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The spatial distribution of deep-sea fishes is commonly related to major water masses or regional circulatory features that in turn may reflect differences in food-web structure and productivity. Aphanopus carbo is a benthopelagic species that undergoes horizontal and vertical migrations driven by spawning and by feeding, and for which a large-scale clockwise migration around the NE Atlantic is hypothesized. In this work, the adequacy of otolith microchemical composition used as tool to discriminate A. carbo specimens caught at different areas was investigated. Furthermore, potential birth areas and spatial pattern migration throughout the species life cycle were studied. Trace element concentration (TEC) in the otolith edge allowed the discrimination of the locations where specimens were caught and supported the separation between the northern and the southern distribution areas. The existence of two natal sources was suggested based on the separation of otolith core TEC into two groups. Longitudinal multivariate analyses applied to TEC data also sustained the separation of the otoliths into two main groups, but the mixing between them gives support to the species migratory hypothesis. The acceptance of both southern and northern spawning grounds and of migratory movements along the NE Atlantic in both northward and southward directions implies changes to the current migratory hypothesis that might be translated into new definitions of A. carbo stock structure and therefore fisheries management., This work was supported by the Portuguese Foundation for Science and Technology (FCT – Fundação para a Ciência e Tecnologia) [Grant SFRH/BD/64434/2009 to I. Farias]; the Portuguese Fisheries Operational Program (2007–2013) (PROMAR – Programa Operacional Pescas), co-financed by the European Fisheries Fund (EFF) (2007–2013), under project CERTIFICA (2011–2015), MSC Certification in Portugal - Acquiring the knowledge and studying the viability for its application to coastal and artisanal fisheries; and the Portuguese Government Development Investments and Expenses Program (PIDDAC – Programa de Investimentos e Despesas de Desenvolvimento da Administração Central) under the EU/DG Fisheries' Data Collection Framework (DCF).

The spatial and temporal variation of the early growth patterns (EGP) of anchoveta (Engraulis ringens), were analyzed and compared among three geographic areas, i.e., Northern zone (18–24°S); North-central zone (26–30°S) and Southern zone (33–42°S) off the Chilean coast over three years (i.e., 2015, 2016 and 2019). EGP were determined through otolith microstructure analysis for juveniles ranging from 2.0 to 12.0 cm in total length (TL), corresponding to ages from 28 to 187 days. The comparative growth analysis between the three study areas for the 2015, 2016 and 2019 cohorts showed significant differences in the Laird-Gompertz growth parameters and the absolute growth rate at the inflection point (0.67–1.11 mmd−1). A generalized additive models (GAM) was used to analyze changes in mean daily increment width profiles (IW) as related to the area, monthly cohort, sea surface temperature (SST) and Chlorophyll concentration (Chloa) as predictive variables. The GAM did not show significant difference in mean IW between northern and north-central areas (7.9 ± 3.9 vs 8.3 ± μm), although they significantly varied with respect the southern area, where the lower values of IW were found (5.6 µm). The GAM showed higher IW partial residuals when SST was above 14 °C and Chloa concentration was lower than 2 m gm−3. Overall results showed a high plasticity in the early growth pattern of E. ringens, indicating interannual and spatial variability, with SST playing a pivotal role across a wide latitudinal gradient off Chilean coast.

The European hake Merluccius merluccius is the third most valuable species for the North-East Atlantic and the Mediterranean fisheries. European hake has been rated as overexploited in the Mediterranean, thus careful management is advisable. Mediterranean hake is well-differentiated from Atlantic hake, but sub-population structure within the Mediterranean, and how this structure could be translated into stocks (operative management units), is still an elusive topic. Otolith shape and chemistry (concentration of trace elements) have been systematically used to distinguish fish stocks. Our aim was therefore to assess the discrimination capability (assigning fish to the correct geographical unit) of otolith shape and microchemistry at two geographical scales within the Mediterranean: (1) the official geographical subareas (GSAs), and (2) three larger units previously suggested by genetic markers (i.e., Western Mediterranean, Adriatic with Central Mediterranean, and Eastern Mediterranean). Two complementary analyses were completed because shape is more easily analyzed than chemistry. First, a large sample of juvenile hake (n = 1656) from 40 Mediterranean GSAs subunits was used for shape analysis. Second, a subsample of those fish (n = 154) from 10 GSAs was analyzed for both otolith shape and microchemistry. Irrespective of the type of data (shape and/or chemistry) and geographical scale (GSAs versus the 3-units), between-unit differences were always statistically significant. However, according to the large within-unit variability, discrimination capability was always poor but better at the GSA scale, and even better when both shape and microchemistry were combined. Moreover, unsupervised clustering methods (the number and limits of the units are data-driven and not a priori defined as above) failed to find an optimal structure. Overall, these results are fully compatible with the hypothesis of a continuous gradient, within which discrete spatial units cannot be safely recognized., Sílvia Pérez-Mayol's salary was co-funded by the Direcció General de Política Universitària i Recerca of the Balearic Government, Spain and the Consejo Superior de Investigaciones Científicas, Spain (TEC/001/2018). Thibault Kersaudy’s salary was funded by the MED_UNITs contract. This study was part of the MED_UNITs contract (Specific Contract No. 03EASME/EMFF/2017/1.3.2.3/01/ SI2.793201 -SC03– MED_UNITs).

Assessing the motivations and wildlife-related value orientations (WVOs) of outdoor recreations, such as recreational fishing (RF), is of key importance to understand the human dimensions of natural resource use and to inform management actions. Using a national random telephone survey, we contrasted the participation rate, the socio-economical profile, and the motivations and WVO of the participants of RF, outdoor recreation (OR), consumptive outdoor recreation (COR), and indoor recreation (IR) in Spain. Participation rates of the four subgroups were 6.6, 15.3, 49.4, and 28.4%, for RF, COR, OR, and IR, respectively. The four subgroups differed in socio-economic characteristics, with women being substantially less involved in RF compared to COR, OR, and IR. Moreover, we found higher incomes and educational degrees of the participants in the three outdoor modalities compared to IR. Motivations to engage in RF, COR, OR, and IR were different. Recreational fishers placed significantly more importance on the motives “to be close to nature,” “to experience tranquility,” “to get away from the usual demands of life,” “to relax psychically,” “to stay with family,” and “to get exercise” compared to the other recreational groups, being very different from the ones to practice IR. We did not find significant differences in the WVO among the participants of the four recreational activities. We conclude that recreational fishing is a widespread recreational activity in Spain, embedded in all the segments of the society, thereby generating substantial psychological benefits, which are not equally produced by other forms of indoor and outdoor recreation., JA was supported by the Ramón y Cajal Grant (Grant no. RYC2018-024488-I), funded by the Spanish Ministry of Science and Innovation (MICINN), and he also received funding from the CLOCKS R&D Project (grant no. PID2019-104940GA-I00) funded by the MICINN and the Agencia Estatal de Investigación, and the intramural research project, JSATS (Grant no. PIE202030E002) funded by the MICINN and the Spanish National Research Council (CSIC). RA acknowledges funding from the German Ministry of Education and Research (marEEshift: 01LC1826D, Aquatag 033W046A).

10 pages, 6 figures, 5 tables, supplementary material https://doi.org/10.3989/scimar.05106.007, [EN] The age and growth patterns of the mesopelagic fish Ceratoscopelus maderensis (family Myctophidae) of the western Mediterranean Sea were described throughout its entire life cycle (from larvae to adult stages) using the sagittae otoliths of 59 individuals collected in December 2009. Three characteristic zones were identified along the cross-section of the sagittae (larval, metamorphic and juvenile-adult zones). Assuming growth rings as daily increments, the age of the analysed individuals (from 3.5 to 64 mm standard length [SL]) would range from 7 to 332 days. The relationship between the number of increments and the fish SL was fitted to a von Bertalanffy growth model (SL=70.5899×(1–exp(–0.0501(t+2.6705))). The growth pattern of C. maderensis in the western Mediterranean Sea was similar to that reported for this species in the northeast Atlantic Ocean. Though from a body size of 40-45 mm SL, growth rates declined more slowly in individuals from the western Mediterranean Sea, growth differences between these individuals and those from the northeast Atlantic Ocean were not statistically significant. This study provides new insights into the age and growth patterns of one of the most abundant mesopelagic fish species in the Mediterranean Sea that have clear implications for the study and management of marine ecosystems, [ES] En el presente trabajo se describen la edad y los patrones de crecimiento desde la fase larvaria hasta la fase adulta del pez mesopelágico Ceratoscopelus maderensis (familia Myctophidae) del Mediterráneo occidental. Para ello, se analizó el otolito sagitta de 59 individuos capturados en diciembre de 2009. Se identificaron tres zonas en la sagitta, cada una de las cuales se corresponde con una fase del desarrollo ontogenético del pez: larvaria, metamórfica y juvenil-adulta. Asumiendo que los anillos de crecimiento son diarios, la edad de los individuos analizados (de 3.5 a 64 mm de longitud estándar [SL]) oscilaría entre 7 y 332 días. La relación entre el número de incrementos y la SL de los peces se ajustó al modelo de crecimiento de von Bertalanffy (SL=70.5899×(1–exp(–0.0501(t+2.6705))). El patrón de crecimiento de C. maderensisen el Mediterráneo occidental fue similar al previamente descrito para esta especie en el Noreste del Océano Atlántico. A pesar de que, a partir de 40-45 mm SL, las tasas de crecimiento disminuyeron más lentamente en los individuos del Medi-terráneo occidental, las diferencias de crecimiento entre estos individuos y los del Noreste del Océano Atlántico no fueron estadísticamente significativas. Los resultados de este estudio aportan nuevos conocimientos sobre la edad y el crecimiento de una de las especies más abundantes del Mar Mediterráneo, lo cual tiene claras implicaciones de cara al estudio y la gestión de los ecosistemas marinos, The authors are very grateful to the IDEADOS project (CTM2008-04489-C03-02) and for the technical sup-port offered by José Manuel Fortuño (ICM) and Silvia Pérez-Mayol of the Sclerochronology Service at IME-DEA (UIB-CSIC), With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI)

[EN] We determined the efficacy of marking the otoliths of three small-sized progenetic gobies to validate their increment periodicity. These small gobies have high mortalities and rearing difficulties, making direct validation difficult. The otoliths were marked by immersing the fish in a bath of alizarin red S. The fishes were euthanatized and the number of increments in their otoliths laid down after the fluorescent mark were counted and compared with the number of elapsed days. The results validated the daily periodicity of Aphia minuta and Pseudaphya ferreri. The high mortality hindered the validation of Crystallogobius linearis., [ES] Se determinó la eficacia en el marcado de los otolitos de tres góbidos progenéticos de pequeña talla con el fin de validar la periodicidad en la deposición de los incrementos de crecimiento. Estos pequeños góbidos presentan altas mortalidades y dificultades en su cría, por lo que la validación directa de su crecimiento es difícil. Los otolitos fueron marcados con rojo de alizarina S (ALR). Los peces fueron eutanasiados y el número de incrementos depositados después del marcaje con el colorante fluorescente se contó y comparó con el número de días transcurridos. Los resultados obtenidos validaron la periodicidad diaria para Aphia minuta y Pseudaphya ferreri. La elevada mortalidad impidió la validación en Crystallogobius linearis., SP’s salary was cofunded by the DGPUR of the Balearic Govern-ment and the CSIC. This contribution is a result of the “Unidad Asociada IMEDEA-LIMIA”.

