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We investigated the effect of temperature on the limiting oxygen saturation (LOS) of gilthead sea bream Sparus aurata. This threshold was defined as the % O2 saturation where fish no longer upheld their routine metabolic rate (RMR, the metabolic rate of fed and active fish) during a progressive decline in oxygen saturation. S. aurata (398 ± 10 g, mean ± SE) were kept in 3 replicate tanks and subjected to 3 changes in temperature: 16 to 20°C, 20 to 16°C and 16 to 12°C. At each temperature, fish were left to acclimatize for 8 to 10 d, before daily feed intake (DFI), the routine oxygen consumption rate (routine MO2, mg kg-1 min-1) and the LOS were measured. In addition, at 20°C the swimming speed was measured in fish subjected to a decline in O2 from full air saturation to levels below the LOS (minimum of 8-10% O2). For the temperature range tested (12-20°C), DFI, MO2 and LOS increased exponentially with temperature (7.5-, 3.6- and 2.2-fold, respectively) with mean (± SE) LOS being 17 ± 1, 21 ± 0 and 35 ± 5% O2 at 12, 16 and 20°C, respectively. A gradual decline in swimming activity was observed as O2 declined below the LOS, indicating increasing metabolic stress and/or a 'sit-out' coping strategy which may prolong survival time in severe hypoxia. The results show the importance of temperature as an influential variable over the environmental O2 requirements of S. aurata. © The authors 2015. The study was funded by the EU Seventh Framework Programme by the AQUAEXCEL (FP7-2007-2012; grant agreement no. 262336) and the Norwegian Research Council through the Centre for Research-based Innovation in Aquaculture Technology, CREATE. Peer Reviewed

[Main conclusion] Both AE and SIE rarity on La Palma show a clear spatial pattern, with hotspots of endemic rarity found at high elevations and in rare climates, presumably owing to geographical and climatic constraints and possibly anthropogenic pressure (e.g., land use, introduced herbivores, fire). Areas of high rarity estimates coincide with the distribution and extent of PAs on La Palma, especially since the recent addition of the Natura 2000 sites. The hypervolume approach is a promising tool to estimate species range sizes, and can be applied on all scales where point/plot data are available. [Methods] We recorded all present endemic vascular plant species in 1,212 plots covering the entire island. We calculated endemic rarity (corrected range-rarity richness for endemics) using a rarity estimation approach based on kernel density estimations (hypervolume approach). We performed a sensitivity analysis based on multiple linear regressions and relative importance estimations of environmental drivers to estimate the performance of the hypervolume-based rarity estimation compared to standard methods (occurrence frequency, convex hulls, alpha hulls). [Aim] Rarity—an important measure for conservation biogeography—can vary over many orders of magnitude. However, it is unclear which regional-scale abiotic conditions drive processes affecting rarity of endemic species on islands. To support conservation efforts, we (1) assess the main abiotic drivers of endemic rarity, (2) determine how well existing protected areas (PAs) coincide with hotspots of endemic rarity and (3) introduce and evaluate a new hypervolume-based rarity estimator. [Results] Climate variables (mean annual temperature, climatic rarity, precipitation variability) best explained archipelago endemic (AE) and single-island endemic (SIE) rarity. Existing PAs covered the majority of AE and SIE rarity, especially national and natural parks as well as the Natura 2000 sites. In our study system, hypervolumes performed better than standard measures of range size. This work contributed to and was partially supported by the European H2020 Project 641762 ECOPOTENTIAL: Improving future ecosystem benefits through Earth Observations. [Location] La Palma (Canary Islands). © 2017 The Authors. Peer Reviewed

Provide an overview of legal challenges that need to be considered when developingstrategies and suggest good practise recommendations of how these challenges can be addressed.

The purpose of this document is to establish a framework for the analysis of Multi-Use (MU) in the sea basin context, which will provide the project consortium with the practical research tools necessary to examine theoretical understanding and practical experience related to MU. This framework will guide further analyses and also feed into Work Package (WP) 3 - Case Study Analysis. For this specific purpose, this analytical framework (AF) will be considered in the preparation of the Case Study Methodology (D3.1), aiming at maximizing the degree of commonality between the two scales of analysis (Sea Basin scale and local scale). The analytical framework is intended to guide the process of information and data gathering and stakeholder engagement, providing the needed degree of homogeneity to the analysis of different Sea Basins. The framework should be interpreted as a flexible tool, and it may be modified and adapted through the implementation process, according to the emerging needs. In the event of changes or additions to the framework described herein being encountered, a technical note will be prepared by the WP2 leader, describing the amendments to the methodology. After WP2 completion, a revised version of this framework will be prepared, incorporating all changes.

Enteromyxum leei is a myxozoan histozoic parasite that infects the intestine of several teleost fish species. In gilthead sea bream (Sparus aurata), it provokes a chronic disease, entailing anorexia, delayed growth, reduced marketability and mortality. Direct fish‐to‐fish transmission, relevant in aquaculture conditions, has been demonstrated for E. leei via effluent, cohabitation, and oral and anal routes. However, the minimum time of exposure for infection has not been established, nor the possible effect on the fish immune response. Two effluent trials were performed at different temperatures (high: average of 25.6°C; and low: constant at 18°C), different times of exposure to the effluent (1, 3, 5 and 7 weeks) and different population densities. The results showed that 1 week was enough to infect 100% of fish at high temperature and 58.3% at low temperature. High temperature not only increased the prevalence of infection in posterior intestine, but also induced a higher production of specific antibodies, limiting the progression of the infection along the intestine. Longer time of exposure to the parasite and higher fish densities facilitated E. leei infection. These results show that effective diagnosis, lowering animal density and removal of infected fish are key aspects to manage this disease in aquaculture facilities. This work has been carried out with financial support from the European Commission, Horizon 2020 Framework Programme H2020, Societal Challenges under grant agreement 634429 (ParaFishControl). This publication reflects only the authors' view, and the European Union cannot be held responsible for any use that may be made of the information contained therein. IE was contracted under APOSTD/2016/037 grant by the “Generalitat Valenciana,” and MCP, under Consejo Superior de Investigaciones Científicas CSIC PIE project no. 201740E013. Peer reviewed

