Northwest Atlantic Fisheries Organization Research Articles

Международная организация по рыболовству в Северной Атлантике: особенности регулирования промысла в настоящее время и в ближайшей перспективе

This article describes the area where fisheries are regulated by the Northwest Atlantic Fisheries Organization (NAFO), as well as the regulatory measures for it, both currently in use and recommended for application. Possible regulatory setbacks for Russian fisheries presented by both actual and developing fishing rules are analyzed.

Trends in larval densities, spawning timing, and site quality of capelin (Mallotus villosus) across bays and habitats in Newfoundland, Canada

Abstract Capelin is a short-lived forage fish species that underwent a population collapse in 1991 on the Newfoundland and Labrador Shelf, Canada (Northwest Atlantic Fisheries Organization Divisions 2J3KL) and has not recovered. The collapsed stock is characterized by delayed spawning timing and low recruitment. As year-class strength is set early in life, long-term larval monitoring at an intertidal spawning site in Trinity Bay (TB) is used as a proxy for stock-wide recruitment. Capelin spawn at both intertidal and subtidal habitats; however, there is minimal larval information from bays with a high incidence of subtidal spawning. We aimed to (i) compare inter-annual trends in temperatures, timing of spawning, and annual larval densities between two northeastern bays [TB and Notre Dame Bay (NDB)] and (ii) compare habitat quality metrics and larval densities between subtidal and intertidal sites in NDB. The date of first spawning in TB and NDB was positively correlated, suggesting that years with delayed spawning are experienced shelf-wide. While larval density was lower in NDB compared to TB, inter-annual trends were similar. In NDB, larval densities at both intertidal and subtidal spawning habitats were similar within a year, but temperatures and the proportion of dead eggs were lower at subtidal sites. These habitat quality metrics, however, were not related to annual larval density. These findings improve our knowledge on sources of capelin productivity, including the potential importance of subtidal spawning to recruitment dynamics.

Spatiotemporal modelling of Greenland halibut maturation across the Northwest Atlantic

AbstractModelling life history trait variation at appropriate spatial and temporal scales is crucial for understanding population dynamics and developing effective fisheries management strategies. However, most efforts to model life history traits ignore spatial correlations and make a priori assumptions about the spatial structuring of populations, potentially clouding the ability to recognize true spatial structure. Here we develop spatiotemporal maturation models for Greenland halibut (Reinhardtius hippoglossoides) in the Northwest Atlantic, a species with large-scale movement patterns that can lead to uncertainty regarding effective stock boundaries. Our analysis using data from three Fisheries and Oceans Canada survey regions, Baffin Bay and Davis Strait in the eastern Canadian Arctic, Newfoundland and Labrador (NL), and the northern Gulf of St. Lawrence (GSL), is the first at such a large spatial scale. We also extend the traditional binary maturity status to a multinomial one that accounts for seasonal changes in maturation. Results show a decreasing temporal trend in size at maturity across the entire area. Spatial results regarding size at maturity provide new insight linking Greenland halibut south of Newfoundland (Northwest Atlantic Fisheries Organization Subdivision 3Ps) to the GSL stock rather than the NL stock. Results also highlight parts of the Davis Strait area, where size at maturity is smaller than in waters both north and south. Multinomial model results identify areas in GSL and Davis Strait that may be important for reproductive development in the summer and fall. Our analyses also reveal constraints on size at maturity that correspond with the well-known positive association between fish length and bottom depth. Broad-scale analyses of high resolution spatial patterns in life history traits, such as those performed here for Greenland halibut maturation, may identify recurrent patterns of association with environmental or habitat characteristics that might not otherwise be evident on a stock- or survey-specific basis.

Comparative analysis of the age estimates for greenland halibut <i>Reinhardtius hippoglossoides matsuurae</i> in the North-West Pacific based on different methodological approaches

Significant decline in abundance of greenland halibut Reinhardtius hippoglossoides matsuurae in the North-West Pacific is one of the reasons for development the methods of this species age determination using different age-recording structures. The study is based on recommendations of the Northwest Atlantic Fisheries Organization (NAFO) and International Council for the Exploration of the Sea (ICES). Underestimation of age is found for the records on scales or whole otoliths, compared to records on the otolith slices through the tubercle. An exploitation strategy based on improper age determination can have a negative impact on the state of the greenland halibut stock, in combination with natural causes, or even be a major reason of this species depression.

