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An assessment of the cod stock in NAFO Division 3M is performed. A Bayesian model, as used in the last assessments, was used to perform the analysis. As there are inconsistencies with total catch of the last four years, a prior was added for 2011 and 2012 catch, the Daily Catch Report data were used in 2013 and the STATLANT21A in 2014. Results indicate a general increase in SSB since 2005, reaching a value well above Blim since 2009.

Since 2003, a stratified random spring bottom trawl survey was conducted by Spain in Division 3L of NAFO Regulatory Area (Flemish Pass). The surveys were carried out by the R/V “Vizconde de Eza” using bottom trawl net type Campelen. Entire series of mean catches, biomass and length distribution for Atlantic cod, roughhead grenadier, redfish, thorny skate and black dogfish are presented for the period 2003-2014.

Since 2003, a stratified random summer bottom trawl survey was conducted by Spain in the NAFO Regulatory Area of Division 3L (Flemish Pass). The surveys were carried out by the R/V “Vizconde de Eza” using bottom trawl net type Campelen. Entire series of mean catches, biomass and length distribution for Greenland halibut, American plaice and witch flounder are presented for the period 2003-2014. Greenland halibut biomass and abundance estimates show an increasing trend since 2011, reaching the maximum values in the series in 2008 and 2014. In last years it can be seen a presence of juveniles (around 12-15 cm). American plaice biomass and abundance estimates present an increasing trend since 2010, reaching in 2014 the highest value in the series. Regarding witch flounder, the biomass and abundance decreased in 2014, but there is no a clear trend in the whole period 2003-2014.

Compensatory responses are important because they increase spawning stock biomass (SSB) growth rates in depleted fish populations. We analyze recruits per spawner (R/SSB) and spawners per recruit (SSB/R) data from six well-studied depleted, or depleted and recovering, Northwest Atlantic groundfish stocks for evidence of compensatory responses. All stocks had periods of high R/SSB at low SSB; however, R/SSB showed considerable variability, and significant compensatory responses were only found in two stocks. For compensation in SSB/R, relationships were significant for three of the stocks. We examined the potential impact of compensation in R/SSB and SSB/R on SSB growth rate and concluded that SSB/R could have a greater potential impact on enhancing SSB growth rate in depleted stocks. Overall, cod (Gadus morhua) populations showed greater compensation than flatfish, mainly due to the lower potential in flatfish to increase SSB/R. This suggests that cod are more resilient to overfishing than are flatfish. Estimates of population growth rate at low stock size, which ignore compensation in SSB/R, will underestimate maximum SSB growth rates. Compensation in both R/SSB and SSB/R should both be considered when evaluating stock productivity, sustainable harvest levels, and biological reference points.

The 3M redfish assessment is focused on the beaked redfish, regarded as a management unit composed of two populations from two very similar species: the Flemish Cap S. mentella and S. fasciatus. The reason for this approach is the historical dominance of this group in the 3M redfish commercial catch until 2005. However a new golden redfish fishery (S. marinus) started on September 2005 on shallower depths of the Flemish Cap bank above 300m, and the Flemish Cap cod fishery reopened in 2010. These new realities implied a revision of catch estimates, in order to split recent redfish commercial catch and by-catch from the major fleets on Div. 3M into golden (S. marinus) and beaked (S. mentella and S. fasciatus) redfish catches. The Extended Survivor Analysis assessment used as tuning file the 1989-2014 EU survey abundance at age matrix included in a revised input framework. Continuing pressure over Flemish Cap redfish stocks by cod predation, at levels higher, or much higher, than the levels prior to 2006 lead to higher natural mortalities since then. Natural mortality have been tuned to survey at age data 2006 onwards by the sensitivity analysis preceding each assessment, and on 2013-2104 has a best estimate at slightly higher level from previous years. A 2015-2011 retrospective XSA was carried out, confirming that the present assessment is very much in line with their immediate predecessors. Above average year classes coupled with low fishing mortalities allowed a rapid growth of biomass and abundance since 2003, pulling the stock to a 2008-2010 high. From 2009 onwards abundance went down for causes other than fishing, being still in 2014 at a level well above the 1990’s low. Biomass and female spawning biomass (SSB) also declined but these trends were reversed by 2011-2012. Due to individual growth of survivors stock biomass has improved on recent years and is still on 2013-2014 at high levels. Recruitment at age 4 increased from 2002 till 2006 and was maintained at

