Browsing by Author "Coll, Marta"
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- Consumption rates and interaction with fisheries of Mediterranean common dolphins in the Alboran SeaPublication . Giménez, Joan; Authier, Matthieu; Valeiras, Julio; Abad, Esther; Marçalo, Ana; Coll, Marta; Gauffier, Pauline; Santos, M. Begoña; de Stephanis, RenaudCommon dolphins (Delphinus delphis) are top predators, feeding on a wide variety of prey species, several of which are also targeted by fisheries. The last remaining healthy group of the endangered Mediterranean common dolphin subpopulation is located in the Alboran Sea. Their feeding grounds overlap with the fishing grounds of trawlers targeting European hake (Merluccius merluccius) and blue whiting (Micromessistius poutassou) as well as purse seiners targeting small pelagic species such as European sardine (Sardina pilchardus), European anchovy (Engraulis encrasicolus), horse mackerel (Trachurus spp.) and mackerel (Scomber spp.). In the present study, we estimated that individual common dolphins in the Alboran Sea have a food consumption of 3.35 +/- 0.67 kg/day, based on scaling equations applied to stranded animals. This figure is similar to the ones reported for other European populations. Although common dolphins mainly feed on mesopelagic species of none or little commercial interest, they also feed on commercial species, which could lead to a potential conflict with fisheries in the area. We estimated common dolphins in the Alboran Sea could consume more than 16,000 tonnes of fish annually, including ca 7365 (95% CI: 3838-11,639) tonnes of Madeira lanternfish (Ceratoscopelus maderensis), 2,888 (1123-5223) tonnes of bogue (Boops boops), 2770 (879-5270) tonnes of European sardine, 1,850 (170-4116) tonnes of gobies (Gobiidae), and 1497 (65-3352) tonnes of European hake (reference period 2006-2011). Estimated sardine, anchovy and blue whiting consumption was low when compared to the landings in the area, however estimated hake consumption was above the reported hake landings in recent years (393.4 +/- 146 tonnes landed annually between 2006 and 2011). Additionally, direct interactions between common dolphins and main fisheries were evaluated in a total of 111 observed fishing trips (70 in trawlers and 41 in purse seiners) in the area. Although no bycatch of common dolphin was recorded, non-lethal interactions between dolphins and the fishing activity were detected from observations of this on-board observer program. These interactions, together with the high prevalence of stranding with signs of fishing interactions from the study area, may imply an additional threat to this endangered cetacean subpopulation. (C) 2021 Elsevier B.V. All rights reserved.
- Energy content of anchovy and sardine using surrogate calorimetry methodsPublication . Campanini, Claudia; Albo Puigserver, Marta; Gérez, Sara; Lloret-Lloret, Elena; Giménez, Joan; Pennino, Maria Grazia; Bellido, José María; Colmenero, Ana I.; Coll, MartaEuropean anchovy (Engraulis encrasicolus) and sardine (Sardina pilchardus) are crucial species for the marine ecosystem of the Northwestern Mediterranean Sea. They account for a high percentage of fish landings and they represent an important economic income for the fishery sector. Concerns over their stock status are rising in recent years as biomass, growth, reproductive capacity, and body condition of both species are declining, with latitudinal variations. Therefore, there is an urgent need for a body condition monitoring scheme. Energy storage variability has important implications for both fish recruitment and population structure. Direct condition indices, such as energy density (ED) with bomb calorimetry, are highly reliable for measuring the energy content, but time-consuming. Alternatively, fatmeter analysis and relative condition index (Kn) have been proposed as effective indirect methods. The aim of this study is to test the application of fatmeter as a surrogate of bomb calorimetry to infer the energy content of sardine and anchovy. To validate its use, fatmeter values were compared with both ED and Kn values. Individuals of both species were sampled monthly for a year in order to assess seasonal variations in energy content. Our results highlight that fatmeter measurements are strongly correlated with calorimetry ED for sardine, while a weaker but significant correlation was found for anchovy. The observed differences between the two species are related to their breeding strategies. Based on this study, Kn cannot be considered a good proxy of the energy density of sardine, in particular during the resting period. By contrast, fatmeter analysis appears to be a faster and suitable method to evaluate the energy content of both species routinely. In addition, we provide a linear model to infer ED from fatmeter values for both small pelagic fish. Eventually, these findings could be used to implement body condition monitoring protocols and boost continuous large-scale monitoring.
- Fishers' perceptions about the EU discards policy and its economic impact on small-scale fisheries in Galicia (North West Spain)Publication . Villasante, Sebastian; Pierce, Graham J.; Pita, Cristina; Pazos Guimerans, César; Garcia Rodrigues, João; Antelo, Manel; Da Rocha, José Maria; Garcia Cutrini, Javier; Hastie, Lee C.; Veiga, Pedro; Sumaila, U. Rashid; Coll, MartaThis paper investigates the impact of the European Union landing obligation in the Galician (North West of Spain) multispecies small-scale gillnet fishery. By combining results from semi-structured interviews with small-scale fishers and a bioeconomic model, we found that the percentage of discards for small-scale fisheries is usually low, which is consistent with general empirical observations globally but can be high when quotas are exhausted. Our results also confirm that the landing obligation would generate negative impacts on fishers' activities by investing more time on-board to handle previously discarded fishes, and putting at risk the security of fishers at sea due to full use of allowable storage on-board coupled with often adverse sea conditions in Galician bays. The application of the landing obligation policy to small-scale fisheries would result in short-and long-term losses of fishing days and yields, with high negative impacts on sustainable fisheries such as the Galician multi species small-scale gillnet fishery. The expected number of fishing days under the landing obligation is estimated to be reduced by 50% during the five years following the implementation of the policy. The future yield (catches) under the landing obligation would be only 50% of catches expected in the absence of the landing obligation, regardless of the total volume of quotas allocated to the fleet. (C) 2016 Elsevier B.V. All rights reserved.
