Cetacean strandings in Portugal: 1993-1995. Eur. Res. Cetaceans., 10: 136-140.

Silva, M. – 1999. Diet of common dolphins, Delphinus delphis, off the Portuguese continental coast. J. Mar. Biol. Ass. U.K., 79: 531-540. doi:10.1017/S0025315498000654

Silva, M.A. and M. Sequeira. – 2003. Patterns in the mortality of common dolphins (Delphinus delphis) on the Portuguese coast, using stranding records, 1975-1998. Aquatic Mammals, 29 (1): 88-98. doi:10.1578/016754203101023924

Silva, M.A., R. Feio, R. Prieto, J.M. Gonçalves and R.S. Santos. – 2002. Interactions between cetaceans and the tuna fishery in the Azores. Mar. Mamm. Sci., 18(4): 893-901. doi:10.1111/j.1748-7692.2002.tb01080.x

Stratoudakis, Y. and A. Marçalo. – 2002. Sardine Slipping during purse-seining off northern Portugal. ICES J. Mar. Sci., 59: 1256-1262. doi:10.1006/jmsc.2002.1314

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. General Fisheries Commission for the Mediterranean. No. 74. FAO, Rome.

Waring, G.T., P. Gerrior, P.M. Payne, B.L. Parry and J.R. Nicolas. – 1990. Incidental take of marine mammals in foreign fishery activities off the Northeast United States, 1977-88. Fish. Bull., 88 (2): 347-360.

Wickens, P.A., D.W. Japp, P.A. Shelton, F. Kriel, P.C. Goosen, B. Rose, C.J. Augustyn, C.A.R. Bross, A.J. Penney and R.G. Krohn. – 1992. Seals and fisheries in South Africa – competition and conflict. S. Afr. J. Mar. Sci., 12: 773-789.

Zar, J. – 1999. Biostatistical Analysis. Prentice Hall. 4 th Ed., New York.