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

Angelico, M.M. (Maria Manuel)

Díaz-Conde, M.P. (María Paz)

Franco-Fernández, C. (Concha)

Lago-de-Lanzós-y-Tomás, A. (Ana)

Nunes, C. (Cristina)

Pérez-Pérez, J.R. (José Ramón)

English

Angélico, María Manuel

Díaz-Conde, María Paz

Franco-Fernández, Concha

Lago-de-Lanzós-y-Tomás, Ana

Nunes, Cristina

Pérez-Pérez, José Ramón

Digital.CSIC

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

Angélico, M.M. (María Manuel)

Repositorio Institucional Digital del IEO

 1 Working Document to be presented to the WGHANSA, Copenhagen, 20-25 June 2014   DEPM  2014 Preliminary Egg Results for the Atlanto-Iberian Sardine ICES VIII and IXa    Maria Manuel Angélico2, Paz Díaz1, Concha Franco1, Ana Lago de Lanzós1, Cristina Nunes2, Jose Ramón Pérez1.  1Instituto Español de Oceanografía, Centros Oceanográficos de Vigo y Madrid.  2Instituto Portugués do Mar e da Atmosfera – IPMA, Lisboa   This document provides the preliminary egg parameter results from the 2014 sardine DEPM (IPMA + IEO). This survey will be reported to WGACEGG in November 2014.  1. Summary  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.  2. Background The DEPM for estimation of sardine spawning biomass within the Atlanto-Iberian stock area is conducted every three years by IPMA (Instituto Português do Mar e da Atmosfera, Portugal) and IEO (Instituto Español de Oceanografía, Spain) in an internationally coordinated survey. The Portuguese survey covers the Atlantic waters from the entrance of the Strait of Gibraltar to the northern border of Portugal in January/February, while the Spanish survey takes place in March/April in the northern area, from the Portuguese/Galician border to the south of the Armorican shelf, in French waters. In 2014, the Portuguese survey (PT-DEPM14-PIL) took place exceptionally late in the reproductive season (off peak) due to technical constraints with the research vessel (RV Noruega); moreover it was interrupted in several occasions owing to adverse weather conditions and additional logistical issues. The region north of Lisbon was surveyed during the second half of March (15-21), the survey was then interrupted only to be resumed on the 4th of April; by this  2 time together with the acoustics survey (PELAGO14) and restarting from south. During the period from 4th April to 13th May both surveys were carried out concurrently; the night period was used for plankton sampling while during light hours the acoustics surveying took place; adult sampling was directed at both surveys. Plankton surveying was repeated in the area north of Lisbon during the acoustics coverage in the region (1-13 May); the egg results available at present do not include the second coverage of the northern area. The Spanish DEPM survey (SAREVA0414) was undertaken using two vessels; RV Vizconde de Eza , for plankton sampling mainly, from the 28th March to the 21th of April, and RV Miguel Oliver to obtain adult samples which were collected during the acoustics survey (PELACUS0414) from 26 March to 22 April. In 2014 IEO´s survey took place on board RV Vizconde de Eza (mostly for plankton surveying) instead of RV Cornide de Saavedra which was used from 1988 to 2011.   3. Analyses methodology  All calculations for area delimitation, egg ageing and model fitting for egg production (P0) estimation were carried out using the R packages (geofun, eggsplore and shachar) available at ichthyoanalysis (http://sourceforge.net/projects/ichthyoanalysis). The model of egg development with temperature was derived from the incubation experiment data available within the sardata, R library. Egg ageing was achieved by a multinomial Bayesian approach described by Bernal et al (2008); a normal probability distribution was used with peak spawning assumed to be at 21:00h with 3h standard deviation. The exponential model: E [P] = P0 e -Z age was fitted by Generalized Linear Model (GLM), with a negative binomial function.  Strata definition (Figure 1): Stratum 1- South (IXa South): Strait of Gibraltar to Cape S. Vicente, Stratum 2 - West (IXa West)- Cape S. Vicente to northern limit between Portugal and Spain;  Stratum 3 -North (IXa North + VIIIc)- from the Portuguese-Spanish border to the Spanish-French Atlantic limit.   The stratum furthest north, in French waters (sub-area of VIIIb up to 45ºN) was analysed separately.   