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Contains fulltext : 191643.pdf (publisher's version ) (Open Access)

Some bottlenose dolphins use marine sponges as foraging tools (‘sponging'), which appears to be socially transmitted from mothers mainly to their female offspring. Yet, explanations alternative to social transmission have been proposed. Firstly, the propensity to engage in sponging might be due to differences in diving ability caused by variation of mitochondrial genes coding for proteins of the respiratory chain. Secondly, the cultural technique of sponging may have selected for changes in these same genes (or other autosomal ones) among its possessors. We tested whether sponging can be predicted by mitochondrial coding genes and whether these genes are under selection. In 29 spongers and 54 non-spongers from two study sites, the non-coding haplotype at the HVRI locus was a significant predictor of sponging, whereas the coding mitochondrial genes were not. There was no evidence of selection in the investigated genes. Our study shows that mitochondrial gene variation is unlikely to be a viable alternative to cultural transmission as a primary driver of tool use in dolphins

Background: The European directive on basic safety standards (Council directive 2013/ 59 Euratom) mandates dosimetry-based treatment planning for radiopharmaceutical therapies. The directive comes into operation February 2018, and the aim of a report produced by the Internal Dosimetry Task Force of the European Association of Nuclear Medicine is to address this aspect of the directive. A summary of the report is presented. Results: A brief review of five of the most common therapy procedures is included in the current text, focused on the potential to perform patient-specific dosimetry. In the full report, 11 different therapeutic procedures are included, allowing additional considerations of effectiveness, references to specific literature on quantitative imaging and dosimetry, and existing evidence for absorbed dose-effect correlations for each treatment. Individualized treatment planning with tracer diagnostics and verification of the absorbed doses delivered following therapy is found to be scientifically feasible for almost all procedures investigated, using quantitative imaging and/or external monitoring. Translation of this directive into clinical practice will have significant implications for resource requirements. Conclusions: Molecular radiotherapy is undergoing a significant expansion, and the groundwork for dosimetry-based treatment planning is already in place. The mandated individualization is likely to improve the effectiveness of the treatments, although must be adequately resourced.

Fish farms have been shown to aggregate large numbers of wild fish in their surroundings. Although little is known about how this affects the local fishery, two hypotheses have been put forward; a trapping and a protecting effect on wild fish. This study provides the first monitoring of commercial and recreational fishing activity at a fish farm. We assessed the effect on the small-scale fishery analysing the differences between fishing in farm proximity and away from the farm (in terms of catch rate, income and catch composition). Moreover, we estimated the biomass removal from fishing activities by farm employees inside the farm. The study was conducted from January 2011 to June 2012 at a Gilthead seabream farm in the NW Mediterranean. The findings revealed a relevant amount of commercial and recreational fishing effort in farm proximity. Yet, the results showed no benefit or difference of fishing in close proximity to the farm compared with areas away from the farm. Thus, we conclude that farm-aggregated fish are protected from the commercial fleet by the farm leasehold area, but remain vulnerable to hidden fishing practices inside the farm, where farm employees harvest more than 4 t of wild fish annually.

Individual foraging tactics are widespread in animals and have ecological and evolutionary implications. Indo-Pacific bottlenose dolphins (Tursiops sp.) in Shark Bay, Western Australia, exhibit a foraging tactic involving tool use, called "sponging." Sponging is vertically, socially transmitted through the matriline and, to date, has been described in detail in the eastern gulf of Shark Bay (ESB). Here, we characterize sponging in the western gulf of Shark Bay (WSB), in which a different matriline engages in the behavior. We identified 40 individual "spongers" in 9 mo of boat-based surveys over three field seasons. As is the case in ESB, the majority of WSB spongers was female and engaged in sponging in deep channel habitats. In contrast to ESB, however, there was no difference in the number of associates between spongers and nonspongers in WSB, and activity budgets differed between spongers and deep-water nonspongers; spongers foraged more frequently and rested less than nonspongers. Group sizes in deep channel habitat, where sponging was prevalent, were typically larger than those in shallow habitat, except for foraging, perhaps indicative of higher predator abundance and/or scattered prey distribution in deep-water habitat. This research improves our understanding of within-population foraging variations in bottlenose dolphins.