Effect of sea cage aquaculture on the length, weight, and condition of wild Atlantic cod Gadus morhua

Wild fish have been shown to associate with sea cage aquaculture and consume waste feed; however, little is known about the effects of waste feed consumption on wild fish. We used Atlantic cod Gadus morhua collected in the direct vicinity of sea cages and reference Northwest Atlantic Fisheries Organization divisions, either outside the direct vicinity (‘local division’) or completely removed from aquaculture (‘outside divisions’), to compare length, weight, and condition for cod ages 2 to 4. Concentrations of vegetable oil-based fatty acids (linoleic acid and α-linolenic acid) were then used as biomarkers for waste feed consumption to determine their role in explaining differences in length, weight, and Fulton’s condition index among cage-associated cod. Age 2 cage-associated cod were in lower condition than age 2 cod from the local division and lighter than age 2 cod from all outside divisions. Age 3 cage-associated cod were comparable to age 3 cod from the local division but in lower condition than age 3 cod from all outside divisions. However, age 4 cage-associated cod were longer and heavier than age 4 cod from the local division, but in lower condition than age 4 cod from 2 of 3 outside divisions. Additionally, there were positive relationships between fatty acid concentrations and length and weight for age 2 cage-associated cod, but no significant relationships for age 3 or 4 cage-associated cod. Results suggest the effects of waste feed consumption are contradictory but not consistent enough to disrupt established growth and condition patterns among divisions.

Identifying possible drivers of the abrupt and persistent delay in capelin spawning timing following the 1991 stock collapse in Newfoundland, Canada

Abstract Spawning timing in fish is generally cyclical in temperate regions in order to increase the probability of matching larval occurrence with ideal environmental conditions. The capelin stock in Northwest Atlantic Fisheries Organization Divisions 2J3KL collapsed in 1990–1991 and has not recovered. This collapse was concomitant with collapses in groundfish stocks and cold oceanographic conditions. Using citizen science data, newspaper archives, grey and primary literature, and monitoring data, a century of capelin beach spawning times were compiled. Capelin beach spawning has been persistently 3 weeks later since the stock collapse. To identify potential predictors of capelin spawning timing, an exploratory analysis was conducted using environmental and biological variables and a period factor that categorized a year as either pre-collapse (1990 and earlier) or post-collapse (post-1990) in a step-wise multiple regression model. Spawning timing was predicted to be delayed in the post-collapse period when there were negative anomalies in the Newfoundland and Labrador Climate Index and summer (June–August) North Atlantic Oscillation, and when there was a decrease in mean length of the spawning population. The production of weak year-classes is predicted when spawning is delayed, suggesting that late spawning is severely inhibiting the recovery of the stock.

Further Analysis of Clockwise Loops and Anticlockwise Loops Observed in a Stock-Recruitment Relationship

Loop-shaped trajectories are commonly observed in the stock-recruitment relationship (SRR). A mechanism that explains why the loops emerge in SRR has been proposed, and the aim of this study was to validate this mechanism using 62 stocks that live in the waters around Japan, the Northwest Atlantic Fisheries Organization area, and elsewhere. We discuss the relationship between the age at maturity and the slope of the regression line adapted for the SRR data. Further, we discuss whether or not the age at maturity determines whether clockwise or anticlockwise loops are dominant. The results were as follows: 1) The slopes of the regression line adapted for the SRR had positive values when the age at maturity was low. As the age at maturity increased, the slopes decreased to zero and then became negative values. As the age at maturity increased even further, the slopes again changed from negative values to zero and then from zero to positive values. 2) Clockwise loops were dominant when the age at maturity was low, and anticlockwise loops were dominant when the age at maturity was high. As the age at maturity increased even more, clockwise loops again became dominant. These findings coincide well with the results presented by Tanaka et al. In the past, a density-dependent effect has been considered to be the main factor driving the fluctuations, but the present results indicated that a different mechanism may control the SRR and the fluctuations in the population.