- Modelling the spatial distribution of Sardina pilchardus and Engraulis encrasicolus spawning habitat in the NW Mediterranean SeaPublication . Gordó-Vilaseca, Cesc; Pennino, Maria Grazia; Albo Puigserver, Marta; Wolff, Matthias; Coll, MartaWe investigated the main drivers of eggs and larvae distributions of European sardine and anchovy from the NW Mediterranean Sea. We used Generalized Additive Models and satellite environmental data. Mainly sea surface temperature, but also currents, surface height, and primary production were significantly correlated with both species' early stages distributions. Anchovy optimal temperature upper limit was not detected, but sardine eggs and larvae presented a small-ranged bell-shape curve relationship to SST with an upper SST threshold around 13 degrees C. Sardine spawning during winter appeared to be dependant not only on in-situ environmental conditions but also on summer conditions prior to the spawning event. Model predictions of the larval and spawning habitat distribution showed clear differences between developmental stages and between species, confirming a worsening of the sardine habitat with time. Considering the further increase of surface temperature predicted in the years to come, the survival of the sardine in the region could be compromised.
- Sowing potential transformative changes in the fishing and agrifood systems – conference reportPublication . Moranta, Joan; Florido-del-Corral, David; López-López, Lucía; Gómez, Sílvia; Agujetas, Julio; Albo Puigserver, Marta; Brent, Zoe W.; Bathily, Lamine; Calvário, Rita; Cavalli, Marta; Coll, Marta; Crane, Annya; de Oliveira, Ericka C.L.; Ertör, Irmak; Herrera-Racionero, Paloma; Leitão, Francisco; Miret-Pastor, Lluís; Patraca, Beatriz; Ortega, Miquel; Pascual-Fernández, José J.; Ramón-Bruquetas, Jaime; Sáez-Jiménez, Jorge; Seck-Papalaye, Abdoulaye; Villasante, SebastiánThe need to better understand the trade-offs between food production, trade and consumption; social and environmental impacts of food systems and food health requirements remains a challenge. Additionally, there is an urgency to transform the food system to reach the dietary patterns required to address the current diet -environment-health trilemma. Transformative changes are required to deal with the food system crisis. To this end, it is necessary to strengthen the links in the food chain and establish solid alliances between production and consumption with the objective of designing alternative food systems. In this context, the Agroecosystems History Laboratory of Pablo de Olavide University and Alimentta-Think tank for the transition of agrifood sys-tems, organised the IX International Congress of Agroecology between the 19th and the 23rd of January, 2023, in Seville (Spain). Its theme was "Cultivating local agroecological-based food systems". Within the Congress, a hybrid panel of "Sowing initiatives with transformative potential in the fishing sector" was held to bring together initiatives with the capacity to generate transformative changes and enhance the value of fisheries in the field of agroecology and food sovereignty. The panel included communications related to seafood consumption, food sovereignty, co-management, inequalities, collaborative experiences, waste management, transformation pro-cessing and commercialisation. As a conclusion of the panel, a new perspective is required to redesign the agrifood systems and promote desirable multiple transformative changes that help to establish analytical and political action strategies in the field of fisheries as a food system.
- Strong fisheries management and governance positively impact ecosystem statusPublication . Bundy, Alida; Chuenpagdee, Ratana; Boldt, Jennifer L.; Borges, Maria de Fatima; Camara, Mohamed Lamine; Coll, Marta; Diallo, Ibrahima; Fox, Clive; Fulton, Elizabeth A.; Gazihan, Ayse; Jarre, Astrid; Jouffre, Didier; Kleisner, Kristin M.; Knight, Ben; Link, Jason; Matiku, Patroba P.; Masski, Hicham; Moutopoulos, Dimitrios K.; Piroddi, Chiara; Raid, Tut; Sobrino, Ignacio; Tam, Jorge; Thiao, Djiga; Angeles Torres, Maria; Tsagarakis, Konstantinos; van der Meeren, Gro I.; Shin, Yunne-JaiFisheries have had major negative impacts on marine ecosystems, and effective fisheries management and governance are needed to achieve sustainable fisheries, biodiversity conservation goals and thus good ecosystem status. To date, the IndiSeas programme (Indicators for the Seas) has focussed on assessing the ecological impacts of fishing at the ecosystem scale using ecological indicators. Here, we explore fisheries Management Effectiveness' and Governance Quality' and relate this to ecosystem health and status. We developed a dedicated expert survey, focused at the ecosystem level, with a series of questions addressing aspects of management and governance, from an ecosystem-based perspective, using objective and evidence-based criteria. The survey was completed by ecosystem experts (managers and scientists) and results analysed using ranking and multivariate methods. Results were further examined for selected ecosystems, using expert knowledge, to explore the overall findings in greater depth. Higher scores for Management Effectiveness' and Governance Quality' were significantly and positively related to ecosystems with better ecological status. Key factors that point to success in delivering fisheries and conservation objectives were as follows: the use of reference points for management, frequent review of stock assessments, whether Illegal, Unreported and Unregulated (IUU) catches were being accounted for and addressed, and the inclusion of stakeholders. Additionally, we found that the implementation of a long-term management plan, including economic and social dimensions of fisheries in exploited ecosystems, was a key factor in successful, sustainable fisheries management. Our results support the thesis that good ecosystem-based management and governance, sustainable fisheries and healthy ecosystems go together.