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Mesopelagic fish are considered a possible future fisheries resource, but the biological sustainability of their potential exploitation has not yet been assessed. Sustainability should be evaluated at the population level, for which accurate stock-specific life-history parameters are required. Here, we use a length-based model to estimate life-history parameters related to growth and natural mortality, and their uncertainty, for the assessment of Northeast Atlantic populations of Maurolicus muelleri (Gmelin, 1789, Mueller’s Pearlside) and Benthosema glaciale (Reinhardt, 1837, glacier lantern fish). We compare three different approaches to estimate natural mortality rates and provide recommendations for future data collection and monitoring programs. For M. muelleri, we estimated an asymptotic length of 57.98 mm and a von Bertalanffy growth constant of 1.28 year−1, while for B. glaciale, we estimated an asymptotic length of 78.93 mm and a von Bertalanffy growth constant of 0.41 year−1. Estimates of natural mortality rates for M. muelleri were around 1.29 year−1 and 1.80 year−1 based on empirical formulae with the estimated growth parameters and maximum age, respectively, and around 1.51 year−1 with the length-converted catch curve method for B. glaciale estimates ranged between 0.5, 0.68, and 0.75 year−1, with the three respective methods. Due to limited data availability, the estimated uncertainty of the provided life-history parameters is large and should be considered in the evaluation of the sustainability of potential mesopelagic exploitation following the precautionary approach.

The worldwide disruption caused by the beginning of the COVID-19 pandemic has dramatically impacted the activities of marine scientists working towards the goals of the UN Ocean Decade. As in other disciplines, marine early-career researchers (ECRs) are essential contributors to the development of novel and innovative science. Based on a survey of 322 of our peers, we show that the pandemic negatively impacted marine ECRs in ways that further exacerbate existing structural challenges such as social isolation, job insecurity, and short-term contracts, competitive funding, and work pressure. Furthermore, we find that the success and wellbeing of marine ECRs depends heavily on networking opportunities, gaining practical experience, collecting data, and producing publications, all of which were disrupted by the pandemic. Our analysis shows that those in the earliest stages of their careers feel most vulnerable to long-term career disadvantage as a result of the pandemic. This paper contributes to the empirical body of work about the impacts of the pandemic on marine science and offers recommendations on how marine ECRs should be supported to achieve the UN Ocean Decade’s goal of producing “the science we need for the ocean we want”.

Environmental DNA (eDNA) comprises intra- and extra-cellular DNA molecules that are released in the environment and can be traced back to the source organism by analysing an environmental sample, such as water or sediment. While many limitations still exist, the coupling and integration of eDNA sampling with both traditional methods (direct capture) and/or other non-invasive approaches (imaging and acoustic data) has great potential to enhance monitoring capabilities of the marine environment. In addition, emerging technologies (including portable sequencers) are enabling the development of protocols for near real-time in situ applications of eDNA analysis. Our aim is to develop, test and implement eDNA metabarcoding protocols capable of being installed onto marine platforms such as marine fixed or mobile infrastructures (e.g. fixed observatories, platforms, research vessels) to provide real-time data of support to fisheries and other megafauna monitoring programs. An initial protocol has been already tested in laboratory conditions using a MinION portable sequencer (Oxford Nanopore Technologies), with preliminary results showing promising results in generating fish community profiles from eDNA samples collected at depth along the Northeast Atlantic continental shelf. Furter protocol development is ongoing and will include complete processing of environmental samples, from collection to High Throughput Sequencing (HTS) and bioinformatic analysis, in remote conditions. Specifically, results of protocol validation and implementation will be presented after execution in three contexts: (i) an aquarium with known species richness (Galway Atlantaquaria, Ireland); (ii) an open water fixed observatory equipped with a full suite of sensors including video (the Acqua Alta platform (Northern Adriatic Sea, Italy)); and (iii) offshore on board a research vessel during acoustic fisheries surveys (the Marine Institute's RV Celtic Explorer, Ireland). The inclusion of eDNA in the m

Background The field of behavioural economics holds several opportunities for integrated fisheries management and conservation and can help researchers and managers alike understand fisher behaviour and decision-making. As the study of the cognitive biases that influence decision-making processes, behavioural economics differentiates itself from the classical field of economics in that it does not assume strictly rational behaviour of its agents, but rather looks for all mechanisms that influence behaviour. This field offers potential applications for fisheries management, for example in relation to behavioural change, but such applications require evidence of these mechanisms applied in a fisheries context. Thus, we have developed a systematic literature review protocol focusing on the primary question: “Which behavioural economics mechanisms influence fisher behaviour?” The aim is to provide a comprehensive overview of these different mechanisms and how they have been applied in the study of fisher behaviour. Methods and expected outputs The review protocol was developed in close collaboration with the International Council for the Exploration of the Sea (ICES) Working Group on Maritime Systems (WGMARS). WGMARS members were therefore considered the key stakeholders for this study, and were consulted to develop a suitable systematic review question and methodology. Three academic databases will be searched using a customized Boolean keyword search string. Research articles deemed eligible for inclusion in the systematic review are those that studied the influence of behavioural-economics mechanisms on the behaviour of marine fishers in any location, and at any scale. Insights from this literature will be collated in order to provide an overview of the relevant behavioural-economics mechanisms and actions, how effective these mechanisms are and at what scale, geographic region and in which fisheries sector they have been applied. Any fisheries management implication