Este artículo contiene 24 páginas, 5 figuras, 3 tablas., This work is the result of an international research effort to determine the main impacts of the COVID-19 pandemic on marine recreational fishing. Changes were assessed on (1) access to fishing, derived from lockdowns and other mobility restrictions; (2) ecosystems, because of alterations in fishing intensity and human presence; (3) the blue economy, derived from alterations in the investments and expenses of the fishers; and (4) society, in relation to variations in fishers’ health and well-being. For this, a consultation with experts from 16 countries was carried out, as well as an international online survey aimed at recreational fishers, that included specific questions designed to capture fishers’ heterogeneity in relation to behavior, skills and know-how, and vital involvement. Fishers’ participation in the online survey (5,998 recreational fishers in 15 countries) was promoted through a marketing campaign. The sensitivity of the fishers’ clustering procedure, based on the captured heterogeneity, was evaluated by SIMPER analysis and by generalized linear models. Results from the expert consultation highlighted a worldwide reduction in marine recreational fishing activity. Lower human-driven pressures are expected to generate some benefits for marine ecosystems. However, experts also identified high negative impacts on the blue economy, as well as on fisher health and well-being because of the loss of recreational fishing opportunities. Most (98%) of the fishers who participated in the online survey were identified as advanced, showing a much higher degree of commitment to recreational fishing than basic fishers (2%). Advanced fishers were, in general, more pessimistic about the impacts of COVID19, reporting higher reductions in physical activity and fish consumption, as well as poorer quality of night rest, foul mood, and raised more concerns about their health status. Controlled and safe access to marine recreational fisheries during pandemics would provide benefits to the health and well-being of people and reduce negative socioeconomic impacts, especially for vulnerable social groups., This work was funded by the Xunta de Galicia (RECREGES II project under Grant ED481B2018/017, and Grupo de Referencia Competitiva GI-2060 AEMI, under Grant ED431C2019/11). PP acknowledges economic support of the project Grupo de Trabajo Sobre Pesca Marítima Recreativa en España, funded by the Fundación Biodiversidad of the Spanish Ministerio Para la Transición Ecológica y el Reto Demográfico, co-funded by the European Maritime and Fisheries Fund. SV acknowledges the financial support of the EQUALSEA project ERC Consolidator Grant Agreement No. 101002784 funded by the European Research Council, and the CYTED program for the ECOMAR Network. AML, CS, and MW have been co-funded by the European Commission’s Data Collection Framework (DCF). CS acknowledge founding from the Danish Rod and Net Fish License funds (Project No. 39122). The CCMAR affiliated authors acknowledge Portuguese national funds from FCT-Foundation for Science and Technology through project UIDB/04326/2020. MaR acknowledges FCT funding through a post-doctoral grant (SFRH/BPD/116307/2016). AA acknowledges funding of FAPES, Fundação de Amparo à Pesquisa e Inovação do Espírito Santo, Brazil - PROFIX program 10/2018 - T.O.: 348/2018 for AA postdoctoral scholarship. JR-F acknowledges funding of Participatory Fishing Monitoring accomplished by the ICHTUS Soluções em Meio Ambiente Ltda. KF was funded by the tourist fishing project (“Kartlegging av Turistfiske”), which is part of the Coastal Zone Ecosystem Program at the Institute of Marine Research of Norway. JG-C and VS were funded in part by a contract with the Regional Fisheries and Aquaculture Service - Autonomous Community of the Region of Murcia - Spain (with funds from the European Maritime and Fisheries Fund) and the project “MaReFish” financed by the MedPAN network under its “Small Projects – 2018” call. JA was supported by a Ramon y Cajal Grant (Grant No. RYC2018-024488-I) and received funding from the CLOCKS (Grant No. PID2019-104940GAI00) and JSATS (Grant No. PIE202030E002) projects funded by the Spanish Ministry of Science and Innovation (MICINN). VSB is supported by a “Juan de la Cierva Incorporación” research fellowship (IJC2018-035389-I) granted by the Spanish Ministry of Science and Innovation (MICINN). HS acknowledges financial support by the Federal Ministry of Education and Research of Germany in the framework of marEEshift (Project No. 01LC 1826B).

The reproductive biology of two species of pipefish, Syngnathus typhle and S. abaster, was investigated in western Mediterranean coastal waters, through determination of sex-ratio and maturity state, and histological assessment of gonads, brood pouch and embryos of these little-known syngnathid species. A total of 22 S. typhle and 13 S. abaster individuals were collected by towing-net on shallow seagrass meadows (Posidonia oceanica and Cymodocea nodosa) at Balearic Islands (Spain). Overall sex-ratio (male : female) was 1.0 : 1.2 for S. typhle and 1.0 : 2.7 for S. abaster. Regarding maturity, all stages of females were sampled while only immature or brooding males were collected. Males with embryos in the pouch were found in summer for both species, and mature females of S. typhle were found in summer whereas mature females of S. abaster were found in winter and summer, suggesting that each species might have a different reproductive cycle. This study contributes to the knowledge on the reproductive biology of the two most abundant pipefish species in W-Mediterranean coastal waters, which might help for further restocking and conservation management strategies., This study was partly funded by Proyecto Hippoparques (1541S/2015 and 1580S/2015; Organismo Autónomo de Parques Nacionales Ministerio de Agricultura, Alimentación y Medio Ambiente, Spain).

Pipefish are a vulnerable and diverse group of ichthyofauna tightly associated with seagrass meadows, key habitats in shallow marine areas. Despite their charismatic role, the main ecological features, habitat, and diet of this group remain largely unknown. This study focuses on assessing pipefish habitat and feeding preferences, including different hosting seagrasses such as Posidonia oceanica and Cymodocea nodosa from the Balearic Islands, western Mediterranean. Four species (Syngnathus typhle, S. abaster, Nerophis ophidion, and N. maculatus) were found associated to different seagrasses. S. typhle and N. maculatus were more frequent in P. oceanica meadows, while S. abaster and N. ophidion in C. nodosa. Individuals of all species captured in P. oceanica were larger than those living in C. nodosa, suggesting a size-dependent habitat preference. Feeding preferences, however, were driven by prey availability and fish features, e.g., head/snout morphology. For the first time in the western Mediterranean, a thorough description of the diet and potential prey of this group was carried out. Epifaunal assemblages (potential prey) were dominated in both habitats by harpacticoid copepods and gammarid amphipods, and they were also the primary prey according to stomach contents of all species. These results can contribute to future pipefish conservation and management actions, such as targeting crucial habitat identification and designing culture and reintroduction protocols., This study was funded by the research Project “Singnátidos de los Parques Nacionales de las Islas Atlánticas y del Archipiélago de Cabrera (541S/2015)” awarded to CSIC by Organismo Autónomo Parques Nacionales (Ministerio de Agricultura, Alimentación y Medio Ambiente, Programa Estatal de I+D+i Orientada a los Retos de la Sociedad, Plan Estatal de Investigación Científica y Técnica y de Innovación 2013-2016). Additional support was provided by the joint Associated Unit IMEDEA-LIMIA (Laboratorio de Investigaciones Marinas y Acuicultura, Dirección General de Pesca y Medio Marino, Govern Illes Balears).

The common dolphinfish (Coryphaena hippurus) is an epipelagic thermophilic species with a worldwide distribution in tropical and subtropical regions that is characterized by its migratory behavior and fast growth rates. This species is targeted by artisanal small-scale and recreational fisheries in most regions where it is found. This paper updates and analyzes the global scientific knowledge on the biology and ecology of this species, which was last revised at a regional level 20 years ago. This review showed an increase in knowledge about the population structure and regional differences in biological traits, in parallel with a notable lack of mechanistic and even empirical knowledge about the ecology of this species, which hampers a good understanding of the population dynamics and the potential impacts of environmental change. This paper also updates the information about the Mediterranean dolphinfish fishery, where the main four countries that exploit this species deploy 30% of fish aggregation devices (FAD) worldwide. The results suggest, among other effects, some temporal synchronicity in landings across countries, potential interannual stock movement affecting inter-country catches, diverging trends in prices and insufficient quality in the estimates of fishing effort. The authors propose a suite of specific measures to ameliorate this lack of knowledge and to better manage this complex living resource., Vicenç Moltó acknowledges a predoctoral grant funded by the Regional Government of the Balearic Islands and the European Social Fund. This work was partially funded by two FAO Projects: CopeMed phase II “Coordination to Support Fisheries Management in the Western and Central Mediterranean” and MedSudMed “Assessment and Monitoring of the Fishery Resources and the Ecosystems in the Straits of Sicily”, both co-funded by the Spanish and the Italian Ministries of Agriculture, Fishery and Food, and by the Directorate-General for Maritime Affairs and Fisheries of the European Commission (DG-MARE). The work was partially supported by project CERES (H2020, EU 678193).

