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Report of the NAFO/ICES Pandalus Assessment Group Meeting held by WebEx from 1 to 4 November 2021

Small pelagic fish (SPF) species such as European sardine Sardina pilchardus, European anchovy Engraulis encrasicolus, round sardinella Sardinella aurita and European sprat Sprattus sprattus play important ecological roles in the Mediterranean Sea marine ecosystem. However, changes in SPF abundance and biomass have recently been observed in the basin. Therefore, uncovering the trophic importance of SPF to their predators is key to unravelling potential ecological causes and consequences of SPF population changes related to predator dynamics. Here, we reviewed 101 published studies reporting the presence of the SPF species named above in the diet of marine predators inhabiting the Mediterranean Sea. We found that the number of species preying on SPF was highest for teleost fish species, followed by elasmobranchs, seabirds, marine mammals, cephalopods and sea turtles. These predators were both commercial and non-commercial taxa, and vulnerability ranged from medium to very high. From a conservation point of view, most predator species were considered Least Concern by the IUCN, with few exceptions such as the Balearic shearwater Puffinus mauretanicus, a Critically Endangered species. Geographic information showed that the European sardine was more important in the diet of predators from the western Mediterranean basin, while European anchovy consumption was higher on the eastern side. Round sardinella was consumed in high amounts in the Tyrrhenian Sea, and European sprat was anecdotally consumed. The importance of SPF in the diet of Mediterranean predators may indicate bottom-up control of the marine ecosystem; however, limited temporal information precluded the evaluation of temporal changes, highlighting the need to develop new studies in this area.

The selective retention of fish is a consequence of size and species-dependent fish behaviour during the trawling process. The observation of fish reactions to trawl gear is critical to understanding the behavioural mechanisms responsible for trawl selectivity and to develop future trawl gear for research. In demersal trawling, there is a need to develop more species-selective trawls to minimize discarding and bycatch in multispecies fisheries. This requires observational tools that can operate at depths and light levels encountered by the commercial fleets and with the ability to quantify the herding and capture efficiency by species and age groups of such gears. A range of optical and acoustic observation techniques has been developed over the past few decades to assist in these goals. Work with underwater cameras in fishing gear varies from the simple observation of the presence of certain species during capture to the study of the complex interactions of fishing gear and species during the trawling process. Previous work seems to show that there are different response patterns in the general behaviour of some fish species when entering a trawl. One of these behaviours is that the vertical preference in the trawl cavity differs between species. Several authors have complemented behavioural studies carried out at sea with experimental studies to further explore the interaction between fish and fishing gear. Some authors indicate that the vertical preferences of some fish species change as they move through the net towards the codend. This implies that behavioural selection can potentially change along the horizontal axis of the fishing net. A description of the bycatch (cetaceans, sharks, and skates) and fish behaviour within bottom trawling gear was given through the use of underwater cameras. The objective was to determine the most suitable fishing gear configurations to prevent the escape of the fishing catch during fishing trials carried out to test the operat

Small pelagic fish (SPF) are key organisms for the functioning of pelagic marine ecosystems. In recent decades, these species have undergone significant changes in biomass, growth and body condition in the Mediterranean Sea. Seasonal and spatial information about changes in biological and ecological traits of SPF and their relationship with environmental variables is still missing. Here, we have investigated along a latitudinal gradient in the Northwestern Mediterranean Sea the seasonal patterns of fish fitness (in terms of body condition, fat content and reproduction activity) of two important Mediterranean SPF, European anchovy (Engraulis encrasicolus) and European sardine (Sardina pilchardus). We used non-parametric multivariate analyses and Generalized Additive Models (GAMs) to investigate which environmental and trophic variables could explain observed variations during 2018–2019. Mean fat content values, relative condition index (Kn) and gonadosomatic index (GSI) were calculated monthly. We also measured individual’s stable isotope composition in muscle. Chlorophyll-a, sea surface temperature and salinity were used as environmental descriptors. The results revealed spatial and temporal variations for both species in terms of body condition, fat content and reproduction indices, as well as of stable isotopic values. GAMs showed that the variability in fitness for both species was mostly explained by environmental variables, in addition to the spatial and seasonal factors. Trophic variables contributed to explain the variability of the indices, mostly in the case of anchovy. This study provides insights into the spatial and seasonal interplay of the fitness of two important commercial species along a latitudinal gradient, and contributes to understand the fluctuations of SPF population and recent declining trends to inform proactive fisheries management at local and regional scale.

