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International Council for the Exploration of the Sea (ICES) - North Pacific Marine Science Organization (PICES) International symposium : Drivers of dynamics of small pelagic fish resources, 6-11 March 2017, Victoria, BC, Canada, In the Mediterranean Sea, European sardine (Sardina pilchardus) is an important species in terms of biomass and catches, although recent declines have been observed, in addition to negative changes in body condition. The objective of this study was to better understand how sardine respond to environmental changes in the western Mediterranean Sea. We implemented a size-structured bioenergetics model based on Dynamic Energy Budget (DEB) theory. DEB models allow the description of the energy allocation in various physiological processes during organisms¿ full life-cycle (growth, maintenance, and maturity/reproduction from egg to adult). To calibrate the model biometric data collected from 2009 to 2015 and energy density estimates from calorimetry analysis were used. Model simulations captured ontogenetic growth patterns and energy storage in spring and summer previous to the spawning season. To examine population dynamics, the DEB model was coupled to an individualbased population model. Scenarios of increasing sea surface temperature (SST) and reduction of food availability (FA) were tested. Stock productivity of sardine was affected through reductions of individual growth rates with decreasing FA, as well as reductions in fecundity rates due to a shorter spawning window as a consequence of an increase of SST in the study area. This information will be vital in assisting the management plans of sardines in the Mediterranean marine ecosystems in the near future

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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.

40th CIESM Congress: The largest Forum on Mediterranean and Black Sea Research, 28 October - 1 November 2013, Marseille, France.-- 1 page, 1 figure, In the present study the biomass and numerical contribution of micronekton organisms responsible of the night Scattering Layers of the upper water column were investigated. Relative abundance in weight and number of individuals of the different groups collected using midwater trawls performed concurrently with the detection of the scattering layers by echosounders are presented

We investigate the effect of strong meteorological perturbations in early spring on the success of mackerel (Scomber scombrus) recruitment in the N⁄NW Iberian area (southern Bay of Biscay) for the period 1999–2008. In 2000, the year of the most pronounced recruitment failure on record, two consecutive multidisciplinary surveys sampled hydrographic conditions and mackerel eggs, larvae and post-larvae over the main mackerel spawning grounds of the north and northwest coast of the Iberian Peninsula. Analysis of egg and larval abundance and birthdates based on the otoliths of mackerel juveniles caught between July and October 2000 showed that there were no survivors from the early spring spawns, indicating a massive loss of early spawning effort. Moreover, the abundance of 1-year-old mackerel estimated from an acoustic survey carried out in 2001 was the lowest observed within the 1999–2008 time series. This low or null survival from the early spawns in 2000 could be due to the meteorological and oceanographic conditions of that spring, in particular two storm events in April after a relatively calm March. The first storm event from the north caused strong local wind in the southern Bay of Biscay but a weak oceanographic response. The second storm event from the southwest was mainly felt west of Galicia and caused a notable increase in shelf currents and a shift of the hydrographical structure along the shelf. Detailed analysis of strong wind pulses in early spring within the historical recruitment record suggests that strong local turbulence generated by high wind speeds and advection of larvae caused by the enhancement of shelf currents can contribute to reduced recruitment. Our observations indicate that, in 2000, both mechanisms were present, Sí

RNA and DNA content of seabass (Dicentrarchus labra.x) larvae were determined from day 10 to day 60 after hatching in an aquaculture facility. Our results show a two-phase modulation of the RNA/DNA ratio throughout seabass larvae development. From day 10 after hatching there is an increase in the RNA/DNA ratio reaching maximal values at day 30 of age. Then, the RNA/DNA ratio decreased reaching minimal values at day 60 after hatching. These results are consistent with a high rate of protein synthesis during the first 30 days of seabass development compared with the rest of the developmental period studied. The results are compared with that of otolith growth carried out for the same species larvae, APROXIMACIÓ A LA DETERMINACIÓ DE LA VARIABILITAT DE LA RELACIÓ DNA/RNA DURANT EL DESENVOLUPAMENT LARVAL DEL LLOBARRO Dicentrarchus labrax. S'ha determinat el contingut de DNA (àcid desoxiribonucleic) i de RNA (àcid ribonucleic) en larves de llobarro (Dicentrarchus labrax) d'edats compreses entre 10 i 60 dies de vida, procedents d'una planta de cultiu. Els resultats obtinguts mostren dues fases diferenciades de desenvolupament d'aquestes larves, basades en la relaci6 RNA/DNA avaluada. S'observa un augment de la proporci6 de RNNDNA des del dia 10 fins el dia 30 de vida, per a decréixer a continuació, trobant els valors mínims en les larves de 60 dies de vida, Sí