Marine aquaculture production is becoming increasingly important to meet global seafood demands. Conversely, there are concerns about potential environmental impacts, especially associated with marine fish farming, and the access to and use of coastal resources. While only a small number of studies on social acceptability of fish farming exist, understanding the range of perceptions among social groups is a key challenge for successful management of aquaculture, and thus for sustainable development. The case study presented here uses the Qmethodology to explore the perceptions of five aquaculture-related key stakeholder groups (NGOs, local fishermen, fish farming industry, scientists and regional administration) towards marine fish aquaculture in Catalonia (NE Spain). The 30 participants were asked to sort 39 statements about environmental, social and economic aspects of marine fish farming, on a scale from strongly agree to strongly disagree. The factor analysis identified four distinct factors, each representing a different perception. While Perception 1 regards fish farming as an activity with important socio-economic benefits and low environmental costs, Perception 2 gives highest importance to environmental concerns. Perception 3 represents a more balanced view, valuing the socio-economic benefits and expressing moderate concern about environmental impacts, whereas Perception 4 focuses mainly on economic aspects. Interestingly, the four perceptions were represented by various groups of stakeholders and not all respondents from the same sector shared the same perception. This study contributes to the scarce scientific information on social research on aquaculture, revealing limitations, challenges, and opportunities of the industry.

Marine debris such as plastic and other foreign objects (e.g., nylon fishing line, cigarette wrappers, metal bottle caps) are commonly found in odontocete stomachs (Walker and Coe 1990), but due to the often small amounts and diversity of the debris, the impact on animal health is unclear (Walker and Coe 1990, Laist 1997, Baird and Hooker 2000). Small quantities can however, have large effects if they are capable of intermittently or consistently blocking the pyloric outflow tract (e.g., Tarpley and Marwitz 1993, Stamper et al. 2006, Jacobsen et al. 2010) causing longterm malnutrition and death (Gomerˇci´c et al. 2006); either directly due to acute gastric rupture or complete pyloric obstruction, or indirectly as a result of chronic malnutrition due to partial/intermittent pyloric obstruction. Kastelein and Lavaleije (1992) documented the persistence of undigested algae in the forestomach of a harbor porpoise for at least 3 d. Several other odontocete species (e.g., bottlenose dolphins (Tursiops truncatus, e.g., McBride 1940), northern right whale dolphins (Lissodelphus borealis,Walker and Coe 1990), and spinner dolphins (Stenella longirostris, Trianni and Kessler 2002)) have been found to ingest marine plants, such as kelp (Egregia sp., Macrocystic pyrifera), seaweed (Fucus vesiculosus) or seagrass (Enhalus acroides, Haldule uninervis). However, death due to gastric impaction by marine plants (high densities of intertwined marine plant(s) preventing efficacious pyloric emptying and gastric evacuation (Santos et al. 2001)) is rarely reported (see McBride 1940, Trianni and Kessler 2002).

This study investigates the predation of P. noctiluca ephyrae on Atlantic Bluefin tuna (ABFT) eggs under different experimental conditions. The specific factors considered in the experimental design were: a) water mix conditions to explore predation under two-dimensional (2D) and three-dimensional (3D) prey distributions, b) prey density to investigate the ingestion rate capacity, and c) incubation time to inspect gut saturation. The eggs and jellyfish ephyrae were collected during the 2012 ABFT spawning survey off Ibiza (Balearic Isl., Western Mediterranean). The results showed that the proportion of feeding ephyrae increased with size. The mean clearance rate of feeding ephyrae, 4.14 L h-1, was the highest ever recorded for ephyrae. Under calm conditions the eggs floated at the surface (2D spatial arrangement) and the clearance rates, at low prey densities, were at least twice those under mixed conditions (3D spatial arrangement). At high prey density, clearance rate did not differ between mix conditions, probably due to the fast gut saturation, which was reached in c.a. 15 min, as revealed by time series observations of gut contents. The fast saturation of ephyrae and their slow digestion time of approximately 18 h suggest the existence of a diel feeding periodicity. We conclude that in the Western Mediterranean, P. noctiluca ephyrae are capable of predating on ABFT eggs, a highly pulsed and spatially restricted resource that potentially switches from a 3D to a 2D configuration in the absence of wind-generated turbulence. The P. noctiluca and Atlantic Bluefin tuna egg system might represent an example of a general mechanism linking pelagic and neustonic food webs.

