This working document presents the results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius) and Norway lobster (Nephrops norvegicus) caught in the Porcupine Spanish Groundfish Survey (SP-PORC-Q3) in 2020. Biomass, abundance, distribution and length frequency were analysed. M. aeglefinus remained low in the study area, although it increased slightly, but M. merlangius grew strongly and reached the highest values in the time series. No signs of recruits for neither two species were found. In addition, the incidental species Pleuronectes platessa and Solea solea were not found in 2020 and Pollachius pollachius has never been caught in the time series. The crustacean N. norvergicus fell sharply this last survey, although the mean individual weight was slightly higher than in previous years since 2016

Baldó, F. (Francisco)

Blanco, M. (Marian)

Fernández-Zapico, O. (Olaya)

Ruiz-Pico, S. (Susana)

Velasco, F. (Francisco)

English

Repositorio Institucional Digital del IEO

  1Working Document to be presented to the Working Group for the Celtic Seas Ecoregion  ICES WGCSE, 5-14 May, 2021. Remote  Results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius) and Norway lobster (Nephrops norvegicus) from the Porcupine Bank Survey (NE Atlantic)  O. Fernández-Zapico1, S. Ruiz-Pico1, M. Blanco1, F. Velasco1 & F. Baldó2    Instituto Español de Oceanografía  (1) (2)   Centro Oceanográfico de Santander Centro Oceanográfico de Cádiz   Promontorio San Martín s/n Muelle de Levante s/n (Puerto Pesquero)  39004 Santander, Spain 11006 Cádiz, Spain      Abstract This working document presents the results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius) and Norway lobster (Nephrops norvegicus) caught in the Porcupine Spanish Groundfish Survey (SP-PORC-Q3) in 2020. Biomass, abundance, distribution and length frequency were analysed. M. aeglefinus remained low in the study area, although it increased slightly, but M. merlangius grew strongly and reached the highest values in the time series. No signs of recruits for neither two species were found. In addition, the incidental species Pleuronectes platessa and Solea solea were not found in 2020 and Pollachius pollachius has never been caught in the time series. The crustacean N. norvergicus fell sharply this last survey, although the mean individual weight was slightly higher than in previous years since 2016.      Introduction The Spanish bottom trawl survey on the Porcupine Bank (ICES Divisions 7c and 7k) has been carried out annually in the third-quarter (September) since 2001 to study the distribution, relative abundance and biological parameters of commercial fish in the area (ICES, 2017).  The aim of this working document is to update the results (biomass and abundance indices, length frequency and geographic distributions) of the species Melanogrammus aeglefinus (haddock), Merlangius merlangius (whiting) and Nephrops norvegicus (Norway lobster) on the Porcupine bottom trawl surveys after the results presented previously (Ruiz-Pico et al 2018, 2019, 2020).  Material and methods The Spanish Ground Fish Survey on the Porcupine bank (SP-PORC-Q3) has been carried out annually since 2001 on board the R/V “Vizconde de Eza”, a stern trawler of 53 m and 1800 Kw. The area covered extends from longitude 12° W to 15° W and from latitude 51° N to 54° N, following the standard methodology for the IBTS North Eastern Atlantic surveys (ICES, 2017). The sampling design was random stratified to the area (Velasco and Serrano, 2003) with two   2geographical sectors (Northern and Southern) and three depth strata (<300 m, 300-450 m and 450-800 m) (Figure 1). Hauls allocation is proportional to the strata area following a buffered random sampling procedure (as proposed by Kingsley et al., 2004) to avoid the selection of adjacent 5×5 nm rectangles. More details on the survey design and methodology are presented in ICES (2017).  The reduction in the tow duration (20 instead of 30 minutes) has been applied since 2016 to reduce the catches. The biomass indices of the entire time series are not affected by this reduction as the samples are still representative. The results are extrapolated to 30 minutes of trawling time to maintain the consistency of the time series.   Results and discussion Despite the problems created by the pandemic and the COVID-19 disruption, Porcupine Groundfish Survey was carried out without major problems, apart from an initial 9-day delay that did not affect the overall survey duration. In 2020, 81 valid standard hauls and 10 additional hauls were carried out. Among the additional hauls, three of them have been carried out into the standard stratification, to improve coverage in the gaps left by random sampling and seven of them, between 839 and 1425 m, to explore the continuity of the fish community in Porcupine Seabight (Figure 1).    The total stratified catch per haul increased significantly in 2020 compared to the previous year, becoming the second highest catch in the historical series below the year 2015 (Figure 2). Fish represented 96% of the total catch and the species analyzed in this report represented only a small percentage of the total fish catch: haddock (0.3%) and whiting (0.05%). However, Norway lobster represented 6% of the total crustacean catch.  