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- The EU landing obligation and European small-scale fisheries: What are the odds for success?Publication . Veiga, Pedro; Pita, C.; Rangel, Mafalda; Gonçalves, J. M. S.; Campos, Aida; Fernandes, P. G.; Sala, Antonello; Virgili, M.; Lucchetti, A.; Brcic, J.; Villasante, S.; Ballesteros, Marta A.; Chapela, R.; Santiago, Jose Luis; Agnarsson, S.; Ögmundarson, O.; Erzini, KarimA landing obligation was formally implemented in the European Union (EU) for the first time, as part of the recent reform of the EU Common Fisheries Policy (CFP). Given the reasonable success of the landing obligation in some countries such as the Faroe Islands, Iceland and Norway, this policy is seen as a viable approach to tackle the long-recognized discarding problem in EU waters. However, there has been some debate on whether there is sufficient evidence to support the feasibility of such a measure in the EU-CFP. The EU landing obligation will implicitly include all small-scale fisheries (SSF) provided the species captured are subject to catch limits or minimum sizes (in the case of the Mediterranean). SSF were included irrespective of the fact that the discarding problem in the EU has been historically associated with medium- to large-scale fleets (in particular largely mixed species trawl fisheries). Additionally, past experiences with a discard ban policy are still limited to specific countries and/or specific fisheries. This paper examined the appropriateness and feasibility of the recently implemented EU landing obligation in SSF. The effects in the long-term are unpredictable, but available evidence suggests that in the short to medium-term a landing obligation is likely to bring more negative social, economic and ecological impacts than benefits. (C) 2015 Elsevier Ltd. All rights reserved.
- Is Europe ready for a results-based approach to fisheries management? The voice of stakeholdersPublication . Santiago, Jose Luis; Ballesteros, Marta A.; Chapela, Rosa; Silva, Cristina; Nielsen, Kare N.; Rangel, Mafalda; Erzini, Karim; Wise, Laura; Campos, Aida; Borges, Maria F.; Sala, Antonello; Virgili, Massimo; Vidarsson, Jonas R.; Baudron, Alan; Fernandes, Paul G.The reformed Common Fisheries Policy (CFP), adopted by the European Union in 2013, aims to achieve sustainable exploitation of marine resources. Beyond the mainstream of stakeholders' engagement, the literature increasingly calls for shared accountability in fisheries management. In such scenarios, identifying stakeholders' insights becomes critical for a successful design of innovative management approaches. This paper analyses how the stakeholders perceive a results-based management system for four fisheries in different European sea-basins as well as at a pan-European level. The results indicate a need for adaptive and participatory management approaches, building on regional adaptations within transparent and plural frameworks for fisheries. To succeed, the system should explicitly address its associated public and private costs; neither participation nor accountability comes for free. (C) 2015 Elsevier Ltd. All rights reserved.
- Effects of reallocating fishing effort from trawling to creels in a Norway lobster fisheryPublication . Eichert, Moritz; Campos, Aida; Fonseca, Paulo; Lopes, Pedro; Marques, Lino; Castro, MargaridaThe consequences of reallocating fishing effort from trawling to creels in an area off the West coast of Portugal for the operation of the trawl fleet, as well as on the population dynamics and the global catch value for a high valued species, the Norway lobster (Nephrops norvegicus) are evaluated. The results suggest that only small portions of the area of interest are used by the trawl fleet, opening the possibility for a trawl ban without major disruption of the trawling activity. Economic benefits are expected, since predictions two scenarios tested, heavy and moderate exploitation, indicate no loss of catch value with much lower operational costs. Social benefits to local communities can also be expected since a much lower investment is needed for creel fishing, making this fishery attractive to small local companies already operating in the region. The proposed ban is consistent with the ecosystem approach to fisheries management and the Common Fisheries Policy (CFP) where the transition towards more responsible fishing practices is encouraged.
- Size selectivity of diamond and square mesh cod ends for rose shrimp (Parapenaeus longirostris) and Norway lobster (Nephrops norvegicus) off the Portuguese south coastPublication . Campos, Aida; Fonseca, P.; Erzini, KarimThe effects of an increase in cod end mesh size from 55 to 60 and 70 mm and a change of mesh configuration from diamond to square mesh on the size selectivity for rose shrimp Parapenaeus longirostris and Norway lobster Nephrops norvegicus captured off the Portuguese south coast were evaluated. The results were analysed taking into account between-haul variation in selectivity, and indicate a significant increase in L-50 for rose shrimp with an increase in mesh size or with the use of a square mesh cod end, while for Norway lobster only mesh configuration was found to affect this parameter. Two other important external variables were identified; the trawling depth and the cod end catch, which influence between-haul variation, by increasing the selection range for rose shrimp and Norway lobster, respectively. The results obtained suggest that an increase in the current minimum mesh size of 55 mm would be advisable for rose shrimp in order to respect the minimum landing size of 24 mm carapace length presently established for this species. Moreover, trawling for rose shrimp should be avoided at depths above 200 m, in order to avoid catches consisting almost exclusively of juveniles. Such an increase in mesh size would have a minor impact in terms of losses of individuals above the minimum landing size for Norway lobster and would contribute to reducing the amount of discards in this fishery. (C) 2002 Elsevier Science B.V. All rights reserved.