Este artículo contiene 14 páginas, 4 figuras., The European Parliament is concerned about the lack of information on the relevance of nine million Europeans engaged in marine recreational fishing (MRF), committing Member States to encourage environmental and socioeconomic sustainability of the sector. The objective of this paper is to provide recommendations to guide research actions and management policies, based on the case of Spain, a key country because its complex administrative regimen and the intensive use of its coasts, including 900,000 recreational fishers. A review of the state of the knowledge was performed to identify research gaps, while governance challenges were identified in an International Symposium on MRF. In the last two decades research on MRF was remarkable (139 publications). However, public investment in research (€2.44 million in the same period) should be improved to cover knowledge gaps on socioeconomic relevance, on impacts on vulnerable species and on implications of global warming. The license system should be standardized to allow estimation of effort, catch and expenditure. Social networks, mobile applications, fisher ecological knowledge, and citizen science programs could help to develop cost-effective research and management. Sciencebased, adaptive policies should improve the allocation of resources between MRF and other stakeholders, introducing co-management to reduce conflicts., This work received funds from the Xunta de Galicia under the modality of Grupos de Referencia Competitiva (Grant ED431C2019/11), RECREGES I and II projects under Grants ED481B2014/034-0 and ED481B2018/017, and SICORE project, funded by the Fundación Biodiversidad, Ministerio para la Transición Ecológica, Gobierno de España, Pleamar program, which is cofounded by the European Maritime and Fisheries Fund. SV acknowledges the financial the European COST Action “Ocean Governance for Sustainability – challenges, options and the role of science,” the ICES Science Fund Project “Social Transformations of Marine Social-Ecological Systems,” and the CYTED program for the ECOMAR Network. JP-F received funds from the project “Governance challenges for sustainable small-scale fisheries: creating synergies with marine conservation and tourism” (GOBAMP II, CSO2013-45773-R), financed by Ministry of Economy and Competitiveness of Spain. JA was supported by a JDC postdoctoral research grant funded by the Spanish Ministry of Economy, Industry and Competitiveness (ref. IJCI-2016-27681) and a Ramon y Cajal Grant funded by the Spanish Ministry of Science, Innovation and Universities (grant no. RYC2018-024488-I).

Mediterranean small-scale fleets catch a substantial amount of untargeted fish that are sold at a low market price. Most of these catches are pooled into mixed-fish boxes (MFBoxes), which are usually labeled and sold as mixed-fish commercial categories (MFCategories). In this paper, we describe the MFBoxes and the MFCategories from the small-scale fleet of Mallorca Island in terms of species composition, size distribution and economic value. We used (i) daily sales records of MFCategories between 2004 and 2015 and (ii) a sample of 141 photographs of MFBoxes, collected over one year (2009–2010). MFCategories represent a non-negligible fraction of the landings, between 18 and 51 tons/year which represents 100–300 K€/year. Some of the sampled MFBoxes were sold as one of the three identified MFCategories, which differ in species composition, size and average price (3.9 €/kg for the category LARGE MORRALLA, 2.2 €/kg for SMALL MORRALLA and 7.0 €/kg for VARIAT). However, more than half (52%) of the sampled MFBoxes were actually labeled and sold not as MFCategories but as one of the most abundant species in the box. This strategy might seem unprofitable because the market price is lower for MFBoxes sold as non-mixed categories than for non-mixed boxes of the same category. However, we observed that the label itself does not affect the selling price, but species composition does. Therefore, when sorting fish into boxes, fishers may be trying to optimize the tradeoff between not selling some low-priced fish and mixing them with other more valued fish. This alternative marketing strategy should be explored in depth and properly assessed, not only to maximize profits but also to promote a zero-discard European policy., This research received funding from the European Commission’s Horizon 2020 Research and Innovation Programme under Grant Agreement No. 634495 for the project Science, Technology, and Society Initiative to minimize Unwanted Catches in European Fisheries (MINOUW). OPMallorcaMar and the Federació Balear de Confraries de Pescadors are thanked for their support and collaboration. J.A. and M. C-R were supported through Juan de la Cierva post-doc grants (grants no. FJCI-2014-21239 and FJCI-2014-20374, respectively) funded by the Spanish Ministry of Economy and Competitiveness.

Although inferring habitat selection and movement in wild fishes using otolith microchemistry has been the subject of much debate, experimental results suggest that complex environmental vs. life history interactions affect the incorporation of certain chemical elements into otoliths. We hypothesized that under relatively homogeneous hydrographic conditions, individual life history trait strategies should dominate signals of geochemical signatures. We tested our hypothesis by analyzing individual chronologies of otolith signals of strontium to calcium (Sr:Ca) and barium to calcium (Ba:Ca) ratios in a sedentary coastal fish (Diplodus annularis). Two areas from the same northwest Mediterranean region with different levels of fishing pressure were sampled: (1) a no-take marine protected area where the “bigger-is-better” strategy should prevail (energy allocation is biased toward growth to compensate for high natural mortality at small sizes) and (2) a highly exploited population where the “smaller-is-better” strategy should dominate (energy allocation is biased toward reproduction to compensate for high fishing mortality at large sizes). Significant differences in reproduction vs. growth trade-offs were observed between the sub-populations. Sr:Ca and Ba:Ca chronologies were compared between back-calculated ontogenetic stages (larvae, juveniles and adults) and sub-populations/life histories using a general linear mixed model. The Sr:Ca chronology successfully reproduced the allocation of energy for growth or reproduction according to the life history strategy of the individual, whereas correlation between ontogeny and otolith microchemistry was less obvious for Ba:Ca. We contend that the direct and/or indirect (e.g., the removal of large predators) effects of fishing pressure on microchemical signals should receive more attention in field studies, as trade-offs between mortality and growth/reproduction might alter microchemical patterns under a given a set of conditions.

In this essay, I review my career in fish and fisheries, describing my work in the context of the ideas of the period and how they have changed with time. My experience may be interesting especially for other women from social backgrounds that do not promote competitive careers. The main lessons that I have learned are that to be persistent and ambitious, to associate with top scientist, and good persons too! is rewarding at several levels. Not to try to be the one in the spotlight but to recognize other people merits gives good results in the long run. Moreover, to take risks from time to time and explore new territories, like science administration in my case, helps to reinvent yourself and keep the intellectual interest alive. I would like to encourage young scientists to persevere, be resilient and take, from time to time, risky decisions. Maybe one does not become rich, but the mental challenges, the networking, the travel and the exceptional places and life experiences make you rich in many worthy ways! One does never get bored.

A widely accepted practice to maximize the survival of mandatory or voluntary released aquatic animals that have ingested hooks is to cut the line, leaving the ingested hook in thousands of fish, sharks, turtles and marine invertebrates worldwide. Recent evidence suggests that the chemical composition (mainly metals) of ingested hooks can potentially be absorbed and retained within soft tissues of fish and can subsequently have adverse effects on their health. In this study, we tested the hypothesis that hard tissues (otoliths) should also show a chemical signal of hooking. Using the mulloway (Argyrosomus japonicus) as a case study, we have compared the microchemistry compositions (Ba, Ca, Co, Cr, Mn, and Sr) of the otoliths measured by Solution Inductively Coupled Plasma Mass Spectrometry (SO-ICPMS) among three groups: control fish (artificially-reared), treatment (deep-hooked) and wild fish. The multivariate Redundancy Analysis fitted to test the general chemical composition of the otoliths among groups revealed a significant chemical signature of hooking characterized by an increase in Sr and Co, and in a smaller effect Ca. Moreover, we found otolith microchemistry as a useful method to differentiate between artificially-reared and wild mulloway. Positive results across other taxa and different recreational and commercial fisheries should show the real magnitude of the chemical signals of hook ingestion, its utilization as a biological tag and its consequences for the health of released individuals.

Stock management should be guided by assessment models that, among others, need to be fed by reliable data of catch and effort. However, precise data are difficult to obtain in heterogeneous fisheries. Specifically, small-scale, multi-gear, multispecies fisheries are dynamic systems where fishers may lively change fishing strategy (i.e., métier) conditioned by multiple drivers. Provided that some stocks can be shared by several métiers, a precise categorization of métiers should be the first step toward métier-specific estimates of catch and effort, which in turn would allow a better understanding of the system dynamics. Here we propose an approach for predicting the métier of any given fishing trip from its landing records. This approach combines the knowledge of expert fishers with the existing sales register of landings in Mallorca (Western Mediterranean). It successfully predicts métiers for all the 162,815 small-scale fishery fishing trips from Mallorca between 2004 and 2015. The largest effort is invested in the métiers Cuttlefish/Fish and Spiny lobster, landings peak for Cuttlefish/Fish and Dolphinfish and revenues for Spiny lobster and Dolphinfish. Métier predictions also allowed us to describe the temporal (seasonal and between-year) trends experienced by each métier and to characterize the species (commercial categories) that are specific to each métier. Seasonal variability is by far more relevant than between-year variability, which confirms that at least some fishers are adopting a rotation cycle of métiers along the year. Effort (fishing trips), landings and gross revenues decreased in the last 12 years (2004–2015). The approach proposed is also applicable to any other fishery for which the métier for a fishing trip sample is known (e.g., on-board observers or logbooks), but relying on fishers expertise points more directly to fishers’ intention. Thus, métier predictions produced with the proposed approach are closer to the actual uses of fishers, providing better grounds for an improved management., This work has received funding from the European Union’s Horizon 2020 Research and Innovation program under Grant Agreements 634495 (MINOUW) and 678193 (CERES).