Evidence of near year-around spawning in Atlantic cod off southern Newfoundland: implications for management

Management of Atlantic cod (Gadus morhua) off southern Newfoundland (Northwest Atlantic Fisheries Organization (NAFO) Subdivision 3Ps) entails allocated quotas and restrictions on fishing during late winter and springtime to protect presumed spawning aggregations. We present data collected from research trawls and handlines (1995–2014) indicating spawning inshore may occur near year-around with limited resting from December to February and with more contracted spring spawning possible offshore. A mixed general linear model with binomial error, using year as a random factor, recognized month and length as significant impacts on proportions of females spawning, but not gear or inshore–offshore location. Composite data indicated that females in spawning condition may be present inshore (∼10%–20% of adult females) from March to October. During 1997–1999, with 8–9 months sampled each year, protracted annual spawning schedules and interannual variability were evident. At present, the fishery primarily employs gillnets inshore and otter trawls offshore, with spring spawning closures offering only partial and inconsistent protection. Behavioural interference might be reduced by employing less intrusive longlines, as historically practiced in this fishery.

Climate-change impacts and fisheries management challenges in the North Atlantic Ocean

Climate-induced changes in the world’s oceans will have implications for fisheries productivity and management. Using a model ensemble from the Fisheries and Marine Ecosystem Model Intercomparison Project (Fish-MIP), we analyzed future trajectories of climate-change impacts on marine animal biomass and associated environmental drivers across the North Atlantic Ocean and within the Northwest Atlantic Fisheries Organization (NAFO) convention area and evaluated potential consequences for fisheries productivity and management. Our ensemble results showed that the magnitude of projected biomass changes increased over time and from a low (RCP2.6) to high (RCP8.5) emissions scenario. Within individual NAFO divisions, however, projected biomass changes differed in the magnitude and sometimes direction of change between near (the 2030s) and far future (the 2090s) and contrasting emissions scenarios. By the 2090s, most NAFO divisions with historically (1990-1999) high fisheries landings were projected to experience biomass decreases of 5-40%, while Arctic and subarctic divisions with lower historical landings were projected to experience biomass increases between 20 and 70% under RCP8.5. Future trajectories of sea surface temperature and primary production corroborated that the far-future, high-emissions scenario poses the greatest risk to marine ecosystems and the greatest challenges to fisheries management. Our study summarizes future trends of marine animal biomass and underlying uncertainties related to model projections under contrasting climate-change scenarios. Understanding such climate-change impacts on marine ecosystems is imperative for ensuring that marine fisheries remain productive and sustainable in a changing ocean.

Analysis of EU Membership in the Northwest Atlantic Fisheries Organization (NAFO) as a Specific Model for EU Relations with International Intergovernmental Organizations

The article falls into the complicated and only partially analysed issues related to the essence of relations between international intergovernmental organizations. Against a background of the typology taking into account the scope and nature of EU representation in international intergovernmental organizations, it addresses the most important issues related to the essence of relations between the EC/EU and NAFO. Therefore, it discusses such matters as: the evolution of NAFO in the years 1979–2017, the nature of EU membership in NAFO, matters related to the representation and implementation of EC/EU interests on NAFO forum, as well as the system of internal coordination of EU activities in connection with its membership in this organization.

Illegal, Unreported, and Unregulated Fisheries: The Northwest Atlantic Fisheries Organization Experience

Illegal, Unreported, and Unregulated Fisheries: The Northwest Atlantic Fisheries Organization Experience

Seabed litter distribution in the high seas of the Flemish Pass area (NW Atlantic)

