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The ICES Workshop on ICES reference points (WKREF2) was tasked review the WKREF1 report and based on the outcome develop updated guidelines for the ICES reference points system and recommendations for ACOM consideration. The WKREF1 report has suggested 5 key recom- mendations to simplify and harmonise the ICES reference points framework representing a ma- jor change to the current guidelines. At WKREF2, we detailed discussions and four key concerns were raised about the proposed approach. The first related to the simplification of rules to define Blim. Around two thirds of category 1 stocks would end up as WKREF1 “Blim Type 2” where Blim would be set as a fraction of B0. The Allee effect or “depensation” maybe more important than previously thought and should be furthered explored for ICES stocks since it has important consequences for Blim. A number of challenges and issues around defining Blim using the current guidelines were documented. Some suggestions on improvement criteria were discussed including using classifiers to define spas- modic stocks and using change point algorithms to address non-stationary productivity regimes. However, further work is need to make these approaches operational and there was no consen- sus that the WKREF1 Blim types should replace the current guidelines. WKREF1 recommended that the FMSY proxy should be based on a biological proxies and should be less than the deterministic FMSY. It was pointed out that the stochastic FMSY estimated in EqSim for example, is lower than the deterministic FMSY and that the current guidelines ensure that the FMSY should not pose a more than 5% risk to Blim. A large amount of work described in WD 1 was carried out to develop an MSE framework to consistency and robustness test a candidate refer- ence point system for North East Atlantic stocks. However, WKREF2 recommended that further work needs to be carried out to condition and test the simulation framework before the conclu- sions could be adopted by ICES and incorporated into the guidelines. A number of considerations for defining MSY related reference points were discussed including using model validation and prediction skill to ensure that ICES provide robust and credible ad- vice. There is evidence that density dependence (DD) is important in the majority of ICES stocks (68% in recruitment and 54% in growth). The correct prediction of the shape and strength of density-dependence in productivity is key to predicting future stock development and providing the best possible long-term fisheries management advice. A suggested approach to use surplus production models (SPMs) to account for DD in FMSY was suggested and discussed but there was no consensus on whether that approach was appropriate. There was consensus that the FECO approach as a means of adapting target fishing mortality to medium-term changes in productiv- ity should be included in the guidelines subject to a benchmark and ACOM approval. While WKREF1 and 2 focused mainly on Category 1 stocks ToR c) called for a “simplified and harmonised set of guidelines for estimating MSY and precautionary reference points applicable in the advice framework across various ICES stock categories.” Ideally the ICES assessment cat- egories should provide equivalent risk across all stocks. This issue was discussed but no recom- mendations emerged. There was no consensus a revised reference point framework was proposed at WKREF2. How- ever, it was agreed that it should be presented here for further discussion at ACOM and other fora. The key feature of the suggested approach is that the stock status evaluation is treated in- dependent of the Advice Rule (AR). The main feature of the system is that the biomass trigger is not linked to a stock status evaluation, it is linked to the expected biomass when fishing at the target fishing mortality, in contrast to the current ICES approach. It also entailed that FMSY would also become an upper limit of fishing mortality and that the advised fishing mortality would be set at or lower than that level. WKREF2 did not discuss what to do in situations where SSB< Blim or alternative forms of HCR for the advice rule. Building community understanding and con- sensus around simplified and harmonised guidelines has yet to be achieved. A further workshop WKREF3 will be required to achieve that aim. The report includes 6 recommendations for ACOM consideration. ICES The main objective of the workshop was to review the recommendations of WKREF1 and con- sider how these might feed into a new reference points framework and guidelines for ICES. There were a number of presentations on the wider issues of best practice for reference points, the Allee effect, density dependence and the WKIRISH approach. The starting point was to try and develop a set of simplified and harmonised guidelines based on the WKREF1 report rather than evolving the current guidelines to include the WKREF1 conclusions. A key aspect of the meeting was to allow for discussions in order to build a shared understanding of the strengths and weakness of the current framework and of the new framework emerging from WKREF1. Published Non Refereed