In 2020, the biomass and abundance of these two fishes increased compared to the previous year, slightly for M. aeglefinus, remaining quite low values in the time series, but it did strongly for M. merlangius, reaching the highest values in the time series, both in biomass and abundance terms. No signs of recruits for neither two species were found. In addition, the abundance of specimens around 30 cm of both species also increased, specially for M. merlangius. The biomass and abundance of the crustacean N. norvergicus fell sharply in this last survey and it did for all the groups of sizes: adults (> 26 mm), juveniles (21-26 mm) and recruits (< 21 mm), although  the mean individual weight was slightly higher than in previous years since 2016. Melanogrammus aeglefinus (haddock) In 2020 this species increased slightly both in terms of biomass and abundance and, although the biomass recovered mean values of the historical series, the abundance value remained among the lower values of the time series after the peak in 2013 (Figure 3). M. aeglefinus was distributed on the Irish shelf, as usual, and a few spots of biomass were found in the south and in the west of the bank (Figure 4). After the high recruitments in 2016 and 2017, small specimens (< 20 cm) have been decreasing in the last two years and no individuals below 26 cm were found in this last survey (Figure 5, Figure 6 and Figure 7).  Merlangius merlangius (whiting) Biomass of M. merlangius has increased six times the value of the previous year and abundance has raised almost five times. Both biomass and abundance of this species have reached the highest values of the historical series after the strong increase in 2020 (Figure 8).   3All the specimens were found in two hauls around 200 m depth, in the Irish shelf (Figure 9). They ranged from 24 to 48 cm, but the most abundant sizes were around 34 cm (Figure 10).   Nephrops norvegicus (Norway lobster) In 2020, the downward trend in biomass and abundance of this species continued from the peak of 2018, but in this last survey it fell sharply, dividing the biomass value in more than a half compared to the previous year and also the abundance value by around a third (Figure 11). The muddy slope of the Porcupine Seabight is where both adults and recruits of N. norvegicus dwell. Nephrops remained concentrated in and around the closed area. In 2020, 9 positive catches, representing 61% of the total biomass, were found in the closed area and 17 out and around the area, representing 32%. Only 7% of the biomass was found in 15 hauls in the rest of the study area (Figure 12 and Figure 13). Fewer specimens were found in 2020, fewer recruits (< 21 mm), juveniles (21-26 mm) and adults (> 26mm) (Figure 14). However, the mean individual weight was slightly higher than in previous years since 2016 (around 34g) (Figure 15). Recruits were concentrated mainly in the northern part of the closed area as usual (Figure 16). The length distribution (Figure 17) showed a predominance of adults around 32 mm in this last survey, similarly to the previous three years, although in less abundance.  Acknowledgements		We would like to thank the R/V Vizconde de Eza crew and the IEO scientific team that made the Porcupine Spanish Groundfish Survey possible. They are included in the ERDEM5 project, which has been co-funded by the EU through the European Maritime and Fisheries Fund (EMFF) within the National Program of collection, management and use of data in the fisheries sector and support for scientific advice regarding the Common Fisheries Policy.  References  ICES, 2017. Manual of the IBTS North Eastern Atlantic Surveys. Series of ICES Survey Protocols SISP 15. 92 pp. http://doi.org/10.17895/ices.pub.35 Kingsley, M.C.S.; Kanneworff, P. and Carlsson, D.M., 2004. Buffered random sampling: a sequential inhibited spatial point process applied to sampling in a trawl survey for northern shrimp Pandalus borealis in West Greenland waters. ICES Journal of Marine Science, 61: 12-24. Ruiz-Pico, S., Fernández-Zapico, O., Blanco, M., Velasco, F., Baldó, F. 2020. Results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius) and Norway lobster (Nephrops norvegicus) from the Porcupine Bank Survey (NE Atlantic). Working Document presented to ICES WGCSE 2020. 17 pp. Ruiz-Pico, S., Blanco, M., Fernández-Zapico, O., Velasco, F., Baldó, F. 2019. Results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius) and Norway lobster (Nephrops norvegicus) from the Porcupine Bank Survey (NE Atlantic). Working Document presented to ICES WGCSE 2019. 16 pp. Ruiz-Pico, S., Blanco, M., Fernández-Zapico, O., Velasco, F., Baldó, F. 2018. Results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius), cod (Gadus morhua) and Norway lobster (Nephrops norvegicus) from the Porcupine Bank Survey (NE Atlantic). Working Document presented to ICES WGCSE 2018. 19 pp. Velasco, F. and Serrano, A., 2003. Distribution patterns of bottom trawl faunal assemblages in Porcupine Bank: implications for Porcupine surveys stratification design. WD presented to the ICES IBTSWG, Lorient, France 25-28 March 2003. 19 pp.   4Velasco, F.; Baldó, F. & González Herraiz, I. 2018. Reporto n Nephrops results from Porcupine Bank 2018 bottom Trawl Survey. WD presented to the ICES ADGNEPH, ICES HQ, Copenhagen, Oct. 2018. 