- The influence of dredge design on the catch of Callista chione (Linnaeus, 1758)Publication . Gaspar, Miguel; Dias, M. D.; Campos, Aida; Monteiro, C. C.; Santos, M. N.; Teodosio, Maria; Chícharo, LuísTo evaluate a possible introduction of a new dredge in the fishery of Callista chione (Linnaeus, 1758), IPIMAR has conducted a study with the objective of comparing the efficiency of two dredges (traditional dredge and the new dredge design) and evaluating their impact on the benthic community. The experiments were carried out during March 1999 on the Southwest coast of Portugal, from a site off Troia. Three different tow durations of 5, 10 and 20 min were investigated. A total of 24 hauls were accomplished, 4 for each tow duration and dredge. The experiments were conducted by attaching a cover bag with a 20 mm mesh to the gear. After each haul, the catches in the bag and in the cover were sorted separately. All individuals retained were attributed scores on a scale of 1–4 in which 1 equates to good and 4 equates to dead. The results obtained showed that catches from the traditional dredge (TD) are composed of a great fraction of juveniles of C. chione, while in the new dredge (NDD) catches are composed, almost entirely, by individuals with a superior size to the minimum legal length (50 mm). This result indicates that the mesh of the bag of the TD used in the exploitation of this resource is not adequate. For the 3 different tow durations, the mean fishing yield obtained for the NDD was always superior to the TD, due to its greater efficiency in capture. The proportion of by-catch is significantly higher when the TD is used. For all 3 tow duration, the TD caused mortalities on the target species and on the macrobenthic community in the same order of magnitude as the NDD. Since the fishery of C. chione is managed by daily quotas per boat, when using the NDD the impact on the macrobenthic community is reduced by about 50% due to its greater efficiency of capture. Another advantage in the usage of the NDD relatively to the TD, is to allow the smallest individuals (independently of the species) to escape rapidly through the metallic bars on the grid, increasing their probability of survival.
- Spatial patterns of fishing activity inside the Gorringe bank MPA based on VMS, AIS and e-logbooks dataPublication . Campos, Aida; Leitão, Pedro; Sousa, Luís; Gaspar, Patrícia; Henriques, VictorIn this study, the fishing distribution and intensity over the Gorringe bank, a large oceanic underwater mountain located in the NE Atlantic, Natura 2000 Network MPA inside Portugal's EEZ is evaluated in the period from 2012 to 2016. Based on the combined analysis of fisheries-dependent data comprising Vessel Monitoring System (VMS), Automatic Identification System (AIS) and electronic logbooks available for the Portuguese fleet oper-ating within the area, it was possible to identify fishing trips and fishing events and define fishing trajectories, allowing the estimation of the fishing effort and the CPUE at a high spatial resolution. A total of 32 Portuguese vessels were identified to have undertaken fishing activity within the limits of this MPA, mainly longliners based on mainland ports, operating drifting and bottom longlines on a seasonal basis. Fleet-related differences in the distribution and intensity of fishing effort and CPUE for the main target species were addressed. The bottom longline activity concentrated, as expected, around the two seamount summits, where the presence of VMEs and sensitive habitat-forming species have been registered. The analysis of AIS data, the only dataset made available in this study for non-Portuguese vessels, strongly suggests that the foreign fleet operating within the Gorringe MPA represents a significant fraction of the fishing activity in the area. If assessing the fishing impacts is deemed as an important objective in the management of this MPA, then the results obtained in this study can be a valuable contribution towards the environmental protection of this oceanic seamount.
- Size selectivity of diamond and square mesh cod ends for four by-catch species in the crustacean fishery off the Portuguese south coastPublication . Campos, Aida; Fonseca, P.; Erzini, KarimThe effects of an increase in cod end mesh size from 55 to 60 and 70 mm and a change of mesh configuration from 55 mm diamond to 55 turn square mesh on the size selectivity of four by-catch species (the red shrimp Aristeus antennatus, the European hake Merluccius merluccius, the horse mackerel Trachurus trachurus and the blue whiting Micromesistius poutassou) commonly captured in the crustacean fishery off the Portuguese south coast, were evaluated. Selectivity parameters for blue whiting, the most abundant species in the catches, were estimated taking into account between-haul variation, while for the remaining species, captured in much lower quantities, the selectivity estimates were based on pooled data by length class for all hauls within the same cod end. Length at 50% retention, L-50, was found to increase with mesh size and with the change in mesh configuration for all the studied species. For blue whiting trawling depth and cod end catch were found to play a role in between-haul variation by increasing L-50 as well. The results suggest that an increase in the current minimum mesh size of 55-70 mm would be advisable to be compatible with the minimum landing sizes (MLSs) of 29 mm carapace length and 27 cm total length for red shrimp and hake, respectively, while it would greatly reduce the amount of discards, particularly those for blue whiting, that accounted for approximately 50% of the total catch weight. Horse mackerel was the only species for which the use of a larger mesh size would result in a significant escapement of individuals above the MLS of 15 cm. (C) 2002 Elsevier Science B.V. All rights reserved.