Macrophages play important roles in conditions ranging from host immune defense to tissue regeneration and polarize their functional phenotype accordingly. Next to differences in the use of L-arginine and the production of different cytokines, inflammatory M1 macrophages and anti-inflammatory M2 macrophages are also metabolically distinct. In mammals, M1 macrophages show metabolic reprogramming toward glycolysis, while M2 macrophages rely on oxidative phosphorylation to generate energy. The presence of polarized functional immune phenotypes conserved from mammals to fish led us to hypothesize that a similar metabolic reprogramming in polarized macrophages exists in carp. We studied mitochondrial function of M1 and M2 carp macrophages under basal and stressed conditions to determine oxidative capacity by real-time measurements of oxygen consumption and glycolytic capacity by measuring lactate-based acidification. In M1 macrophages, we found increased nitric oxide production and irg1 expression in addition to altered oxidative phosphorylation and glycolysis. In M2 macrophages, we found increased arginase activity, and both oxidative phosphorylation and glycolysis were similar to control macrophages. These results indicate that M1 and M2 carp macrophages show distinct metabolic signatures and indicate that metabolic reprogramming may occur in carp M1 macrophages. This immunometabolic reprogramming likely supports the inflammatory phenotype of polarized macrophages in teleost fish such as carp, similar to what has been shown in mammals.

Report on operational procedures for evaluation of policy and structuring actions

Sediments in the Nazare Canyon (NE Atlantic) are inhabited by unexpectedly high abundances of the deposit-feeding holothurian Molpadia musculus. The energetic demand of such a large megafaunal biomass is presumably high and requires the efficient exploitation of the food inputs coming from the photic zone. We hypothesise the existence of cooperative interactions between these deep-sea holothurians and prokaryotes in their guts. To investigate these interactions, sediment samples and holothurians were collected at ca. 3500 m depth using a Remote Operated Vehicle (ROV) and an incubation chamber used to "harvest" faeces from the holothurian. In all of these samples (ingested sediment from different sectors of the holothurian gut content, faeces and sediments) we determined total prokaryotic abundance, the relative abundance of Bacteria and Archaea (by means of Catalysed Reporter Deposition-Fluorescence in situ Hybridisation) and bacterial diversity (by means of fingerprinting techniques: ARISA and T-RFLP). Prokaryotic abundances and bacterial diversity in the holothurian gut were very high (up to 10(5) bacterial Operational Taxonomic Units) and significantly greater than in surrounding bottom sediments. Archaea represented a key component within the gut of the holothurians and in certain tracts dominated the prokaryotic assemblage. We also found that ca. 40% of bacterial OTUs were associated uniquely with the gut contents (i.e., absent in surrounding sediments). These findings suggest the occurrence of wide and highly diversified interactions between prokaryotes and deep-sea holothurians. Results presented here provide new insights into the potential relationships between deep-sea holothurians and specific associations of Archaea and Bacteria within their guts. The work opens new perspectives for investigating the diversity of prokaryotes associated to deep-sea megafauna. (C) 2012 Elsevier Ltd. All rights reserved.

A manuscript to be submitted as scientific publication reviewing the study fisheries in terms of unwanted catches

Galicia (NW Spain) is an important fishing region with a high potential for cetacean–fishery interactions. Cetacean depredation on catch and damage to fishing gear can potentially lead to substantial economic loss for fishers, while cetacean bycatch raises conservation concerns. With the aim of gathering information on the types and scale of interactions and of suggesting possible management strategies, we conducted face-to-face interviews with fishers in local fishing harbours, in particular to identify specific problematic interactions and to quantify the level of economic loss and bycatch rates associated with these interactions. We found that cetacean–fishery interactions are frequent, although damage to catch and fishing gear by cetaceans was mostly reported as small. Nevertheless, substantial economic loss can result from common bottlenose dolphins (Tursiops truncatus) damaging coastal gillnets and from short-beaked common dolphins (Delphinus delphis) scattering fish in purse-seine fisheries. Cetacean bycatch mortality was reported to be highest for trawls and set gillnets, and probably exceeds sustainable levels for local common and bottlenose dolphin populations. Although interview data may be biased due to the perceptions of interviewees, and therefore should be interpreted with care, the methodology allowed us to cover multiple sites and fisheries within a reasonable time frame. Minimizing cetacean–fishery interactions requires the implementation of case-specific management strategies with the active participation of fishers. For set gillnet and purse-seine fisheries, the use of acoustic deterrent devices (pingers) may prevent cetaceans from approaching and getting trapped in the nets. For trawl fisheries, where bycatch appears to be particularly high at night in water depths of 100–300 m, possible solutions include the implementation of time/area closures and the relocation of some fishing effort to deeper waters The study was funded by the EC projects MEXC-CT-2006-042337 and MEST-CT-2005-020501), the German Academic Exchange Service (DAAD), and the Fundação para a Ciência e a Tecnologia (FCT). MBS participation was part of the EU FP7 grant MYFISH (No. 289257) and the LOTOFPEL project (Plan Nacional de I + D + I, CTM 2010-16053) 14 pages, 5 figures, 3 tables Peer reviewed