5 pp.    5Figures GalwayIRELANDSector 1: E, F & GSector 2: F & G15º 14º 13º 12º 11º 10º 9º51º52º53º54º15º 14º 13º 12º 11º 10º 9º51º52º53º54º15W 14W 13W 12W 11W15W 14W 13W 12W 11W51N52N53N54N51N52N53N54NValid towsExtra tows Figure 1. Left: Stratification design used in Porcupine surveys from 2003, previous data were re-stratified. Depth strata are: E) shallower than 300 m, F) 301 – 450 m and G) 451 – 800 m. Grey area in the middle of Porcupine bank corresponds to a large non-trawlable area not considered for area measurements and stratification. Right: hauls performed in 2020  Yearkghaul10500100015002001200220032004200520062007200820092010201120122013201420152016201720182019202010 %90 % Figure 2. Evolution of the total catch in Porcupine surveys (2001-2020)   6Yearkghaul1Biomass051015202001200220032004200520062007200820092010201120122013201420152016201720182019202010 %90 %YearIndhaul1Number0204060802001200220032004200520062007200820092010201120122013201420152016201720182019202010 %90 % Figure 3. Evolution of Melanogrammus aeglefinus biomass and abundance indices in Porcupine surveys (2001-2020). Boxes mark parametric standard error of the stratified abundance index. Lines mark bootstrap confidence intervals (α = 0.80, bootstrap iterations = 1000) 51525354200 kg2011200 kg2012200 kg2013200 kg2014200 kg20155152535415 14 13 12 11200 kg201615 14 13 12 11200 kg201715 14 13 12 11200 kg201815 14 13 12 11200 kg201915 14 13 12 11200 kg2020 Figure 4. Geographic distribution of Melanogrammus aeglefinus catches (kg×30 min haul-1) in Porcupine surveys (2011-2020)   7  Length (cm)Indhaul10.51.01.520110.51.01.520120.51.01.520130.51.01.520140.51.01.520150.51.01.520160.51.01.520170.51.01.520180.51.01.520190.51.01.55 10 15 20 25 30 35 40 45 50 55 60 65 70 75 802020 Figure 5. Mean stratified length distributions of Melanogrammus aeglefinus in Porcupine surveys (2011-2020)    820012002200320042005200620072008200920102011201220132014201520162017201820192020Indhaul105101520253035Melanogrammus aeglefinus1 - 20 cm Figure 6. Mean stratified abundance of Melanogrammus aeglefinus recruits (< 20 cm) in Porcupine surveys (2001-2020)     M elanogrammus aeglefinus <20 cm  20 cm5152535415 14 13 12 1140 kg200215 14 13 12 1140 kg200715 14 13 12 1140 kg201615 14 13 12 1140 kg201715 14 13 12 1140 kg201915 14 13 12 112020 Figure 7. Geographic distribution of Melanogrammus aeglefinus recruits (< 20 cm) in Porcupine surveys   9Yearkghaul1Biomass0.00.20.40.60.81.01.22001200220032004200520062007200820092010201120122013201420152016201720182019202010 %90 %YearIndhaul1Number012342001200220032004200520062007200820092010201120122013201420152016201720182019202010 %90 % Figure 8. Evolution of Merlangius merlangus biomass and abundance indices in Porcupine surveys (2001-2020). Boxes mark parametric standard error of the stratified abundance index. Lines mark bootstrap confidence intervals (α = 0.80, bootstrap iterations = 1000)  5152535440 kg201140 kg201240 kg201340 kg201440 kg20155152535415 14 13 12 1140 kg201615 14 13 12 1140 kg201715 14 13 12 1140 kg201815 14 13 12 1140 kg201915 14 13 12 1140 kg2020 Figure 9. Geographic distribution of Merlangius merlangus catches (kg×30 min haul-1) in Porcupine surveys (2011-2020)   10Length (cm)Indhaul10.050.150.2520110.050.150.2520120.050.150.2520130.050.150.2520140.050.150.2520150.050.150.2520160.050.150.2520170.050.150.2520180.050.150.2520190.050.150.255 10 15 20 25 30 35 40 45 50 55 602020 Figure 10. Mean stratified length distribution of Merlangius merlangus in Porcupine surveys (2011-2020)   11Yearkghaul1Biomass012342001200220032004200520062007200820092010201120122013201420152016201720182019202010 %90 %YearIndhaul1Number0501001502001200220032004200520062007200820092010201120122013201420152016201720182019202010 %90 % Figure 11. Evolution of Nephrops norvegicus biomass and abundance indices in Porcupine surveys (2001-2020). Boxes mark parametric standard error of the stratified abundance index. Lines mark bootstrap confidence intervals (α = 0.80, bootstrap iterations = 1000)  5152535440 kg201140 kg201240 kg201340 kg201440 kg20155152535415 14 13 12 1140 kg201615 14 13 12 1140 kg201715 14 13 12 1140 kg201815 14 13 12 1140 kg201915 14 13 12 1140 kg2020 Figure 12. Geographic distribution of Nephrops norvegicus catches (kg×30 min haul-1) in Porcupine surveys (2011-2020)   12 15W 14W 13W 12W 11W15W 14W 13W 12W 11W51N52N53N54N51N52N53N54NNephrops norvegicusa)Weight in kgsx5 10 20Outside Inside02468kg * haul 1Nephrops catchesb) Figure 13. a) Nephrops norvegicus catches in Porcupine survey 2020 showing hauls performed inside and outside the area closed to trawl (red line). b) boxplot showing the differences in catches inside an outside the closed area (only hauls with Nephrops catches are considered)   20012002200320042005200620072008200920102011201220132014201520162017201820192020Indhaul10.00.51.01.52.0Small NephropsSurvey< 21 mma)20012002200320042005200620072008200920102011201220132014201520162017201820192020Indhaul1051015Juvenile NephropsSurvey21-26 mmb)20012002200320042005200620072008200920102011201220132014201520162017201820192020Indhaul1020406080100Adult Nephrops>26 mmSurveyc) Figure 14. Abundance of small Nephrops (<21 mm), juveniles between 21-26 mm and adults (>26 mm) in Porcupine survey 2001-2020     13Years(g)2001 2003 2005 2007 2009 2011 2013 2015 2017 2019020406080 Figure 15. Mean individual weight in Porcupine survey 2001-2020  Nephrops norvegicus <21 cm5152535440 ind.201140 ind.201240 ind.201340 ind.201440 ind.20155152535415 14 13 12 1140 ind.201615 14 13 12 1140 ind.201715 14 13 12 1140 ind.201815 14 13 12 1140 ind.201915 14 13 12 1140 ind.2020 Figure 16. Geographic distribution of Nephrops norvegicus recruits (< 21 mm) in Porcupine surveys (2011-2020)      14Length (mm)Indhaul124620132462014246201524620162462017246201824620192465 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 902020Male Female UndetLength ()density0.000.020.040.060.0820130.000.020.040.060.0820140.000.020.040.060.0820150.000.020.040.060.0820160.000.020.040.060.0820170.000.020.040.060.0820180.000.020.040.060.0820190.000.020.040.060.0810 20 30 40 50 60 70 80 902020 Figure 17. Mean stratified length distributions and length density plots of Nephrops norvegicus in Porcupine surveys (2013-2020)      