La pesca artesanal en Mallorca ha constituido desde antiguo una importante actividad humana. De las 273 embarcaciones de pesca existentes en la isla en el año 1872, 241 correspondían a la flota de artes menores. En la actualidad, la flota artesanal de Mallorca está compuesta por el 83 % de los barcos de la flota pesquera de la isla (n = 383), con un tonelaje total de 1397 trb y una potencia total de 15.280 caballos de vapor. La pesquería que desarrollan es multiespecífica, explotando especies de alto valor comercial consumidas en su mayor parte en el mercado local. Las pesquerías más importantes para esta flota son las de jonquillo Aphia minuta (Risso, 1810), de diciembre a marzo; sepia Sepia ojficina/is (Linnaeus, 1758), de febrero a mayo; langosta roja Palinurus elephas (Fabricius, 1787), de marzo a agosto, y llampuga Coryphaena hippurus (Linnaeus, 1758), de agosto a diciembre. Estas pesquerías se caracterizan por su estacionalidad y por requerir el uso de artes específicos y variaciones en la actividad de la flota. La pesca de jonquillo va dirigida al góbido Aphia minuta, que suele ir acompañado en pequeña proporción por especies de góbidos afines como Pseudaphia ferreri (De Buén y Fage, 1908) y Cristallogobius linearis (Von Düben, 1845). La denominación de jonquillo es puramente comercial y se utiliza cuando la especie dominante (más del 80 %) es el A. minuta. Estas especies, agrupadas en la subfamilia Sycidiaphinae, se diferencian del tipo general, definido como subfamilia Gobiinae, por el hecho de conservar durante toda su vida, muy breve y nunca superior al año, caracteres juveniles como el tamaño reducido de los adultos (no superan los 50 mm de talla en esta zona), la adaptación a la vida planctónica (salvo para la reproducción) y la transparencia del cuerpo. [Ver Resumen completo en pdf]., Artisanal fishing has been an important activity in Majorca since ancient times. Of the 273 fishing boats based in Majorca in 1872, 241 corresponded to the small-scale fleet. At the present time, 83 % of the boats from the island's fishing fleet (n = 383) correspond to the Majorcan artisanal fleet, with a total tonnage of 1.397 GRT and a total power of 15.280 h.p. They work in a multispecific fishery, exploiting species of high commercial value that are consumed largely on the local market. The most important fisheries for this fleet are those directed at jonquillo, or transparent goby Aphia minuta (Risso, 1810), from December to March; cuttlefish Sepia officinalis (Linnaeus, 1758) from February to May; common spiny lobster Palinurus elephas (Fabricius, 1787) from March to August and dolphinfish Coryphaena hippurus (Linnaeus, 1758) from August to December. These fisheries are characterised by their seasonality and the requirement to use specific methods for each one, thus varying the fleet's activities. Jonquillo fishing is aimed at the goby Aphia minuta, which is usually accompanied by species of similar gobies, such as Pseudaphia ferreri (De Buén y Fage, 1908) and Cristallogobius linearis (Von Düben, 1845). The name jonquillo is purely commercial and is used when the dominant species (more than 80 %) is A. minuta. These species, grouped in the Sycidiaphinae subfamily, are differentiated from the common type, defined as the Gobiinae subfamily, by the fact that they maintain juvenile characters (neotenics) —such as the reduced size of the adults (not greater than 50 mm in this zone), adaptation to a planktonic life (except for reproduction) and a transparent body— during their whole life, which is very short, never more than a year. [See full Summary pdf]., Instituto Español de Oceanografía, SI

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Se presentan los resultados de la Campaña de Evaluación Acústica ECOMED 91 realizada sobre la plataforma continental del Mediterráneo español y la parte occidental del Golfo de León, entre el 21 de octubre y el 21 de noviembre de 1991. Las biomasas estimadas han sido de 252.423 t de sardina (Sardina pilchardus) y 31.683 t de boquerón (Engraulis encrasicolus). Estas cifras, comparadas con las obtenidas en la campaña del año anterior en la misma época del año y con la misma metodología, indican un aumento de la biomasa total de la sardina en el área, debido a la importancia del último reclutamiento y una disminución de la correspondiente al boquerón, Results on the Acoustic estimates of pelagic stocks through the survey ECOMED 91 are presented. It covered the continental shelf of the Mediterranean spanish coasts and the western area off the Gulf of Lyons from October 21 to November 21, 1991. The biomass estimates were: 252.423 t of sardine (S. pilchardus) and 31.683 t of anchovy (E. encrasicolus). These values in comparison with those estimated last year, in the same season and same methodology, indicate an increase in sardine total biomass in the area due to the importance of the last recruitment and a decrease of anchovy

The Working Group on Acoustic and Egg Surveys (WGACEGG) coordinates the pelagic integrated surveys in ICES Areas 7, 8 and 9. Those surveys provide fisheries-independent, acoustic and/or egg-based estimates of the biomass and demographic structure of sardine and anchovy populations. Survey biomass estimates are the main inputs used to manage those commercially important small pelagic stocks in the European Atlantic area (EAA). Taking advantage of the fine spatial resolution of acoustic and egg data, and of ancillary ecosystem data provided by integrated pelagic surveys, WGACEGG also compile standard gridded maps of anchovy and sardine eggs and adult biomass, as well as maps of key in-situ hydrological parameters (surface salinity and temperature). We present an overview of the survey products provided by WGACEGG since 2003. Examples of combination of series of maps are provided to showcase how to assess anchovy and sardine habitats along the strong latitudinal gradient characterising the EAA.