An amalgam of empirical data from laboratory and field studies is needed to build robust, theoretical models of climate impacts that can provide science-based advice for sustainable management of fish and shellfish resources. Using a semi-systematic literature review, Gap Analysis and multilevel meta-analysis, we assessed the status of empirical knowledge on the direct effects of climate change on 37 high-value species targeted by European fisheries and aquaculture sectors operating in marine and freshwater regions. Knowledge on potential climate change-related drivers (single or combined) on several responses (vital rates) across four categories (exploitation sector, region, life stage, species), was considerably unbalanced as well as biased, including a low number of studies (a) examining the interaction of abiotic factors, (b) offering opportunities to assess local adaptation, (c) targeting lower-value species. The meta-analysis revealed that projected warming would increase mean growth rates in fish and mollusks and significantly elevate metabolic rates in fish. Decreased levels of dissolved oxygen depressed rates of growth and metabolism across coherent species groups (e.g., small pelagics, etc.) while expected declines in pH reduced growth in most species groups and increased mortality in bivalves. The meta-analytical results were influenced by the study design and moderators (e.g., life stage, season). Although meta-analytic tools have become increasingly popular, when performed on the limited available data, these analyses cannot grasp relevant population effects, even in species with a long history of study. We recommend actions to overcome these shortcomings and improve mechanistic (cause-and-effect) projections of climate impacts on fish and shellfish., Sí

The phenotypical variability in otolith shape of anchoveta (Engraulis ringens) was analysed in three zones (I, II and III) from north to south along the Chilean coast, using juvenile and adult fish. Generalised additive models were used to analyse shape indices and canonical discriminant analysis was used to analyse elliptical Fourier harmonics. The form factor and ellipticity indices varied significantly among the three zones, whereas roundness, circularity and rectangularity indices only showed differences between Zones I and III. Fourier reconstructed outlines for five ontogenetic stages suggested important differences among sampling zones, which were larger for sampling Zone III, where, at the same fish length, otoliths were smaller than those sampled in Zones I and II, at least at the pre-recruit stage. Elliptical Fourier descriptors showed significant differences among the three units, with a total percentage of correct classifications for juveniles of 89 and 74% for raw data and cross-validated cases respectively, compared with >85 and ∼65% respectively for adult fish. The results support the hypothesis that juveniles and adults of anchoveta have remained segregated throughout their entire, or at least a fraction of, their life cycle, mainly between the extreme northward and southward zones., The sampling for this study was performed as part of the hydroacousti recruitment survey of anchoveta and the Spawning Monitoring Project, funded by the Chilean Ministry of Economy, Promotion and Tourism (Asesoría Integral en Pesca y Acuicultura, ASIPA, grants 2015 and 2016). Morphological analyses were funded by the Chilean Fund for Fisheries and Aquaculture Research (Fondo de Investigación Pesquera y Acuícola, FIPA, grant 2015–22).

Escape incidents of farmed fish involve economic losses to fish farms, interactions with local fisheries and environmental impacts to coastal ecosystems. In order to ensure a sustainable aquaculture activity it is advisable to gather any kind of information about the escapees for further management strategies. In this study, we aimed to trace the life history of escaped meagre (Argyrosomus regius) through otoliths microchemistry, based on the assumption that escaped fish experience different environmental conditions once they are outside the net-pen compared to their farmed conspecifics. Strontium (Sr88) and barium (Ba138) composition was analyzed using laser-ablation ICP-MS along core-to-edge transects of right sagittal otoliths on escaped and farmed meagre from the same coastal area in the W-Mediterranean Sea. Overall, results showed similar patterns of Sr concentrations throughout the otolith transects between farmed and escaped meagre, although some differences can be observed at specific periods of fish life for Ba concentrations. Consequently, temporal variations regarding otolith Sr:Ba ratios differed between farmed and escaped meagre, suggesting that farmed and escaped fish shared the same origin (rearing at coastal farms) but inhabited in different conditions from a certain time of their life. However, core-to-edge Sr:Ba values also differed among escaped individuals, which might indicate that each individual escaped in different periods. Consequently, the otolith Sr:Ba ratio seemed to be a good indicator of differences between fish groups, showing different temporal patterns. Nevertheless, the limitation of the low number of sampled individuals prevented to draw clearer conclusions. Further research is necessary in order to investigate the potential use of otolith microchemistry as a practical tool to trace of escaped fish, and consequently, to help solving potential conflicts among coastal users improving management of potential negative socioeconomic and ecological impacts., This work was partially supported by the “Adapting to the wild: assessing meagre otoliths escaped from culture cages and evaluation of possible risks in Mediterranean ecosystems” funded by the Department of Education, Culture and Sport of the Valencian Community, Spain (GV/2015/107). SPM's salary was cofunded by the DGPUR of the Balearic Government and CSIC. This study received Portuguese national funds from FCT - Foundation for Science and Technology through project UIDB/04326/2020.

Este artículo contiene 19 páginas, 7 tablas, 4 figuras., Marine recreational fishing (MRF) is a high-participation activity with large economic value and social benefits globally, and it impacts on some fish stocks. Although reporting MRF catches is a European Union legislative requirement, estimates are only available for some countries. Here, data on numbers of fishers, participation rates, days fished, expenditures, and catches of two widely targeted species were synthesized to provide European estimates of MRF and placed in the global context. Uncertainty assessment was not possible due to incomplete knowledge of error distributions; instead, a semi-quantitative bias assessment was made. There were an estimated 8.7 million European recreational sea fishers corresponding to a participation rate of 1.6%. An estimated 77.6 million days were fished, and expenditure was €5.9 billion annually. There were higher participation, numbers of fishers, days fished and expenditure in the Atlantic than the Mediterranean, but the Mediterranean estimates were generally less robust. Comparisons with other regions showed that European MRF participation rates and expenditure were in the mid-range, with higher participation in Oceania and the United States, higher expenditure in the United States, and lower participation and expenditure in South America and Africa. For both northern European sea bass (Dicentrarchus labrax, Moronidae) and western Baltic cod (Gadus morhua, Gadidae) stocks, MRF represented 27% of the total removals. This study highlights the importance of MRF and the need for bespoke, regular and statistically sound data collection to underpin European fisheries management. Solutions are proposed for future MRF data collection in Europe and other regions to support sustainable fisheries management., Institut Français de Recherche pour l’Exploitation de la Mer; French Ministry of Fisheries Management; Greek National Data Collection Programme; European Commission, Data Collection Framework; Department for Environment, Food and Rural Affairs, Grant/Award Number: MF1221, MF1230 and MI001; Norges Forskningsråd, Grant/Award Number: A framework for science-based management of marine recreational fisheries in Norway (267808); State Department of Agriculture, Food Security and Fisheries Mecklenburg- Western Pomerania; Interreg IVa 2 Seas, Grant/Award Number: GIFS project; Dutch Ministry of Economic Affairs, Grant/Award Number: WOT (Wettelijke Onderzoekstaken) programme; European Fishery Fund - Axis 4, approved by FLAG; Department of Environment, Planning, Agriculture and Fisheries from the Basque Government; Government of Galicia, Grant/Award Number: RECREGES project (ED481B2014/034-0)

The cuttlefish (Sepia officinalis) trammel net fishery is one of the most important small-scale fisheries in the Mediterranean Sea. Here we describe the main catch, by-catch and discard patterns found in this fishery on Mallorca Island by onboard surveys of 1005 netting walls from 23 fishing trips. The number of items captured, their size and their subsequent use, i.e. kept for sale or discarded, were recorded. Furthermore, the immediate survival of the unwanted items (i.e. vitality state when the gear came on board) and the medium-term survival of a subsample were assessed. The cuttlefish was the dominant species in the commercial fraction of the catch, particularly during the fishing season peak (March). However, S. officinalis catches quickly decreased further into the season, with other high-value fish, such as Scorpaena scrofa, increasing in the commercial fraction of the catch. As species composition is continuously changing, it is often difficult to determine the main target species of this fishery. This strategy possibly complicates management but maximizes fishing revenue, which was an average of €175 per trip. With respect to discards, up to 104 different species were caught but not commercialized. The most abundant were Holothuria sp. and Torpedo marmorata. Their immediate survival was 100% and 20%, respectively. In both cases, the medium-term survival and the vitality status were high after seven days in monitored captivity. Therefore, in these cases, their immediate release to the sea should be promoted, given that they are exempt from the EU landing obligation. Interviews with fishers revealed that the perceived quantity of discards was lower than the amount recorded by the present study. Currently, just a small percentage (1.5%) of these discards will be affected by the landing obligation enforced by the new European discards ban., This study is a result of the Associated Unit LIMIA-IMEDEA. It received funding from the European Commission’s Horizon 2020 Research and Innovation Programme under Grant Agreement No. 634495 for the Science, Technology, and Society Initiative to Minimize Unwanted Catches in European Fisheries (MINOUW). G. Catanese was supported by a postdoctoral research contract from INIA-CCAA. H. Hinz was supported by a Ramón y Cajal Fellowship (grant funded by the Ministerio de Economía y Competitividad de España and the Conselleria d’Educació, Cultura i Universitats de la Comunidad Autónoma de las Islas Baleares).

CentroOceanogra´fico de Gijo´n, Avda. Pri´ncipe de Asturias, 70 Bis, 33212 Gijo´n, Asturias, Spain*Corresponding author: tel: +34 971610829; e-mail: cdiaz@imedea.uib-csic.esDi´az-Gil,C.,Palmer,M.,Catala´n,I.A.,Alo´s,J.,Fuiman,L.A.,Garci´a,E.,Gil,Mari´adelMar,Grau,A.,Kang,A.,Maneja,R.H.,Mohan,J.A., Morro, B., Schaffler, J. J., Buttay, L., Riera-Batle,I., Tolosa,B.,and Morales-Nin, B. Otolith fluctuating asymmetry: a misconceptionof its biological relevance? – ICES Journal of Marine Science, doi: 10.1093/icesjms/fsv067.Received12 November 2014; revised 23 March 2015; accepted 28 March2015.For decades, disruption of the bilateral symmetry of body structures has been related to underperformance and, hence, to fitness. In fish, thisconceptcoupledwiththeclaimedevidenceforincreasedfluctuatingasymmetry(FA)ofpairsofhardstructures,suchasotolithsunderconditionsofstress,hasledtotheuseofotolithFA(OFA)asaproxyforindividualfitnessandpopulationsuccess.InterpretingthosesignificantdifferencesinOFAinrelationtostress-inducingenvironmentsandusingthemtoidentifysuboptimalconditionsforsurvivalisespeciallyappealinginthecontextof,forexample,assessingclimatechangeusinghistoricalotolithcollections.DespiteseveralworksthatgiveevidencetosupporttheusefulnessofOFAapproach,wereportonanumberofunpublishedandpublisheddatasetsfromawiderangeofboth,wildpopulationsandexperimentaldesignsthatshownocorrelationbetweenOFAandanyoftheusualindicatorsoffitnessorbetweenOFAandexpectedstressgradients.Ourresultssuggestthattheremaybeastrongbiasinthepublishedliteraturetowardspositiverelationships,despitetheenormousimportanceofnegativeresultsforunderstanding the significance of OFA. These results might shed light on the interpretabilityof OFAin both laboratory and field studies.Keywords: fitness, fluctuating asymmetry,negative results, otolith.