Results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius) and Norway lobster (Nephrops norvegicus) from the Porcupine Bank Survey (NE Atlantic)

Working Document presented to the Working Group for the Celtic Seas Ecoregion (ICES WGCSE), 4 - 13 May 2022, Ghent, Belgium.This working document presents the results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius) and Norway lobster (Nephrops norvegicus) caught in the Porcupine Spanish Groundfish Survey (SP-PORC-Q3) in 2021. Biomass, abundance, distribution and length frequency were analysed. The biomass of these two fishes decreased compared to the previous year. Signs of recruits were found for both species, especially for M. aeglefinus. In addition, the incidental species Pleuronectes platessa and Solea solea were not found in 2021 and Pollachius pollachius has never been caught in the time series. The crustacean N. norvergicus has increased slightly in this last survey and has done so for all the groups of sizes, thought more markedly in those larger than 21 mm. However, the mean individual weight was slightly lower than in previous years.Fondo Europeo Marítimo y de Pesca.N

Fernández-Zapico, Olaya

Blanco, Marian

Ruiz-Pico, Susana

Velasco, Francisco

Baldó, Francisco

Digital.CSIC

Results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius) and Norway lobster (Nephrops norvegicus) from the 2021 Porcupine Bank Survey (NE Atlantic)

Results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangus) and Norway lobster (Nephrops norvegicus) from the Porcupine bank Survey (NE Atlantic)

This working document presents the results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius) and Norway lobster (Nephrops norvegicus) caught in the Porcupine Spanish Groundfish Survey (SP-PORC-Q3) in 2021. Biomass, abundance, distribution and length frequency were analysed. The biomass of these two fishes decreased compared to the previous year. Signs of recruits were found for both species, especially for M. aeglefinus. In addition, the incidental species Pleuronectes platessa and Solea solea were not found in 2021 and Pollachius pollachius has never been caught in the time series. The crustacean N. norvergicus has increased slightly in this last survey and has done so for all the groups of sizes, thought more markedly in those larger than 21 mm. However, the mean individual weight was slightly lower than in previous years

