Environmental and operational variability affecting the mortality of Black-browed Albatrosses associated with long-liners in Argentina
Agustina Gómez Laich A , Marco Favero A B F , Rocío Mariano-Jelicich B , Gabriel Blanco C , Guillermo Cañete D , Alejandro Arias D E , Patricia Silva Rodriguez A and Hugo Brachetta CA Universidad Nacional de Mar del Plata, Facultad Ciencias Exactas y Naturales, Departamento Biología, Funes 3250, Mar del Plata B7602AYJ, Argentina.
B Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Rivadavia 1917, Buenos Aires C1033AAJ, Argentina.
C Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), Programa de Observadores a Bordo, Paseo V. Ocampo N° 1, Mar del Plata B7602HSA, Argentina.
D Fundación Vida Silvestre Argentina, Programa Marino, Córdoba 2920 4°B, Mar del Plata B7602CAD, Argentina.
E Dirección de Fauna Silvestre, Secretaría de Ambiente y Desarrollo Sustentable, Ministerio de Desarrollo Social y Medio Ambiente, San Martín 459, 2° piso, of. 264, Buenos Aires C1004AAI, Argentina.
F Corresponding author. Email: mafavero@mdp.edu.ar
Emu 106(1) 21-28 https://doi.org/10.1071/MU05024
Submitted: 10 May 2005 Accepted: 11 January 2006 Published: 10 March 2006
Abstract
The effects of different environmental and operational factors on the incidental capture of Black-browed Albatross (Thalassarche melanophris) in long-line fishing operations were analysed. This is the most commonly captured seabird by Argentine long-line fishing vessels, and significant decreases in its populations have been mainly attributed to long-line fishing practices. The estimated mean rate ± s.d. of by-catch for the analysed period (1999–2003) was 0.03 ± 0.39 birds per 1000 hooks. Black-browed Albatrosses were mainly caught during day settings. Higher capture rates were observed during autumn and winter. The effect of the length of long-lines on the incidental capture of Black-browed Albatrosses was also analysed, showing that higher capture rates occurred when short long-lines were deployed. Seasonal differences in the distribution of captures were observed, being widely distributed to the north of the shelf-break during autumn–winter (i.e. non-breeding season) and mostly concentrated in southernmost latitudes, closer to the presumed breeding area in the Malvinas (Falkland) Islands during spring–summer. Mortalities during winter were mainly associated with the Patagonian Toothfish (Dissostrichus eleginoides) fishery, while those observed during summer were associated with long-liners targeting Kingklip (Genypterus blacodes) on the Patagonian Shelf.
Acknowledgments
We thank all the people from the National Observers Program working onboard fishing vessels. We express our gratitude to Pablo Ribeiro for providing statistical advice. We thank Barry Baker and John Croxall for their helpful comments on an earlier version of the manuscript. Thanks to Nic Huin for the authorisation to use the updated information about the population status of Black-browed Albatrosses. We also thank Camilo Katchikian who collaborated in the data processing. Revisions by three anonymous referees helped to improve this manuscript. This work was partly supported by the University of Mar del Plata (Grant 15/E118) and Fundación Antorchas (Grant 13900/13).
Brothers, N. (1991). Albatross mortality and associated bait loss in the Japanese long-line fishery in the Southern Ocean. Biological Conservation 55, 255–268.
| Crossref | GoogleScholarGoogle Scholar |
Cherel, Y. , Weimerskirch, H. , and Duhamel, G. (1996). Interactions between longline vessels and seabirds in Kerguelen waters and a method to reduce seabird mortality. Biological Conservation 75, 63–70.
| Crossref | GoogleScholarGoogle Scholar |
Gandini, P. A. , Frere, E. , Pettovello, A. , and Cedrola, P. (1999). Interaction between magellanic penguins and shrimp fisheries in Patagonia, Argentina. Condor 101, 783–789.
Huin, N. (2002). Foraging distribution of the Black-browed Albatross, Thalassarche melanophris, breeding in the Falkland Islands. Aquatic Conservation: Marine & Freshwater Ecosystems 12, 89–99.
| Crossref | GoogleScholarGoogle Scholar |
Moreno, C. A. , Rubilar, P. S. , Marschoff, E. , and Benzaquen, L. (1996). Factors affecting the incidental mortality of seabirds in the Dissostichus eleginoides fishery in the Southwest Atlantic (Subarea 48.3, 1995 season). CCAMLR Science 3, 79–91.
Reid, T. A. , and Sullivan, B. J. (2004). Longliners, black-browed albatross mortality and bait scavenging in Falkland Island waters: what is the relationship? Polar Biology 27, 131–139.
| Crossref | GoogleScholarGoogle Scholar |
Stagi, A. , and Vaz-Ferreira, R. (2000). Seabird mortality in the waters of the Atlantic Ocean off Uruguay. Marine Ornithology 28, 125–152.
Tasker, M. L. , Camphuysen, C. J. , Cooper, J. , Garthe, S. , Montevecchi, W. A. , and Blaber, S. J. M. (2000). The impacts of fishing on marine birds. ICES Journal of Marine Science 57, 531–547.
| Crossref | GoogleScholarGoogle Scholar |
Thompson, K. R. , and Riddy, M. D. (1995). Utilization of discards from ‘finfish’ trawlers around the Falkland Islands by the Black-browed Albatross Diomedea melanophris. Ibis 137, 198–206.
Tuck, G. N. , Polacheck, T. , and Bulman, C. M. (2003). Spatio-temporal trends of longline fishing effort in the Southern Ocean and implications for seabird bycatch. Biological Conservation 114, 1–27.
| Crossref | GoogleScholarGoogle Scholar |
White, R. W. , Gillon, K. W. , and Black, D. A. (2000). The dispersion of albatross species in the waters of the Falkland Islands. Marine Ornithology 28, 125–152.
Weimerskirch, H. , Capdeville, D. , and Duhamel, G. (2000a). Factors affecting the number and mortality of seabirds attending trawlers and long-liners in the Kerguelen area. Polar Biology 23, 236–249.
| Crossref | GoogleScholarGoogle Scholar |
Weimerskirch, H. , Guionnet, T. , Martin, J. , Shaffer, S. A. , and Costa, D. P. (2000b). Fast and fuel efficient? Optimal use of wind by flying albatrosses. Proceedings of the Royal Society of London 267, 1869–1874.
| Crossref | GoogleScholarGoogle Scholar |