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- Trade of live bait in Portugal and risks of introduction of non-indigenous species associated to importationPublication . Sa, Erica; Fidalgo e Costa, Pedro; Cancela Da Fonseca, Luís; Alves, Ana Sofia; Castro, Nuno; Cabral, Sara dos Santos; Chainho, Paula; Canning-Clode, Joao; Melo, Pedro; Pombo, Ana Margarida; Costa, Jose LinoDifferent invertebrate groups are often exploited on sediment shores and mudflats, including polychaetes, sipunculids, bivalves and crustaceans. The commercial importance of polychaetes and sipunculids, that has increased in the early 2000's because of its use as a food source for the aquaculture sector and a growing demand of worms for use as sea angling bait, seems to be declining nowadays. In Portugal bait harvesting from natural populations became insufficient to meet market demands and as a result, polychaetes and sipunculids have been imported in recent years. Due to this it was important to know the ways of the live bait import to Portugal, and to assess the risk of introduction of non-indigenous species associated to that live bait trade. The origin and quantities of imported live bait were determined by examining the landing's records at Lisbon airport, from two periods: 2002-2003 and 2012-2015. Live worms imported to Portugal arrived almost exclusively from China, USA and Vietnam. Monthly import data and bait registers at fish auction landings were significantly correlated, showing that bait captures and imports are directly related to higher bait demand. In addition, the risk of live bait's importation as an introduction vector for non-indigenous species was evaluated by examining the bait boxes content. Five worm species were identified in bait boxes with foreign species: Glycera dibranchiata, Namalycastis rhodochorde, Perinereis cultrifera, Perinereis lines, and Sipunculus (Sipunculus) nudus. The examination of bait boxes in Portugal suggested that there is a low risk of associated hitchhiker species introduction and dissemination, mostly because of packaging procedures, which should be advised. The same is not true to the non-indigenous live bait species. (C) 2017 Elsevier Ltd. All rights reserved:
- Anelídeos poliquetas como isco vivo: caracterização da atividade de apanha em ambientes salobros costeiros PortuguesesPublication . Fidalgo E Costa, Pedro; Sá, Erica; Alves, Ana Sofia; Cabral, Sara; Castro, Nuno; Picard, David; Castro, João J.; Cancela Da Fonseca, Luís; Chainho, Paula; Canning-Clode, João; Pombo, Ana Margarida; Costa, José LinoA captura de isco vivo para a pesca, efetuada em sedimentos intertidais, tem aumentado em todo o Mundo, pois face ao incremento da procura, constitui uma importante fonte de rendimento para as populações que vivem junto à costa. Macroinvertebrados, tais como, moluscos, crustáceos e anelídeos poliquetas, entre outros, são capturados em muitos sistemas estuarinos portugueses, sendo a dimensão real das capturas subestimada. Este é o caso das capturas de anelídeos poliquetas para utilização, quer como isco vivo, quer como suplemento alimentar em atividades de aquacultura.Com o intuito de estimar o esforço da apanha de isco, espécies-alvo, técnicas e ferramentas utilizadas nesta atividade e as características dos apanhadores (número, idade e género), foram escolhidos como locais de estudo os estuários do Tejo e do Sado e as Rias de Aveiro e Formosa, no âmbito do projeto“Anelídeos Poliquetas como Isco Vivo em Portugal: Gestão da Apanha, Importação e Cultivo”, financiado pelo Programa PROMAR. Os resultados obtidos nestes sistemas mostraram que: i) os apanhadores de moluscos bivalves foram claramente maioritários no Estuário do Tejo e nas Rias de Aveiro e Formosa.
- Polychaete annelids as live bait in Portugal: harvesting activity in brackish water systemsPublication . Cabral, Sara; Alves, Ana Sofia; Castro, Nuno; Chainho, Paula; Sá, Erica; Cancela Da Fonseca, Luís; Fidalgo e Costa, Pedro; Castro, João; Canning-Clode, João; Pombo, Ana; Costa, José LinoPolychaete annelids are some of the most heavily harvested invertebrates collected in coastal areas and estuaries for their economic value as live fishing bait or as food supplement in aquaculture activities. However, information on bait digging in Portugal is scarce or incomplete. Thus, the present study aimed at investigating the bait digging activity in the four most relevant brackish water systems in Portugal: Ria de Aveiro and Ria Formosa coastal lagoons and Tagus and Sado estuaries. Direct observations were performed in each brackish water system 1 h and a half before and after the diurnal low spring tide (< 0.8 m height), on working days. Additionally, logbooks were delivered to bait diggers and two types of surveys were conducted in every system: one to all the intertidal users and the other only to bait diggers. The estimated daily weighted number of bait diggers varied between 31 in the Tagus estuary and 69 in the Ria Formosa coastal lagoon. Diopatra neapolitana (Delle Chiaje, 1841) was the main target species in Ria de Aveiro (more than 83%), Tagus estuary (more than 60%) and Ria Formosa (more than 90%), while in Sado estuary most of the bait diggers targeted Marphysa sp. (92.6%). The highest and lowest amount of polychaete annelid catches were estimated for Ria de Aveiro coastal lagoon (almost 50 tons per year) and Tagus estuary (11 tons per year), respectively. A total annual bait catch value in these four systems was estimated as €3.84 millions. The most important brackish water systems concerning bait diggers’ number and bait captures were Sado estuary and Ria de Aveiro coastal lagoon where management measures should be considered, although managing polychaete harvesting activity is still difficult due to limited information on harvesting and on direct and indirect impacts on population dynamics.