  1Working Document to be presented to the Working Group for the Celtic Seas Ecoregion  ICES WGCSE, 4th - 13th May 2022, Ghent, Belgium  Results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius) and Norway lobster (Nephrops norvegicus) from the 2021 Porcupine Bank Survey (NE Atlantic)  O. Fernández-Zapico1, M. Blanco1, S. Ruiz-Pico1, F. Velasco1 & F. Baldó2    Instituto Español de Oceanografía (IEO-CSIC)  (1) (2)   Centro Oceanográfico de Santander Centro Oceanográfico de Cádiz   Promontorio San Martín s/n Muelle de Levante s/n (Puerto Pesquero)  39004 Santander, Spain 11006 Cádiz, Spain      Abstract This working document presents the results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius) and Norway lobster (Nephrops norvegicus) caught in the Porcupine Spanish Groundfish Survey (SP-PORC-Q3) in 2021. Biomass, abundance, distribution and length frequency were analysed. The biomass of these two fishes decreased compared to the previous year. Signs of recruits were found for both species, especially for M. aeglefinus. In addition, the incidental species Pleuronectes platessa and Solea solea were not found in 2021 and Pollachius pollachius has never been caught in the time series. The crustacean N. norvergicus has increased slightly in this last survey and has done so for all the groups of sizes, thought more markedly in those larger than 21 mm. However, the mean individual weight was slightly lower than in previous years.     Introduction The Spanish Bottom Trawl Survey on the Porcupine Bank (ICES Divisions 7c and 7k) has been carried out annually in the third-quarter (September) since 2001 to study the distribution, relative abundance and biological parameters of commercial fish in the area (ICES, 2017).  The aim of this working document is to update the results (biomass and abundance indices, length frequency and geographic distributions) of the species Melanogrammus aeglefinus (haddock), Merlangius merlangius (whiting) and Nephrops norvegicus (Norway lobster) on the Porcupine bottom trawl surveys after the results presented previously (Ruiz-Pico et al 2018, 2019, 2020; Fernández-Zapico et al. 2021).  Material and methods The Spanish Ground Fish Survey on the Porcupine Bank (SP-PORC-Q3) has been carried out annually since 2001 on board the R/V “Vizconde de Eza”, a stern trawler of 53 m and 1800 Kw. The area covered extends from longitude 12° W to 15° W and from latitude 51° N to 54° N, following the standard methodology for the IBTS North Eastern Atlantic surveys (ICES, 2017). The   2sampling design was random stratified to the area (Velasco and Serrano, 2003) with two geographical sectors (Northern and Southern) and three depth strata (<300 m, 300-450 m and 450-800 m) (Figure 1). Hauls allocation is proportional to the strata area following a buffered random sampling procedure (as proposed by Kingsley et al., 2004) to avoid the selection of adjacent 5×5 nm rectangles. More details on the survey design and methodology are presented in ICES (2017).  The tow duration is 20 min since 2016, but the results were extrapolated to 30 min of trawling time to keep up the time series.   Results and discussion Despite the problems created by the pandemic, Porcupine Groundfish Survey was carried out without major problems. In 2021, 80 valid standard hauls and 14 additional hauls were carried out. Among the additional hauls, five of them have been carried out into the standard stratification, to improve coverage in the gaps left by random sampling and nine of them, between 994 and 1484 m, to explore the continuity of the fish community in Porcupine Seabight (Figure 1).    The total stratified catch per haul decreased significantly in 2021 compared to the previous year (Figure 2). Fish represented 96% of the total catch and the species analyzed in this report represented only a small percentage of the total fish catch: haddock (0.26%) and whiting (0.02%). However, Norway lobster represented 7.7% of the total crustacean catch.  In 2021, the biomass of these two fishes decreased compared to the previous year, slightly for M. aeglefinus, and remaining quite low values in the time series, but strongly for M. merlangius, returning to medium values in the time series, after the peak of the previous year. Signs of recruits were found for both species, especially for M. aeglefinus.  The biomass and abundance of the crustacean N. norvergicus has increased slightly in this last survey and it did for all the groups of sizes, thought more markedly in those larger than 21 mm. However, the mean individual weight was slightly lower than in previous years. Melanogrammus aeglefinus (haddock) In 2021 this species decreased slightly in terms of biomass and increased marginally in terms of abundance, but remained among the low values of the time series after the peak in 2013 (Figure 3). M. aeglefinus was distributed on the Irish shelf, as usual, with some spots of biomass found to the south and west of the bank (Figure 4). After low recruitments in last three surveys, abundance of small specimens (≤ 20 cm) have increased in 2021, showing values similar to 2016 and 2017 (Figure 5, Figure 6 and Figure 7).  Merlangius merlangius (whiting) Biomass and abundance of M. merlangius have fallen, dividing by three the value of the previous year, after the strong rise in 2020 (Figure 8). All the specimens were found in three hauls around 200 m depth, in the Irish shelf (Figure 9). They ranged from 13 to 41 cm, but the most abundant sizes were around 33 cm (Figure 10).   Nephrops norvegicus (Norway lobster) The downward trend in biomass and abundance of this species from the peak of 2018 was broken in this last survey, increasing slightly compared to the previous year (Figure 11).   3The muddy slope of the Porcupine Seabight is where both adults and recruits of N. norvegicus dwell. Nephrops remained concentrated in and around the closed area. In 2021, 8 positive catches, representing 52% of the total biomass, were found in the closed area and 15 out and around the area, representing 44%. Only 5% of the biomass was found in 14 hauls in the rest of the study area (Figure 12 and Figure 13). In 2021 an increase in specimens of all sizes can be observed, especially those of the 21-26 mm range, and also those larger than 26mm (Figure 14). However, the mean individual weight was slightly lower than in the two previous years (around 26g) (Figure 15). Recruits were concentrated mainly in the northern part of the closed area, as usual, although relatively large biomass points can be seen in the central area in this last survey (Figure 16). The length distribution (Figure 17) showed a predominance of adults around 30 mm in this last survey, similarly to the previous three years. Acknowledgements		We would like to thank the R/V Vizconde de Eza crew and the IEO scientific team that made the Porcupine Spanish Groundfish Survey possible. They are included in the ERDEM5 project, which has been co-funded by the EU through the European Maritime and Fisheries Fund (EMFF) within the National Program of collection, management and use of data in the fisheries sector and support for scientific advice regarding the Common Fisheries Policy.  References  Fernández-Zapico, O., Ruiz-Pico, S., Blanco, M., Velasco, F., Baldó, F. 2021. Results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius) and Norway lobster (Nephrops norvegicus) from the Porcupine Bank Survey (NE Atlantic). Working Document presented to ICES WGCSE, 5-14 May, 2021. Remote. 14 pp.  ICES, 2017. Manual of the IBTS North Eastern Atlantic Surveys. Series of ICES Survey Protocols SISP 15. 