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Simple Summary: The Norway lobster is a key species for European Atlantic and Mediterranean fisheries. We performed a global bibliographic survey using the VOSviewer software to investigate the status of research on Norway lobsters by extracting data from all relevant scientific literature published in SCOPUS since 1965. The analysis revealed three clusters: (1) fishery performance, stock assessment, and management; (2) biological cycles in growth, reproduction, and behavior; and (3) physiology and ecotoxicology (including food products). Intense research has emerged on ecotoxicology and fishery management (which also includes other commercially targeted and co-existing species). Finally, earlier studies generally focused on the morphological and physiological aspects of this species while more recent studies have focused on fisheries and on Norway lobster as a food resource. In summary, the results indicate that knowledge is scarce on how the burrowing behavior of N. norvegicus is influenced by environmental conditions and how this affects stock assessments. We attribute this to limited use of current and advanced monitoring technologies. The burrowing crustacean decapod Nephrops norvegicus is a significant species in European Atlantic and Mediterranean fisheries. Research over the decades has mainly focused on behavioral and physiological aspects related to the burrowing lifestyle, since animals can only be captured by trawls when engaged in emergence on the seabed. Here, we performed a global bibliographic survey of all the scientific literature retrieved in SCOPUS since 1965, and terminology maps were produced with the VOSviewer software to reveal established and emerging research areas. We produced three term-map plots: term clustering, term citation, and term year. The term clustering network showed three clusters: fishery performance, assessment, and management; biological cycles in growth, reproduction, and behavior; and finally, physiology and ecotoxicology, including food products. The term citation map showed that intense research is developed on ecotoxicology and fishery management. Finally, the term year map showed that the species was first studied in its morphological and physiological aspects and more recently in relation to fishery and as a food resource. Taken together, the results indicate scarce knowledge on how burrowing behavior and its environmental control can alter stock assessment, because of the poor use of current and advanced monitoring technologies. [ABSTRACT FROM AUTHOR]

The International Council for the Exploration of the Sea (ICES) has provided scientific stock advice based on reference points to manage fisheries in the North Atlantic Ocean and adjacent seas for decades. ICES advice integrates the precautionary approach with the objective of achieving maximum sustainable yield. Here, we examine ICES reference point evolution over the last 25 yr and provide a comprehensive empirical review of current ICES reference points for data-rich stocks (Category 1; 79 stocks). The consistency of reference point estimation with the ICES guidelines is evaluated. We demonstrate: (1) how the framework has evolved over time in an intergovernmental setting, (2) that multiple precautionary components and sources of stochasticity are included, (3) that the relationship and historical context of stock size and recruitment are crucial for non-proxy reference points, (4) that reference points are reviewed frequently, taking into account fluctuations and multiple sources of variability, (5) that there are occasional inconsistencies with the guidelines, and (6) that more comprehensive and clearer documentation is needed. Simplifying the stock-recruit typology and developing quantitative criteria would assist with this critically important classification. We recommend a well-documented, transparent, and reproducible framework, and periodic syntheses comparing applications across all stocks. [ABSTRACT FROM AUTHOR]

For many environmental indicators, the sustainable status can change because of changes in either the monitored state or the policy goal. Fisheries provide an intensively monitored setting to investigate the relative impacts of such change. Key fisheries sustainability indicators comprise the ratio between fishing pressure or biomass and their respective reference levels. We developed a retrospective database of population status, reference point changes and reported reasons for changes for all data‐rich stocks in the ICES region. We derived methods to distinguish the impacts of either source of change (monitored state or policy goal) on sustainable status. We found that reference points changed frequently (64% of populations had reference point changes) with varying magnitudes. Contrary to expectation, reference point changes were often not compensated by changes in the state thus significantly impacting inferred sustainability status and dependent scientific advice. Across a range of life histories and assessments, changes in reference points dominate retrospective revisions in status over the full time series. Overall, status before and after the change of reference point had no significant directional differences that would suggest reference point change effecting movement towards or away from sustainability. Although multiple factors have contributed to reference point changes, our results show that the reference point definition and the technical basis for estimation were the most important reasons for change. Recognizing that reference points are not constant in time but rather form reference series is paramount to quantifying present and historical sustainability. Properly documenting, justifying and quantifying the impacts of such change is an ongoing challenge. [ABSTRACT FROM AUTHOR]

