Acoustic assessment and distribution of anchovy, sardine and chub mackerel in ICES Subdivision 9a South during the ECOCADIZ-RECLUTAS 2021-10 Spanish survey (October 2020) with notes on the distribution of other pelagic species. Preliminary information.

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

Acoustic identification of krill (Nyctiphanes couchii & Nematoscelis megalops) in the Spanish Mediterranean Sea

During the 2015 routine acoustic survey for stock assessment carried out in the Spanish Mediterranean continental shelf, krill swarms were localized in two different places using an EK60 scientific echosounder, operating at multiple frequencies. Biological identification was performed by mean of a plankton net (bongo 90) equipped with two different mesh sizes (500 to 2000 microns). Although krill frequency response was similar in both localizations, samples analysis revealed the presence of two different species: Nyctiphanes couchii (Bell, 1853) and Nematoscelis megalops (Sars, 1883)

Relationship between anchovy (Engraulis encrasicolus) recruits and anchovy spawners estimated from acoustic surveys in Northwestern Mediterranean Sea

In this study we present the abundance and biomass of European anchovy (Engraulis encrasicolus) estimated by acoustic methods in the Northwestern Mediterranean Sea (GSA06). during two different seasons, winter, the anchovy recruitment season and summer, when the majority of the anchovy stock belongs to the spawner fraction of one year-old. Four standardized acoustic surveys carried out covering the study area during two consecutive years (every six months), two of them during the peak of anchovy recruitment and the other two during the peak of anchovy spawn, allow to observe changes in the anchovy stock abundance and biomass in this area. Acoustic data from summer and winter echo-surveys were analyzed in an effort to better understand the life cycle of anchovy in relation to the survival during its first year of life

Acoustic assessment and distribution of the main pelagic fish species in ICES Subdivision 9a South during the ECOCADIZ-RECLUTAS 2020-10 Spanish survey (October 2020)

The present working document summarises the main results obtained from the ECOCADIZ-RECLUTAS 2020-10 Spanish (pelagic ecosystem-) acoustic-trawl survey 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 GoC recruitment areas. The 21 foreseen acoustic transects were sampled. A total of 22 valid fishing hauls were carried out for echo-trace ground-truthing purposes. Chub mackerel, anchovy, mackerel and sardine were the most frequent captured species in the fishing hauls, followed by bogue, horse 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, anchovy, chub mackerel and mackerel showed the highest yields. Total and regional estimates of total NASC allocated to the “pelagic fish species assemblage” in this survey become the historical records in their time-series. Such estimates are the result of the relatively high acoustic contributions of sardine (both in Portuguese and Spanish waters), anchovy (in Spanish waters), and chub mackerel (in Portuguese waters). GoC anchovy was widely distributed in the surveyed area, although higher densities were recorded between east of Cape Santa Maria and Bay of Cadiz. 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. The population was composed by fishes not older than 3 years. As usual, the bulk of the population, including juveniles, was located in Spanish waters. Age-0 anchovies accounted for 75% (2385 million) and 58% (21 060 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 the year before, but with values close to the time-series average. 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. Age-6 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 the dominant group, accounting for 45% and 24% of the total abundance (2454 million) and biomass (49 259 t), respectively. This age-group also recorded its historical maximum in 2020. 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. The population was composed by fishes not older than 3 years, with the age-1 group being the dominant one (73%, 216 million, and 75%, 17 082 t, of the total abundance and biomass). Age-0 fish was the second most important age group in the estimated population (17%, 51 million fish, and 12%, 2759 t, of the total abundance and biomass estimates). The bulk of the age-0 (73%) and age-1 groups (74%) was recorded in the Portuguese water

Acoustic assessment and distribution of the main pelagic fish species in ICES Subdivision 9a South during the ECOCADIZ-RECLUTAS 2021-10 Spanish survey (October 2021).

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

Calibración de los parámetros del modelo de directividad de los transductores de la ecosonda Simrad EK60

The scientific echo sounder Simrad EK60 could be used for quantification of fisheries resources in marine science research campaigns. They use different frequency channels (from 18 to 200 KHz), emitted by underwater sound transducers with circular aperture geometries. Calibration is essential to obtain reliable values of Ts (Target Strength) and Sv (Volume Backscattering Coefficient) parameters, which are used to estimate fisheries stocks using echo volume integration. In this paper, manufacturer’s calibration method is presented, together a new proposal for the acquisition and post-processing of calibration data to obtain more accurate results.La ecosonda científica Simrad EK60 se utiliza para cuantificar los recursos pesqueros en campañas de investigación oceanográfica, utilizando diferentes canales de frecuencias (de 18 a 200KHz) mediante transductores acústicos de apertura con geometría circular. Su calibración resulta esencial para obtener los valores de Ts (‘target strength’) y Sv (‘Volume backscattering coefficient’), necesarios para estimar los tamaños de los stocks de las pesquerías mediante integración de los ecos. En este trabajo se presenta el método de calibración propuesto por el fabricante, así como una nueva propuesta de obtención y postproceso de datos que permite obtener calibraciones fiable

Plan acústico municipal de Burriana. Mapas de ruidos y plan de actuación

Consulta en la Biblioteca ETSI Industriales (9093)[ES] El objeto de este estudio es realizar el análisis de los niveles de ruido existentes en el término municipal y proporcionar información acerca de las fuentes sonoras causantes de la contaminación acústica existente. De esta forma se realiza un exhaustivo análisis de la situación acústica actual del municipio, y se proponen una serie de actuaciones que tienen como fin la mejora de la situación y el cumplimiento de los criterios de calidad acústica.Córdoba Sellés, MDP. (2012). Plan acústico municipal de Burriana. Mapas de ruidos y plan de actuación. http://hdl.handle.net/10251/28681.Archivo delegad