The Workshop on Mackerel, Horse Mackerel and Hake Egg Identification and Staging (WKMACHIS) is part of a series of workshops (WKMHMES, WKFATHOM) that aim to stand- ardise the process of fish egg identification and staging. Since 2000, this workshop is held in autumn of each year prior to the triennial mackerel and horse mackerel egg survey. In 2021, however, the workshop had to be held online for the first time due to the continuing SARS-CoV2 pandemic. All egg identification and staging during the workshop were undertaken using im- ages on the SmartDots WebApp, as opposed to real samples under microscopes. In advance of the workshop eggs were, however, sent to participants to be identified and staged under the microscope. The majority of the time at the workshop was spent completing 2 rounds of identifying and staging mackerel, horse mackerel, hake and similar looking eggs. The results promoted discus- sion and highlighted specific problem areas. These discussions enabled further development of standard protocols, and enhancements to the species and stage descriptions. The results were reassuring and improved from the first to the second round of the exercises. However, and par- ticularly in horse mackerel, bias in correctly identifying stage 1 eggs was higher than in previous workshops for both, experts and non-experts. These results can almost exclusively be explained by the change in workshop methodology that saw a move from a live view of the fish eggs to images. As the mackerel and horse mackerel egg surveys are carried out once every three years, the workshop functions as a refresher for expert survey participants and as an introduction for new participants in egg analyses. It should however be realised that one week of workshop for egg identification and staging, particularly if carried out online and based on images, is not sufficient to train new participants. Institutes should ensure newcomers receive a thorough training whilst also allowing more experienc

The meeting was opened by the co-Chairs Fernando González-Costas (European Union) and Ray Walsh (Canada) at 09:30 hours (UTC/GMT -3 hours in Halifax, Nova Scotia) on Wednesday, 17 August 2022.

Understanding the key factors influencing population dynamics of fish stocks requires knowledge of their spatial distribution and seasonal habitat selection, but these spatio-temporal dynamics are often not explicitly included in ecological studies and stock assessment models. This study standardized the data of sardine fishery-dependent catch-per- unit- effort (CPUE) from the west coast of Portugal using Bayesian hierarchical spatio-temporal models (BHSTM) with the integrated nested Laplace approximation (INLA). Sardine CPUE was best explained by length of the vessel, vessel ID, month, year, and location (latitude, longitude). In terms of spatio-temporal distribution, sardine biomass prediction maps showed a constant pattern that changed every quarter of the year. In addition, sardine CPUE index showed a cyclical trend along the year with minimum values in July and maximum peak in November. This approach provided insights on variables and corresponding modelling effects that may be relevant in spatio-temporal fishery-dependent data standardization, and that could be applied to other fish species and areas.

Ecosystem models, such as Ecopath with Ecosim (EwE), are useful tools for developing ecosystem-based management strategies. Model development, however, requires data for the estimation of input parameters including time series for calibration. Most small-scale fisheries lack such information, making it difficult to reliably use ecosystem models for management strategy exploration. This is the case for the Chwaka Bay fishery (Zanzibar), where an increase in dragnets has led to concerns for unsustainable development. While EwE could help to explore the impacts of gear regulations in the bay, this is hampered by the lack of time series to estimate the predator–prey interactions (vulnerabilities) in the model. Here, we explore available approaches for estimating the vulnerabilities to simulate the effects of a dragnet prohibition with and without reallocation of fishing effort. Simulations suggest that banning dragnets would be beneficial for the fishing community judged by the increase in biomass of functional groups and fishers’ profits, but not if dragnet fishers were to continue fishing in the bay by reallocating to other gears, indicated by the reduced fish biomass and fishers’ profits. The overall trend (decreasing or increasing) in the changes of functional groups, ecosystem indicators, and profits were relatively consistent across vulnerability settings, illustrating that an unfitted EwE model can be used for qualitative management strategy exploration.