[eng] Aphanopus carbo (Lowe, 1839), the black scabbardfish, is a benthopelagic teleost with high commercial value in the NE Atlantic, especially in Madeira Archipelago and mainland Portugal. Given its commercial interest and high susceptibility to overfishing, as a consequence of low fecundity and low growth rate, improving the knowledge on its life cycle and population dynamics is of uttermost importance for improving fisheries management and advice. Although some questions persist, the agreed assumption is that there is a unique stock that undergoes a clockwise migration around the NE Atlantic driven by feeding and reproduction. The available information that supports the hypothetical migratory cycle of A. carbo was reviewed in this Thesis and different methodological approaches were proposed to explore its life history traits and relate them with the migratory cycle, in order to increase information on the species for a sustainable knowledge-based fishery management, and to assess its population dynamics and spatial pattern in the NE Atlantic. Differences in fatty acids and stable isotopes concentrations in the muscle tissue of specimens from different areas supported the species hypothetical migratory cycle. Mature specimens showed a prevalence of polyunsaturated fatty acids (PUFA) which are related with high energetic demands, supporting the hypothesis that the black scabbardfish continues to feed during the spawning period. PUFA associated with a response to stress were high in specimens from the southernmost areas which might be related with the expected long-distance migrations. The analysis of sex steroids in blood serum confirmed their role as intrinsic triggers for gonadal maturation and spawning in black scabbardfish. Based on estradiol (E2) and testosterone (T) concentrations, some developing females from Madeira were clustered with females from mainland Portugal, giving evidence that not all developing females will have the ability to mature and reproduce during the current spawning season. The previous methodologies allowed relating biochemical traits with the species life cycle and compare them between geographical areas in a short and recent time-frame. To understand the species taxonomic and species spatial diversity throughout its life cycle, otoliths were used as chemical markers. In a first study, otolith trace element composition (TEC) was shown to be adequate to separate the two Aphanopus species that are mixed in landings from the Madeiran longline fleet. It was further demonstrated that quantifying Mg, Cr, Sr, and Ba in the otolith increment that corresponds to age-class 9 can be an effective way to identify the species using LA- ICPMS at relatively reduced costs. This technique could be applied to archived collections of otoliths to perceive the historical presence of A. intermedius in landings in Madeira, reconstruct species abundance time-series and infer if the species is moving northwards. Otolith microchemical analysis was also applied to infer the migratory movements of A. carbo along the NE Atlantic by quantifying certain trace elements at selected otolith zones that represent different life history stages, namely the core, age three, age five, and the edge. TEC in the otolith edge could discriminate the locations where specimens were caught, separating the northernmost from the southernmost areas. The longitudinal multivariate analyses of TEC also sustained the separation of the otoliths into two groups, but there is high mixing between them, which agrees with the migratory hypothesis. The existence of two natal sources was suggested from otolith core TEC analysis. 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 translate into changes in A. carbo’s stock assessment. [cat] Aphanopus carbo (Lowe, 1839), el peix sable negra, és un teleòste bentopelàgic amb un alt valor comercial a l'NE Atlàntic, especialment a l'arxipèlag de Madeira i a Portugal continental. Atès el seu interès comercial i la seva alta susceptibilitat a la sobrepesca, com a conseqüència de la baixa fecunditat i la baixa taxa de creixement, millorar la informació sobre el seu cicle de vida i la dinàmica de la població és de màxima importància per millorar la gestió i l'assessorament de la pesca. Tot i que hi ha preguntes sobre el seu cicle de vida i la dinàmica de la població que romanen sense resposta, la suposició acordada és que hi ha un estoc únic que experimenta una migració en sentit horari al voltant de l'NE Atlàntic impulsada per l'alimentació i la reproducció. La informació disponible que dóna suport al hipotètic cicle migratori de A. carbo es va revisar en aquesta tesi i es van proposar diferents enfocaments metodològics per explorar els trets de la seva història de vida i relacionar-los amb el cicle migratori, per tal d’incrementar la informació sobre la espècie per a una gestió sostenible de la pesca basada en el coneixement de les espècies i la seva dinàmica de població i patró espacial al Nord-Atlàntic. Les diferències en àcids grassos i les