4. Results  The surveys, in areas VIIIc and IXa, covered a total area of 80830 km2 of which 22467 km2 were considered the spawning area (Figures 1 to 3). In total 793 PairoVET samples were obtained (Table 1). Sardine egg distribution, derived from the PairoVET system, for the whole area is presented in Figure 3. The percentage of stations in the whole area with sardine eggs was 26.0% (S: 41.8%, W: 31.7%, N: 16.7%).  In total, 2406 sardine eggs were collected by one of the paired PairoVET nets per survey. The egg numbers obtained in the south and west were comparable to 2011 but were much lower in the north. Measured SST ranged from 12.3 to  3 19.9ºC. Temperature distribution followed the common patterns; the highest temperature values were observed in the southern area and the lowest values registered for the Cantabrian Sea.  The higher temperatures recorded in the south were likely due to the period of surveying later than usual, already after the onset of spring.  The winter/spring atmospheric conditions in the Atlanto-Iberian region during the first quarter of 2014 were very unstable with episodes of heavy rain and strong wind events, this background led to a highly variable hydrodynamic setting with agitated shelf waters for quite long periods.   The egg production model selected includes independent egg production for the three strata and a common mortality (same model selected for the 2012 series revision, ICES 2012). It was not possible to estimate mortality per strata as the value for the western stratum was non-coherent (Table 2, Figure 4).   summary : • Portuguese survey conducted much later than usual (and with interruptions); consequently preventing solid comparisons of the 2014 results with the historic series  • spawning area in 2014 for the whole area slightly reduced compared to 2011 and the smallest of the historic series; patchy egg distribution • spawning area reduction particularly evident in the north (around 40% of the total spawning area in 2011) while in the west it increased to almost the double • the southern and western regions showed similar daily egg production per m2 (eggs/m2/day) which was much larger than in the north; for all strata daily egg production per m2 was much lower than in recent surveys • sum of total egg production for the 3 strata in 2014 much lower than in 2011, in particular in the northern and southern regions, similar in the west  (Table 2 and Figure 5) • mortality value (single mortality for whole area) similar to 2005 and one of the lowest of the series but with high CV • to note that these are preliminary estimates; the complete set of data will be available before the WGACEGG meeting and the analyses repeated and further discussed   • during the 2014 survey the availability of adult sardine for trawling was limited in the whole area; nevertheless 36 samples were obtained, 11 in the south, 10 in the west and 15 in the north; extra samples (14) from purse-seiners were collect in Portugal • the number of hydrated females collected was higher than in 2011 • no estimates are available at present for the adults parameters     4 sub-region VIIIb (french waters)  • 128 PairoVET samples taken in French waters in area VIIIb; 60% with eggs • high egg densities were observed in the area furthest north; the large majority of the sardine eggs observed during the IEO survey (1449 in a total of  1765; 82%) were collected in the sub-region VIIIb  • spawning area in 2014 reduced  to 7914 km2 compared to 2011 survey  (12400 km2)   • daily egg production per m2 in 2014 (212)  similar to 2011  survey and much larger than in previous surveys • total egg production (eggs/day) in 2014 lower than in 2011, 1.67 compared to 2.72 respectively • daily egg production per m2 and total egg production (eggs/day) much higher than in the adjacent stratum, in Cantabrian waters (IXa North + VIIIc)    -------------------------------------------------------------------------------------------------------------- GLM model adjustment:  Call: glm.nb(formula = cohort ~ offset(log(Efarea)) - 1 + Stratum +      age, data = aged.data, weights = Rel.area, init.theta = 0.292046895523314,      link = log)  Deviance Residuals:       Min        1Q    Median        3Q       Max   -1.68744  -1.04106  -0.73700   0.02468   3.27516    Coefficients:          Estimate Std. Error z value Pr(>|z|)     Stratum1  4.60780    0.27945  