Theoretical size at the onset of maturity (TSOM) for female Norway lobster was estimated by a new methodology based on the probability distributions of mature individuals built on physiological maturity measures. Onset of maturity using TSOM varied from 18.4- to 33.7-mm carapace length for the Irish functional management units (FUs). These estimates showed a significant negative linear relationship (R 2 = 0.60) with population density and a significant positive linear relationship with average size in females (R 2 = 0.84). The size class at which 50% of the females are sexually mature (L 50) was linked to the new TSOM metric by a significant positive linear relationship (R 2 = 0.40). This set of linear relationships ultimately allowed TSOM and L 50 to be estimated without a requirement for maturity stages to be distinguished. As well as contributing to the stock assessment and management of Nephrops (e.g. in data-limited FUs) and its potential for the calibration of more routinely used estimates, TSOM might be applied in new species and meta-analyses where size of maturity data are scarce. This new metric also better-defines the maturity process since, taken together, TSOM, L 50, and smallest berried female represent sequential maturity events: (i) onset of maturity, (ii) 50% mature (from gonad staging), and (iii) berried females. [ABSTRACT FROM AUTHOR]

Because environmental temperature has an important influence on developmental rate and physiology, marine ectotherms are vulnerable to phenology changes due to ocean warming. Identifying changes to phenology, the timing of biological events, and understanding their effect on recruitment and abundance is of critical importance to establish potential population effects. We examined the larval phenology of the commercially important Norway lobster (Nephrops norvegicus) and used a larval transport model to examine its effect on simulated transport patterns. Using a model to estimate annual larval release dates based on temperature‐dependent embryo incubation, an earlier shift of 17.2 d occurred between 1982–1995 and 2000–2010 in the Irish Sea, similar to an observed empirical shift in phenology of 19.1 d using historical zooplankton data sets. Despite this earlier phenology, temperature‐dependent pelagic larval durations were unchanged because the water column to which larvae were released earlier had also warmed. Larval transport simulations in the western Irish Sea indicated that the phenology shift had minimal effects on larval retention and advection distance overall, because major variations were observed only at very early or late stages of the larval season, that is, times when lower proportions of larvae were present. As the western Irish Sea grounds exports small but consistent quantities of larvae to nearby populations, especially off Scotland, it may act as an important source of larvae, especially when retention of native larvae is low. Overall, larval transport tools may indicate grounds that are periodically vulnerable to recruitment failures and offer potentially valuable information in fishery management. [ABSTRACT FROM AUTHOR]

Knowledge of the spatial distribution and habitat associations of species in relation to the environment is essential for their management and conservation. Habitat suitability models are useful in quantifying species-environment relationships and predicting species distribution patterns. Little is known, however, about the stability and performance of habitat suitability models when projected into new areas (spatial transferability) and how this can inform resource management. The aims of this study were to model habitat suitability of Norway lobster (Nephrops norvegicus) in five fished areas of the Northeast Atlantic (Aran ground, Irish Sea, Celtic Sea, Scotland Inshore and Fladen ground), and to test for spatial transferability of habitat models among multiple regions. Nephrops burrow density was modelled using generalised additive models (GAMs) with predictors selected from four environmental variables (depth, slope, sediment and rugosity). Models were evaluated and tested for spatial transferability among areas. The optimum models (lowest AICc) for different areas always included depth and sediment as predictors. Burrow densities were generally greater at depth and in finer sediments, but relationships for individual areas were sometimes more complex. Aside from an inclusion of depth and sediment, the optimum models differed between fished areas. When it came to tests of spatial transferability, however, most of the models were able to predict Nephrops density in other areas. Furthermore, transferability was not dependent on use of the optimum models since competing models were also able to achieve a similar level of transferability to new areas. A degree of decoupling between model ‘fitting’ performance and spatial transferability supports the use of simpler models when extrapolating habitat suitability maps to different areas. Differences in the form and performance of models from different areas may supply further information on the processes shaping species’ distributions. Spatial transferability of habitat models can be used to support fishery management when the information is scarce but caution needs to be applied when making inference and a multi-area transferability analysis is preferable to bilateral comparisons between areas. [ABSTRACT FROM AUTHOR]

Abstract: The Irish otter trawl fleet operates in a complex multi-species multi-gear fishery, spanning a wide geographic area, and involving around 275 trawlers. Factorial and clustering methods were applied to 2003 fishing trip data to define thirty-three métiers. Definitions were based on six trip characteristics taken from logbooks, namely: fishing gear, mesh size, vessel length, species composition, area, and month. Métiers exploiting demersal species or species groups are characterised by single vessel bottom otter trawls, typically with mesh sizes of 70mm or more, operating year round. This includes nine Nephrops dominated métiers highlighting the importance of this species to the fleet. Many demersal métiers are characterised by groups of species, such as mixed whitefish or slope species. Métiers exploiting pelagic species are often focussed on single species, and are typically seasonal, mid-water trawling (often paired) with mesh sizes less than 70mm. Pelagic métiers account for the majority of landings by over an order of magnitude in several cases. Demersal métiers account for the majority of fishing trips and effort, (primarily Nephrops métiers), and vessels (primarily mixed species métiers). The new métier definitions were found to be appropriate remained relevant despite declining fleet landings and effort between 2003 and 2006. Species compositions within these métiers have generally remained similar to the proportions defined in 2003. These robust métier definitions present opportunities to improve fisheries sampling, assessment and management. Although métiers pose complexity challenge for such applications they can be used the building blocks for appropriate management units. [Copyright &y& Elsevier]

