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- Identifying métiers using landings profiles: an octopus-driven multi-gear coastal fleetPublication . Szynaka, Monika; Erzini, Karim; Gonçalves, Jorge Manuel Santos; Campos, AidaThe multi-gear coastal vessels in the Algarve (South Portugal) own licenses for various fishing gears. However, it is generally uncertain what gears they use, which is problematic as each individual gear is responsible for unique impacts on the resources and the environment. In this study, landing profiles identified for the multi-gear coastal fleet (2012–2016) were used as support in defining potential métiers using k-mean clustering analysis (CLARA) along with information from past studies on métiers. The results showed that more than 50% of the vessels were engaged in the octopus fishery year-round, using traps, while a small percentage (~13%) were entirely dedicated to clam dredging. In general, gillnets (21%) were used to target monkfish, hake and bastard soles, while trammel nets (6%) were used to target cuttlefish, with some vessels alternating the fishing gears (either seasonally or annually) according to target species. The method for the initial characterization of this fleet’s métiers and its efficiency with limited data is discussed, as well as the utility of this segmentation in support of management advice.
- Fishers, let us talk: validating métiers in a multi-gear coastal fishing fleetPublication . Szynaka, Monika; Fernandes, Mariana; Anjos, Mariana; Erzini, Karim; Gonçalves, Jorge Manuel Santos; Campos, AidaIn the multi-gear coastal fleet in the Algarve (South Portugal), fishers own licenses for various fishing gears. However, they generally do not use all these licenses, and therefore, it is difficult to estimate the impacts this fleet has on the local environment. In this study, two types of questionnaires were used directed to the local fishers from the multi-gear fleet during interviews carried out between November 2019 and July 2021 with the objective to validate the métiers proposed for this fleet in a previous study using multivariate analysis on past landing profiles. A total of 10 out of the 11 proposed métiers were validated, including four métiers with gillnets, three with dredges, two with trammel nets, and one with traps. Additional métiers were identified not found in the previous study. The results obtained with the two types of questionnaires are presented, and their usefulness in validating the gear used and the seasonality of fishing activities are discussed, as well as their contribution to a clearer distinction between target species and commercial by-catch.
- Reducing invertebrate by-catch in a coastal fishery using a raised monofilament trammel netPublication . Monika Jadwiga Szynaka; Pedro Monteiro; Karim Erzini; Jorge M.S. Gonçalves; Aida Campos; Szynaka, Monika Jadwiga; Monteiro, Pedro; Erzini, Karim; Gonçalves, Jorge Manuel Santos; Campos, AidaTrammel nets are one of the least selective fishing gears and are known to catch a variety of species, many of which are discarded, including important invertebrates that are considered habitat-forming species. Although there are few studies focusing on this type of by-catch, these habitat-forming species include corals and sponges that are vulnerable to disturbances from fishing activities using bottom contact gear. Experimental fishing was conducted off the port of Portimao (southern Portugal) from November 2021 to April 2022 using standard and modified trammel nets rigged to be lifted off the bottom with the objective of reducing invertebrate by-catch and impacts on the bottom habitat. The modified lifted net caught 36% less by-catch of invertebrates in numbers than the standard net, with no significant decrease of biomass and value of target species. The results obtained with the two net types are discussed, as well as the necessity for good video recording equipment that can improve sampling accuracy, and the usefulness of interviewing the fishers on net performance after experimental fishing was conducted.