16.489   <2e-16 *** Stratum2  4.62316    0.24360  18.978   <2e-16 *** Stratum3  3.63291    0.25887  14.034   <2e-16 *** age      -0.01250    0.00629  -1.988   0.0468 *   --- Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1   (Dispersion parameter for Negative Binomial(0.292) family taken to be 1)      Null deviance: 4367.54  on 521  degrees of freedom Residual deviance:  413.08  on 517  degrees of freedom AIC: 1758.9  Number of Fisher Scoring iterations: 1                 Theta:  0.2920            Std. Err.:  0.0272    2 x log-likelihood:  -1748.9290   ----------------------------------------------------------------------------------------------------     5  References  Bernal, M., Ibaibarriaga, L., Lago de Lanzós, A., Lonergan, M., Hernández, C., Franco, C., Rasines, I., et al. 2008. Using multinomial models to analyze data from sardine egg incubation experiments; a review of advances in fish egg incubation analysis techniques. ICES Journal of Marine Science, 65: 51–59. ICES. 2012. Report of the Working Group on Acoustic and Egg Surveys for Sardine and Anchovy in ICES Areas VIII and IX (WGACEGG), 26-30 November 2012, Fuenguirola, Spain. ICES CM 2012/SSGESST:16. 221 pp. R Development Core Team (2008). R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. ISBN 3-900051-07-0, URL http://www.R-project.org.                            6    Table 1. General egg and adult sampling sardine DEPM 2014.  * acoustics surveying included, not all hauls directed at sardine echotraces     purse-seiners samples not included  Institute IPMA IPMA IEO IPMA/IEO IEO Survey area IXa South IXa West IXa N + VIIIc IXa+VIIIc VIIIb (up to 45º N) SURVEY EGGS      R/V Noruega Noruega Vizconde de Eza  Vizconde de Eza Date 04/04-15/04 15-21/03; 15-26/04 29/03-21/04  09/04-16/04 PairoVET stations 134 265 394 793 128 Positive stations 56 84 66 206 77 Tot. Eggs 1042 1051 316 2406 1449 Max eggs/m2 5900 1620 704 5900 2619 Temp (ºC)  min-max 14.4-19.9 12.8-14.9 12.3-14.9 12.3-19.9 12.3-14.5 Max age (hour) 57.7 59.2 74.2 56.1 74.3 SURVEY ADULTS      Numbers of hauls* 13 31 57 101 13 Positive hauls 11 10 15 36 3     Table 2. Egg parameters from 2014 sardine DEPM survey.     Institute IPMA IPMA IEO IPMA+IEO (total) IEO Parameter/Area IXa South IXa West IXa N + VIIIc IXa+VIIIc VIIIb (up to 45º N) Survey area (Km2) 14558.7 27357.3 38914.4 80830.5 13480.4 Positive area (Km2) 6077.2 8895.7 7494.5 22467.4 7913.8 Z (hour-1) (CV%) -0.012 *(50.3)  -0.021*** (29.2) P0 (eggs/m2/day) (CV%) 100.3  (27.9) 101.8 (24.4) 37.8 (25.9)  211.5 (27.5) P0 tot (eggs/day)(x1012) (CV%) 0.61 (27.9) 0.91 (24.4) 0.28 (25.9) 1.80 (16) 1.67 (27.5)         7                        Figure 1. PaioVET hauls undertaken and spatial strata definition (black- IXa South;  blue – IXa West; red – Ixa North+ VIIIc; green – sub-area of VIIIb).                           Figure 2. Positive area estimated for area VIIIc and IXa ( 22467.4 km2 from a total Iberian Peninsula surveyed area of 80830.5 km2).  -10 -8 -6 -4 -23638404244LongLat 8                                                     Figure 3.  Sardine egg distribution. Egg/m2 from PairoVET sampling (+, egg absence).  The areas indicated refer to the nomenclature used in the text     -11º -10º -9º -8º -7º -6º -5º -4º -3º -2º -1º36º37º38º39º40º41º42º43º44º45º00.1 to 500500.1 to 10001000.1. to 50005000.1 to 5901IXa  SouthIXa  WestIXa NorthVIIIc VIIIb 9                                      Figure 4. Abundance by age of eggs in the different spatial strata (black – south, blue - west stratum, red - north) and fitted mortality curve (single mortality for all strata).                Age (hours)Egg abundance in the samples0 10 20 30 40 50012346820305070 10                                                   Figure 5. Total egg production (eggs/day*1012) by spatial strata (top panel); black – IXa South, blue - IXa West stratum, red – IXa North + VIIIc and for the total stock area off the Iberian Peninsula (bottom panel). Dots and lines indicate the estimates of egg production and their confidence intervals.  0123456789101988 1997 1999 2002 2005 2008 2011 2014P0 (10^12)YearTotal egg production by strataIxa North + VIIIb Ixa West Ixa South02468101214161988 1997 1999 2002 2005 2008 2011 2014P0 (10^12)YearTotal egg production Iberian Peninsula

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

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