92 pp. http://doi.org/10.17895/ices.pub.35  Kingsley, M.C.S.; Kanneworff, P. and Carlsson, D.M., 2004. Buffered random sampling: a sequential inhibited spatial point process applied to sampling in a trawl survey for northern shrimp Pandalus borealis in West Greenland waters. ICES Journal of Marine Science, 61: 12-24.  Ruiz-Pico, S., Fernández-Zapico, O., Blanco, M., Velasco, F., Baldó, F. 2020. Results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius) and Norway lobster (Nephrops norvegicus) from the Porcupine Bank Survey (NE Atlantic). Working Document presented to ICES WGCSE 2020. 17 pp.  Ruiz-Pico, S., Blanco, M., Fernández-Zapico, O., Velasco, F., Baldó, F. 2019. Results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius) and Norway lobster (Nephrops norvegicus) from the Porcupine Bank Survey (NE Atlantic). Working Document presented to ICES WGCSE 2019. 16 pp.  Ruiz-Pico, S., Blanco, M., Fernández-Zapico, O., Velasco, F., Baldó, F. 2018. Results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius), cod (Gadus morhua) and Norway lobster (Nephrops norvegicus) from the Porcupine Bank Survey (NE Atlantic). Working Document presented to ICES WGCSE 2018. 19 pp.  Velasco, F. and Serrano, A., 2003. Distribution patterns of bottom trawl faunal assemblages in Porcupine Bank: implications for Porcupine surveys stratification design. WD presented to the ICES IBTSWG, Lorient, France 25-28 March 2003. 19 pp.    4Velasco, F.; Baldó, F. & González Herraiz, I. 2018. Reporto n Nephrops results from Porcupine Bank 2018 bottom Trawl Survey. WD presented to the ICES ADGNEPH, ICES HQ, Copenhagen, Oct. 2018. 5 pp.    5Figures Galw ayIRELANDSector 1: E, F & GSector 2: F & G15º 14º 13º 12º 11º 10º 9º51º52º53º54º15º 14º 13º 12º 11º 10º 9º51º52º53º54º15W 14W 13W 12W 11W15W 14W 13W 12W 11W51N52N53N54N51N52N53N54NValid towsExtra tows Figure 1. Left: Stratification design used in Porcupine surveys from 2003, previous data were re-stratified. Depth strata are: E) shallower than 300 m, F) 301 – 450 m and G) 451 – 800 m. Grey area in the middle of Porcupine bank corresponds to a large non-trawlable area not considered for area measurements and stratification. Right: hauls performed in 2021    Yearkghaul105001000150020012002200320042005200620072008200920102011201220132014201520162017201820192020202110 %90 %Total catch Figure 2. Evolution of the total catch in Porcupine surveys (2001-2021)   6Yearkghaul1Biomass05101520012002200320042005200620072008200920102011201220132014201520162017201820192020202110 %90 %YearIndhaul1Number02040608020012002200320042005200620072008200920102011201220132014201520162017201820192020202110 %90 % Figure 3. Evolution of Melanogrammus aeglefinus biomass and abundance indices in Porcupine surveys (2001-2021). Boxes mark parametric standard error of the stratified abundance index. Lines mark bootstrap confidence intervals (α = 0.80, bootstrap iterations = 1000) 51525354200 kg2012200 kg2013200 kg2014200 kg2015200 kg20165152535415 14 13 12 11200 kg201715 14 13 12 11200 kg201815 14 13 12 11200 kg201915 14 13 12 11200 kg202015 14 13 12 11200 kg2021 Figure 4. Geographic distribution of Melanogrammus aeglefinus catches (kg×30 min haul-1) in Porcupine surveys (2012-2021)   7 Length (cm)Indhaul10.51.01.520120.51.01.520130.51.01.520140.51.01.520150.51.01.520160.51.01.520170.51.01.520180.51.01.520190.51.01.520200.51.01.55 10 15 20 25 30 35 40 45 50 55 60 65 70 75 802021 Figure 5. Mean stratified length distributions of Melanogrammus aeglefinus in Porcupine surveys (2012-2021)    8200120022003200420052006200720082009201020112012201320142015201620172018201920202021Indhaul105101520253035Melanogrammus aeglefinus  20 cm Figure 6. Mean stratified abundance of Melanogrammus aeglefinus recruits (≤ 20 cm) in Porcupine surveys (2001-2021)     5152535415 14 13 12 1140 kg200215 14 13 12 1140 kg200715 14 13 12 1140 kg201615 14 13 12 1140 kg201715 14 13 12 1140 kg201915 14 13 12 1140 kg2021 Figure 7. Geographic distribution of Melanogrammus aeglefinus recruits (≤ 20 cm) in Porcupine surveys   9Yearkghaul1Biomass0.00.20.40.60.81.01.220012002200320042005200620072008200920102011201220132014201520162017201820192020202110 %90 %YearIndhaul1Number0123420012002200320042005200620072008200920102011201220132014201520162017201820192020202110 %90 % Figure 8. Evolution of Merlangius merlangus biomass and abundance indices in Porcupine surveys (2001-2021). Boxes mark parametric standard error of the stratified abundance index. Lines mark bootstrap confidence intervals (α = 0.80, bootstrap iterations = 1000)  5152535440 kg201240 kg201340 kg201440 kg201540 kg20165152535415 14 13 12 1140 kg201715 14 13 12 1140 kg201815 14 13 12 1140 kg201915 14 13 12 1140 kg202015 14 13 12 1140 kg2021 Figure 9. Geographic distribution of Merlangius merlangus catches (kg×30 min haul-1) in Porcupine surveys (2012-2021)   10Length (cm)Indhaul10.050.150.2520120.050.150.2520130.050.150.2520140.050.150.2520150.050.150.2520160.050.150.2520170.050.150.2520180.050.150.2520190.050.150.2520200.050.150.255 10 15 20 25 30 35 40 45 50 55 602021 Figure 10. Mean stratified length distribution of Merlangius merlangus in Porcupine surveys (2012-2021)   11Yearkghaul1Biomass0123420012002200320042005200620072008200920102011201220132014201520162017201820192020202110 %90 %YearIndhaul1Number05010015020012002200320042005200620072008200920102011201220132014201520162017201820192020202110 %90 % Figure 11. Evolution of Nephrops norvegicus biomass and abundance indices in Porcupine surveys (2001-2021). Boxes mark parametric standard error of the stratified abundance index. Lines mark bootstrap confidence intervals (α = 0.80, bootstrap iterations = 1000)  5152535440 kg201240 kg201340 kg201440 kg201540 kg20165152535415 14 13 12 1140 kg201715 14 13 12 1140 kg201815 14 13 12 1140 kg201915 14 13 12 1140 kg202015 14 13 12 1140 kg2021 Figure 12. Geographic distribution of Nephrops norvegicus catches (kg×30 min haul-1) in Porcupine surveys (2011-2021)   12 15W 14W 13W 12W 11W15W 14W 13W 12W 11W51N52N53N54N51N52N53N54NNephrops norvegicusa)Weight in kgsx5 10 20Outside Inside02468101214Nephrops catchesb) Figure 13. a) Nephrops norvegicus catches in Porcupine survey 2021 showing hauls performed inside and outside the area closed to trawl (red line). b) boxplot showing the differences in catches inside an outside the closed area (only hauls with Nephrops catches are considered)    200120022003200420052006200720082009201020112012201320142015201620172018201920202021Indhaul10.00.51.01.52.0Small NephropsSurvey< 21 mma)200120022003200420052006200720082009201020112012201320142015201620172018201920202021Indhaul1051015Juvenile NephropsSurvey21-26 mmb)200120022003200420052006200720082009201020112012201320142015201620172018201920202021Indhaul1020406080100Adult Nephrops>26 mmSurveyc)Figure 14. Abundance of small Nephrops (<21 mm), juveniles between 21-26 mm and adults (>26 mm) in Porcupine survey 2001-2021   13  Years(g)2001 2004 2007 2010 2013 2016 2019020406080 Figure 15. Mean individual weight in Porcupine survey 2001-2021    5152535440 ind.201240 ind.201340 ind.201440 ind.201540 ind.20165152535415 14 13 12 1140 ind.201715 14 13 12 1140 ind.201815 14 13 12 1140 ind.201915 14 13 12 1140 ind.202015 14 13 12 1140 ind.2021 Figure 16. Geographic distribution of Nephrops norvegicus recruits (< 21 mm) in Porcupine surveys (2012-2021)     14 Length (mm)Indhaul124620142462015246201624620172462018246201924620202465 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 902021Male Female UndetLength ()density0.000.020.040.060.0820140.000.020.040.060.0820150.000.020.040.060.0820160.000.020.040.060.0820170.000.020.040.060.0820180.000.020.040.060.0820190.000.020.040.060.0820200.000.020.040.060.0810 20 30 40 50 60 70 80 902021 Figure 17. Mean stratified length distributions and length density plots of Nephrops norvegicus in Porcupine surveys (2014-2021)      