Seabed litter of the Flemish Pass area (NW Atlantic Ocean) was analysed and described using data from the EU-Spain groundfish survey (2006-2017 period). This study presents baseline information on seabed litter in this area. The Flemish Pass is located in areas beyond national jurisdiction within the Northwest Atlantic Fisheries Organization Regulatory Area Division 3L. A total of 1169 valid bottom trawl hauls were analysed (104-1478 m depth). Litter was found in 8.3% of the hauls, with mean densities of 1.4±0.2 items km–2 and 10.6±5.2 kg km–2. An increasing pattern with depth was found, the highest densities of seabed litter being identified in the deepest areas located in the Flemish Pass channel and down the northeastern flank of the Grand Bank. Fishing was found to be the main source of marine litter, and 61.9% of the hauls with litter presence showed litter included in the fisheries-related litter category. Whereas in most cases the litter was composed of small fragments of rope, in other cases it was composed of entire fishing gears such as traps. Plastics, metal and other anthropogenic litter were the next most abundant categories, accounting for 18.6%, 16.5% and 12.4% of the total, respectively.

Removal of deep-sea sponges by bottom trawling in the Flemish Cap area: conservation, ecology and economic assessment

Deep-sea sponge grounds are vulnerable marine ecosystems, which through their benthic-pelagic coupling of nutrients, are of functional relevance to the deep-sea realm. The impact of fishing bycatch is here evaluated for the first time at a bathyal, sponge-dominated ecosystem in the high seas managed by the Northwest Atlantic Fisheries Organization. Sponge biomass surface created from research survey data using random forest modeling revealed 231,136 t of sponges in the area. About 42% of that biomass was protected by current fisheries closures. However, projections of trawling tracks estimated that the sponge biomass within them would be wiped out in just 1 year by the current level of fishing activity if directed on the sponges. Because these sponges filter 56,143 ± 15,047 million litres of seawater daily, consume 63.11 ± 11.83 t of organic carbon through respiration, and affect the turnover of several nitrogen nutrients, their removal would likely affect the delicate ecological equilibrium of the deep-sea benthic ecosystem. We estimated that, on Flemish Cap, the economic value associated with seawater filtration by the sponges is nearly double the market value of the fish catch. Hence, fishery closures are essential to reach sponge conservation goals as economic drivers cannot be relied upon.

Cold-water corals and deep-sea sponges by-catch mitigation: Dealing with groundfish survey data in the management of the northwest Atlantic Ocean high seas fisheries

The integration of survey data in the processes of the Regional Fisheries Management Organisations is a key step for conservation of deep-sea ecosystems and sustainable exploitation of deep-sea fisheries resources, including the mitigation of by-catch and discards of cold-water corals and deep-sea sponges, both considered by FAO as vulnerable marine ecosystems (VMEs) indicator species. Information on corals and sponges from annual bottom trawl groundfish surveys in areas beyond national jurisdictions has been integrated into the “ecosystem management cycle” of the Northwest Atlantic Fisheries Organization (NAFO). Survey data have improved our knowledge on VMEs identification, distribution and extent, and has led to the proposal and implementation of conservation and management measures. These data have particular relevance to delineate and refine the boundaries of areas closed to commercial bottom fishing (14 closures), in order to prevent significant adverse impacts on VMEs, according to the mandate of United Nations General Assembly Resolution 61/105. Considering the European groundfish surveys in the NAFO Regulatory Area (high seas) as a case study, the paper presents an overview of how invertebrate catch data have been integrated into the fisheries management process as a basis to the implementation of VMEs closed areas. Fishing closures are considered effective spatial management measures to avoid by-catch and discards of cold-water corals and deep-sea sponges in commercial bottom fishing, mitigating the adverse impacts on deep-sea ecosystems.

On the Influence of Vulnerable Marine Ecosystem Habitats on Peracarid Crustacean Assemblages in the Northwest Atlantic Fisheries Organisation Regulatory Area

