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Scientific, Technical and Economic Committee for Fisheries (STECF) – Stock Assessments: demersal stocks in Adriatic, Ionian and Aegean Seas and straits of Sicily (STECF-22-16).
No full textCommission Decision of 25 February 2016 setting up a Scientific, Technical and Economic Committee for Fisheries, C(2016) 1084, OJ C 74, 26.2.2016, p. 4–10. The Commission may consult the group on any matter relating to marine and fisheries biology, fishing gear technology, fisheries economics, fisheries governance, ecosystem effects of fisheries, aquaculture or similar disciplines. This report documents the outcomes of STECF Expert Working Group 22-16: 2022 stock assessments of demersal stocks in the Adtiat ic, Ionian and Aegean Seas from the meeting held in Rome from 17th to 23th October 2022. A total of 16 fish stocks were considered and 15 were fully evaluated. The EWG reports age based assessments, target Fs, with short term forecasts for 9 stocks of the remaining 6 stocks, four of these do not have short term forecasts as he assessments are not suitable, and one is given ICES category 3 advice. The content of the report gives the STECF terms of reference; the basis of the evaluations; assessments, summaries of state of stock and advised catch or F based on either the MSY approach for assessed stocks and category 3 based advice for those without assessments. The report contains the full stock assessment reports for the 14 assessments, the exploration of assessments and category 3 evaluations for the remaining stock. The report also contains the STECF observations and conclusions on the assessment report. These conclusions come from the STECF Plenary meeting November 2022.European UnionPublishedReferee
Scientific, Technical and Economic Committee for Fisheries (STECF), Evaluation of economic indicators and closure areas in the western Mediterranean. (STECF-23-01).
No full textCommission Decision of 25 February 2016 setting up a Scientific, Technical and Economic Committee for Fisheries, C(2016) 1084, OJ C 74, 26.2.2016, p. 4–10. The Commission may consult the group on any matter relating to marine and fisheries biology, fishing gear technology, fisheries economics, fisheries governance, ecosystem effects of fisheries, aquaculture or similar disciplines. This report is the 10th of a suite of STECF EWG reports dedicated to the evaluation of the implementation of the Western Mediterranean Sea Multi-Annual management Plan (hereafter, MAP), following EWG reports 18-09, 18-13, 19-01, 19-14, 20-13, 21-01, 21- 13, 22-01 and 22-11. The group was requested to continue the development of socio-economic indicators to be used in the evaluation of management measures for the West Med MAP in both West Med management units (EMU1 and EMU 1) (TOR1). Two roadmaps were discussed, a short term approach and a long term approach which would consider the expansion of all the mixed-fisheries bio-economic models to both management units. As a first step, the group focused on the proposal of harmonizing the economic indicators across the models implemented (TOR2). The group was than requested to further develop the approach implemented during EWG 22-01 to identify persistence hotspots of the six target species of the West Med MAP using scientific survey data (MEDITS) in combination to commercial spatial data (VMS joined with logbooks), to test existing and additional closure areas (TOR 3). The group was also requested to revise Article 8 of the 2023 fishing opportunities for the West Med MAP (COUNCIL REGULATION (EU) 2023/195), which lists the compensation mechanisms that MSs can implement within the West Med MAP to obtain additional fishing days in 2023 (TOR 4). For TOR 1 a roadmap was discussed and proposed on how to organise the work on socio-economic assessments for the West Med MAP in 2023. The EWG suggests that here should be a three-step process: a scoping exercise (done with EWG 23- 01), a meeting with stakeholders in the middle of the year to discuss their perception of the socio-economic consequences of measures of the West Med MAP and the running of scenarios during EWG 23-11 with results from socio-economic assessments. The EWG notes that the modellers have only the five-day meeting in September to run scenarios. Therefore, it would be crucial for the success of the assessments that the 6 scenarios provided by DG Mare for the EWG 22-11 and with some adjustments for EWG 23-01 will not change for EWG 23-11. It is crucial because those scenarios are already implemented in the models and the implementation of new scenarios would take a lot of time. The EWG proposes to run a few additional scenarios with only one measures to separate impacts of certain measures from the six scenarios where a mixture of measures is included. This would hopefully allow to give an indication what additional efforts may be necessary to reach MSY (in 2025 but also beyond in case the objective is not reached by 2025) and when gains from the implementation of the West Med Plan could be expected. The EWG observes that modelers need to put in additional effort and resources to improve the models for an improved assessment of the West Med MAP. The models were not originally developed for the assessment of the West Med MAP and only cover parts of the area of the Western Mediterranean. Such an improvement of the models could also include work to provide longer-term socio-economic assessments of measures where modelers need to take additional assumptions into account. The EWG notes that it would be beneficial if modelers receive a basic list of assumptions for key economic variables before the EWG 23-11 meeting in September. In 2022, for example, the increased fuel costs were an important factor regarding the economic performance of the fleets. In 2023 fuel costs have decreased but there are other cost categories with a substantial increase. The EWG concludes that DG Mare should not change the 6 provided scenarios substantially before the EWG 23-11 meeting in September. This would allow the modelers to run the models during the meeting and provide the socio-economic results. The EWG concludes that STECF and DG Mare should further discuss how resources could be provided to modelers to improve the applied models. The EWG concludes