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Deep-water sharks are highly diverse, vulnerable, and understudied as a group, despite the increasing pressures on their populations. Twenty-five species of deep-water sharks have been recorded in the Azores, an oceanic archipelago in the mid-North Atlantic, that are regularly caught as bycatch in hook-and-line fisheries. Avoiding the bycatch of deep-water sharks presents multiple challenges due to their high catchability, difficulties in correctly identifying species, and the general lack of data on these species. This review summarizes the findings of recent studies from the region, providing an up-to-date science-based framework for mitigating bycatch effects of Azorean hook-and-line fisheries. Several depth-based, area-based, and gear-based measures have been studied that demonstrate the potential to either avoid or increase the survival of deep-water shark bycatch. However, these measures may have limited efficacy for some species (e.g. highly mobile species) and thus, limited widespread applicability. Convincing fishers to avoid deep-water shark bycatch is also a challenge given the antagonistic interactions with sharks damaging the catch and fishing gear, while simultaneously a market incentive for shark liver oil remains. It highlights the need to proactively engage fishers and incentivize the mitigation of bycatch of deep-water sharks in Azorean waters. [ABSTRACT FROM AUTHOR]

Marine ecotourism is a pivotal sector in the blue economy strategies of many nations and is a vital economic activity for peripheral coastal regions and islands; yet a comprehensive understanding of its socioeconomic importance remains poorly quantified due to a lack of systematic evidence collation. This is even more pronounced when compared with other traditional marine activities (i.e. commercial fisheries), which are the target of monitoring programs that span several decades. The paucity of information on marine ecotourism and the disproportionate influence of traditional activities in decision-making arenas represent a practical impediment to promoting the broader agenda of blue growth and ecosystem-based management for Europe's regional seas. This study presents an assessment of the socioeconomic impact of non-extractive recreational activities closely associated with marine biodiversity (i.e. whale watching, diving and big game fishing) in one of Europe's outermost regions: the Azores archipelago (northeast Atlantic). Data were collected through a series of questionnaire surveys of the clients (n = 1740) and managers of marine-tourism businesses (n = 49). Our results suggest that in 2014 approximately 17% of total visitors to the Azores engaged in marine ecotourism activities generating approximately 80€ million in total expenditures to the regional economy (2.2% of regional Gross Domestic Product). Results also indicate that on average a typical marine ecotourist has longer stay and higher expenditure pattern compared to other visitors. These values add a new dimension to arguments in support of marine conservation and call attention to the comprehensive integration of marine ecotourism activities in management plans. [Display omitted] [ABSTRACT FROM AUTHOR]

The recognition that deep-water sharks are among the most vulnerable marine species to fisheries exploitation led to the implementation of fishing prohibition regulations in European waters. Reducing unwanted bycatch and mortality are key fisheries mitigation measure for the conservation of these species. Yet, few studies have investigated how to mitigate the common bycatch of these sharks on deep-water longline fisheries. Specifically, the potential of hook type as such a measure has never been investigated. Here, we conducted fishing experiments to test how circle hooks affect the catchability, the hooking position, and the overall condition of deep-water sharks, in comparison to the commonly used J-hooks in the Azores bottom longline fishery. We found that circle hooks did not significantly reduce deep hooking (throat or gut hooked), nor improve the overall condition of captured sharks, while the catchability of deep-water sharks on circle hooks was greater than on the J-hooks currently used in the local fishery. As such, circle hooks do not appear as a suitable measure to reduce deep-water shark bycatch and increase survival potential in deep-water longlining. Despite deep hooking being rare for the deep-water sharks caught with both hook types in the experiments, at-vessel mortality was still substantial (around 40%). Post-release survival remains mostly unquantified but preliminary results suggest it could also be high. This study highlights the urgent need for continued research addressing bycatch mitigation measures for deep-water sharks and identifying efficient strategies to reduce bycatch and increase survival. • We tested circle hook as potential bycatch mitigation measure for deep-water sharks. • Circle hooks resulted in higher catch of deep-water sharks than J-hooks. • Circle hooks did not reduce deep hooking nor improve deep-water shark condition. • Circle hooks did not appear suited to mitigate deep-water shark bycatch in longlines. • Alternative measures to reduce bycatch and improve survival are still much needed. [ABSTRACT FROM AUTHOR]

• Limited deep-sea exploration still hinders assessments of its environmental status. • We applied the Nested Environmental status Assessment Tool to deep EU waters. • 24 indicators were selected, helping implement MSFD in the EU's deep sea. • NEAT results were in reasonable agreement with expert judgement and literature. The deep sea is the largest biome on Earth but the least explored. Our knowledge of it comes from scattered sources spanning different spatial and temporal scales. Implementation of marine policies like the European Union's Marine Strategy Framework Directive (MSFD) and support for Blue Growth in the deep sea are therefore hindered by lack of data. Integrated assessments of environmental status require tools to work with different and disaggregated datasets (e.g. density of deep-sea habitat-forming species, body-size distribution of commercial fishes, intensity of bottom trawling) across spatial and temporal scales. A feasibility study was conducted as part of the four-year ATLAS project to assess the effectiveness of the open-access Nested Environmental status Assessment Tool (NEAT) to assess deep-sea environmental status. We worked at nine selected study areas in the North Atlantic focusing on five MSFD descriptors (D1-Biodiversity, D3-Commercial fish and shellfish, D4-Food webs, D6-Seafloor integrity, D10-Marine litter). The objectives of the present study were to i) explore and propose indicators that could be used in the assessment of deep-sea environmental status, ii) evaluate the performance of NEAT in the deep sea, and iii) identify challenges and opportunities for the assessment of deep-sea status. Based on data availability, data quality and expert judgement, in total 24 indicators (one for D1, one for D3, seven for D4, 13 for D6, two for D10) were used in the assessment of the nine study areas, their habitats and ecosystem components. NEAT analyses revealed differences among the study areas for their environmental status ranging from "poor" to "high". Overall, the NEAT results were in moderate to complete agreement with expert judgement, previous assessments, scientific literature on human-pressure gradients and expected management outcomes. We suggest that the assessment of deep-sea environmental status should take place at habitat and ecosystem level (rather than at species level) and at relatively large spatial scales, in comparison to shallow-water areas. Limited knowledge across space (e.g. distribution of habitat-forming species) and the scarcity of long-term data sets limit our knowledge about natural variability and human impacts in the deep sea preventing a more systematic assessment of habitat and ecosystem components in the deep sea. However, stronger cross-sectoral collaborations, the use of novel technologies and open data-sharing platforms will be critical for establishing environmental baseline indicator values in the deep sea that will contribute to the science base supporting the implementation of marine policies and stimulating Blue Growth. [ABSTRACT FROM AUTHOR]