Data for roughhead grenadier (Macrourus berglax), thorny skate (Amblyraja radiata) and white hake (Urophycis tenuis) from the Spanish Spring survey are presented. Abundance and biomass were estimated for roughhead grenadier and thorny skate for the period 1997-2014 and for white hake for the period 2001-2014. The length distribution is presented as numbers per haul stratified mean catches for the last five years (2010-2014). The roughhead grenadier indices showed no discernible trend until 2012, reaching a maximum in 2004 - 2006 and afterwards stabilised at levels slightly higher than in the early years. In the last two years a decline was appreciated in the indices, reaching in 2014 one of the lowest values of the entire time-series. Thorny skate indices follow a large oscillating trend, dropping in 2007 and being since then more or less stables at a low level, reaching the minimum of the series in 2014. White hake indices were highest in 2001 and then showed an overall decreasing trend until 2008 with low values. Indices increased since then until 2013 but declined again in 2014. A small recruitment event was detected in 2005 and in 2013, with individuals between 16 - 26 cm.

An ecosystem approach is widely recognized as desirable for fisheries management. A key element is the development of indicators for the assessment of ecosystem status.Weevaluated the status of two, exploited marine ecosystems, Southern Grand Banks of Newfoundland and Flemish Cap, using a multivariate analysis and a suit of ecological indicators. We used data obtained from two multispecies bottom trawl surveys performed by the Spanish Administration in the Southern Grand Banks (3NO survey) from 2002 to 2014, and the EU in the Flemish Cap (3M survey) from 1991 to 2014. We studied the dynamic of major demersal fish assemblages (38–300, 301–600, and 601–1460 m depth in 3NO; 129–250, 251–600, and 601–1460 min 3M). Temporal changes and trends in fish assemblages’ structure were tested using a non-metric multidimensional scaling and four indicators (mean trophic level, species evenness, species diversity, and species richness). This study revealed the importance of calculating indicators in each assemblage and the usefulness of indices to compare areas and periods under different fishing pressure.

The overarching aim of this year’s meeting was to know the general results of the last research survey carried out in summer 2013 and to agree on the objectives and logistical issues (scientific equipment, staff etc.) for the next research survey carried out in summer 2014.

M is one of the most influential quantities in fisheries stock assessment and in providing management advice. Cod 3M Bayesian XSA model assumes a lognormal prior over M being constant for all ages and years. Using the same data as in the 2013 assessment, four different scenarios over M were tested: the one assumed in the assessment (M constant over ages and time), one with age variable over three classes and constant for time, one with time variable over three periods and constant over ages, and one variable over three age classes and three periods of time. Although the results indicate the forth scenario as the best one, inconsistencies in them make very difficult to choose one of the scenarios based on the information available and further studies are needed. Nevertheless, it would be advisable that this uncertainty on M will be tested in the MSE process. The scenario 4 could be a good starting point to analyse the uncertainty on M in the 3M cod MSE.

Data for roughhead grenadier (Macrourus berglax), thorny skate (Amblyraja radiata) and white hake (Urophycis tenuis) from the Spanish Spring survey are presented. Abundance and biomass were estimated for roughhead grenadier and thorny skate for the period 1997-2013 and for white hake for the period 2001-2013. The length distribution is presented as numbers per haul stratified mean catches for the last five years (2009-2013). The roughhead grenadier indices show no trend during the entire period, reaching a maximum in 2004 - 2006 and afterwards stabilised at levels slightly higher than in the early years. Thorny skate indices follow a large oscillating trend, dropping in 2007 and being since then more or less stables at a low level. White hake biomass index was highest in 2001 and showed an overall decreasing trend since then to 2008, reaching almost the level of 2002 in 2013, although at very low levels compared with the 2001 one. A small recruitment event was detected in 2004 and in 2013, with individuals between 16 - 26 cm.

Since 2003, a stratified random spring bottom trawl survey was conducted by Spain in Division 3L of NAFO Regulatory Area (Flemish Pass). The surveys were carried out by the R/V “Vizconde de Eza” using bottom trawl net type Campelen. Entire series of mean catches, biomass and length distribution for Atlantic cod, roughhead grenadier, redfish, thorny skate and black dogfish are presented for the period 2003-2013.