that the chairs of EWG 23-01 and 23-11 will provide a list of assumptions for the implementation of the models regarding key variables for the socio-economic assessments (short- and long-term). For TOR 2 the EWG discussed what variables and indicators the applied models include and provide. From that discussion a list of indicators was developed for which modelers will be able to provide results in the EWG 23-11 report. The EWG concludes that a list of indicators is provided for which EWG 23-11 will present results in autumn 2023. For TOR 3 the EWG notes that new closure areas for 2023 were implemented only by Spain (EMU 1) (Orden APA/80/2023). All closures areas implemented under the West Med MAP are described to allow testing if their implementation would reduce the catches of juveniles and adults of the six target species of the MAP by 15-25%. The EWG notes that the methodology followed to prioritise, developing and updating closure areas based on their conservation value on the basis of existing closures, proposed closures from EWG 22-01 and new proposals developed by EWG 23-01 based on updated MEDISEH layers is similar to the one used during EWG 22- 01. Updated MEDISEH layers were used for priority species (ARA, MUT and HKE) in combination with old MEDISEH layers for other species and distribution maps of commercial effort from EWG 22-01. Calculation of the percentage of the trawlable GSA area closed to fishing is higher in EMU 1 than EMU 2, therefore the estimation of additional closure areas on top of the existing ones foccused on this management unit. Additional closure areas to test were based on persistence hotsposts from survey data and from areas of high effort in order to impact directly on the reduction of fishing mortality. The EWG notes that the exisiting and additional closures could be tested only in EMU 2 and GSA 7 as for GSA 1, 5 and 6 the extension of the spatially-explicit model ISIS-Fish is not complete yet and it is still limited to a single species (HKE). The EWG notes that closure areas in GSA 7 were tested with two different methods. A static method comparing effort distribution data before and after the closures implementation in 2020, and a dynamic method applying ISIS-Fish. The first method showed how the establishment of the spatio-temporal closure imposed a strong seasonal constraint to the fishing effort in the Gulf of Lions, and that the fishermen community responded quite well to the new rule, although vessels increased their fishing effort along the closure border, with a typical « fishing the line » pattern, especially in the fall. The second model showed that introducing an additional closure did not improve the rebuilding of the hake stock, while changing the closures from seasonal to permanent suggested the strongest effect. The EWG notes that in EMU 2 that temporal closures for the whole fleet reduce global effort while additional spatial closures increase effort towards coastal areas (depths <200m) specifically for fleet segments <18m. Fishing mortality instead is reduced for all species by the introducion of additional closures, specifically those targeting high effort areas, although Fmsy is reached only for ARS and DPS and for already underexploited stocks (MUT 10 and NEP). The EWG concludes that provided that the area in GSA 7 have been chosen according to juvenile hake catch, we can expect that, given the strong observed response of the fishermen community, the closure in GSA7 has the potential to positvely impact the hake recruitment in the long run. Still, two years of implementation remains a short time-scale to observe strong changes in a long- lived stock. More time, observations and analysis will be necessary in the future to further quantify the efficiency of these closures. The EWG concludes that no positive effects on the stocks biomasses are observed in EMU 2 indipendently of the scenarios applied. For TOR 4, the EWG notes that both definitions of “juveniles” and “spawners” are not clearly stated in the Regulation (95/2023) making a bit challenging the evaluation of the criterions. A similar consideration could be done for the term “catch reduction” which is never specified whether it should be considered in number or weight. The EWG could not fully understand if the compliance with the criterions in term of results achieved would be evaluated at some point in the process. The EWG reports that for point a) the literature suggests that the requested threshold of at least 25% of reduction in hake juveniles seems not achievable. For point b) only for Blue and red shrimps the introduction of a 50mm square mesh size seems to lead to the decrease of specimens below 25mm CL at least of 25%. However, for vessels targeting Blue and red shrimps in EMU2, this is a mixed fisheries targeting also Giant red shrimp and it is not applicable to have two different size thresholds for the two species. The EWG suggested that the criterion should be revised providing just one size threshold, ideally selecting the one proposed for blue and red shrimps. According to the IMPLEMED results the same conclusion of point a) can be shared with point c) when a grid of 20mm space bar is used. For point d) EWG cannot find any clear evidence or results which corroborate the fact that specific closures could lead to a reduction in juveniles and spawners at the level requested by the criterion. Point e) refers to an increase of the MCRS for hake (26cm TL) which if not linked with some additional technical measures should just lead to an increase of discards of hake and, likely, black market. For point f), the EWG agreed the temporal closures implemented by Spain and France under the West Med MAP are following the criterion. The EWG concludes that considering the available knowledge and the analysis done during the meeting only the requests based on point b) and point f) could be considered fully in compliance with what the criterion stated, for point d) there weren’t enough information to be fully evaluated if it is feasible or not while the others criterion seems to be not corroborated by the available literature.PublishedReferee
Scientific, Technical and Economic Committee for Fisheries (STECF) – Stock Assessments: demersal stocks in the western Mediterranean Sea. (Version 1.2) (STECF-22-09).
