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The present working document summarises the main results obtained from the ECOCADIZ-RECLUTAS 2021-10 Spanish (pelagic ecosystem-) acoustic-trawl survey conducted by IEO between 21st October and 07th November 2021 in the Portuguese and Spanish shelf waters (20-200 m isobaths) off the Gulf of Cadiz (GoC) onboard the R/V Ramón Margalef. The survey suffered a ten-day delay in relation to the usual starting dates. The survey’s main objective is the acoustic assessment of anchovy and sardine juveniles (age 0 fish) in the GoC recruitment areas. The 21 foreseen acoustic transects were sampled. A total of 18 valid fishing hauls were carried out for echo-trace ground-truthing purposes. Chub mackerel, anchovy and sardine were the most frequent captured species in the fishing hauls, followed by horse mackerel, bogue, Atlantic mackerel, Mediterranean horse mackerel and blue jack mackerel. Boarfish, longspine snipefish and pearlside showed an incidental occurrence in the hauls performed in the surveyed area. Sardine and chub mackerel showed the highest yields in these hauls, followed by anchovy and Mediterranean horse mackerel. Total and Spanish estimates of total NASC allocated to the “pelagic fish species assemblage” in this survey showed lower values than those recorded last year, whereas the Portuguese estimates showed an increasing trend. GoC anchovy was widely distributed in the surveyed area, although avoided the easternmost waters. Higher densities were recorded between Alfanzina and west of Cape Santa Maria, in the Algarve, and between Isla Cristina and Bay of Cadiz. Anchovy acoustic estimates in autumn 2021, 17 512 t and 1973 million fish, experienced 38% and 51% decreases in abundance and biomass, respectively, in relation to the last year’s autumn estimates and they were lower than their time-series averages. The population was composed by fishes not older than 2 years. As usual, the bulk of the population, including juveniles, was located in Spanish waters. Age-0 anchovies accounted for 83% (1629 million) and 69% (12 063 t) of the total estimated abundance and biomass, respectively. Age-0 estimates experienced a similar decreasing trend than the one showed by the whole population in relation to the historical peak recorded in 2019, but with values close to the time-series average. GoC sardine was widely distributed all over the surveyed area (also avoiding the easternmost waters) and recorded a relatively high acoustic echo-integration in autumn 2021 as a consequence of the occurrence of dense mid-water schools in the Algarve coastal and inner shelf waters (20-78 m). Abundance (2986 million fish) and biomass (151 320 t) estimates were the second historical records within its respective series, although they represented 83% and 38% decreases in relation to the last year’s estimates. GoC sardine population was mainly concentrated in Portuguese waters. Age-5 group was the oldest age group in the population, although the occurrence of fishes older than 4 years was incidental. The population was mainly composed by fishes belonging to the age-0 to age-2 groups. Juvenile sardines (age-0 group) were not the dominant group, accounting for 21% (638 million) and 9% (12 854 t) of the total abundance and biomass, respectively. The bulk of this juvenile fraction was recorded in Spanish coastal waters. Chub mackerel was also widely distributed in the surveyed area, but showing higher densities in three between Cape San Vicente and Mazagón. Chub mackerel estimates were of 13 115 t and 106 million fish, accounting for 64% and 43% strong decreases in relation to the estimates in the previous year and with the above values being lower than their time-series average. The population was mainly concentrated in Portuguese waters and it was composed by fishes not older than 5 years, with the age-1 group being the dominant one. Age-0 fish was the second most important age group in the estimated population ((24%, 26 million fish, and 13%, 1689 t, of the total abundance and biomass estimates). The bulk of the age-0 and age-1 groups were recorded in the Portuguese waters, whereas older age-groups were more frequent in Spanish waters.