The Inter-Benchmark Protocol for Iberian sardine (IBPIS) met to revise the available autumn acoustic surveys and to identify a potential recruitment index to be included in the stock assessment. The stock assessment model configuration and the short-term forecast assumptions were updated and the implications for the Precautionary Approach (PA) and Maximum Sustainable Yield (MSY) reference points and for the evaluation of the Harvest Control Rule (HCR) were investigated. The Age 0 estimates of the autumn acoustic surveys in 9aCN from 1997 onwards were considered an informative index of recruitment. The stock assessment model settings were modified for the inclusion of this recruitment index. On the one hand, the catchability of the recruitment index was modelled with a power function, and on the other hand, an extra additive SD parameter was included for all the abundance indices (Acoustic, Daily Egg Production Method and recruitment). Other settings such as the input standard deviation of log number of recruits (sigmaR) and the recruitment deviations were also fine-tuned. The short-term forecast assumptions were updated to account for the interim year recruitment newly estimated in the stock assessment. Recruitment in the interim year was changed to be the value estimated in the assessment and the recruitment in the management year was the geometric mean of the last five years (now, including the interim year estimate). With these new stock assessment and short-term forecast procedures, the prediction skill of the recruitment in the interim year and of SSB in the management year improved by 50% and 46%, respectively. Since the stock assessment results in terms of SSB, recruitment and F were very similar to those from the previous model, the group considered that such small differences would likely have a very minor impact on the reference points and on the evaluation of the HCR. The group recommends continuing monitoring potential recruitment areas other than 9aCN f

Spawning habitats of cold-water, European small pelagic fishes have shifted poleward in the last three decades coincident with gradual ocean warming. We predicted present-day, season-specific habitat suitability for spawning by European sardine Sardina pichardus in the Atlantic Ocean and Mediterranean and Black Seas, and projected climate-driven changes in suitable areas from 2050-2099 under the IPCC – RCP 8.5 scenario. Sea surface temperature and distance to the coast had the greater influences in spawning habitats, reflecting the temperature- and coastal-dependent spawning of sardines. Chlorophyll-a was the third most important explanatory variable for spawning in winter to summer. Winds were predominantly important during autumn, whilst sea surface salinity was an important driver during spring and summer. Present-day, “hotspots” for spawning were identified in regions of highly productive, salty waters, where SST was between 6 and 18°C from autumn to spring or 16 and 25°C during summer and favourable winds occurred that would retain eggs and larvae closer to the coast (< 250 km). For future scenarios, forecasts indicate that environmental optima for spawning is projected to be in regions where SST varies between 11°C and 18°C from autumn to spring; and between 18°C and 24°C during summer. However, a negative relationship between phytoplankton productivity and habitat suitability induced by warming is likely to occur in the future. Projections suggest that suitable spawning habitats in all seasons will shift to higher latitudes, with a prominent range expansion along the coast of Norway during winter and autumn (> 83%). The total spawning area, however, was projected to contract in the future during spring (-10.5%) and autumn (-4.1%) due to losses of currently suitable areas along the Atlantic African Coast and Mediterranean Sea. Such regions currently support the greatest sardine stocks but climate-driven warming and decreased plankton productivity are projected

WGHANSA 2022. (25/11/2022 - 29/11/2022. Online)

Flemish Cap cod collapsed in the early 90’s after facing multiple threats due to climate variability and anthropogenic pressures. A master 35-year cod growth chronology was reconstructed in the present study by using sclerochronology techniques. Three additional chronologies were developed to account for the age-dependent effect of maturity and fishing intensity on growth. All chronologies showed that cod growth has decreased over the years and it is currently at the minimum level in the historic of data series. Hierarchical mixed-effects models were applied to the master chronology to identify extrinsic drivers of growth. The master chronology was divided into 3 periods: Premoratorium (1988-1998), Moratorium (1999-2009), and Postmoratorium (2010-2019). Our results showed that drivers of cod growth in the Flemish Cap varied between periods (Premoratorium: bottom temperature and fishing mortality, Moratorium: cod and pandalus abundance, and Postmoratorium: cod abundance and thickness of the cold intermediate layer). Our results suggest that density-dependence processes, food availability, and global warming may be behind the lack of recovery of the Flemish Cap cod stock. The Flemish Cap cod growth chronology shows variations on growth over time and identifies its drivers, having the potential to be included in the NAFO stock assessments or to be used to set dynamic reference points that guarantees the stock sustainability. Introduction