Factors influencing within-farm variability of wild fish aggregations have not been systematically studied. We tested the hypothesis that fish abundance and species composition vary between feeding and non-feeding periods and different bottom substrates within a Sparus aurata (L.) farm. Sampling took place during feeding and non-feeding periods on six consecutive days in July 2011. Visual censuses were carried out at three different depths and at three sampling stations over rocky– sandy and sandy substrates respectively. In all, 33 species belonging to 17 families were observed. Total fish abundance, biomass and species community significantly differed between feeding and non-feeding periods. Each depth was represented by a distinct species community and was therefore affected differently by the feeding activity. At the surface, fish abundance was significantly higher during feeding compared with non-feeding periods. The distance from the feeding vessel significantly influenced fish aggregations in the water column, indicating that planktivorous species learnt to associate the boat noise with food availability through classic conditioning. At the bottom, substrate type was the dominant factor explaining aggregation variability. This study provides new information about the dynamics of fish aggregations within farms, emphasizing the importance of considering the different sources of variability in future study designs.

Fish farms cause wild fish to aggregate nearby and thus act to modify their distribution, but the spatial and temporal extent of the attraction effect around farms is still poorly understood. We examined attraction using an integrated approach combining 3 factors: spatial extent, depth and season. We analysed an Atlantic bluefin tuna Thunnus thynnus (ABT) and a gilthead seabream Sparus aurata (SB) farm off the north-eastern coast of Spain which represent different fish farming models in the Mediterranean. Underwater visual counts were conducted from summer 2010 to spring 2011. We recorded 39 species at the SB farm and 17 species at the ABT farm. The analysis of fish abundance and biomass at 3 stations located along a distance gradient from the farm (SB: 0, 30, 200 m; ABT: 0, 100, 200 m) showed significantly higher values next to the cages than at more distant stations, revealing that the spatial extent of the attraction effect was mainly restricted to the cage rather than following a gradient. The intensity of the cage effect varied according to farm, season and depth, reflecting species-specific behaviours. At the SB farm, the cage effect persisted year round, varying with depth, whereas at the ABT farm, the effect was only detected in summer and spring. These distinct spatial and temporal aggregation patterns suggest that implementation of fishery regulatory measures to protect wild fish should be farm-specific. This study emphasizes the importance of using an integrated approach to study wild fish aggregations at farms.

For 318 patients in 8 different Belgian hospitals, the entire skin-dose distribution was mapped using a grid of 70 thermoluminescence dosemeters per patient, allowing an accurate determination of the maximum skin dose (MSD). Dose-area product (DAP) values, exposure parameters and geometry, together with procedure, patient and cardiologist characteristics, were also registered. Procedures were divided into two groups: diagnostic procedures (coronary angiography) and therapeutic procedures (dilatation, stent, combined procedures (e.g. coronary angiography + dilatation + stent)). The mean value of the MSD was 0.310 Gy for diagnostic and 0.699 Gy for therapeutic procedures. The most critical projection for receiving the MSD is the LAO90 (left anterior oblique) geometry. In 3% of cases, the MSD exceeded the 2 Gy dose threshold for deterministic effects. Action levels in terms of DAP values as the basis for a strategy for follow-up of patients for deterministic radiation skin effects were derived from measured MSD and cumulative DAP values. Two DAP action levels are proposed. A first DAP action level of 125 Gy cm(2) corresponding to the dose threshold of 2 Gy would imply an optional radiopathological follow-up depending on the cardiologist's decision. A second DAP action level of 250 Gy cm(2) corresponding to the 3 Gy skin dose would imply a systematic follow-up. Dose reference levels - 71.3 Gy cm(2) for diagnostic and 106.0 Gy cm(2) for therapeutic procedures - were derived from the 75 percentile of the DAP distributions. As a conclusion, we propose that total DAP is registered in patient's record file, as it can serve to improve the follow-up of. patients for radiation-induced skin injuries.