  1 Working Document to be presented to the Working Group for the Celtic Seas Ecoregion  ICES WGCSE, 6-15 May, 2020. Remote  Results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius) and Norway lobster (Nephrops norvegicus) from the Porcupine Bank Survey (NE Atlantic)  S. Ruiz-Pico1, M. Blanco1, O. Fernández-Zapico1, F. Velasco1 & F. Baldó2    Instituto Español de Oceanografía  (1) (2)   Centro Oceanográfico de Santander Centro Oceanográfico de Cádiz   Promontorio San Martín s/n Muelle de Levante s/n (Puerto Pesquero)  39004 Santander, Spain 11006 Cádiz, Spain      Abstract This working document presents the results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius) and Norway lobster (Nephrops norvegicus) caught in the Porcupine Spanish Groundfish Survey (SP-PORC-Q3) in 2019. Biomass, abundance, distribution and length frequency were analysed. These fish species remained low in the study area. In addition, the incidental species Pleuronectes platessa and Solea solea were not found in 2019 and Pollachius pollachius has never been caught in the time series. The crustacean N. norvergicus decreased this last survey after the peak of the previous year.       Introduction The Spanish bottom trawl survey on the Porcupine Bank (ICES Divisions 7c and 7k) has been carried out annually on the third-quarter (September) since 2001 to study the distribution, relative abundance and biological parameters of commercial fish in the area (ICES, 2017).  The aim of this working document is to update the results (biomass and abundance indices, length frequency and geographic distributions) of the species Melanogrammus aeglefinus (haddock), Merlangius merlangius (whiting) and Nephrops norvegicus (Norway lobster) on the Porcupine bottom trawl surveys after the results presented previously (Ruiz-Pico et al 2018; Ruiz-Pico et al 2019).  Material and methods The Spanish Ground Fish Survey on the Porcupine bank (SP-PORC-Q3) has been carried out annually since 2001 on board the R/V “Vizconde de Eza”, a stern trawler of 53 m and 1800 Kw. The area covered extends from longitude 12° W to 15° W and from latitude 51° N to 54° N, following the standard methodology for the IBTS North Eastern Atlantic surveys (ICES, 2017). The sampling design was random stratified to the area (Velasco and Serrano, 2003) with two geographical sectors (Northern and Southern) and three depth strata (>300 m, 300-450 m and 450-  2 800 m) (Figure 1). Hauls allocation is proportional to the strata area following a buffered random sampling procedure (as proposed by Kingsley et al., 2004) to avoid the selection of adjacent 5×5 nm rectangles. More details on the survey design and methodology are presented in ICES (2017).  The reduction in the tow duration (20 instead of 30 minutes) has been applied since 2016 to reduce the catches. The biomass indices of the entire time series are not affected by this reduction as the samples are still representative. The results are extrapolated to 30 minutes of trawling time to maintain the consistency of the time series.   Results and discussion The poor weather conditions posed problems during fishing operations and forced the vessel to shelter at Galway harbour several days. At the end, in 2019, 79 standard valid hauls were carried out but no additional hauls could be done (Figure 1), when usually 5-8 additional hauls are performed each survey. Besides the southeastern area of the strata 1E and the southern slope of sector 2F (Figure 1) were scarcely covered in comparison to other years.    Total stratified catch per haul increased slightly in 2019 (Figure 2). The species analyzed in this report represented only a small percentage of the total fish catch: haddock (0.3%) and whiting (0.01%). However, Norway lobster represented 13% of the total crustacean catch.  In 2019, the biomass and abundance of these two fishes remained quite low. No signs of M. merlangius recruits were found, whereas a slight increase was shown in M. aeglefinus. In addition, the abundance of specimens around 30 cm of both species also increased slightly. The biomass and abundance of the crustacean N. norvergicus decreased in this last survey. Large abundance of adults (> 26 mm), but few juveniles (21-26 mm) and fewer recruits (< 21 mm) were found as in the previous three years. Melanogrammus aeglefinus (haddock) In the last four years, the biomass and abundance of M. aeglefinus remained among the lower values of the time series after the peak in 2013. In 2019, the values were quite similar to the previous year (Figure 3).  M. aeglefinus was distributed on the Irish shelf, as usual, and a few spots of biomass were found in the south and in the west of the bank (Figure 4). After the high recruitments in 2016 and 2017, small specimens (< 20 cm) remained being scarce in the study area, although slightly higher than the previous year (Figure 5, Figure 6 and Figure 7). Most specimens ranged from 24 cm to 48 cm, but a few larger specimens (52 to 79 cm) were also found. Merlangius merlangius (whiting) Biomass and abundance of M. merlangius have been low in the time series. However, the values of the last two surveys were higher than the two previous years (Figure 8) and the rise was more marked in abundance due to the increase of specimens around 30 cm. In 2019, biomass and abundance remained quite similar to the previous year. A total of 22 specimens were found in three shallow hauls in the north of the Irish shelf, as usual (Figure 9). They ranged from 26 to 44 cm, but the most abundant sizes were around 29 cm (Figure 10).       3 Nephrops norvegicus (Norway lobster) Biomass and abundance of N. norvegicus decreased in 2019 after the highest peak of the time series in 2018 (Figure 11). The muddy slope of the Porcupine Seabight is where both adults and recruits of N. norvegicus dwell. Nephrops remained concentrated in and around the closed area, specifically in 2019, 7 positive catches, representing 49% of the total biomass, were found in the closed area and14 out and around the area, representing 50%. Only 1% of the biomass was found in 21 hauls in the rest of the study area (Figure 12 and Figure 13).  Fewer specimens were found in 2019, fewer recruits (< 21 mm), juveniles (21-26 mm) and adults (> 26mm) (Figure 14). However, the mean individual weight was slightly higher than in 2018 (around 31g.), although still among the lowest values of the time series and reflecting a large abundance of adults, but fewer recruits, as in previous years (Figure 15). Recruits were concentrated mainly in the northern part of the closed area as usual (Figure 16). The length distribution (Figure 17) showed a predominance of adults around 30 mm in this last survey, similarly to the previous three years.  Acknowledgements  We would like to thank the R/V Vizconde de Eza crew and the IEO scientific team that made the Porcupine Spanish Groundfish Survey possible. They are included in the ERDEM5 project, which has been co-funded by the EU through the European Maritime and Fisheries Fund (EMFF) within the National Program of collection, management and use of data in the fisheries sector and support for scientific advice regarding the Common Fisheries Policy.  References  ICES, 2017. Manual of the IBTS North Eastern Atlantic Surveys. Series of ICES Survey Protocols SISP 15. 92 pp. http://doi.org/10.17895/ices.pub.35 Kingsley, M.C.S.; Kanneworff, P. and Carlsson, D.M., 2004. Buffered random sampling: a sequential inhibited spatial point process applied to sampling in a trawl survey for northern shrimp Pandalus borealis in West Greenland waters. ICES Journal of Marine Science, 61: 12-24. Ruiz-Pico, S., Blanco, M., Fernández-Zapico, O., Velasco, F., Baldó, F. 2019. Results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius) and Norway lobster (Nephrops norvegicus) from the Porcupine Bank Survey (NE Atlantic). Working Document presented to ICES WGCSE 2019. 