The present working document summarises a part of the main results obtained from the Spanish (pelagic ecosystem-) acoustic survey conducted by IEO between 01st and 14th August 2020 in the Portuguese and Spanish shelf waters (20-200 m isobaths) off the Gulf of Cadiz (GoC) onboard the R/V Miguel Oliver. The 21 foreseen acoustic transects were sampled. A total of 26 valid fishing hauls were carried out for echo-trace ground-truthing purposes. Four additional night trawls were conducted to collect anchovy hydrated females (DEPM). This working document only provides abundance and biomass estimates for anchovy, sardine and chub mackerel, which are presented without age structure. The distribution of all the mid-sized and small pelagic fish species susceptible of being acoustically assessed is also shown from the mapping of their back-scattering energies. GoC anchovy acoustic estimates in summer 2020 were of 5153 million fish and 44 877 tones, with the bulk of the population occurring in the Spanish waters. The current biomass estimate becomes in the second historical maximum within the time-series. The estimates of sardine abundance and biomass in summer 2020 were 1923 million fish and 50 721 t, estimates close to the historical average, but lower than the values estimated last year and the most recent maxima reached in 2018. A total of 32 854 t and 448 million fish were estimated for Chub mackerel, estimates similar to the most recent ones and very close to the time-series average.

The Daily Egg Production Method (DEPM) to estimate the Anchovy Spawning Stock Biomass (SSB) in the Gulf of Cádiz (ICES, Subdivision 9a South) is conducted by Spain (Centro Nacional Instituto Español de Oceanografía, CSIC) every three years, since 2005. BOCADEVA 0720 is the sixth survey of the historical DEPM series for anchovy in the Gulf of Cádiz and was delivered on board R/V Ramón Margalef (CNIEO) from the 9th to the 17th of July 2020. The surveyed area extended from Strait of Gibraltar to Cape San Vicente (Spanish and Portuguese waters in the Gulf of Cadiz). Plankton samples, along a grid of 21 transects perpendicular to the coast were obtained for the spawning area delimitation and density estimation of the daily egg production. The survey objectives also included the characterization of the oceanographic and meteorological conditions in the study area. The samples to estimate adult parameters (sex ratio, female mean weight, batch fecundity and spawning fraction) were obtained in the acoustic survey “ECOCADIZ 2020-07”, carried out during the same period. This working document provides a d escription of the survey, laboratory analysis and estimation procedures used to obtain the Gulf of Cadiz Anchovy SSB by DEPM for 2020 in the South-Atlantic Iberian Stock.

The present working document summarises a part of the main results obtained during the ECOCADIZ-RECLUTAS 2021-10 Spanish (pelagic ecosystem-) acoustic survey. The survey was conducted by IEO between 21st October and 07th November 2021 in the Portuguese and Spanish shelf waters (20-200 m isobaths) off the Gulf of Cadiz (GoC) onboard the R/V Ramón Margalef. The survey suffered a ten-day delay in relation to the usual starting dates, resulting in ending dates very close to the starting ones of the WGACEGG meeting. Therefore, no acoustic estimates were available at the time of WG meeting. The survey’s main objective is the acoustic assessment of anchovy and sardine juveniles (age 0 fish) in the recruitment areas of the GoC. The 21 foreseen acoustic transects were sampled. A total of 18 valid fishing hauls were carried out for echo-trace ground-truthing purposes. This working document only provides information on the results of these hauls in terms of species-specific occurrences, yields in numbers and weight, size ranges, mean size and mean weight in catches.

The present working document summarises a part of the main results obtained during the ECOCADIZ-RECLUTAS 2020-10 Spanish (pelagic ecosystem-) acoustic survey. The survey was conducted by IEO between 02nd and 21st October 2020 in the Portuguese and Spanish shelf waters (20-200 m isobaths) off the Gulf of Cadiz (GoC) onboard the R/V Ramón Margalef. The survey’s main objective is the acoustic assessment of anchovy and sardine juveniles (age 0 fish) in the recruitment areas of the GoC. The 21 foreseen acoustic transects were sampled. A total of 22 valid fishing hauls were carried out for echo-trace ground-truthing purposes. This working document only provides abundance and biomass estimates for anchovy, sardine and chub mackerel, which are presented without age structure. The distribution of all the mid-sized and small pelagic fish species susceptible of being acoustically assessed is also shown from the mapping of their back-scattering energies. GoC anchovy acoustic estimates in autumn 2020, 36 070 t and 3197 million fish, showed a decrease in relation to the historical peak recorded the last year, but they were either close (abundance) or even higher (biomass) than the time-series average. As usual, the bulk of the population, including juveniles, was located in Spanish waters. GoC sardine experienced a huge increase in autumn 2020, rising up to its time-series maximum and yielding 208 400 t and 5451 million fish, with similar regional contributions to the population and with the juveniles being located in the Spanish coastal waters. Chub mackerel estimates were of 22 918 t and 295 million fish, representing a slight decrease compared with the last year, but still above the time-series average.