Davie, S., and Lordan, C. 2011. Examining changes in Irish fishing practices in response to the cod long-term plan. – ICES Journal of Marine Science, 68: 1638–1646.In 2009, there were marked changes in Irish demersal fishing effort owing to the implementation of a new cod long-term plan (CLTP). This replaced previous top-down cod recovery plans, first implemented in 2002, that set days-at-sea limits for fishing vessels. The new plan specifies a harvest control rule, annual effort ceilings for EU Member States, and rules for adapting fishing effort. It encourages cod avoidance, but leaves Member States to allocate effort between individual vessels. During 2009, effort was allocated through a series of pilot schemes in Ireland. These can be considered as an evolution towards co-management. Industry and state authorities worked closely together to develop strategies for effort management and cod avoidance. The impact of recent effort-management measures on the Irish fleet, fishery, and métiers affected by the CLTP is evaluated. Vessel movements within and between métiers are described and discussed, and unintended impacts resulting from the implementation of management schemes are highlighted. In future, possible fishers' responses to policy initiatives should be considered prior to implementation to minimize potentially adverse consequences. [ABSTRACT FROM PUBLISHER]

Lordan, C., Ó Cuaig, M., Graham, N., and Rihan, D. 2011. The ups and downs of working with industry to collect fishery-dependent data: the Irish experience. – ICES Journal of Marine Science, 68: 1670–1678.Working with the fishing industry to collect fishery-dependent data for scientific and advisory purposes is essential in most countries, but despite the many advantages of working with fishers, it is not without challenges. The objectives and the ups and downs of 16 recent projects in Ireland are described, and four case studies are discussed in detail. Some common themes that characterize both successful and unsuccessful experiences are identified. One critical aspect is industry's sometimes unrealistic time-horizons and expectations when engaging in scientific data collection. Detailed communication of objectives, procedures, results, and relevance not only to industry representatives, but also to vessel owners and crew, is required throughout the life cycle of a project. For some projects, there is a clear need to include incentives in the design, but for others this is less critical. The critical needs for ongoing quality control and assurance, validation of data, and appropriate project design are discussed, along with the link between successful management systems and participatory research. Finally, comment is provided on how the expected reforms of the EU's Common Fisheries Policy will place new demands on joint research. [ABSTRACT FROM PUBLISHER]

Rihan, D., Graham, N., Reid, D. G., and Lordan, C. 2011. The provision of fishery information by ICES–WGFTFB to assessment working groups: use of information and lessons learned. – ICES Journal of Marine Science, 68: 1809–1814.ICES is now asked to provide advice that is more holistic in nature, including information on the influence and effects of human activities on the marine ecosystem. From a fishing-technology perspective, this includes information on how fishers respond and adapt to changes in regulatory frameworks, the impact of technology creep, ecosystem impacts, and changes in fleet dynamics. Recognizing the importance of this, in 2005, the ICES–Food and Agriculture Organization (FAO) Working Group on Fish Technology and Fish Behaviour (WGFTFB) began to collect data and information to support scientific advice on fisheries and ecosystem issues through a questionnaire circulated to its members. The information from the questionnaires was collated by the WGFTFB and submitted in the form of summary documents to various ICES assessment working groups. This paper describes the background to this initiative, the questionnaire structure, the type of information provided, and its utility. [ABSTRACT FROM PUBLISHER]

There is growing international focus on ecosystem based fisheries management. Within the EU this has manifested in the provision of mixed fisheries advice, using the FCube model. The operational implementation and accuracy of this model relies on accurate identification of the technical interactions between fleets, gears and the resulting composition of species in the retained catch. These interactions are defined using units of fishing activity based on gear type and target species assemblage, but with no consideration for spatiotemporal heterogeneity. We assess the relevance of the fishing units used in relation to the spatial and temporal trends in retained catch within the Celtic Sea. To achieve this multivariate analysis (principal component and hierarchical clustering) were conducted to identify homogenous groupings of fishing activity using 5 years of international Celtic Sea retained catch data. The groupings identified demonstrate that a fairly simplistic structure of fishing activity units (country of provenance, fishing location, gear and target species) can effectively describe the complex mixed fisheries scenarios being executed within the Celtic Sea consistently across multiple years. This international and multiannual analysis improves our understanding of the mixed fisheries scenarios within the Celtic Sea and reveals a multifaceted spatial structure in the species assemblages landed, indicating the presence of several distinct mixed fisheries within the region appropriate for mixed fisheries analyses. [ABSTRACT FROM AUTHOR]