The aim of this analysis is to describe the spatial and seasonal fleet activity and cod distribution in the Flemish Cap area in the period 2008-2013. Especial attention is paid to the relative distribution of mature and immature sub-stocks, as well as individuals bellow 41 cm size (Minimum Landing Size, MLS). The following data sources were analyzed for different periods depending on the data availability and the aim followed: Daily Catch Reports (DCR), Vessel Monitoring System (VMS), Spanish Scientific Observers, EU Flemish Cap surveys.

Since 1995, Spain carries out a spring stratified random bottom trawl survey in Div. 3NO of the NAFO Regulatory Area. Total mean catches, biomass and mean numbers for yellowtail flounder (Limanda ferruginea) are presented for the period 1995-2013, for redfish (Sebastes spp) for the period 1997-2013 and for witch flounder (Glyptocephalus cynoglossus) for the period 2002-2013. Detailed indices are presented from 2009. Yellowtail flounder does not show a clear trend since 1998; its indices are almost constant throughout this period, with a slight increase in the last five years. Redfish indices oscillate greatly over time, probably because the gear does not sample adequately aggregating pelagic species. There was a sharp increase in 2009, being more or less stable since then at a high level, comprising the 3N around the 90% of the total biomass in last years. Good year classes have not been registered recently. Witch flounder is very scarce and also lacks a clear trend in the data series, being the values always poor. Recruitment was quite good at the beginning of the series but very poor in recent years.

There are two species of redfish in Divisions 3L and 3N, the deep-sea redfish (Sebastes mentella) and the Acadian redfish (Sebastes fasciatus) that have been commercially fished and reported collectively as redfish in fishery statistics. Redfish in Div. 3LN is regarded as a management unit composed of two Grand Bank populations from those two very similar redfish species. The present ASPIC assessment is based on the logistic form of a non-equilibrium surplus production model (Schaeffer, 1954; Prager, 1994), adjusted to a standardized catch rate series (Power, 1997) and to most of the stratified-random bottom trawl surveys conducted in various years and seasons in Div. 3L and Div. 3N from 1978 onwards. Both CPUE and surveys were used with all observations of each series. This assessment is not a follow up of the previous ones (Ávila de Melo et al., 2012 and 2010). The logistic Schaefer production model (1954) incorporated in ASPIC operating model (Prager, 1994) can not cope anymore with the most recent biomass increases observed in both spring and (mainly) autumn Canadian 3LN surveys, unless it is allowed to provide unrealistic assessment results. And continuing to strip off the highs of each one of these series, in order to get a picture in line to what is the perception of the stock history from commercial and survey data trends, is no longer a valid option, as reflected on the last STACFIS research recommendation on this matter (NAFO, 2012). Being so, input has been reframed opening room to a new combination of Canadian autumn 3L and 3N surveys. The inclusion of the Spanish spring survey on Div. 3N and the removal of the historical CPUE series have also been considered. Two selected frameworks options have finally run with MSY kept constant at an initial starting guess, instead of being estimated by the model. Before entering the latest (2013) ASPIC Suite flow, the input selected from exploratory analysis was submitted to a sensitivity test in order to evaluate th

The Newfoundland Shelf supported one of the world’s greatest fisheries until the main commercial species collapsed more than two decades ago. We calculated three ecological indices for individual populations and five for community from the data obtained in the research surveys conducted by Spain in NAFO Regulatory Area Divisions 3NO between 2002 and 2013. We use data for 24 species to study the dynamics of major demersal fish assemblages (38–300, 301–600, and 601–1460 m depth) and evaluated how they have responded to different levels of exploitation. Trends and changes for individual populations (abundance and biomass, intrinsic population rate of growth, and mean length) and for all the community (ABC curves, indices of faunal diversity, proportion of non-commercial species, mean length in community and size spectra) were used to test ecological trends. Indices showed no homogeneous status and responded to different exploitation patterns, management, and environmental regimes in each assemblage. Our results show an improvement in the shallower and deeper assemblages and that fishing effort does not explain differences among each assemblage.