Vulnerable marine ecosystems (VMEs) are considered hotspots of biodiversity and ecosystem functioning in the deep sea, but are also characterised by a high vulnerability to disturbance and a low recovery potential. Since 2006, a series of United Nations General Assembly resolutions have been developed, attempting to ensure the protection of VMEs in international waters. In the Northwest Atlantic Fisheries Organisation (NAFO) Regulatory Area, large areas of seabed have been closed to bottom-contact fishing to protect VMEs. However, knowledge of the influence of VME-indicator taxa on macrofaunal assemblages, and the appropriateness of current fishery closures for protecting macrofaunal biodiversity in this area is limited. Here we investigate relationships between the prevalence of VME-indicator taxa (poriferans [sponges], gorgonian corals and pennatulaceans [sea pens]) and an extensive suite of peracarid crustacean biodiversity metrics in the NAFO Regulatory Area. We also examine whether the current NAFO VME closures protect areas of significantly elevated peracarid diversity. Of the VME-indicator taxa analysed, poriferans were found to have by far the greatest influence over peracarid assemblages. Assemblage structure was altered, and peracarid abundance, biomass, richness, diversity, and variability were enhanced in areas of elevated poriferan biomass, whilst assemblage evenness was slightly depressed in these areas. These findings reaffirm the perception of poriferans as crucial components of VMEs. In contrast, gorgonian coral density had little influence over the faunal assemblages investigated, perhaps reflecting their relatively low prevalence in the study area. Similarly, pennatulaceans were found to influence peracarid assemblages only weakly. This too may reflect a moderately low density of Pennatulacea in the study area. Our results highlight that the application of taxon distribution model outputs to ecological investigations and management decisions in data-limited environments should be treated with caution. Finally, our results indicate that the current system of fishery closures in the NAFO Regulatory Area may not be optimal in terms of providing adequate protection to VMEs against the impacts of bottom trawling.

The Northwest Atlantic Fisheries Organization Roadmap for the development and implementation of an Ecosystem Approach to Fisheries: structure, state of development, and challenges

The Northwest Atlantic Fisheries Organization (NAFO) Roadmap is the general framework aimed toward implementing an Ecosystem Approach to Fisheries (EAF) in NAFO. The core principles are: a) the approach has to be objective-driven, b) it should consider long-term ecosystem sustainability, c) it must be place-based, and d) the consequences of trade-offs in managing human activities have to be explicitly defined. The Roadmap is not a fixed plan; it evolves as different components are developed, refined, and implemented. Core elements of the Roadmap include the identification of ecosystem-based management units, a hierarchical approach to define exploitation rates by considering ecosystem, multispecies, and stock level sustainability, and the integration of impacts on benthic communities. The modular design of the plan has allowed NAFO to start implementing some components (e.g. closures to bottom fishing for the protection of Vulnerable Marine Ecosystems), while work on others is still ongoing (e.g. multispecies modelling). Even though the Roadmap is far from being fully implemented, NAFO has made important progress towards EAF over the last decade. This paper summarizes the Roadmap structure and the current level of implementation, describes some of the challenges faced, and examines those still ahead.

Connectivity modelling of areas closed to protect vulnerable marine ecosystems in the northwest Atlantic

Over the course of the past decade, in response to United Nations General Assembly resolutions calling for the protection of vulnerable marine ecosystems (VMEs), the Northwest Atlantic Fisheries Organization has closed 14 areas around the high-seas portion of Grand Bank and Flemish Cap to protect deep-sea coral and sponge habitats from impacts by bottom-contact fishing gears. Structural and functional connectivity for those areas were not explicitly considered in the area-selection process. We applied a particle-tracking model in each of four seasons to produce dispersal trajectories at the surface and 100 m from start points within the closed areas. These were run in forecast and hindcast modes to identify dispersal kernels. Currents at the surface, 100 m, 1000 m and “on bottom” were examined under an independent model (NEMO) to infer structural connectivity among the areas at relevant depths not available in the particle-tracking model. Spawning times and planktonic larval duration of the dominant sponges, sea pens and gorgonian corals were then considered to evaluate the trajectories as bio-physical models, while species distribution models identified potential source populations from hindcast projections. Five of the 14 areas, including the three largest closures, showed particle retention, with three others showing retention within 10 km of their boundaries. The regional pattern of currents and their topographic forcing emerged as a strong structuring agent. A system of weakly-connected closed areas to protect sea pen VMEs on Flemish Cap was identified. The conducted approach illustrates the added value of assessing/modelling networking properties when designing MPAs.

