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Gonçalves, Jorge Manuel Santos

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  • Catches in ghost-fishing octopus and fish traps in the northeastern Atlantic Ocean (Algarve, Portugal)
    Publication . Erzini, Karim; Bentes, L.; Coelho, Rui; Lino, P. G.; Monteiro, P.; Ribeiro, J.; Gonçalves, J. M. S.
    Ghost fishing is the term used to describe the continued capture of fish and other living organisms after a fisherman has lost all control over the gear. Traps may be lost for a variety of reasons including theft, vandalism, abandonment, interactions with other gear, fouling on the bottom (i.e., traps and ropes are caught on rocky substrate), bad weather, and human error (Laist, 1995). Annual trap loss can be as high as 20% to 50% of fished traps in some fisheries (Al-Masroori et al., 2004). Because lost traps can continue to fish for long periods, albeit with decreasing efficiency over time (e.g., Smolowitz, 1978; Breen, 1987, 1990; Guillory, 1993), ghost fishing is a concern in fisheries worldwide.
  • Soft-bottom fishes and spatial protection: findings from a temperate marine protected area
    Publication . Sousa, Inês; Gonçalves, Jorge Manuel Santos; Claudet, Joachim; Coelho, Rui; Gonçalves, Emanuel J.; Erzini, Karim
    Numerous studies over the last decades have focused on marine protected areas (MPAs) and their effects on fish communities. However, there is a knowledge gap regarding how species that live associated with soft-substrates (e.g., sand, mud) respond to spatial protection. We analyzed abundance, biomass and total lengths of the soft-bottom fishes in a multiple-use MPA in the north-eastern Atlantic, the Luiz Saldanha Marine Park (Portugal), during and after the implementation of its management plan. Data were collected by experimental fishing in areas with three different levels of protection, during the implementation period and for three years after full implementation of the MPA. Univariate analysis detected significant biomass increases between the two periods. Fish assemblages were mainly structured by depth and substrate, followed by protection level. Community composition analyses revealed significant differences between protection levels and between the two periods. Species exhibited a broad variation in their response to protection, and we hypothesize that factors such as species habitat preferences, body size and late maturity might be underlying determinants. Overall, this study provides some evidence of protection effectiveness in soft-bottom fish communities, supported by the significant increase in biomass in the protected areas and the positive trends of some species.
  • First record of Ocinebrina nicolai (Mollusca: Gastropoda: Muricidae: Ocenebrinae) in North-Eastern Atlantic waters
    Publication . Afonso, Carlos; Bonomolo, Giuseppe; Monteiro, Pedro; Bentes, Luis; Oliveira, Frederico; Veiga, Pedro; Rangel, Mafalda; Sousa, Inês; Leite, Laura; Gonçalves, J. M. S.
    Ocinebrina nicolai Monterosato, 1884 a marine mollusc belonging to the Muricidae family is reported from Algarve, south coast of Portugal for the first time and is a new record for the biodiversity of the Portuguese malacological fauna and northeastern Atlantic waters. This species with a medium-size shell for the genus (14–16 mm) was initially sampled during a baseline project that studied marine biotopes in the central Algarve region. This short note presents a brief diagnosis of the species, provides local information on geographical distribution, habitat, and compares it with other congeneric species found in Portugal: Ocinebrina aciculata (Lamarck, 1822) and Ocinebrina edwardsii (Payraudeau, 1826).
  • Transboundary dimensions of marine spatial planning: Fostering inter-jurisdictional relations and governance
    Publication . Jay, Stephen; Alves, Fátima L.; O'Mahony, Cathal; Gomez, Maria; Rooney, Aoibheann; Almodovar, Margarida; Gee, Kira; Suárez de Vivero, Juan Luis; Gonçalves, J. M. S.; da Luz Fernandes, Maria; Tello, Olvido; Twomey, Sarah; Prado, Inmaculada; Fonseca, Catarina; Bentes, L.; Henriques, Guida; Campos, Aldino
    There is broad agreement that marine spatial planning (MSP) should incorporate transboundary considerations, reflecting the cross-border nature of marine and coastal ecosystem dynamics and maritime resources and activities. This is recognised in the European Union's recent legislation on MSP, and experience in transboundary approaches is developing through official processes and pilot studies.
