Summary: | The interaction between seabirds and fishing operations has been i de n tified as the main cause for diminishing albatros and petrel populations ( Procellariiformes ) . In Chile, the industrial longline fishery targeting swordfish ( Xiphias gladius ) is currently monitoring seabird bycatch by trained onboard scientific observers. Fr om 2005 to 2010 a total of 232 seabirds were reported as bycatch in this fishery belonging to 14 species . In terms of frequency, the most important were: Black - browed Albatross (n=123), Wandering Albatross (n=30), Cape Hen (n=23), Grey - headed Albatross (n=15), Buller's Albatross (n= 12). The seabird by catch rate, measured as number of seabird caught per 1000 soaked hook s , indicated a maximum by catch rate of 0.07 in 2007 whereas in 2010 it decreased to 0.01. The swordfish’s fishery operate s throughout the year, howeve r, t he seabird byc atch is observed only between May and October which maximum is reached in September. A clear spatial distribution of seabird bycatch is also observed between Valparaiso (33 °S) and the North of Caldera (27°S). A number of m itigation measures have been impo sed by Chilean authorities , Plan de Acción Nacional - Aves Marinas (PAN - AM), where the most important are the use of Tori lines, fishing operation restricted only to night setting (one hour after the sunset and one hour before the sunrise) and a minimum lin e weight of 60 g. From a total of 814 fishing hauls observed in 2010 only the 5.14% o used tori line and the 28% of them were setting overnight , whereas the minimum weight line is always reached. Mitigation measures are compulsory although only a small pro portion of fishing hauls acomplished their requirements. Thus, a monitoring program must be enforced and fishing crew should be informed about the impor tance of seabird conservation La interacción entre las aves marinas y las operaciones de pesca se ha identificado como la causa principal de la disminución de albatros y petreles (poblaciones Procellariiformes). En Chile,en la ...
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