An economically important, small-scale fishery operates during the winter months in Mallorca. Using a special surrounding net that is hauled over the sand and gravel bottoms of bays at depths reaching 30 m, it primarily targets Aphia minuta and Pseudaphya ferreri, but other goby species and juveniles of the Pagellus spp are also caught. Similar fisheries are operated on the Spanish coast and in Italy. This fishery is run with specific licenses, equipment controls, and closed seasons (based on species availability). In cooperation with local fishermen, the administration has in recent years established a daily quota for sustaining the sales prices 22of the species caught. A management plan was set up in 2013 in accordance with European Union rules to ensure the sustainability of the fishery. Its sustainable quotas have been set at 30 kg/day/boat for A. minuta and 50 kg/day/boat for P. ferreri, and the by-catch cannot exceed 10% of the total catch. Landings are permitted in 11 fixed ports and only 35 boats can fish with the regulated nets from December 15 to April 30. A co-management committee was created with the participation of the public administration, fishermen’s associations, researchers, and certain non-governmental organizations. The co-management process was revised and fishermen’s opinions were obtained in a successful enquiry that was answered by the majority of the operating fleet, and their views on the management rules will be considered in future regulations. The co-management of the small-scale boat seine fishery in the Balearic Islands is thus an ongoing collaborative and communicative process in a local community that continues to evolve over time. Although the fishermen are represented by their port guilds, communication efforts are necessary in the near future to ensure the success of the co-management process., This research was supported by the H2020 REA 634495-MINOUW Project

Although some stocks are being severely exploited by recreational fishing, estimating the biomass extracted (harvest, H) by recreational fisheries is difficult, especially for marine recreational fisheries. One way to estimate H by recreational fisheries is to combine the fishing effort (E) with catch-per-unit-of-effort (CPUE) data. However, naively ignoring heterogeneity in E and CPUE may result in biased and imprecise estimates of H. We propose a framework to address three relevant heterogeneity levels: the spatial and temporal heterogeneity of recreational E, environmental effects on recreational CPUE, and the variability in angler skills (between-angler heterogeneity). Specifically, we combine (i) space-time model predictions of E (number of boats per km2) on the day scale (i.e., fishing trips), (ii) environmentally driven model predictions of daily catch (number of squid per fishing trip), and (iii) off- and on-site sur-veys to account for angler heterogeneity. The precision of the H estimates was assessed using bootstrap confidence intervals. This framework was applied to the recreational fishery for the squid Loligo vulgaris at Palma Bay (Mallorca Island, western Mediterranean). The estimated effort was 15,750 angler-fishing trips (95% CI: 13,086 to 18,569), which yielded an annual harvest of 20.6 tons (95% CI: 16.9–24.5). This harvest was estimated to represent 34% of the total commercial landings in Mallorca, which highlights the importance of recreational harvesting and the need to account for recreational fisheries to improve squid stock management. The framework proposed here provides a promising tool for estimating H in other heterogeneous recreational fisheries and may be the first step toward assessing the actual impact of recreational fisheries on squid populations, SI

Sustainable management of exploited stocks demands, among others issues, to identify the spawning spatio-temporal patterns and eventually to protect the spawning grounds of the target species. Squid seems to aggregate at this crucial period of the life-history, which implies increasing vulnerability to fishing. Unlike those of other loliginid species, the spawning preferences of the European squid are largely unknown because finding egg clutches of this species in the wild is challenging. Validated records from research programs are virtually inexistent but unsystematic records from, for example fisherman, suggest that squid spawns regularly on artificial structures. Here, we report for first time a description of the spatio-temporal pattern of squid spawning on artificial devices (ADs). Thirty ADs were deployed over one year at a marine reserve (Cabrera National Park). ADs were distributed covering the three main types of benthic habitat, and ranging from 5 to 50 m depth. ADs were sampled monthly. Three main patters have been evidenced: (i) squid would prefer sandy bottoms for spawning, (ii) spawning would peak in spring, and (iii) squid would expand their spawning areas to shallower waters during the coldest months. It is debatable to extrapolate these patterns to those actually takes place in natural conditions. However, given the heavy fishing effort exerted on squid and data scarcity, the precautionary approach supports to take data from ADs as a starting point for advising sustainable management. Assuming that spawning at ADs and at the wild are correlated, the first pattern may be related to the faster marine currents that prevail on sandy bottoms or the smaller abundance of potential predators in these habitats. The second pattern may be related with the typical phytoplankton–zooplankton cascade that, in the Western Mediterranean, takes place just preceding spring. While the third pattern is in accordance with the hypothesis that squid may undergo a spawning migration.

Four visual censuses targeting Octopus vulgaris living in dens on sandy bottoms were carried out from June to October 2013 in the National Park of the Atlantic Galician Islands (NW Spain). Censuses were undertaken by scuba diving between 5 and 21 m depth in daytime. The total area swept was 13.75 ha. There were no significant differences between octopus presence in dens during open and closed fishing seasons. Depth had a significant negative relationship with occupancy. The average number of dens per 1000 m 2 was 3.84±0.84 in June and 3.89 in October. The area per den was 260 m 2 . Den number estimations varied between 1586 and 2057. The largest number of dens (76.5%) was found between 5 and 10 m depth. Den distribution was clumped. No significant differences were found between octopus size classes (small, medium and large) and den diameter. Associate dens were observed. There were no significant differences in den diameter and shell types found around the middens. Many dens could be “permanent”. Drilling bivalve shell behaviour is discussed. The surveyed area had around 1100 individuals, mainly small specimens. No significant differences were found between octopus size and depth. Substrate, den type and food abundance and availability (especially razors Ensis arcuatus ) seem to be the main factors influencing dens and octopus density and distribution. Den availability does not appear to be a limiting factor in this case. Temperature, den availability, predators and fishing pressure influencing density and distribution are discussed. Rodas inlet may be a preferential habitat for O. vulgaris individuals ranging from 200 to 2000 g, but especially small specimens ( ≤ 1000 g).

When gene flow is limited and harvesting is intensive, fishing may alter life histories and favour trait combinations that collectively reduce adult body size. However, empirical evidence of downsizing of adults in small-bodied coastal fish is still scarce, in part due to the lack of knowledge about the selective nature of certain fishing gears, such as recreational angling, and the difficulties in estimating the dispersion of pelagic early-life stages. Using the small-bodied sedentary coastal marine fish Serranus scriba as a model, we first empirically show that recreational angling selects for life-history traits (i.e. increased reproductive investment) that promote downsizing of adults. Second, using Lagrangian particle dispersion modelling, we show how local hydrodynamics generates patterns of limited connectivity and the emergence of meta-population structure. Finally, the life histories presently observed in isolated populations of S. scriba that experienced differential fishing pressure matched expectations of fishing-induced downsizing of adult body size. Body size is an important trait in aquatic food webs, and evolutionary downsizing might have unforeseen consequences. From a precautionary perspective, maintaining the metapopulation structure and the full range of genotypes inherent in them is important, even for smallbodied, geographically restricted fish species that are mainly harvested by recreational anglers. © Inter-Research 2014., The present study was partially financed by the research project CONFLICT (grant no. CGL2008-00958) and REC2 (grant no. CTM2011-23835), both funded by the Spanish Ministry of Economy and Competiveness (MINECO). J.A. was supported by an FPI fellowship (MINECO), and A.J. was supported by a Ramón y Cajal grant (MIMECO). We also thank the people of the National Park of Cabrera (sampling was performed within the framework of the research project ROQUER grant no.CTM2005-00283). R.A. received funding from the German Federal Ministry for Education and Research (BMBF) through the Program for Social-Ecological Research for the project Besatzfisch (grant no. 01UU0907). The finalization of the study was made possible by the BTypes project funded through the Leibniz Competition (SAW-2013-IGB-2) to R.A. and a Marie Curie Post Doc grant to J.A. (FP7-PEOPLE-2012-IEF, grant no. 327160)

The biology, ecology, and dynamics of the deep-sea teleost black scabbardfish in the northeast Atlantic are reviewed. The black scabbardfish is a commercial bathypelagic species found in the NE Atlantic mostly from Iceland to the Canary Islands and Western Sahara, at depths from 800 to 1300 m. The spatial structure of its population is still uncertain, although the existence of one single stock that migrates around the NE Atlantic driven by feeding and reproduction is the most likely hypothesis consistent with available data. This review is based on data from commercial fisheries off the Faroe Islands, Hatton Bank, the west of the British Isles, and Portugal (mainland, Azores, and Madeira) and from Icelandic and Scottish scientific surveys collected between 1988 and 2012. Spawning of black scabbardfish occurs around Madeira and the Canary Archipelagos during the last quarter of the year. According to the migratory hypothesis, eggs, larvae, and possibly juveniles move north to areas from south of Icelandic and Faroe Islands to the west of the British Isles where they remain for some years to feed and grow. Then, they move south to the area off mainland Portugal, where they reach the size of first maturity but do not reproduce, and later move further south to the spawning grounds. Further studies are needed to understand which of the environmental conditions prevailing around Madeira and the Canaries, but not elsewhere, allow this species to mature and subsequently reproduce. This review suggests that a multidisciplinary approach is required to confirm the spatiotemporal migration and habitats used by black scabbardfish populations in the NE Atlantic at different life stages. Otolith contour shape and microchemistry, fatty acids, carbon and nitrogen stable isotopes, as well as steroid hormones are proposed as promising alternative tools for responding to this challenge. © 2013 EDP Sciences, IFREMER, IRD., This work was supported by the DCF – European Commission Fisheries Data Collection Framework, the EU project Management and monitoring of deep-sea fisheries and stocks (DEEPFISHMAN, Grant No. 227390), the Portuguese project Certificação MSC em Portugal: obtenção de conhecimento e estudos de viabilidade para candidaturas de pescarias costeiras e artesanais (CERTIFICA, PROMAR, 2011-2015), and a doctoral fellowship granted to I. Farias by Fundação para a Ciência e Tecnologia (SFRH/BD/64434/2009)