  • Marxan as a zoning tool for development and economic purposed areas - Aquaculture Management Areas (AMAs)
    Publication . Sales Henriques, Nuno; Monteiro, Pedro; Bentes, Luis; Oliveira, Frederico; Afonso, Carlos; Gonçalves, Jorge Manuel Santos
    The increased number of human activities within the marine environment and the demand for maritime space has increased to a point where in some parts of the globe the demand for maritime space has exceeded the available area. The overlapping objectives and activities have caused severe conflicts among users and with the natural marine environment itself. For that reason, holistic strategies such as Ecosystem Based Management (EBM) and Maritime Spatial Planning (MSP) have been evolved and developed to sustainably manage the marine environment, avoiding conflicts and creating synergies. Spatial analysis tools like Marxan have been used for several years as decision support tools mostly for conservation plans, such as design and establishment of protected areas. In this study we approach the potential of this tool with a different purpose in mind: instead of using the available information of the region for the development of a conservation plan, we used this tool and the available information to select areas to establish Aquaculture Management Areas (AMAs). We also intended to analyse how the existing features of the region would affect the final result of a spatial plan aimed to establish areas for economic and development purposes. We conclude that the use of Marxan can be advantageous to support the planning and development of coastal regions, not only in a conservationist point of view (as it has been mostly used), but also into a developing and economic driven approach. This tool can be particularly useful in regions or situations where there is a large number of stakeholders, ecological and geographical features that could potentially conflict with the establishment, the management and the success of the proposed management areas. (C) 2017 Elsevier Ltd. All rights reserved.
  • 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, Karim
    A 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.
  • Feeding habits of the deep-snouted pipefish Syngnathus typhle in a temperate coastal lagoon
    Publication . Oliveira, F.; Erzini, Karim; Gonçalves, J. M. S.
    Feeding habits of Syngnathus typhle were determined based on monthly sampling during experimental fishing in a coastal lagoon (Ria Formosa, South Portugal) from April 2004 to May 2002. The gut contents of 856 individuals were analysed and quantified with numerical and gravimetric methods, as well as with some complementary indices and measures (vacuity, fullness and relative importance). In this study, this species fed mainly on Copepoda, Mysidacea, small caridean grass shrimps (Hippolytidae and Palaemonidae) and small fishes (Gobiidae) and to a lesser degree on other small invertebrates. No significant differences were found between the diets of males and females. However, significant differences in the fullness indexes of both sexes were observed during the reproductive period. Significant differences in the diet among seasons were also verified but no seasonal trends were discovered. Snout length showed a linear increase with growth while mouth area and total length displayed an allometric relation. Mouth shape varied between an ellipse and an almost perfect circle. The increase in mouth area and snout length as S. typhle grows contributed to the observed ontogenic diet shift with specimens smaller than 10 cm feeding almost exclusively on Copepoda, medium sized specimens feeding mainly on Hippolytidae and Mysidacea, while larger specimens preyed on Hippolytidae, Palaemonidae and Gobiidae. Prey size generally increased with size of S. typhle. (c) 2007 Elsevier Ltd. All rights reserved.