Cetacean strandings represent unique opportunities to collect biological material from these wild animals and obtain information on their population statuses. Here, we apply biological and pathological perspectives to analyze stranded cetaceans collected along the Sardinian coast (Italy) between 2006 and 2011. We quali-quantitatively explore the primary causes of deaths, and use Bayesian Hierarchical Models (BHMs) to explore the potential effects of cetacean sex, age, body length, and month, year, and stranding location on Dicloro Difenil Tricloroetano (DDT) and Polychlorinated Biphenyl (PCB) contaminant loads. Although natural causes, such as bacterial and virus infections, were identified to be the main causes of death among the stranded cetaceans, fisheries also played an important role among the anthropogenic causes of death. The BHMs revealed that both contaminants were positively related to the length, sex and age of the cetaceans, and that higher concentrations of these contaminants were mainly found in larger and older individuals. Despite the scattered nature of these data, the present study contributes valuable insights into the major causes of death of stranded cetaceans, and adds to growing worldwide efforts to biomonitor cetaceans.

Although there is a great knowledge about individual anthropogenic threats to different fish species in the Mediterranean Sea, little is known about how these threats accumulate and interact to affect fish species richness in conjunction with environmental dynamics. This study assesses the role of these threats in the fish richness component and identifies the main areas where the interaction between fish species richness and threats is highest. Our results show that fish richness seems to be higher in saltier and colder areas where the chlorophyll-a and phosphate concentrations are lower. Among the anthropogenic threats analyzed, the costal impact and the fishing effort seems to be the more relevant ones. Overall areas with high fish richness are mainly located along the western and northern shores, with lower values in the south-eastern regions. Areas of potential high cumulative threats are widespread in both the western and eastern basins, with fewer areas located in the south-eastern region. By describing the spatial patterns of the fish richness and which drivers explain these patterns we can also identify which anthropogenic activities can be managed more effectively to maintain and restore marine fish biodiversity in the basin.

NAFO has used kernel density analyses to identify VMEs dominated by large-sized sponges, sea pens, small and large gorgonian corals, erect bryozoans, sea squirts (Boltenia ovifera), and black corals. That analysis generates polygons of significant concentrations of biomass for each VME indicator which are spread across the spatial domain of the NAFO fishing footprint. There is potential for bottom contact fishing to induce changes in both the amount and configuration of habitat (e.g., decreased polygon size, increased polygon isolation, and increased edge area) through direct and indirect impacts, and it is unknown to what degree such changes may already have taken place given the long fishing history of the area. In the Report of the 13th Meeting of the NAFO Scientific Council Working Group on Ecosystem Science and Assessment (WGE-ESA), preliminary work on assessing and monitoring habitat fragmentation was presented. Here we continue that work by recalculating the indices after removing connections that are not identified through particle tracking models. We have reanalyzed the nearest neighbour distances and PX, a proximity index, for the VME polygons noted above, and for the new closed areas that will come into effect 1 January 2022. We show that PX when applied to the new closures appears sensitive to their spatial configuration which bodes will for the ability of this index to identify habitat fragmentation in the future, brought about through fishing activities and/or natural disturbances.

Scientific Council reviewed and finalized the working paper drafted by the Precautionary Approach Working Group (PA-WG). The final draft of this working paper, which will be presented to the Precautionary Approach workshop (15-16 August 2022) and WG-RBMS (17-19 August 2022), is attached to this report as Appendix II

There are presently no existing frameworks or approaches in NAFO to assist in determining under what conditions scientific surveys employing bottom-contacting gear can be permitted in protected areas. Fisheries and Oceans Canada (DFO) has produced a Canadian National Framework to guide the evaluation of scientific surveys within protected areas inside the Canadian waters. The objective of this document is to apply to the scientific surveys that are carried out in the NRA the framework developed by the DFO for the collection of information that can help managers in the decision of whether the actual scientific surveys can sample or not in the closed areas to bottom fishing activities.