concentracions estables d’isòtops en el teixit muscular d’exemplars de diferents àrees van donar suport a l’hipotètic cicle migratori de l’espècie. Els exemplars madurs van mostrar una prevalença d’àcids grassos poliinsaturats (PUFA) que es relacionen amb elevades demandes energètiques, donant suport a la hipòtesi que el sable negre continua alimentant-se durant el període de posta. Els PUFA associats amb una resposta a l’estrès van ser elevats en exemplars de les zones més meridionals, cosa que podria estar relacionada amb les migracions esperades de llarga distància. L’anàlisi d’esteroides sexuals al sèrum sanguini va confirmar el seu paper com a desencadenants intrínsecs per a la maduració gonadal i la posta en sable negre. Basant-se en les concentracions d’estradiol (E2) i testosterona (T), algunes femelles en desenvolupament de Madeira es van agrupar amb femelles del Portugal continental, donant evidència que no totes les femelles en desenvolupament tindran la capacitat de madurar i reproduir-se durant la temporada actual de posta. Les metodologies anteriors permeten relacionar trets bioquímics amb el cicle de vida de les espècies i comparar-los entre àrees geogràfiques en un període de temps curt i recent. Per entendre diversitat taxonòmica i espacial de l’espècie al llarg del seu cicle de vida, es van utilitzar otòlits com a marcadors químics. En un primer estudi, es va demostrar que la composició d’elements traça d’otòlits (TEC) era adequada per separar les dues espècies d’Aphanopus que es barregen en els desembarcaments de la flota de palangre de Madeira. Es va demostrar, a més, que quantificar Mg, Cr, Sr i Ba en l'increment de l'otòlit que correspon a la classe d'edat 9 pot ser una manera eficaç d'identificar les espècies mitjançant LA-ICPMS a costos relativament reduïts. Aquesta tècnica es podria aplicar a col·leccions d’otòlits arxivades per percebre la presència històrica d’A. intermedius als desembarcaments a Madeira, reconstruir sèries temporals d’abundància d’espècies i inferir si l’espècie es mou cap al nord. L'anàlisi microquímica d'otolits també es va aplicar per inferir els moviments migratoris d'A. carbo al llarg de l'Atlàntic NE quantificant certs oligoelements en zones seleccionades d'otòlits que representen diferents etapes de la història de la vida, és a dir, el nucli, tres anys, cinc anys i la vora. El TEC a la vora de l’otòlit podria discriminar els llocs on es van capturar els exemplars, separant la zona més septentrional de la zona més meridional. Les anàlisis longitudinals multivariants de TEC també van mantenir la separació dels otòlits en dos grups, però hi ha una gran barreja entre ells, cosa que concorda amb la hipòtesi migratòria. L'existència de dues fonts natals es va suggerir a partir de l'anàlisi TEC del nucli d'otòlits. L’acceptació de les zones de posta tant del sud com del nord i dels moviments migratoris al llarg de l’NE Atlàntic en direccions nord i sud implica canvis en la hipòtesi migratòria actual que es podria traduir en canvis en l’avaluació d’estoc d’A. carbo. [spa] Aphanopus carbo (Lowe, 1839), el sable negro, es una especie bentopelágica con elevado valor comercial en el Atlántico NE, especialmente en Madeira y en Portugal peninsular. Dado su interés comercial y su elevada susceptibilidad a sobrepesca, como consecuencia de baja fecundidad y baja tasa de crecimiento, mejorar el conocimiento sobre su ciclo de vida y dinámica poblacional tiene máxima importancia para la gestión y asesoramiento de las pesquerías. Aunque quedan algunas cuestiones, la suposición acuerdada es que hay un stock único que hace una migración al redor del Atlántico NE en el sentido de las agujas del reloj estimulado por la reproducción y alimentación. La información disponible que sustenta la hipótesis del ciclo migratorio del A. carbo fue revisada en esta Tesis y se proponen diferentes abordajes metodológicos para explorar sus características vitales y relacionarlos con el ciclo migratorio, con el objetivo de aumentar la información sobre la especie en el sentido de un asesoramiento de la pesquería basado en el conocimiento, y para investigar su dinámica poblacional y patrón espacial en el Atlántico NE. Diferencias en la concentración de ácidos grasos y de isotopos estables en el tejido muscular de especímenes de diferentes áreas soportan el hipotético ciclo migratorio de la especie. En individuos maduros prevalecieron los ácidos grasos polinsaturados (PUFA) que están relacionados con elevada demanda energética, apoyando la hipótesis de que el sable negro sigue alimentándose durante la época de madurez sexual. Los PUFA, que están relacionados con la respuesta al estrés, alcanzaron niveles más altos en los especímenes de las áreas más a sur, pudendo estar relacionado con las migraciones de larga escala. Los análisis de esteroides sexuales en el suero sanguíneo confirmaron su papel como desencadenantes intrínsecos de la maduración de las gónadas y del desove del sable negro. Con base en la concentración de estradiol (E2) y de testosterona (T), algunas hembras en maduración capturadas en Madeira se agruparon con las hembras de