- Preliminary results on the use of semi-floating shrimp traps for the striped soldier shrimp, Plesionika edwardsii (Crustacea: Decapoda: Pandalidae), off the Algarve coast (southern Portugal)Publication . Eichert, Moritz; Campos, Aida; Fonseca, Paulo; Henriques, Victor; Castro, MargaridaThe present study provides an account of an experimental survey aiming at the evaluation of the catchability of the striped soldier shrimp, Plesionika edwardsii, using semi-floating shrimp traps off the Algarve coast (southern Portugal). Currently, this species is not targeted by the crustacean bottom trawl fleet, and preliminary results on product value suggest that this may become an economically viable new fishery. Preliminary results suggest that this fishery could contribute to the diversification of fixed gears of low environmental impact targeting deep-water crustaceans, in agreement with the objectives of both the Marine Strategy Framework Directive and the reformed Common Fisheries Policy. However, potential spatial conflicts with trawling. the unknown size of the resource and a necessary precautionary approach may limit the number of licences that can be granted.
- Using a modified Nordmøre grid for by-catch reduction in the Portuguese crustacean-trawl fisheryPublication . Fonseca, Paulo; Campos, Aida; Larsen, Roger B.; Borges, Teresa C.; Erzini, KarimBy-catch and discards are a common problem to all fisheries. Recent studies of the Portuguese crustacean-trawl fishery show that discards average 70% of the total catch. This situation poses a threat not only to the management of target and commercial fish by-catch species stocks, but also in terms of the ecosystem impact of the discarded species whose survival is generally low. Previous attempts to address this problem by using oblique separator mesh panels associated with square-mesh windows, or square-mesh windows alone, provided encouraging results, but these are unlikely to have commercial applicability at present. Therefore, we tested the efficiency of a modified Nordmøre grid in excluding some of the most captured non-commercial bycatch species, such as the blue whiting, Micromesistius poutassou, and the boarfish, Capros aper, evaluating simultaneously the losses of the crustacean target species (rose shrimp, Parapenaeus longirostris, Norway lobster, Nephrops norvegicus and red shrimp, Aristeus antennatus) and commercially valuable fish by-catch. A total of 41 valid hauls were carried out during 2001, and 15 in 2002 on board the R/V “Noruega”. Results from both years varied considerably, with higher by-catch exclusion rates, in weight, registered in the second survey (73–74 and 48–63% for blue whiting and boarfish, respectively). The corresponding percentage reduction for target species was 8–15% for the Norway lobster, 4–9% for rose shrimp and 7–10% for red shrimp. The level of exclusion of the non-commercial by-catch is encouraging, although short-term loss of Norway lobster, where the escapees comprised larger individuals, raises some concern with regards to fishers’ acceptance of mandatory use of grids.
- Modelling the impact of deep-water crustacean trawl fishery in the marine ecosystem off Portuguese Southwestern and South Coasts: I) the trophic web and trophic flowsPublication . Angeles Torres, Maria; Fonseca, Paulo; Erzini, Karim; Borges, Teresa C.; Campos, Aida; Castro, Margarida; Santos, Jorge Manuel Bastos; Costa, Maria Esmeralda; Marçalo, Ana; Oliveira, Nuno; Vingada, JoseThe concentration of the population in coastal regions, in addition to the direct human use, is leading to an accelerated process of change and deterioration of the marine ecosystems. Human activities such as fishing together with environmental drivers (e.g. climate change) are triggering major threats to marine biodiversity, and impact directly the services they provide. In the South and Southwest coasts of Portugal, the deep-water crustacean trawl fishery is not exemption. This fishery is recognized to have large effects on a number of species while generating high rates of unwanted catches. However, taking into account an ecosystem-based perspective, the fishing impacts along the food web accounting for biological interactions between and among species caught remains poorly understood. These impacts are particularly troubling and are a cause of concern given the cascading effects that might arise. Facing the main policies and legislative instruments for the restoration and conservation of the marine environment, times are calling for implementing ecosystem-based approaches to fisheries management. To this end, we use a food web modelling (Ecopath with Ecosim) approach to assess the fishing impacts of this particular fishery on the marine ecosystem of southern and southwestern Portugal. In particular, we describe the food web structure and functioning, identify the main keystone species and/or groups, quantify the major trophic and energy flows, and ultimately assess the impact of fishing on the target species but also on the ecosystem by means of ecological and ecosystem-based indicators. Finally, we examine limitations and weaknesses of the model for potential improvements and future research directions.
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