Educación

Based on the results of a full-scale otolith exchange held in 2014, the Working Group on Biological Parameters (WGBIOP 2015) identified the need for an age reading workshop on European Anchovy otoliths (WKARA2). This workshop (chaired by Andres Uriarte, Spain, Begoña Villamor, Spain and Gualtiero Basilone, Italy), was held in Pasaia, Gui-puzcoa (Spain) from the 28 November to 2 December 2016. Five countries took part in this workshop (Spain, Italy, Croatia, Greece and Tunisia), with a total of 16 participants from 9 laboratories. In total 17 areas/stocks were analysed (4 from the Atlantic area and 13 from Mediterranean Sea) The aim of this workshop was to review the information on age determination, discuss the results of the previous exchange (2014), review the validation methods existing on these species, clarify the interpretation of annual rings and update the age reading pro-tocol and a reference collection of well-defined otoliths. Age validation studies, in the Bay of Biscay and preliminary validation studies in Divi-sion 9a, Alboran Sea and Strait of Sicily areas were presented, including a compilation of age validation studies of this species as well in the literature. There are several ar-eas/stocks in which validations of the anchovy annual age determination have not been done yet. Due to the poor percentage of agreement achieved in the 2014 Exchange (mean agree-ment of 66%; mean CV of 58%), the workshop proceeded with a detailed and joint dis-cussion on the growth patterns shown by otoliths from the different areas to find out the major reasons for discrepancies in age determination among readers. At the same time, the joint discussion allowed a better understanding of the pattern of otolith growth in-crements by areas to improve the guidelines for their interpretation. The discussions on examples among otoliths which generated discrepancies in the age determination led to conclude that there were two major sources of disagreements: a) Divergent otolith inter-pretation: different interpretations of the marks, growth bands and edges in terms of their conformity with the expected growth pattern of the anchovies, seasonal formation of the otolith by ages and most common checks. and b) wrong application of the age allocation Rules: it was evidenced during the workshop that for the birthdate first July (or first June) in some cases the age determination rule was not being correctly applied during the first half of the year (from January to June). Following the workshop discussions there has been a progressive change in the percep-tion of the growth pattern applicable to these anchovy otoliths in many areas which led to some revisions of the otolith interpretation and assigned ages, by which growth at ages 0 and 1 are far prominent than at older ages and the occurrence of checks became more frequently admitted. Furthermore, there have been evidences that the age determination rules have in some instances been inconsistently applied. All these evidences led to con-clude on the need to review past age determinations. Although this task should be de-layed until running an exchange in 2018 to be sure that all the readers apply the protocol and the current criteria of this workshop coherently, since current criteria would change the otoliths interpretation and the age determination in many areas. In addition, for the Mediterranean regions the convenience of midyear birthdates was put in question in comparison with the simplicity of the conventional birthdates at first of January (as these anchovies are in the northern hemisphere). As a corollary of the former statements, intercalibration exercises by areas, for the differ-ent countries taking part in the age reading of the same exploited stock, are still required. Finally, this Workshop adopted a common protocol for all areas in order to standardize the anchovy age assignments and to improve the coherence of the age estimates. An agreed collection of otoliths by areas were produced and upload to the Age Readers Fo-rum.