16 pp. Ruiz-Pico, S., Blanco, M., Fernández-Zapico, O., Velasco, F., Baldó, F. 2018. Results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius), cod (Gadus morhua) and Norway lobster (Nephrops norvegicus) from the Porcupine Bank Survey (NE Atlantic). Working Document presented to ICES WGCSE 2018. 19 pp. Velasco, F. and Serrano, A., 2003. Distribution patterns of bottom trawl faunal assemblages in Porcupine Bank: implications for Porcupine surveys stratification design. WD presented to the ICES IBTSWG, Lorient, France 25-28 March 2003. 19 pp. Velasco, F.; Baldó, F. & González Herraiz, I. 2018. Reporto n Nephrops results from Porcupine Bank 2018 bottom Trawl Survey. WD presented to the ICES ADGNEPH, ICES HQ, Copenhagen, Oct. 2018. 5 pp.    4 Figures Galw ayIRELANDSector 1: E, F & GSector 2: F & G15º 14º 13º 12º 11º 10º 9º51º52º53º54º15º 14º 13º 12º 11º 10º 9º51º52º53º54ºGalwayIRELAND15º 14º 13º 12º 11º 10º 9º51º52º53º54º15º 14º 13º 12º 11º 10º 9º51º52º53º54ºValid towsExtra tows Figure 1. Left: Stratification design used in Porcupine surveys from 2003, previous data were re-stratified. Depth strata are: E) shallower than 300 m, F) 301 – 450 m and G) 451 – 800 m. Grey area in the middle of Porcupine bank corresponds to a large non-trawlable area not considered for area measurements and stratification. Right: hauls performed in 2019  Yearkghaul1050010001500200120022003200420052006200720082009201020112012201320142015201620172018201910 %90 % Figure 2. Evolution of the total catch in Porcupine surveys (2001-2019)   5 Yearkghaul1Biomass05101520200120022003200420052006200720082009201020112012201320142015201620172018201910 %90 %YearIndhaul1Number020406080200120022003200420052006200720082009201020112012201320142015201620172018201910 % Figure 3. Evolution of Melanogrammus aeglefinus biomass and abundance indices in Porcupine surveys (2001-2019). Boxes mark parametric standard error of the stratified abundance index. Lines mark bootstrap confidence intervals (α = 0.80, bootstrap iterations = 1000)   6 51525354200 kg2010200 kg2011200 kg2012200 kg2013200 kg20145152535415 14 13 12 11200 kg201515 14 13 12 11200 kg201615 14 13 12 11200 kg201715 14 13 12 11200 kg201815 14 13 12 11200 kg2019 Figure 4. Geographic distribution of Melanogrammus aeglefinus catches (kg×30 min haul-1) in Porcupine surveys (2010-2019)     7 Length (cm)Indhaul10.51.01.520100.51.01.520110.51.01.520120.51.01.520130.51.01.520140.51.01.520150.51.01.520160.51.01.520170.51.01.520180.51.01.55 10 15 20 25 30 35 40 45 50 55 60 65 70 75 802019 Figure 5. Mean stratified length distributions of Melanogrammus aeglefinus in Porcupine surveys (2010-2019)    8 2001200220032004200520062007200820092010201120122013201420152016201720182019Indhaul105101520253035Melanogrammus aeglefinus1 - 20 cm Figure 6. Mean stratified abundance of Melanogrammus aeglefinus recruits (< 20 cm) in Porcupine surveys (2001-2019)     Melanogrammus aeglefinus <20 cm5152535415 14 13 12 1140 kg200215 14 13 12 1140 kg200715 14 13 12 1140 kg201615 14 13 12 1140 kg201715 14 13 12 1140 kg2019 Figure 7. Geographic distribution of Melanogrammus aeglefinus recruits (< 20 cm) in Porcupine surveys   9 Yearkghaul1Biomass0.00.20.40.60.81.01.2200120022003200420052006200720082009201020112012201320142015201620172018201910 %90 %YearIndhaul1Number0.00.51.01.52.02.5200120022003200420052006200720082009201020112012201320142015201620172018201910 %90 % Figure 8. Evolution of Merlangius merlangus biomass and abundance indices in Porcupine surveys (2001-2019). Boxes mark parametric standard error of the stratified abundance index. Lines mark bootstrap confidence intervals (α = 0.80, bootstrap iterations = 1000)    10 5152535430 kg201030 kg201130 kg201230 kg201330 kg20145152535415 14 13 12 1130 kg201515 14 13 12 1130 kg201615 14 13 12 1130 kg201715 14 13 12 1130 kg201815 14 13 12 1130 kg2019 Figure 9. Geographic distribution of Merlangius merlangus catches (kg×30 min haul-1) in Porcupine surveys (2010-2019)   11 Length (cm)Indhaul10.020.040.060.080.100.1220100.020.040.060.080.100.1220110.020.040.060.080.100.1220120.020.040.060.080.100.1220130.020.040.060.080.100.1220140.020.040.060.080.100.1220150.020.040.060.080.100.1220160.020.040.060.080.100.1220170.020.040.060.080.100.1220180.020.040.060.080.100.125 10 15 20 25 30 35 40 45 50 55 602019 Figure 10. Mean stratified length distribution of Merlangius merlangus in Porcupine surveys (2010-2019)   12 Yearkghaul1Biomass01234200120022003200420052006200720082009201020112012201320142015201620172018201910 %90 %YearIndhaul1Number050100150200120022003200420052006200720082009201020112012201320142015201620172018201910 %90 % Figure 11. Evolution of Nephrops norvegicus biomass and abundance indices in Porcupine surveys (2001-2019). Boxes mark parametric standard error of the stratified abundance index. Lines mark bootstrap confidence intervals (α = 0.80, bootstrap iterations = 1000)     13 5152535440 kg201040 kg201140 kg201240 kg201340 kg20145152535415 14 13 12 1140 kg201515 14 13 12 1140 kg201615 14 13 12 1140 kg201715 14 13 12 1140 kg201815 14 13 12 1140 kg2019 Figure 12. Geographic distribution of Nephrops norvegicus catches (kg×30 min haul-1) in Porcupine surveys (2010-2019)  15W 14W 13W 12W 11W15W 14W 13W 12W 11W51N52N53N54N51N52N53N54NNephrops norvegicusa)Weight in kgsx5 10 20Outside Inside051015Nephrops catchesb)  Figure 13. a) Nephrops norvegicus catches in Porcupine survey 2019 showing hauls performed inside and outside the area closed to trawl (red line). b) boxplot showing the differences in catches inside an outside the closed area (only hauls with Nephrops catches are considered)   14 2001200220032004200520062007200820092010201120122013201420152016201720182019Indhaul10.00.51.01.52.0Small NephropsSurvey< 21 mma)2001200220032004200520062007200820092010201120122013201420152016201720182019Indhaul1051015Juvenile NephropsSurvey21-26 mmb)2001200220032004200520062007200820092010201120122013201420152016201720182019Indhaul1020406080100Adult Nephrops>26 mmSurveyc) Figure 14. Abundance of small Nephrops (<21 mm), juveniles between 21-26 mm and adults (>26 mm) in Porcupine survey 2001-2019   Years(g)2001 2004 2007 2010 2013 20160204060802019 Figure 15. Mean individual weight in Porcupine survey 2001-2019    15 N. norvegicus <21 mm5152535440 ind.201040 ind.201140 ind.201240 ind.201340 ind.20145152535415 14 13 12 1140 ind.201515 14 13 12 1140 ind.201615 14 13 12 1140 ind.201715 14 13 12 1140 ind.201815 14 13 12 1140 ind.2019 Figure 16. Geographic distribution of Nephrops norvegicus recruits (< 21 mm) in Porcupine surveys (2010-2019)      16 Length (mm)Indhaul124620122462013246201424620152462016246201724620182465 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 902019Male Female UndetLength ()density0.000.020.040.060.0820120.000.020.040.060.0820130.000.020.040.060.0820140.000.020.040.060.0820150.000.020.040.060.0820160.000.020.040.060.0820170.000.020.040.060.0820180.000.020.040.060.0810 20 30 40 50 60 70 80 902019 Figure 17. Mean stratified length distributions and length density plots of Nephrops norvegicus in Porcupine surveys (2012-2019)      

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Results on haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangius) and Norway lobster (Nephrops norvegicus) from the Porcupine Bank Survey (NE Atlantic)

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