Cabrera National Park is a Marine Protected Area (MPA) located in the South of Mallorca, Balearic Islands, Spain. It has a valuable ground fishery that includes several species of crustaceans of commercial interest, such as the European spiny lobster Palinurus elephas. Lobster traps, although permitted and even promoted by the park's authorities, have been abandoned due to the higher efficiency and catch per unit effort of the trammel nets. This study evaluates traditional and modern lobster trap designs to determine the most suitable one as an alternative to trammel nets. The gear was first tested in an aquarium and consisted of a reed trap, a plastic trap and a metal trap, all three historically used in Mallorca, and a modern Japanese collapsible trap. By conducting behavioral observations and exposing 40 lobsters to the traps it was found that the collapsible trap captured 20% of the lobster exposed to the trap, while the plastic trap only 10% and the reed and metal trap only 2.5% and 0%, respectively. In addition, experimental trials were conducted in a fishing ground of Cabrera National Park using two 450 m long strings of traps. Each string was composed of 30 collapsible traps or 30 plastic traps, with traps spaced at 15 m intervals along the line. Lobster catches were 24 (0.8 lobster/450 m) in the plastic traps, but only 9 (0.3 lobster/450 m) in the collapsible ones. When considering that the minimum legal size for lobsters is larger than 9 cm carapace length (CL), only 9 lobster (0.3 lobster/450 m) could be landed after deploying 1800 traps, and all of them coming from plastic ones. To compare the effectiveness of traps with lobster trammel nets, 14 fishing operations were carried out with a total of 5950 m of net deployed. Thirty-three lobsters were captured (2.37 lobster/450 m) in the nets, of which only 17 reached commercial size (1.22 lobster/450 m). Although the collapsible trap has caught more lobsters in the aquarium compared to the plastic trap, the plastic trap performed better in the field. This appears to be due to the effects of bycatch species, particularly octopus. Our results stressed the necessity of implementing an evaluation of the lobster population dynamics to design more efficient management measures. The fishers themselves recognize the need to an agreement for changing the paradigm from maximizing catches to maximizing profit., This research was partly funded by La Caixa “Adaptative management of marine populations in the Archipelago of Cabrera National Park due to climate change: reduction of antropic impact produced by fishing” and Costa Cruceros

Department of Biology, University of Bergen, PO Box 7803, N-5020 Bergen, Norway. Institute of Marine Research and Hjort Centre for Marine Ecosystem Dynamics, PO Box 1870, N-5817 Bergen, Norway. Email: audrey.geffen@uib.no Mediterranean Institute for Advanced Studies (IMEDEA), Spanish National Research Council (CSIC)–University of the Balearic Islands (UIB), Miquel Marques 21, E-07190 Esporles, Islas Baleares, Spain. Email: beatriz@imedea.uib-csic.es Southern Seas Ecology Laboratories, Darling Building, School of Biological Sciences and Environment Institute, University of Adelaide, SA 5005, Australia. Email: bronwyn.gillanders@adelaide.edu.au

11 páginas, 1 figura, 1 tabla, Coastal, small-scale fisheries (SSF), whether artisanal (professional) or recreational, represent important socioeconomic activities across Europe that are currently undergoing a number of changes. This paper reviews and analyses the drivers of these changes, and makes recommendations for the future management of SSF. From the biological standpoint, the use of fishing gears that actively select certain species, sizes and sexes, the deployment of fishing gears on certain fragile habitats, the loss of fishing gears and the use of non-native species as bait are examples of how SSFs can threaten the sustainability of vulnerable coastal species and habitats. From a socioeconomic perspective, several factors are altering the traditional characteristics of coastal SSF. Among the most important is the growth of recreational fisheries in coastal waters and the disappearance of traditional low technology fisheries or their substitution by more mechanised, technical fisheries, which is leading to a loss of the traditional ecological knowledge held by artisanal fishers. On the other hand, the increasing competition between artisanal and recreational fisheries, and between them and commercial fishing operations, are also altering the classical features of coastal fisheries in some European countries. SSFs must adapt to the requirements of the new Common Fisheries Policy (CFP), namely management based on Maximum Sustainable Yield (MSY), multi-annual management plans and ecosystem based principles. It is concluded that it is necessary to integrate different assessment approaches (biological, social and economic), with active participation from stakeholders, governments and relevant research institutions, to better evaluate and manage coastal fisheries., The workshop was funded by the European Science Foundation (ESF). Cowx was supported under EU funded CERES project nr. 678193 for drafting the manuscript.

4 pages, 2 figures, 1 table, [EN] Otolith marking provides a reference point for otolith growth patterns by validating the temporal significance of growth increments. This widespread method is primarily implemented using fluorescent dyes. The incorporation of a trace element that appears naturally in otoliths offers an alternative approach. Diplodus annularis and Serranus scriba otoliths were marked with an intramuscular injection of SrCl2 diluted in 0.9% sterile saline solution (55 mg Sr ml-1 saline solution), given at a dose of 100 mg Sr kg-1 fish. At 277 to 366 days after marking, the fishes showed little or no mortality and experienced growth in length and weight. All of the otoliths analyzed showed a clear Sr mark detected with backscattered or secondary electron imaging during a scanning electron microsope (SEM) analysis. The mark was confirmed by Sr analysis using an X-ray detector and an energy dispersive spectrometer system with the SEM. The otoliths continued to grow after the mark, and background Sr values in this new growth were much lower than at the mark. This method was feasible and yielded good results. However, the method’s cost may limit its applicability to experimental studies, [ES] El marcado de los otolitos permite establecer una referencia que valida el significado temporal de los incrementos de crecimiento. Este método muy extendido en estudios de validación utiliza preferentemente agentes fluorescentes. Un método alternativo puede ser el marcado con un elemento que aparece de forma natural en la composición de los otolitos. Los otolitos de Diplodus annularis y Serranus scriba se marcaron mediante una inyección intramuscular de SrCl2 diluída en solución salina estéril al 0.9% (55 mg Sr ml-1 solución salina) a una dosis de 100 mg Sr kg-1 individuo. Los individuos mostraron crecimiento en peso y talla y muy baja mortalidad después de 277 a 366 días tras el marcado. Todos los otolitos analizados con SEM mostraron una marca nítida, detectada tanto con los electrones retrodisperados como con los electrones secundarios. Mediante microanálisis de rayos X con un sistema EDS acoplado al SEM, dicha marca fue identificada como Sr. Los otolitos continuaron su crecimiento tras el marcado con una baja concentración de Sr comparada con la presente en la marca. La aplicabilidad del método se discute considerándose que ofrece buenos resultados. Sin embargo, el relativo coste del mismo limita su aplicabilidad en estudios experimentales, This is a contribution of the MICINN-funded project CGL2008-00958

We used acoustic telemetry to describe the spatial and temporal patterns of habitat use of one of the species most targeted by recreational anglers in the NW Mediterranean, Serranus cabrilla (Linnaeus, 1758). Temporal patterns and fish position were determined using a fixed-receiver array located in a marine protected area (MPA) in Palma Bay (Balearic Islands). Fish position as centre of activity (COA, the centre of the area the fish uses during a specific time) and space utilisation preferences could be described due to a receiver array design with a high range detection overlap (more densely distributed near the COA). There were significantly more detections per time unit during the day, which was interpreted as increased activity possibly related to feeding habits and social behaviour. S. cabrilla spent 95% of its time in an average area of 0.77 ± 0.17 km2, with a core area (50% of the time) of 0.10 ± 0.29 km2. The home range size was not related to fish size or diel pattern (i.e. the size of the daytime home range was not significantly different from the night range). The linearity index and the index of reuse (proxies of site fidelity) also demonstrated that this species has high site fidelity, which suggests that it is sedentary with a limited adult dispersal capacity. Two main habitats were observed in the study area, and S. cabrilla spent on average much less time in seagrass meadows (Posidonia oceanica beds) compared to soft, gravel and detritus bottoms. A relatively small MPA would be a useful management tool for establishing sustainable exploitation levels of this species. © Inter-Research 2011., This study was financed by the research project CONFLICT (CGL2008- 00958) funded by the Spanish Ministry of Science and Innovation

A quantitative ecomorphological study was carried out on the sagitta otoliths of Antarctic and Subantarctic nototheniids, a particularly interesting family due to its fast adaptive radiation into different life strategies. We analyzed the otolith shape and size of 18 nototheniids to test the relationship between phylogeny, otolith characters and trophic niche. Relative size (area, length, width, perimeter and weight) and shape (biometric warp analysis based on homologous and pseudo-homologous landmarks) measurements were compared with phylogenic, habitat dwelling and food composition analyses. The results of the multivariate analysis of these factors indicate that there is a weak relationship between otolith shape of nototheniids and phylogeny; however, there is a clear correspondence between relative otolith size and shape and their trophic niche. The most benthic feeders of the family had the largest sagittae in relation to body size, and pelagic species had smaller and rounder shaped sagittae than benthic species. Consequently, in ecomorphological studies, it is useful to analyze the size and shape of sagittae. The discoidal shape of pelagic species, such as Pleuragrama antracticum, can be considered as a paedomorphic characteristic, converging to the juvenile sagittae of many species, which exhibit round sagittae that become elongated as they grow., This work was undertaken as part of the SCAR EASIZ program, and was supported by the Alfred Wegener Institute and the Spanish Antarctic Program (ANT1995-1249-E, ANT1997-1884-E, REN2000-1783-E).

Fluctuating asymmetry (FA), defined as random deviations from ideal, perfect symmetry, has been hypothesized to be negatively associated with fitness and positively associated with stress. Fish otoliths deserve special attention in regard to this topic because their FA is relatively easy to measure, unlike the fitness of wild fish themselves. In addition, otoliths are convenient for estimating FA, because they are systematically extracted for aging purposes, and otolith collections might allow the use of FA as a bioindicator of change at different spatio-temporal scales. Here we demonstrate 2 key methodological tools: The use of shape instead of previously used univariate (metric or meristic) traits, and the use of a statistical protocol capable of disentangling true FA from other types of asymmetry (namely, directional asymmetry and antisymmetry) and from measurement error. In the case of the razor fish Xyrichthys novacula; fluctuation asymmetry of the otolith shape of 180 individuals from 5 populations accounted for 23.2% total shape variability (5 fold larger than the measurement error). Moreover, FA clearly differed between populations. In contrast, FA measured using a univariate trait (radius at the sulcus) did not detect between-population differences. Moreover, in a simulation experiment, we demonstrate that FA measured using shape is able to reveal a true pattern, while FA measured using a univariate trait extracted from the same data is unable to do so. Therefore, the analysis of FA using shape paired with an adequate statistical model may increase our knowledge of the potential links between otolith FA and fitness or stress. © 2010 Inter-Research.

