Browsing by Author "Fernandes, Ana Cláudia"
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- Discards from the Portuguese bottom otter trawl operating in ICES Division 27.9.a (2004-2015)Publication . Fernandes, Ana Cláudia; Prista, Nuno; Azevedo, Manuela; Instituto Português do Mar e da Atmosfera, I.P.This document compiles the information available on discards from Portuguese vessels operating with bottom otter trawl (OTB) in the Portuguese ICES Division 27.9.a, estimated by IPMA for the period 2004- 2015. These discards include species from the stocks assessed in ICES assessment Working Groups and species commercially important at national level. The samples were collected by the onboard sampling programme of the National Programme for Biological Sampling (PNAB/EU DCF), integrated in the National Data Collection Framework . The onboard sampling programme, estimation algorithms and data quality assurance procedures are described and results for two fisheries provided: the crustacean bottom otter trawl fishery (OTB_CRU) and the demersal bottom otter trawl fish fishery (OTB_DEF). Estimates of discard volume and length composition are provided for the ‘year, fishery, species’ combinations where they are frequently observed ( 30% of sampled hauls). Results show that although there’s a large number of species discarded, the number of species frequently discarded is very low (7% in OTB_CRU and 4% in OTB_DEF). Mean number of discards per haul is calculated for all species that occurred in discards and analysis of length compositions are displayed for selected species. Analyses of the combined results indicates that a large part of the species selected for this work are either absent in discards or very rarely discarded. Indications are given on possible discarding reasons and on the discard estimation methodology to be developed for less frequent species and for other Portuguese fleet components.
- Report of the Workshop on Sampling Design and Optimization of fisheries data - WKSDOPublication . Azevedo, Manuela; Silva, Cristina; Vølstad, Jon Helge; Prista, Nuno; Alpoim, Ricardo; Moura, Teresa; Figueiredo, Ivone; Dias, Marina; Fernandes, Ana Cláudia; Lino, Pedro G.; Felício, Mónica; Chaves, Corina; Soares, Eduardo; Dores, Sandra; Gonçalves, Patrícia; Costa, Ana Maria; Nunes, Cristina; Instituto Português do Mar e da Atmosfera, I.P.O “Workshop on Sampling Design and Optimization (WKSDO)”, presidido pelas investigadoras Cristina Silva e Manuela Azevedo (IPMA) e o investigador Norueguês Jon H. Vølstad (IMR), decorreu no IPMAAlgés, de 17 a 20 de Novembro de 2014, para analisar o actual Programa Nacional de Amostragem Biológica (PNAB/Data Collection Framework) com o objectivo de optimizar o programa de amostragem em lota para estimação da composição por comprimento da captura/desembarque das espécies capturadas pela frota nacional, de amostragem das capturas a bordo e da amostragem biológica para estudos de crescimento e reprodução. O Workshop, organizado no âmbito do projecto de investigação nacional GesPe (Planos de Gestão Pesqueira, PROMAR) e do PNAB/DCF, foi planeado e calendarizado tendo em conta o início do processo de revisão do programa Europeu de recolha de dados da pesca de suporte à avaliação e gestão dos recursos pesqueiros (DFC). Foram analisados e discutidos vários métodos e abordagens que resultaram num conjunto de instruções e recomendações para trabalho futuro, relevantes para assegurar uma elevada qualidade e optimização do futuro programa de amostragem.