No full textCommission Decision of 25 February 2016 setting up a Scientific, Technical and Economic Committee for Fisheries, C(2016) 1084, OJ C 74, 26.2.2016, p. 4–10. The Commission may consult the group on any matter relating to marine and fisheries biology, fishing gear technology, fisheries economics, fisheries governance, ecosystem effects of fisheries, aquaculture or similar disciplines This report documents the outcomes of STECF Expert Working Group 22-09: 2022 stock assessments of demersal stocks in the western Mediterranean Sea from the meeting held remotely from 5th to 11th September 2022. A total of 20 fish stocks considered and 18 were fully evaluated. Two stocks had prior advice from 2021 with catch advice for 2022 and 2023, and this is reiterated here. The EWG reports age based assessments, target Fs, with short term forecasts for 15 of the remaining 18 stocks, of these 15, 12 were also analysed for biomass reference points. Catch advice for three stocks was based on ICES category three evaluations of biomass indices. The content of the report gives the STECF terms of reference; the basis of the evaluations; assessments, reference point calculations; summaries of state of stock and advised catch or F based on either the MSY approach for assessed stocks and category 3 based advice for those without assessments. The report contains the full stock assessment reports for the 15 assessments, the exploration of assessments and category 3 evaluations for the remaining three stocks. The report also contains the STECF observations and conclusions on the assessment report. These conclusions come from the STECF Plenary meeting November 2022.European UnionPublishedReferee
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Conservation and management of Florida Spotted Seatrout (Cynoscion nebulosus). How can a detailed understanding of the environmental and biological factors influencing population dynamics help to better manage the species?
Get PDFSpotted seatrout populations have been historically exploited to various degrees. A recent shift from a sizeable commercial exploitation to a largely recreational exploitation has resulted in the deterioration in data quality due to the greater diffi culty in obtaining suitable data for stock assessments from such fi sheries. At the same time there has been increasing concern about state of the stocks from an environmental aspect, leading to increased research interest in the species to improve conservation and management. Although the data has been collected for different and specific purposes, it frequently contains valuable additional information on the biology of the species and on trends in population dynamics over time. Extracting such information is often hampered by inconsistent or intermittent data collection and the conflict between the original sampling design needs and the requirements of long-term investigations into the population dynamics of seatrout. This study investigates juvenile habitat requirements, reproduction, variation in growth and trends in recruitment using data from three of the main estuarine areas in Florida - Charlotte Harbor, the Indian River lagoon and Tampa Bay - to investigate what additional information can be extracted from the available data provided by the fi sheries independent and fi sheries dependent monitoring programs as well as data collected for additional biological studies over the last 20 years. Generalised additive model (GAM) were chosen as an approach, because of their ability to elucidate the form of relationships for which the underlying functional form is unknown and their ability to cope with a variety of error structures. However, it is exactly this flexibility which also makes them vulnerable to inconsistencies in the sampling design. Therefore to derive robust quantitative models suitable as an evidence base for management bootstrap, independent data verifi cation and other modelling approaches in conjunction with a rigorous analysis of model assumptions and a critical review of the biology were undertaken. Results indicate that it is firstly possible to use GAMs to develop quantitative models of distribution and habitat usage suffi ciently robust to be transferable between estuarine systems so that they can be used to evaluate the habitat value and the anthropogenic risk in estuaries currently not monitored for seatrout populations. Secondly, the reproductive models suggest that the temporal variation in reproduction between estuaries is driven by differences in the environmental conditions rather than genetic or population differences and that therefore the model should be universally applicable if environmental conditions are known. Thirdly, in contrast variation in growth, although similar between populations with regards to the effect of age sex and season does differ by cohort and year, so that neither a single growth model for a population, nor even one for different cohorts within a population should be used when assessing population dynamics in the different management units. Lastly, recruitment indices, based on the year effect from habitat models provide robust measures of relative abundance even in the presence of considerable changes in the sampling design, when models are suitably constrained. The current stock assessment methodology is unable to accurately refl ect the interannual differences in cohort strength within different populations, because management units span more than one estuary with discrete population trends and because age information is aggregated in periods greater than one year. Generalised additive models can then extract significant amounts of additional information and provide robust management tools provided the evaluation of the model properties have been suffi ciently rigorous. A more integrated approach to the management of seatrout in Florida is therefore possible, but the magnitude of the impact on management of the species is still unclear in the absence of sufficiently detailed estuarine hydrodynamic and stock assessment models
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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