Though whole otoliths are commonly adopted in age assignment of black scabbardfish, this study showed that sectioned otoliths are more appropriate because growth increments are more evident and ageing of larger specimens is easier. Vertebrae are not the most appropriate structure for ageing but, in the absence of otoliths, this structure may be useful in age assignment of this species. To verify possible differences between age and growth among specimens from the southern NE Atlantic, 1075 sectioned otoliths from specimens from mainland Portugal, 436 from Madeira and 107 from the Azores were analysed and the distribution of length-at-age obtained for each sex and region was determined. Significant differences were obtained in the comparison of the distribution of length-at-age between Madeira, the mainland and the Azores. The von Bertalanffy growth model was applied to back-calculated mean length-at-age data from Madeira (Lt = 1586 [1 – e –0.119(t+2.282) ] females; Lt = 1461 [1 – e –0.146(t+1.441) ] males) and mainland (Lt = 1354 [1 – e –0.170(t+2.040) ] females; Lt = 1240 [1 – e –0.208(t+1.654) ] males), and significant differences in the growth equations were obtained. Furthermore, a regression tree model was used to investigate how growth is conditioned by reproduction. The results showed a clear separation between individuals from the two areas, both females and males from the mainland (non-reproductive individuals) being characterised by a lower gonadosomatic index and a lower age.

Alós, J., Palmer, M., Balle, S., Grau, A. M., and Morales-Nin, B. 2010. Individual growth pattern and variability in Serranus scriba: a Bayesian analysis. – ICES Journal of Marine Science, 67: 502–512. Variability in growth patterns at an individual level in Serranus scriba is described using a Bayesian approach for a generalized von Bertalanffy growth model that accommodates one change in growth rate at a specific point during the lifespan. The approach enables individual growth curves to be inferred, even in a species with a relatively short lifespan and no commercial value, i.e. limited sample sizes available, but potentially endangered by recreational fishing. The change in growth rate may be the result of differing allocation of energy between reproductive and somatic activities at different ages. Overall, the approach presented provides adequate input for future implementation of population dynamics models that take into account individual variability, e.g. individual-based models, even for species for which limited data are available.

Short-term temporal variability in deep-sea demersal fish assemblages is described for two slope areas characterised by different oceanographic conditions, which are situated north (Balearic sub-basin, BsB) and south (Algerian sub-basin, AsB) of the Balearic Islands (western Mediterranean). A total of 75 hauls were analysed from six bottom trawl surveys carried out in the two sub-basins. At BsB, surveys were designed for sampling different slope habitats during April 1991, December 1991, March 1992 and July 1992: (i) a submarine canyon at a depth of around 450 m, (ii) the upper slope at a depth of 600-650 m, and (iii) the middle slope at a depth of around 1200 m. At AsB, surveys were carried out during October 1996 and May 1998, along a continuous transect on the upper, middle and lower slope. The taxonomic composition, ecological parameters (number of species, abundance and biomass) and biomass spectra of the assemblages, as well as the length frequency distribution of the main species, were compared for different seasons and bathymetric ranges. Forty-four demersal species were captured in BsB and 38 in AsB. Helicolenus dactylopterus and Trachyrinchus scabrus were more abundant in BsB, and Hoplostethus mediterraneus, Galeus melastomus and Centroscymnus coelolepis in AsB. Depth was the determinant factor in all the analyses. Species-specific densities (abundance and biomass) showed significant differences between surveys, depth strata and their interaction in BsB. However, survey and its interaction with depth, were not significant in AsB. We also found significant differences in relation to depth and season for the three ecological parameters tested in BsB, but only significant differences in relation to depth in AsB. Biomass spectra showed large differences in relation to depth but only slight between-survey differences, which mainly occurred in the upper slope. The length frequency distributions of single species presented short-term temporal variations, mainly due to the varying presence of a larger proportion of small or large individuals. Depth, geographic area and sampling time were the main factors determining the species composition and structure of deep-sea slope demersal fish assemblages. The effects of short-term temporal variations were observed in both the replacement and the size structure of some dominant and subdominant species throughout the year. The different temporal variation effects observed between the two sub-basins might be related to differences in productivity and its transport to the benthos. © 2008 Elsevier Ltd. All rights reserved.

9 pages., Juvenile turbot Scophthalmus maximus were kept in captivity and were fed a prepared food contaminated with 5 levels of seawater-accommodated fuel oil, from 2.4 ± 0.35 to 48.2 ± 2.2 mg/g food. Oil that had been recovered from that released by the tanker 'Prestige' was used. Fish (n = 202) were individually tagged while length and weight were recorded. They were then placed randomly in 6 different tanks (1 control and 5 treatments, 32 to 35 individuals in each. For 6 wk, they were fed 3 times daily. At the end of the experiment, the fish were sacrificed, and length and weight recorded. At the beginning of the experiment, there were no significant differences in fish size and weight among tanks. After the treatment, greater oil concentration significantly reduced growth rate in size and weight. However, probably due to competition, smaller fish did not demonstrate notable growth during the experiment in any tank, while larger fish grew more in the tanks with lower oil concentrations in the food. Increasing oil concentration also reduced food consumption by individual fish. However, the reduced feeding rate alone did not explain the reduced growth rate, which was probably also the result of a major reduction in the ability for food energy conversion.

These are the first data on the feeding of larval albacore (Thunnus alalunga Bonnaterre, 1788) in the Mediterranean. Specimens were gathered from day-time bongo-hauls conducted over the SW Mallorcan (Balearic Islands) shelf-slope. Ninety eight percent of 101 individuals ranging from 2.65 to 9.4 mm standard length (SL) contained 1 to 15 prey items per gut. Mean number of prey/gut was 3.55 ± 2.19 (SD). A positive correlation was found between larval SL and the number of prey/gut. The analysis of frequency of occurrence (F), numerical frequency (N), weight frequency (W) and the Index of Relative Importance (IRI) showed a dominance of copepodites and nauplii in the smallest size-class. As larvae grew, cladocerans and Calanoida copepodites dominated the diet, and cladocerans and copepodites were important in F, N and W. Piscivory was observed after notochord flexion and was important in terms of W. A positive correlation between mean prey size and both SL and lower jaw length (LJL) was observed. The niche breadth (S) did not vary with LJL, but the raw prey size range did. Larger copepodites, the absence of nauplii and the incorporation of fish larvae and a larger number of cladocerans in the diet accounted for the increase in mean prey size through increased larval size.

The implementation of ecosystem-based approaches to marine management points to several shared objectives between conservation and fisheries management that require: better knowledge of the life history of the exploited resources; to elucidate the information encoded into the calcified tissues (otoliths, scales, bones, shells and corals) of marine and freshwater organisms; to support knowledge-based sustainable ocean management and use. IOS2014 was the 5th in a series of independent symposia which have been convened, beginning in 1993, to encourage the exchange of information and expertise and promote the development of new techniques and applications for otolith-based analysis in ecology, management, and conservation. The aim of the Symposium was to explore the use of calcified tissues as tools to support management and define indicators at environmental, community, population and individual levels. Despite the economic difficulties worldwide, a total of 329 registrants from 45 countries attended the Symposium. The symposium was organized around four themes: Environmental indicators, Community indicators, Population indicators, and Individual indicators. One day was devoted to workshops; on Otolith Shape Analysis and on Age Validation. The traditional approach of using calcified tissues to determine fish age and therefore to determine the fish population structure has been augmented by new applications to address questions of population connectivity, migrations, and trophic ecology. These tools have become increasingly important as we transition to spatially explicit and ecosystem-level management tools. They are now extended to applications related to spatial use (essential habitats) and to the use of otoliths as a record of past and present environmental conditions. Otoliths are valuable as individual bio-recorders, and – as demonstrated in the variety of presentations at the symposium – also as indicators for higher levels of organisation. The increased appreciation for otolith archives was also apparent; taking advantage of the extended otolith sampling for stock assessment and providing ample collections from different species, as well as from the fossil records.

5 pages, 3 tables, Both resident and non-resident anglers (tourists) practice recreational fishing in Majorca (Balearic Islands, western Mediterranean). We present the results of two surveys designed with the objective of estimating the expenses incurred by anglers in recreational fishing and describing their motivation for fishing. A mail survey targeted resident anglers, and two intercept surveys targeted tourist anglers (in the mass tourism and nautical tourism sectors). The main motivation for resident anglers was enjoying tranquility, followed by catch consumption. For tourists, fishing was not the motivation for visiting Majorca. The expenditure of resident recreational anglers is estimated to be 57 million Euro (1% of the Majorcan economy). The number of tourists practicing recreational fishing was low, but their catch was estimated to encompass 16% of the total commercial coastal fishery catch. In addition, the economic value added through fishing expenditure may be 6 million Euro due to the large number of tourists visiting Majorca. The amount of catch in weight by all anglers combined was significant (43% of the catch in weight of commercial coastal fisheries) and should be considered in the management of coastal fisheries in the Balearic Islands and elsewhere in the Mediterranean where recreational fishing is important. © 2014, This work was funded by the Spanish MINECO project CONFLICT (CGL2008-958)

© 2015 Elsevier B.V. The selection of spawning habitat of a population of Octopus vulgaris that is subject to a small-scale exploitation was studied in the Cíes Islands within the National Park of the Atlantic Islands of Galicia (NW Spain). The technique used was visual censuses by scuba diving. We conducted 93 visual censuses from April 2012 to April 2014. The total swept area was 123.69ha. Habitat features (season, depth, zone, bottom temperature, swept area, bottom substrate type, and creels fishing impact) were evaluated as predictors of the presence/absence of spawning dens using GAM models. O. vulgaris has a noteworthy preference for spawning in areas with hard bottom substrate and moderate depth (approximately 20m). The higher density of spawning dens (1.08ha-1) was found in a surveyed area of 50.14ha located in the northeastern part of the northern Cíes Island. We propose to protect the area comprised from Punta Escodelo to Punta Ferreiro between 5 and 30m depth. This area has a surface of 158ha equivalent to 5.98% of the total marine area of the Cíes islands. The strengths and weaknesses of a management strategy based on the protection of the species' spawning habitat are discussed., M. Sestelo's research was supported by grant MTM2011-23204 from the Ministerio de Ciencia e Innovación (España), by grant CN2012/180 from the Galician Regional Authority (Xunta de Galicia), by SFRH/BPD/93928/2013 Grant from Portuguese Fundação Ciência e Tecnologia and by Portuguese Funds through “FCT – Fundação para a Ciência e a Tecnologia” in the form of grant PEst-OE/MAT/UI0013/2014. Project financial support was provided by the Organismo Autónomo de Parques Naturales de España of the Ministerio de Agricultura, Alimentación y Medio Ambiente (CEFAPARQUES, Project number: 458/2011)