Report of the NAFO Working Group on Improving Efficiency of NAFO Working Group Process (E-WG) Meeting held by WebEx 22 February 2022

Report of the Scientific Council (in conjunction with NIPAG) Meeting held by WebEx from 1 to 4 November 2021

Length-based methods have been widely applied to estimate biological parameters and understand the dynamics of marine resource populations within data-limited stocks. However, to date few studies have tested the sensitivity of parameters in length-based methods examining stocks with different traits and fishery contexts. In the Bay of Biscay and the Iberian Coast ecoregion, SE Europe (International Council for the Exploration of the Sea - ICES, Divisions 8 and 9a), many commercial resources are considered data-limited, and either little is known about their fisheries stock statuses or gaps remain in currently available assessments. Therefore, this study focuses on two of the most used length-based methods, which ICES considers to be the most appropriate to evaluate data-limited stocks, namely length-based indicators (LBI) and the length-based spawning potential ratio (LBSPR). Both methods have been applied to assess the stock statuses of various relevant species in the study area, such as: the small-spotted catshark (Scyliorhinus canicula), European anchovy (Engraulis encrasicolus), blackspot seabream (Pagellus bogaraveo), pouting (Trisopterus luscus), pollack (Pollachius pollachius), and Norway lobster (Nephrops norvegicus). For each stock, model results were compared with available knowledge on their current status. Furthermore, this paper discusses whether unexpected results are related to violations of the main model assumptions (constant total mortality and recruitment, and logistic selectivity) or to a lack of representativeness of stock length composition. A sensitivity analysis was conducted on the two most important input parameters: L∞ (von Bertalanffy asymptotic average maximum body size) and M/k (ratio of natural mortality to von Bertalanffy growth rate). This analysis concluded that the variation/misspecification of both parameters (M/k and L∞) had a considerable impact on the results given by both methods, and that this effect is more significant in th

Greenland halibut (Reinhardtius hippoglossoides), American plaice (Hippoglossoides platessoides), Atlantic cod (Gadus morhua), yellowtail flounder (Limanda ferruginea), redfish (Sebastes spp.), witch flounder (Glyptocephalus cynoglossus), roughhead grenadier (Macrourus berglax), thorny skate (Amblyraja radiata), white hake (Urophycis tenuis), squid (Illex illecebrosus) and capelin (Mallotus villosus) indices from the bottom trawl survey that Spain carries out in Spring since 1995 in Divisions 3NO of the NAFO Regulatory Area are presented. In 2020, the survey was not carried out due to the COVID pandemic situation. The presented indices are biomass by stratum, total length distribution and a and b parameters for the length-weight relationship; age distribution is also presented for Greenland halibut, Atlantic cod and American plaice.

Spanish catch and effort information used in this Report is based on the preliminary logbook data contributed by the Spanish Administration. The logbooks information for 2021 was available haul by haul. Total effort of the Spanish fleet in 2021 was 1,170 fishing days. Table 1 presents the preliminary Spanish catches by species and Division in 2021 in NAFO Regulatory Area. These catch figures are preliminary, the final catches to carry out the NAFO assessments will be agreed by the NAFO Joint Commission-Scientific Council Catch Estimation Strategy Advisory Group (CESAG).

Data review for 3LN redfish in preparation for an updated management strategy evaluation

During the 14th NAFO Working Group on Ecosystem Science and Assessment (WGESA) virtual meeting new preliminary data on deep-water corals and sponges were presented from the 2021 EU; EU-Spain and Portugal and Canadian bottom trawl groundfish surveys. The data was made available to the NAFO WGESA to improve mapping of Vulnerable Marine Ecosystem (VME) indicator species in the NAFO Regulatory Area (Divs. 3LMNO). During the 6th meeting of the NAFO Scientific Council WGESA, new quantitative spatial analyses were applied for corals and sponges for all the available data within the NAFO Regulatory Area (NAFO, 2013). Outcomes from those analyses produced the following thresholds for VME indicator species: 75 kg per tow for sponges, 0.6 kg per tow for large gorgonians, 0.15 kg per tow for small gorgonians, and 1.4 kg per tow for sea pens. Based on these thresholds, deep-water coral and sponge catches were identified and mapped, and overlaid with the current closed areas and VME polygons. New thresholds and VME polygons were presented at the 12th WGESA meeting using additional data since 2013 (NAFO, 2020). These are: 100 kg per tow for sponges, 0.6 kg per tow for large gorgonians, 0.2 kg per tow for small gorgonians, 1.3 kg per tow for sea pens, 0.35 for Boltenia sea squirts, 0.2 for bryozoans and 0.4 for black corals. Therefore, VME polygons illustrated on the figures below are the modified ones, accepted by SC.

