Spanish discards for southern hake stock

• Main Authors: Santos-Blanco, J. (Juan), Velasco, F. (Francisco), Punzón, A. (Antonio), Quinzán, M. (Marta), Pérez-Contreras, M.N. (María Nélida)
• Format: Report
• Language: English
• Published: Centro Oceanográfico de Vigo 2008
• Subjects: Hake; North Atlantic; Northeast Atlantic
• Online Access: http://hdl.handle.net/10508/8991

A Spanish Discard Sampling Programme is being carried out in Divisions VIIIc and IXa North since 1993. The series provides information on discarded catch in weight and number and length distributions for Southem hake. Spanish sampling was used for years 1994, 1997, 1999- 2000 and 2003-2007. The number of trips sampled by the Spanish program was distributed by three trawl fleets: Baca otter trawl, Pair trawl and HVO trawl. Effort (trips number), hake landings and target species landings were the three variables tested to raise the Spanish discard, and the total effort by fleet gave the best results and hence it was used to estimate total discards. Hake discards for the Spanish fleet were estimated to vary between 240t (C.V. = 22.3) and 2 650t (C.V. = 24.3%). Estimated percentages of discarded hake in relation to total catch ranges between 9% and 31% in weight and 50% and X9% in number. As the Spanish estimated discard sampling is not based on yearly information, the relationships with Spanish survey (SP-GFS) abundance indices of age O was used to estimate discard abundanccs in those years were discard sampling was not performed. First ages (0, 1) were assumed to be discarded, and used in the estimates.