Fish otoliths have provided biologists with a treasure-house of valuable life history information across levels of biological organization from individuals to ecosystems. Otoliths have long been used to provide the age and growth estimates which are basic data that underpin scientific fisheries and fisheries ecology. The traditional use of calcified tissues (CS) has been augmented by new applications to address questions of population connectivity, migration, and trophic ecology. These tools have become increasingly important in meeting the demands for spatially explicit and ecosystem-level management tools. Analysis of CS is now extended to applications related to spatial use (essential habitats) and as a record of past and present environmental conditions. This special volume of the ICES Journal of Marine Science contains contributions from the 5th International Otolith Symposium (IOS 2014), an ICES Science Symposium held in October 2014, in Mallorca, Spain. IOS 2014 is a continuation of a series of symposia that started in 1993 to encourage the exchange of information and expertise and to promote the development of new techniques and applications for otolith-based analysis in ecology, management, and conservation. IOS 2014 was the largest meeting to date, with 329 participants from 45 countries. The aim of IOS 2014 was to explore the use of CS as tools to support management and define indicators at environmental, community, population, and individual levels. This international forum is the centre for the exchange of information about developments in the field. New techniques of analysis, statistical treatment, and indeed new areas of application are all presented in this forum. Regular attendees are often the prominent users of otolith analyses in their home institution, and many are active in ICES work. This is also a premier venue for interaction between ICES scientists and those working in other parts of the world. North America, Japan, Taiwan, and Australia are particularly active in advancing otolith techniques, and exchange of ideas and information is crucial to improving the science in the ICES community. © International Council for the Exploration of the Sea 2015. All rights reserved

© 2015 Elsevier Ltd. The aim of the SEAS-ERA initiative (2010-2014), developed within the European Union Framework Programme (EU FPVII) (contract 249552), was to coordinate the structure of national and regional marine and maritime research programs to empower and strengthen marine research all across Europe. A major goal was the development and implementation of common research strategies and programs related to European seas basins. To achieve this goal, SEAS-ERA was applied at two different levels, regional and pan European, to identify common priorities and needs in five areas, namely strategic planning (marine research agendas), joint research activities (common programs and joint calls), marine research infrastructures and human capacity building to reduce imbalances among regions. SEAS-ERA was also strongly committed to enhancing public awareness of marine and maritime scientific and policy issues in Europe., The SEAS-ERA initiative was funded by EU FPVII-contract 249552

Fish assemblages associated with Posidonia oceanica from three locations of the western Mediterranean (Mallorca, Formentera and Alacant, Spain) were sampled in order to assess their spatial variability at three different scales ranging from 100 km. Sampling was carried out using a beam trawl. Simultaneous sampling at these three spatial scales with the appropriate number of replicates implies a huge effort which is rarely possible to achieve. Consequently, we propose an arrangement of data coming from different sampling programs, after testing and making sure the specificities of each program cannot be confounded with the spatial variability. The two preliminary experimental designs adopted in order to combine the datasets were: (1) differences between two consecutive years were tested by sampling the same meadow (Formentera) in June 2001 and June 2002; and (2) differences attributable to the meadow structure were evaluated by sampling two meadows (Mallorca 2000 and Formentera 2001). The absence of any significant correlation pattern for univariate community descriptors and multivariate species-specific densities (i.e. individuals per hour) related to both between-year and within-location structural differences of the meadows, allow us to combine data from the three locations (Formentera 2001, Mallorca 2000 and Alacant 2000) in a single analysis aimed at determining how much variability is explained by the three spatial scales considered. The between-location scale (>100 km) is the most variable scale for species-specific densities (multivariate approach). Spatial variability at the smallest scale (

Helicolenus dactylopterus and Merluccius merluccius are widely distributed on the continental slopes of the Atlantic and Mediterranean and have quite different life histories. Both are commercially exploited, but little is known about their stock structure. Fish otolith composition is thought to reflect both endogenous processes and external factors, some of which relate to the surrounding environment, and therefore may be used as a tool for stock discrimination. The elemental composition of sagittal otoliths was examined using both solution-based inductively coupled plasma mass spectrometry of the whole otolith and laser-ablation analysis of the otolith nucleus. The relative concentrations of strontium, barium, and copper in dissolved whole otoliths contributed to the discrimination between H. dactylopterus samples from different geographic areas. Surface analysis of the otolith nucleus did not allow separation of geographic groups. For M. merluccius, separate analyses of the whole otolith data for the Atlantic and Mediterranean samples gave a clear distinction of the different groups within each ocean basin. Analysis of the M. merluccius nucleus composition indicated some differences in elemental concentration among both Atlantic and Mediterranean samples. Magnesium and lead were important elements in separating the groups in the Atlantic, and barium, strontium, and lead were important in the Mediterranean. © 2005 International Council for the Exploration of the Sea. Published by Elsevier Ltd. All rights reserved.

European hake (Merluccius merluccius) were reared from eggs up to 245 days of age in temperature and salinity controlled stable conditions. The lapillus and sagitta of one of these fish were examined for microstructural features. The age derived from the increments support the daily nature of the hake sagittal increments starting the formation at day 8, probably related to the start of exogenous feeding. The lapillus shows a later increment formation. The sagitta otolith increments show rhythmical groupings and banding that are similar to wild fish. The accessory growth centres appear to be related to pectoral fin development and demersal habitat. The growth rates obtained are discussed. © 2005 Elsevier B.V. All rights reserved.

The larval growth and development of the European hake, Merluccius merluccius , was studied from field larvae. Larvae were collected in the northwestern Mediterranean on three cruises carried out during the peak spawning months (November 1998, September 1999 and November 1999). Like other species of the genus, these larvae are characterised by a well-developed anterior part of the body, head and trunk region. Nevertheless, yolk sac larvae are much more slender than larvae at notochordal flexion stages. In the present study we analysed the allometric relationships between several body measurements and body length. This is the first attempt to infer larval growth of Merluccius merluccius by means of sagittal otolith analysis. Our results show the change in the otolith shape from a lenticular otolith in early larvae to an almond-shaped otolith in larger larvae. Otolith diameter showed a power relation with larval size, with no significant differences between seasons. In spite of the sea surface temperature differences between the three periods of larval collection, the early growth estimates showed no significant differences. This was explained by the similarity in the temperature at the depths at which the larvae are located. Absolute growth rates in length were estimated by relating daily growth increments in otoliths and larval size (standard length). When using the whole larval size range the values obtained were similar to those found for other Merluccius species. Nevertheless, the present data evidenced that growth for larvae younger than 12 days is very low, showing a significant increase thereafter. This indicates that length is probably not the best parameter for describing the growth of hake larvae in the first days of life, as allometric analysis suggested.

Publicación online disponible en: http://www.icm.csic.es/scimar/index.php [EN] Data collected south-west of the Balearic Islands (Western Mediterranean) on two cruises, Quimera-I (October, 1996) and Quimera-II (May, 1998), were used to establish general ecological patterns in deep-sea fish assemblages. A total of 39 trawls were taken at depths between 400 and 1714 m. Fish assemblages were analysed in terms of species composition, ecological parameters and biomass spectra. Differences in species composition between cruises and depth (Upper slope: 400-800 m, Middle slope: 801-1400 m and Lower slope: 1401-1714 m depth) were evaluated using multivariariate analysis. The most important feature was the existence of a biomass peak at intermediate depths. Moreover, the analysis of the biomass spectra indicated the absence of large individuals at the shallower depth interval considered. To determine the causes of the biomass peak on the middle slope four hypothesis were explored: (1) species richness is higher on the middle slope; (2) the fish assemblage from the middle slope can be characterised by the highest abundance (number of fish/area); (3) species found on the middle slope are larger (the species assemblage is built up by larger species); and (4) there is a trend for the specimens of several species to be larger at the middle slope. The data gathered support that the biomass peak is better explained by the existence of abundance peaks of medium and large-sized species, and by the presence of some of the largest individuals of other large-sized species, in both cases related to specific depth size trends which do not always follow a bigger-deeper trend. [ES] Los datos analizados se han recogido al sureste de las Islas Baleares en dos campañas Quimera-I (Octubre, 1996) y Quimera-II (Mayo, 1996). Se realizaron un total de 39 pescas de arrastre entre 400 y 1714 m de profundidad. Se analizó la composición específica, parámetros ecológicos y espectros de biomasa de la comunidad íctica de profundidad. La característica más importante fue la existencia de un pico de biomasa a profundidades intermedias. El análisis de los espectros de biomasa indicó que no aparecían individuos de gran tamaño a menor profundidad. Las causas que pueden determinan la aparición de este pico de biomasa en el talud medio, se han examinado a partir de cuatro alternativas: (1) mayor riqueza específica a profundidades intermedias, (2) mayor abundancia de algunas especies en este intervalo de profundidad; (3) mayor tamaño de las especies, (4) tendencia de los ejemplares de algunas especies a ser más grandes a profundidades intermedias. La principal causa que puede explicar este pico de biomasa está relacionada con las respuestas individuales y específicas al gradiente batimétrico, ya que la abundancia de ciertas especies de tamaño medio y grande presenta un pico en esta profundidad, y además individuos de gran talla de otras especies de gran tamaño también son más abundantes. Ambas posibilidades no siempre se relacionan con una tendencia al aumento de la talla con la profundidad. This paper is a result of the European Project “Developing deep-water fisheries: data for their assessment and for understanding their interaction with an impact on a fragile environment” (EU FAIR Project CT 95-0655; European Commission DG XIV Fisheries).