The egg production method applied to the spawning biomass estimation of sardine, Sardina pilchardus (Walb.), on the North Atlantic Spanish coast

During April-May 1988, an Egg Production Method Cruise was carried out with the purpose of evaluating the spawning biomass of the sardine, Sardina pilchardus (Walb.), from the Galician and Cantabrian coasts of Spain. This cruise was coordinated with the acoustical evaluation of this stock on board the R/V Cornide de Saavedra. The area covered extends from the Spanish-Portuguese border (41º 55' N) to the Spanish-French border (1º 58' W). Vertical plankton tows at 524 stations were distributed over the continental shelf and slope water in a 6 X 6 mile grid, with a 6 X 3 mile grid in areas of more intense spawning, to estimate the daily egg production parameter. A total of 44 epipelagic trawls were done in order to estimate the biological parameter relative to the adult population, that is, average female weight, batch fecundity, spawning fraction and sex ratio. The suruey area was post-stratified into three regions and the spawning biomass was estimated for each region. The sum of the three spawning biomass estimates was the total spawning biomass for the survey area. Three regions were established by differentiated adult parameters, such as average female weight in conjunction with the considered acoustical divisions. These regions correspond to the Galician coast (I), the western Cantabrian area (II) and the eastern sector of the Cantabrian coast (III).Desde abril a mayo de 1988 se aplica el Método de Producción Diaria de Huevos con el objetivo de estimar la biomasa reproductora de la sardina noratlántica española, Sardina pilchardus (Walb.), comprendida en el área de las costas de Calicia y del Cantábrico. Esta campaña fue realizada coordinadamente con la campaña de evaluación acústica de pelágicos a bordo del B/O Comide de Saavedra. El área de cobertura se extiende desde la frontera luso-española (41º 55' N) hasta la frontera con Francia (1º 58' O). Se muestrearon 524 estaciones para la recogida de muestras planctónicas a lo largo de la plataforma y talud en un mallaje de estaciones de 6 X 6 millas náuticas, y en zonas de mayor abundancia de huevos en 6 X 3, con el propósito de estimar la producción diaria de huevos de sardina. Se llevaron a cabo un total de 44 pescas epipelágicas con el fin de estimar los parámetros biológicos y reproductivos de la población de adultos, como son el peso medio de las hembras, fecundidad parcial, fracción de hembras en puesta y proporción de sexos. El área muestreada fue post-estratificada en tres regiones y, consiguientemente, la biomasa reproductora estimada para cada una de las mismas. La biomasa reproductora total se logra con la suma de cada una de las biomasas por región. El criterio de estratificación por regiones se basa en la diferenciación zonal de los parámetros de adultos, como es el peso medio de las hembras, coincidiendo con las divisiones acústicas preestablecidas. Estas regiones corresponden a las costas de Galicia (I), Cantábrico occidental (II) y Cantábrico oriental (III).Versión del editor0,000

Results of sardine daily egg production off the northern coast of Spain for April 2008.

This document presents the results of the SAREVA0408 ichthyoplankton survey conducted by IEO (Instituto Español de Oceanografía). This survey was carried out on board R/V Cornide de Saavedra during April 2008. The covered area was the North and North-western Iberian Peninsula waters and the inner part of the Bay of Biscay (from 42°N to 45°N).The present paper includes data on sardine (Sardina pilchardus) egg distribution and abundance from the SAREVA0408 survey, as well as the estimation of daily egg production (DEPM) for sardine in the North Spanish Atlantic, Cantabrian waters and south of the Bay of Biscay

Preliminary results of sardine daily egg production off the northern coast of Spain in April 2008.

This document presents the results of the SAREVA0408 ichthyoplankton survey conducted by IEO (Instituto Español de Oceanografía). This survey was carried out on board R/V Cornide de Saavedra for April 2008. The covered area was the North and North-western Iberian Peninsula waters and the inner part of the Bay of Biscay (from 42°N to 45°N).The present paper includes data on sardine (Sardina pilchardus) egg distribution and abundance from the SAREVA0408 survey, as well as the estimation of daily egg production (DEPM) for sardine in the north Spanish Atlantic, Cantabrian waters and south of the Bay of Biscay

Characterising the spawning habitats of sardine from the northern coast of Spain in april 2008

This document presents the results of the analysis from sardine (Sardina pilchardus) egg densities in relation to environmental (temperature, salinity) and geographic (longitude, depth) variables. Data were obtained from the SAREVA0408 ichthyoplankton survey conducted by IEO (Instituto Español de Oceanografía) in April 2008. Quotient analysis, temperature-salinity plots and time distribution for eggs per stage of development, were employed to study spawning habitat of the sardine off north Spanish Atlantic, Cantabrian waters and south of the Bay of Biscay

DEPM 2014. Preliminary Egg Results for the Atlanto-Iberian Sardine ICES VIII and IXa

The triennial DEPM for estimation of sardine spawning biomass for the Atlanto-Iberian stock areas IXa – VIIIc and VIIIb up to 45 º N took place in the S and W (IPMA) from 15th March to 26th April and in the N (Galicia, Cantabrian Sea and French coast, IEO) between 29th March and 21st April. The whole area was surveyed however the Portuguese survey occurred much later than usual and suffered several interruptions; part of IPMA´s DEPM survey was conducted simultaneously to the acoustics survey onboard the same vessel. The number of fishing samples was maintained at levels similar to other years but it was evident that sardine schools were less available than during previous surveys in particular in the western and northern shores. Preliminary estimates highlighted a sharp decrease in egg production from 2011 to 2014; this pattern was particularly clear in the northern stratum