Portugal peninsular, dando pruebas de que no todas las hembras en maduración tendrán la capacidad de madurar y reproducirse durante la presente época de desove. Las metodologías anteriores permiten relacionar trazos bioquímicos con el ciclo de vida de la especie y compararlos entre áreas geográficas. Para comprender la diversidad taxonómica y espacial de la especie a lo largo del ciclo de vida, los otolitos fueran usados como registradores químicos del ambiente donde el individuo vivió. En un primero estudio, se demostró que la concentración de elementos traza (TEC) de los otolitos es adecuada para separar las dos especies de Aphanopus que están mezcladas en los desembarques de la flota de palangre de Madeira. Además, se demostró que es posible separar las dos especies usando el LAICPMS con base en la cuantificación de los elementos Mg, Cr, Sr y Ba en el incremento del otolito que corresponde a la clase de edad 9. Esta técnica podrá ser empleada en colecciones archivadas de otolitos para demostrar la presencia histórica de A. intermedius en los desembarques en Madeira, reconstruir series temporales de abundancia de las especies y inferir si la especie se está desplazando hacia el norte. El análisis de microquímica de otolitos también fue empleada para inferir los movimientos migratorios de A. carbo alrededor del Atlántico NE por cuantificación de determinados elementos traza en zonas seleccionadas del otolito que representan diferentes fases de su historia de vida, a saber, el núcleo, los incrementos correspondientes a la edad tres y la edad cinco y el borde del otolito. Fue posible discriminar las áreas donde los especímenes fueron capturados con base en las TEC, separando las áreas más al norte de las más al sur. El análisis longitudinal multivariado de las TEC también suportó la separación de los otolitos en dos grupos, pero con elevada mezcla entre ellos, lo que corrobora la hipótesis de migración. La existencia de dos zonas de reproducción fue sugerida con base en el análisis de TEC en el núcleo de los otolitos. La aceptación de dos áreas de desove, en el sur y en el norte y de movimientos migratorios en el sentido norte y sur del Atlántico NE implica cambios en la actual hipótesis migratoria que podrán traducirse en cambios en el asesoramiento del stock de A. carbo.

The main objective of the Working Group on Biological Parameters (WGBIOP) is to review the status, issues, developments, and quality assurance of biological parameters for use in assess-ments and management that are in line with the requirements of end-users. In this final year of the three-year term, WGBIOP operated under challenging circumstances due to COVID-19 measures. The initial action plan was replaced by a more flexible one, where online plenary and subgroup meetings were spread over the year with intersessional work to finalize the proposed deliverables. WGBIOP continued the review of past exchanges and workshops under the remit of the working group. Since 2019, these calibrations on age, maturity, and larvae identification have been carried out in SmartDots, an online platform for sharing images and facilitating the reading of otoliths, staging of gonads, and identification of early life stages. Developments are underway to include an improved calculation of modal age and error matrices in the SmartDots standard report. WGBIOP investigated ways to incorporate error matrices into assessments and studied the effect of this inclusion together with stock assessors. Requests for new exchanges and workshops were reviewed, with a focus on stocks to be bench-marked in the coming years. Issue lists were scrutinized, problems identified, and information provided to stock coordinators via regular channels and through the Stock Identification Data-base (SID). Despite close cooperation with stock assessors and continued efforts, it has not been possible to further streamline the WGBIOP workflow with the benchmark process. This will be addressed with the Advisory Committee. The need for validation studies was stressed by the repeated low levels of agreement between readers of some stocks and recurring issues and recommendations to WGBIOP. Lack of resources is the main obstacle. As a first step for measures to prioritize validation studies, WGBIOP iden-tified precision, trueness, and feasibility of validation methods (as well as the urgency for the assessment). WGBIOP continued investigations into new life-history parameters for integrated assessment and advice in cooperation with end-users (Working Group on Integrative, Physical-biological and Ecosystem Modelling-WGIPEM and Regional Coordination Groups-RCGs). This included a standardization and quality assurance action plan for stomach sampling. Efforts have also been taken to streamline data and workflows across databases and groups. A step has been taken in the standardization of quality assurance procedures at the regional level. Institute-level overviews of methods and quality assurance protocols used for ageing and maturity are now available. Also, a new method for quality grading was developed, tested, and implemented in SmartDots.