The present working document summarises the main results from the Spanish (pelagic ecosystem‐) acoustic survey conducted by IEO between 2nd and 13th August 2013 in the Portuguese and Spanish shelf waters (20‐200 m isobaths) off the Gulf of Cadiz onboard the R/V “Cornide de Saavedra”. The survey dates were somewhat delayed in relation to the usual ones and to the anchovy (Engraulis encrasicolus) peak spawning as well. Abundance and biomass estimates are given for all the mid‐sized and small pelagic fish species susceptible of being acoustically assessed according to their occurrence and abundance levels in the study area. The distribution of these species is also shown from the mapping of their back‐scattering energies. The bulk of the anchovy population was concentrated in the Spanish shelf, with a residual nucleus to the west of Cape Santa Maria. A delay of the usual survey dates may be the reason of a higher relative importance of smaller anchovies in the population as a probable consequence of the incorporation of the first waves of recently recruited juveniles to the adult population. The total biomass estimated for anchovy was 8.5 thousand tonnes (609 million fish), the lowest estimate in its series. Sardine showed a distribution pattern almost complementary to that described for anchovy, with higher densities occurring over the inner‐middle shelf of both extremes of the surveyed area, mainly west to Cape Santa Maria, and in shallower waters than anchovy. Sardine yielded a total of 9.7 thousand tonnes (232 million fish). The 2013 sardine estimate was also the lowest one in its series and corroborates a clear recent decline in the population which has also been evidenced by the PELAGO surveys. Chub mackerel was present all over the surveyed area although showed a more “oceanic” distribution in the westernmost waters. The species was the most important in terms of assessed biomass, rendering estimates of 31.3 thousand tonnes (333 million fish). Acoustic estimates for jack and horse‐mackerel species (Trachurus spp.), and bogue (Boops boops) are also given in the WD. No acoustic estimates either for mackerel S. scombrus or round sardinella (Sardinella aurita) were computed because their incidental occurrence in the study area during the survey.

El propósito general de este proyecto es llevar a cabo el diseño, mediante la utilización de sistemas y componentes existentes en el mercado, de un Sistema de Alimentación Ininterrumpida (SAI) de potencia mediana-grande destinado a la alimentación de equipos de Telecomunicación alimentados en tensiones de 230Vca, -48Vcc y +24Vcc. El SAI es de la máxima fiabilidad posible, dispone de tolerancia a fallo, es compacto, modular, ampliable en potencia, del máximo rendimiento posible, optimiza su explotación, tanto localmente como remotamente, disponiendo de telesupervisión del funcionamiento de todos sus componentes, y telemando (apertura y cierre remotos) de todos los circuitos de alimentación a las cargas alimentadas por él. Para conseguir los objetivos marcados se analizarán los equipos y componentes existentes en el mercado capaces de formar parte del SAI y que dispongan de las mejores prestaciones en relación con los objetivos que se persiguen. La metodología empleada consiste en dividir el Sistema de Alimentación en distintos Bloques, que ensamblados e interconectados entre sí, permitan configurarlo cumpliendo con los objetivos. Todos los equipos y componentes seleccionados para la configuración de los distintos Bloques son de la máxima fiabilidad y rendimiento posibles. El cumplimiento de los objetivos marcados para el SAI permite obtener un ahorro económico, tanto en costes de energía consumida de la Red de la que se alimenta, (dada la optimización del rendimiento y la minimización de las pérdidas en potencia con la consecuencia de reducción de las necesidades de refrigeración de la instalación), en los costes relacionados con el personal de explotación y mantenimiento (dada la facilidad de explotación y reparación), y en los costes relacionados con el espacio ocupado por el Sistema en la instalación donde se ubique (dado su tamaño compacto). La optimización del rendimiento y la minimización de las pérdidas de potencia llevan consigo una reducción de las emisiones de CO2. Con el SAI desarrollado se han conseguido de una forma satisfactoria todos los objetivos descritos anteriormente. Abstract: The general purpose of this project is to design, using existing systems and components in the market, a medium-large power Uninterrupted Power Supply (UPS) for the supply of Telecommunication equipment powered by voltages of 230Vac, -48Vcc and +24Vcc The UPS is of maximum reliability, has fault tolerance, is compact, modular, expandable in power, of the maximum possible efficiency, optimizes its operation, both locally and remotely, having telesupervision of the operation of all its components, and remote control of all the circuits that feed the loads. To achieve the objectives, the equipment and components existing in the market, capable of forming part of the UPS, which have the best characteristics, will be analyzed. The methodology used consists of dividing the UPS into different subsystems, which, assembled and interconnected, allow it to be configured in accordance with the objectives. All equipment and components selected for the configuration of the different subsystems are of maximum reliability and maximum efficiency. The fulfillment of the objectives set for the UPS allows obtaining an economic saving in energy costs consumed by the Electrical Network from which it is fed (given the optimization of the performance and the minimization of the potential losses with the consequence of reducing the cooling needs of the installation), in the costs related to the maintenance personnel (given the ease of operation and repair), and in the costs related to the space occupied by the System in the installation where it is located (given its compact size ). The optimization of the performance and the minimization of the losses of power entail a reduction of the CO2 emissions. With the UPS developed all the objectives described above have been achieved.