In the Iberian Coast region, the common sole (Solea solea) is considered a very relevant species due to its high commercial value. Despite its importance, the current status of this stock is still poorly known due to the scarcity of available data to apply formal assessment methods. In data-poor situations length-based methods have been widely applied to estimate biological parameters and to understand the dynamics of marine stocks. In this study we evaluate the status of common sole in the Iberian Coast region using the following three different length-based methods: (1) the length-based indicators, (2) the length-based spawning potential ratio and (3) the mean length-based mortality estimators. Overall, the three methods agree that this stock appears to be exploited at the maximum sustainable yield level, the immatures are well preserved whereas the proportion of large mature individuals is relatively low, although it has been increased in the last years. Assessing the status of this valuable stock through data-limited methods is the first step towards designing and implementing effective management measures.

In February 2019, seamounts of the Discovery Rise, SE Atlantic (41–45°S, 3°W - 3°E), were explored in support of the application of the Ecosystem Approach to Fisheries Management in the Southeast Atlantic Fisheries Organization (SEAFO) Convention Area. Video records of the seafloor were produced by the Video-Assisted Multisampler System (VAMS) along 15 valid transects conducted in plateau and flank areas of Shannon, Tablemount, Discovery and Heardman seamounts at depths ranging from 394 to 1839 m. Nine benthic seascapes were classified and described based on substrate hardness, texture, slope, physical and biological modifiers as observed in the video images. Predominant water masses were estimated from temperature, salinity and dissolved oxygen vertical profiles obtained by CTD casts in the vicinity of each transect. A total of 366 fishes were seen (total observation time = 25.0 h) and classified in 32 morphotypes, included in 9 orders and 12 families. Most fish morphotypes (14) were included in the Macrouridae family. Family Moridae, on the other hand, included 65.3% of all fish records (239), with two particularly abundant morphotypes: Laemonema sp. (116) and Guttigadus sp. (92). Thirteen cephalopods were observed and classified in five morphotypes; the oegopsid squid Moroteuthopsis ingens was the most abundant of them (6). Despite the taxonomic uncertainties associated with video identifications, the explored region was found to contain a mixture of tropical – subtropical and subantarctic faunas of the Atlantic. Similarities of fauna composition and non-directional beta diversity estimates revealed some degree of seamount identity, but 57.5–61.9% of morphotypes were shared among seamounts (Jaccard = 0.425, Sørensen = 0.381). Fishes and cephalopods were more frequently observed on the shallower plateau areas under the influence of warmer and more oxygenated Antarctic Intermediate Waters. Depth and related factors did not influence richness, but dissimilarities in

The common sole (Solea solea) is a species of flatfish of great commercial relevance in the northern Atlantic Iberian waters. Although many studies investigated the early life-stage of this species, little is known on the adult phases and the size structure of the population. Here we provide an analysis of the spatiotemporal distribution of adult’s common sole occurrence, conditional-to-presence biomass and median length in northern Atlantic Iberian waters using a Bayesian approach and three different spatiotemporal model structures that characterize the fundamental distributional patterns of fish as either persistent, opportunistic or progressive. Results highlight that the distribution of common sole adults in the area has been persistent over the years and that is partially affect by the bathymetry. Three main abundance hotspots were identified coinciding with spatial closure areas restricted to the fishing activity. Additionally, results show that small specimens tend to aggregate in shallower waters, while larger specimens inhabit deeper waters. Understanding the spatiotemporal distribution of the common sole population could improve our knowledge of this species and help to design more accurate biomass index that could be used to calibrate stock assessment models.

The meeting was opened by the co-Chairs Fernando González-Costas and Steven Cadrin at 09:00 hours (Atlantic Daylight Time in Halifax, Nova Scotia) on Thursday, 19 May 2022.