The present assessment evaluates the status of the 3M American plaice stock. The catch at age matrix, EU survey abundance at age and the respective mean weights were updated. The XSA and a VPA-type Bayesian model were applied to this stock, but the XSA presented unrealistic results. The surveys and models indicate that the stock suffered a continuous decline, even with catches kept at a low level since 1996. A general decrease is observed in the biomass and abundance estimated by the several surveys. The EU survey and VPA-type Bayesian model indicates only poor recruitment from 1991 to 2005 year class. SSB recorded a minimum in 2009, in recent years SSB indices increase with the income of the strong 2006 year class in the SSB but in 2013 this increase seems to halt mainly as there were fewer older fish (ages 16+). There are no changes in the perception of the stock status from last assessment (2011). This stock continues to be in a poor condition, despite the apparent improvement of the recruitment since 2006 (mainly due to the 2006 year class). Although the level of catches is low since 1996, this stock has been kept at a low level.

Data from the EU (Spain-Portugal) bottom trawl surveys in the Division 3M of the NAFO Regulatory Area (2004-2013) were analyzed to examine patterns on this zone of groundfish assemblage structure and diversity in relation to depth. 1699 hauls between 129 and 1460 m in depth were carried out. We focused on the 29 most abundant species, which made up 87.5% of the catch in terms of biomass. Assemblage structure was strongly correlated with depth. For the most part, changes in assemblages seem to be fairly continuous, although there were more abrupt changes at 600 m. Three main assemblages were identified. A shallow assemblage was found in the shelf. Assemblage I (Shallow) comprises the strata with depths lesser than 250 m and include American plaice (Hippoglossoides platessoides), witch flounder (Glyptocephalus cynoglossus) and Atlantic cod (Gadus morhua). Assemblage II (Intermediate) includes the strata with depths between 251 and 600 m and comprises Acadian redfish (Sebastes fasciatus), Arctic eelpout (Lycodes reticulates), thorny skate (Amblyraja radiata), longfin hake (Phycis chesteri), deepwater redfish (Sebastes mentella), spinytail skate (Bathyraja spinicauda) and Northern wolffish (Anarichas denticulatus). Three species are present in the two first assemblages: Atlantic wolffish (Anarichas lupus), golden redfish (Sebastes marinus) and spotted wolffish (Anarichas minor). Assemblage III (Deep) contains the depth strata greater than 601 m. Marlin-spike (Nezumia bairdii), scaly dragonfish (Stomias boa), Greenland halibut (Reinhardtius hippoglossoides), sloane’s viperfish (Chaulonius sloani), black dogfish (Centroscyllium fabricii), Snubnosed spiny eel (Notacanthus chemitzii), roughhead grenadier (Macrourus berglax), roundnose grenadier (Coryphaenoides rupestris), blue antimora (Antimora rostrata), threadfin rockling (Gaidropsarus ensis), bean’s sawtoothed eel (Serrivomer beanii), Northern cutthroat eel (Syphanobranchus kaupii), lanternfish (Lampanyctus sp), vahls’s

Since 2003, a stratified random summer bottom trawl survey was conducted by Spain in the NAFO Regulatory Area of Division 3L (Flemish Pass). The surveys were carried out by the R/V “Vizconde de Eza” using bottom trawl net type Campelen. Entire series of mean catches, biomass and length distribution for Greenland halibut, American plaice and witch flounder are presented for the period 2003-2013. Greenland halibut biomass and abundance estimates show an increasing trend along the whole period, reaching a maximum of mean catch and number in 2008. A great increase of small individuals (around 12-15 cm) can be seen in 2013. American plaice biomass and abundance estimates present an increasing trend since 2010. Regarding witch flounder, the biomass and abundance increased in 2013, but there is no a clear trend in the whole period 2003-2013.

An assessment of the cod stock in NAFO Division 3M is performed. A Bayesian model, as used in the last assessments, was used to perform the analysis. As there are inconsistencies with total catch of the last three years, a prior was added for 2011 and 2012 catch and the Daily Catch Report data were used in 2013. Results indicate a general increase in SSB since 2005, reaching a value well above Blim since 2009.

Se trata de un libro que pretende divulgar a la sociedad las principales investigaciones multidisciplinares llevadas a cabo por el Instituto Español de Oceanografía durante su primer siglo de vida, y dar a conocer la historia del organismo, de su Sede Central y de los nueve centros oceanográficos repartidos por los litorales mediterráneo y atlántico, en la península y archipiélagos.