Recruitment synchrony in spatially structured Newfoundland and Labrador populations of American plaice (Hippoglossoides platessoides)

Appropriate stock delineation is one of the fundamentals for reliable stock assessment. Investigating stock delineation is not a common practice on regularly assessed stocks, yet it is highly desirable prior to extensive investment into new assessment approaches for a stock. Recruitment correlations are an important determinant of stock boundaries, and in this paper, we investigate these correlations between American plaice stocks/components in the Northwest Atlantic Fisheries Organization (NAFO) Divisions 2J3KLMNOPs. Currently, American plaice in 2J3K are managed as part of the Labrador and the northeast coast of Newfoundland stock, 3LNO as the Grand Bank stock, and sub-Division 3Ps as the St Pierre Bank stock. We estimated mixed-effect cohort-strength models using abundance indices from Canadian Research Vessel (RV) surveys conducted every year in the spring (3LNOPs) and fall (2J3KLMNO) and investigated the correlation in the recruitment patterns of American plaice in these NAFO divisions. We performed cluster analysis to assess if the estimated correlations are consistent with the current stock delineations. We further explored causative/correlative relationships between spawning stock biomass (SSB), temperature, and recruitment. Our analyses supported the separation of the 2J3K northeast coast stock from the Grand Bank (3LNO) and St Pierre (3Ps) stocks. Our analysis showed strong synchrony in recruitment patterns between the 3LNO and 3Ps regions indicating either interactions in American plaice populations between the Grand Bank and St Pierre stocks, or strong environmental influences on recruitment success that affect both stocks similarly. Our analyses of recruitment correlations with SSB and temperature did not indicate strong associations except for significant correlations between recruitment and SSB between 3L and 3Ps.

Could population and community indicators contribute to identify the driver factors and describe the dynamic in the Flemish Cap demersal assemblages?

Flemish Cap is an isolated fishing ground located in the international waters of the Northwest Atlantic Fisheries Organization area (NAFO). In the last decades, the Flemish Cap demersal community has been subjected to strong and variable fishing intensities affecting different stocks over time. In this work, three ecological indices for individual populations (abundance, biomass, and intrinsic population rate of growth) and five community indicators (total abundance and biomass, community synchrony, ABC curves and proportion of non-commercial/commercial species) have been applied to data of 29 fish and 1 shrimp species to analyse the dynamics of the whole ecosystem and the major demersal fish assemblages. Different periods were detected, which may be explained by differences in the exploitation patterns and pressure for different stocks, prey-predators relationships and other environmental drivers affecting the reproductive capacity. This study shows that the selected community indicators are appropriate to detect changes in the demersal community of Flemish Cap in response to fishing, predation and variability in recruitment success. It has been also demonstrated that treating each depth zone separately help us to better understand trends and that analyses revealed different trends for different parts of the community during periods with different fishing pressure. This knowledge could be useful to support management policies.

Birla to supply carbon black to Linglong

Case studies of the Canada Department of Fisheries and Oceans (DFO), Northwest Atlantic Fisheries Organization (NAFO), and the Food and Agriculture Organization of the United Nations (FAO) highlighted factors influencing scientific communication that are contingent on the characteristics of the many dynamic and iterative science-policy interfaces among decision-makers, scientists, and other stakeholders. Direct observations of 15 scientific and management meetings coupled with interviews with 78 scientists and managers revealed aspects of the information pathways, i.e., production, communication, and use of scientific information in these organizations. Unique features of decision-making and information use enable the production of credible, relevant, and legitimate information in each organization, including trade-offs in these attributes to support fisheries governance objectives. For instance, defined processes for producing scientific advice embedded in fisheries management authorities, such as DFO and NAFO, ensure uptake of information in decision-making. As a boundary organization, FAO bridges science and policy-making groups among its member countries. The demand for scientific advice, policy development, and trade aspects are primary drivers in the information pathways. However, organizational aspects such as dispersed units and inadequate communication persist as barriers to information flow. Across the geographic scales of the three organizations, stakeholders apart from government scientists and policy-makers, e.g., the fishing industry, non-governmental organizations (NGOs), and the public, are increasingly involved in the information pathways. Insights about the information pathways can equip the organizations to evaluate or modify practices to increase the uptake of information in decision-making as fisheries management issues and considerations become more complex.