Com o presente artigo, decorrente de uma pesquisa de mestrado, pretende-se, por meio da teoria dos registros de representação semiótica discutir, a partir de atividades encontradas em livros didáticos, aspectos relacionados às representações e apreensões em geometria tendo como objeto matemático a trigonometria no triângulo retângulo. Tais elementos auxiliam na compreensão de como se dá a aprendizagem de geometria e, consequentemente, seu estudo pode minimizar algumas dificuldades encontradas no percurso de ensinar. Nessa perspectiva, este trabalho se constitui a partir de atividades selecionadas em dois livros didáticos do 1º ano do ensino médio que fizeram parte do Programa Nacional do Livro Didático - PNLD (2014-2016). Nestas atividades foi possível observar a correlação com a teoria de registros de representação semiótica, de acordo com aspectos elencados da mesma. Dessa forma, espera-se contribuir com subsídios para a identificação em outras atividades que envolvam o objeto matemático em questão.

Gonads of the NE Atlantic black scabbardfish were examined to give an insight into the reproductive biology of this species. It was concluded that black scabbardfish had determinate fecundity because: (i) a distinct hiatus in oocyte size was observed between pre-vitellogenic and vitellogenic oocytes; (ii) vitellogenic oocytes increased in size during the spawning season; (iii) the number of vitellogenic oocytes did not increase during the spawning season; and (iv) the intensity of atresia was low in pre-spawning and spawning ovaries. Fecundity estimates ranged from 73 to 373 oocytes g-1 female. Comparison of developing ovaries from mainland Portugal and Madeira revealed that those from Madeira were more advanced in development, with more cortical alveoli stage oocytes and a higher gonadosomatic index. Starting in July, the reproductive development of all females from mainland Portugal was interrupted by a generalised atresia of developing oocytes. Completion of gametogenesis and spawning only occurred for fish from Madeira but some fish from this area also failed to complete oocyte development due to mass follicular atresia of vitellogenic oocytes. The percentage of Madeiran fish that failed to spawn due to follicular atresia ranged from 21.2% in 2006 to 37.4% in 2005. Las gónadas del sable negro del Atlántico nordeste fueron examinadas para conocer la biología reproductiva de esta especie. Los resultados sobre el tipo de fecundidad mostraron que la especie tenía una fecundidad determinada en base a los siguientes hechos: (i) hiato entre ovocitos previtelogénicos y vitelogénicos; (ii) aumento de tamaño de los ovocitos vitelogénicos durante el período de puesta; (iii) ausencia de incremento en el número permanente de ovocitos vitelogénicos avanzados durante el período de puesta y (iv) una pequeña atresia en los ovarios antes de la ovulación y durante ella. Las estimaciones de fecundidad se establecieron entre 73 y 373 ovocitos g-1 hembra. La comparación de los ovarios de hembras en desarrollo de aguas frente a Portugal continental y las de Madeira mostró una diferencia significativa en el tamaño medio de los ovocitos entre las dos áreas, y que las hembras de Madeira presentaron una mayor cantidad de ovocitos con alvéolos corticales y un índice gonadosomático mayor. A partir de julio y en hembras recolectadas frente a Portugal de continente, todos los individuos comenzaron a sufrir una atresia generalizada en sus ovocitos, mientras que en las aguas de Madeira, el ciclo reproductivo continúa hasta ovulación. Sin embargo, en algunas hembras de Madeira la gametogénesis también se paraliza y todos los ovocitos vitelogénicos son absorbidos vía atresia folicular. El porcentaje de hembras no reproductivas varió del 21.23% en 2006 al 37.4% en 2005.

Trabajo presentado en la ICES Annual Science Conference, celebrada en Riga, Letonia, del 19 al 23 de septiembre de 2016