  • Interactions between air-breathing marine megafauna and artisanal fisheries in Southern Iberian Atlantic waters: results from an interview survey to fishers
    Publication . Alexandre, Sofia; Marçalo, Ana; Marques, Tiago A.; Pires, Alexandra; Rangel, Mafalda; Ressurreição, Adriana; Monteiro, Pedro; Erzini, Karim; Gonçalves, Jorge Manuel Santos
    The coastal waters off Western Iberia are an important fishing ground and a marine megafauna foraging area. Overlap between fishery target species and the diet of several air breathing marine megafauna species can lead to negative interactions and consequently conservation and economic issues. This work aimed to assess marine megafauna (cetaceans, marine birds, and marine turtles) – fishery interactions through face-to-face interviews to fishers of the local and coastal artisanal fisheries fleets in the landing sites of the Portuguese mainland Southern coast (Algarve). The main goal was to identify and evaluate problematic interactions known to cause bycatch or economic loss through depredation. We found that bycatch is a concern for all marine megafauna groups, but depredation problems are mostly associated with cetaceans. Of the sampled artisanal fisheries (longlines, pots and traps, bottom set-nets, and purse seine), the fishing gears of most concern were purse seine and coastal bottom set-nets. Purse seine showed problems associated with important bycatch numbers, especially of common dolphins, Delphinus delphis, while bottom set-nets have considerable bycatch of all animal groups and depredation was highly associated with bottlenose dolphins, Tursiops truncatus. Bycatch and depredation were found to be species, gear, area, and vessel size dependent. Economic loss caused by depredation led to catch and gear damage and was widely reported by bottom set-net fishers, ranging from 7% to 21% of their revenue. Higher losses were reported for local vessels in leeward (eastern) Algarve area. This study showed that the active participation of fishers provides improved localized knowledge on interactions between local and coastal fisheries and marine megafauna, allowing for the definition of specific management and mitigation strategies.
  • Length-weight relationships of six syngnathid species from Ria Formosa, SW Iberian coast
    Publication . Vieira, RP; Monteiro, P.; Ribeiro, J.; Bentes, L.; Oliveira, F.; Erzini, Karim; Gonçalves, J. M. S.
    In this study, the length-weight (LWR) parameters were estimated for six syngnathid species, including 2 seahorses and 4 pipefishes, from Ria Formosa, a temperate lagoon from the south coast of Portugal. A total of 5070 fishes were used to determine the LWR. The estimated b value ranged from 2.95 (Nerophis ophidion) to 3.36 (Syngnathus abaster). To the authors' best knowledge, LWR parameters were estimated for the first time for Nerophis ophidion and Syngnathus typhle for the Atlantic waters. Data here present are essential for management and conservation of these flagship species.
  • Identifying persistent hot spot areas of undersized fish and crustaceans in southern european waters: implication for fishery management under the discard ban regulation
    Publication . Milisenda, Giacomo; Garofalo, Germana; Fiorentino, Fabio; Colloca, Francesco; Maynou, Francesc; Ligas, Alessandro; Musumeci, Claudia; Bentes, Luis; Gonçalves, Jorge Manuel Santos; Erzini, Karim; Russo, Tommaso; D’Andrea, Lorenzo; Vitale, Sergio
    The recent establishment of the "landing obligation" under the reformed EU Common Fishery Policy has the twofold objective of reducing the excessive practice of discarding unwanted catch at sea and encouraging more selective and sustainable fisheries. Within this context, the awareness of the spatial distribution of potential unwanted catches is important for devising management measures aimed to decrease discards. This study analyzed the distribution of Hot Spot density areas of demersal fish and crustaceans below the Minimum Conservation Reference Size (MCRS) in four different southern European seas: continental Portuguese coast, Catalan Sea, South of Sicily, Liguria and northern Tyrrhenian Seas using both bottom trawl survey data and information on the spatial distribution of commercial fisheries. Critical areas for discarding were identified as zones where the highest densities of individuals below MCRS were consistently recorded throughout a series of years. Results clearly showed a patchy distribution of undersized individuals in each investigated area, highlighting the overlap between high density patches of both discards and fishing effort. The present findings provide a relevant knowledge for supporting the application of spatial-based management actions, such as the designation of Fisheries Restricted Areas (FRAs), in order to minimize the by-catch of undersized specimens and improve the sustainability of demersal fisheries