Optimising species detection probability and sampling effort in lake fish eDNA surveys

Environmental DNA (eDNA) metabarcoding is transforming biodiversity monitoring in aquatic environments. Such an approach has been developed and deployed for monitoring lake fish communities in Great Britain, where the method has repeatedly shown a comparable or better performance than conventional approaches. Previous analyses indicated that 20 water samples per lake are sufficient to reliably estimate fish species richness, but it is unclear how reduced eDNA sampling effort affects richness, or other biodiversity estimates and metrics. As the number of samples strongly influences the cost of monitoring programmes, it is essential that sampling effort is optimised for a specific monitoring objective. The aim of this project was to explore the effect of reduced eDNA sampling effort on biodiversity metrics (namely species richness and community composition) using algorithmic and statistical resampling techniques of a data set from 101 lakes, covering a wide spectrum of lake types and ecological quality. The results showed that reliable estimation of lake fish species richness could, in fact, usually be achieved with a much lower number of samples. For example, in almost 90% of lakes, 95% of complete fish richness could be detected with only 10 water samples, regardless of lake area. Similarly, other measures of alpha and beta-diversity were not greatly affected by a reduction in sample size from 20 to 10 samples. We also found that there is no significant difference in detected species richness between shoreline and offshore sampling transects, allowing for simplified field logistics. This could potentially allow the effective sampling of a larger number of lakes within a given monitoring budget. However, rare species were more often missed with fewer samples, with potential implications for monitoring of invasive or endangered species. These results should inform the design of eDNA sampling strategies, so that these can be optimised to achieve specific monitoring goals

Lipid increases in European eel (Anguilla anguilla) in Scotland 1986–2008: an assessment of physical parameters and the influence of organic pollutants

Recruitment of the European eel (Anguilla anguilla) has fallen steadily in recent decades, with current levels understood to be at around 5 % of those in the 1970s, and the species is now widely recognised as being endangered. Changes in ocean currents, climate shifts, habitat loss, overfishing, barriers to migration, increased predation, plastic litter and exposure to chemicals have all been postulated as potential causative factors. Several studies have shown a general decline in eel quality (lower lipid content and body condition) over time that may be linked to reduced reproductive success. In this study, data from an eel sampling campaign in 1987 are compared with recent data (2004–2008) for eels in Scotland to assess any temporal changes in eel quality indicators and also to assess any links between current levels of chemical exposure and eel quality. Mean lipid levels, as a percentage of wet muscle mass, were higher in 2004–2008 (37 ± 1.9 % SE) than in 1986 (21 ± 0.9 % SE). By contrast, mean body condition index (K) was slightly lower in the latter period. Considering the 2004–2008 samples, significant inter-site variation was observed for condition index K, while intra-site variation was observed for lipid content and physical parameters relative to age (i.e. mass/age, length/age and lipid/age ratios); however, the variations observed could not be linked to differences in chemical body burdens, indicating that no chemical impacts on the parameters assessed are discernible during the continental life stage of eels in Scotland

Water Framework Directive Intercalibration Technical Report: Northern Lake Fish fauna ecological assessment methods

One of the key actions identified by the Water Framework Directive (WFD; 2000/60/EC) is to develop ecological assessment tools and carry out a European intercalibration (IC) exercise. The aim of the Intercalibration is to ensure that the values assigned by each Member State to the good ecological class boundaries are consistent with the Directive’s generic description of these boundaries and comparable to the boundaries proposed by other MS. In total, 83 lake assessment methods were submitted for the 2nd phase of the WFD intercalibration (2008-2012) and 62 intercalibrated and included in the EC Decision on Intercalibration (EC 2013). The intercalibration was carried out in the 13 Lake Geographical Intercalibration Groups according to the ecoregion and biological quality element. In this report we describe how the intercalibration exercise has been carried out in the Northern Lake Fish fauna group.JRC.H.1-Water Resource

Optimising species detection probability and sampling effort in lake fish eDNA surveys

Environmental DNA (eDNA) metabarcoding is transforming biodiversity monitoring in aquatic environments where the method has repeatedly shown comparable or better performance than conventional approaches to fish monitoring. This method has been developed and deployed, primarily using shoreline sampling during the winter months, across 101 lakes in Great Britain alone, covering a wide spectrum of lake types and ecological quality. Previous analyses on a subset of these lakes indicated that 20 water samples per lake are sufficient to reliably estimate fish species richness, but it is unclear how reduced eDNA sampling effort affects richness, or other biodiversity estimates and metrics. As the number of samples strongly influences the cost of monitoring programmes, it is essential that sampling effort is optimised for a specific monitoring objective. The aim of this project was to explore the effect of reduced eDNA sampling effort on biodiversity metrics (namely species richness and community composition) using algorithmic and statistical resampling techniques. The results showed that reliable estimation of lake fish species richness could in fact usually be achieved with a much lower number of samples. For example, in almost 90% of lakes, 95% of complete fish richness could be detected with only 10 water samples, regardless of lake area. Similarly other measures of alpha and beta-diversity were not greatly affected by a reduction in sample size from 20 to 10 samples. We also found that there is no significant difference in detected species richness between shoreline and offshore sampling transects, allowing for simplified field logistics. This could potentially allow the effective sampling of a larger number of lakes within a given monitoring budget. However, rare species were more often missed with fewer samples, with potential implications for monitoring of invasive or endangered species. These results should inform the design of eDNA sampling strategies, so that these can be optimised to achieve specific monitoring goals

Optimising species detection probability and sampling effort in lake fish eDNA surveys

Environmental DNA (eDNA) metabarcoding is transforming biodiversity monitoring in aquatic environments where the method has repeatedly shown comparable or better performance than conventional approaches to fish monitoring. This method has been developed and deployed, primarily using shoreline sampling during the winter months, across 101 lakes in Great Britain alone, covering a wide spectrum of lake types and ecological quality. Previous analyses on a subset of these lakes indicated that 20 water samples per lake are sufficient to reliably estimate fish species richness, but it is unclear how reduced eDNA sampling effort affects richness, or other biodiversity estimates and metrics. As the number of samples strongly influences the cost of monitoring programmes, it is essential that sampling effort is optimised for a specific monitoring objective. The aim of this project was to explore the effect of reduced eDNA sampling effort on biodiversity metrics (namely species richness and community composition) using algorithmic and statistical resampling techniques. The results showed that reliable estimation of lake fish species richness could in fact usually be achieved with a much lower number of samples. For example, in almost 90% of lakes, 95% of complete fish richness could be detected with only 10 water samples, regardless of lake area. Similarly other measures of alpha and beta-diversity were not greatly affected by a reduction in sample size from 20 to 10 samples. We also found that there is no significant difference in detected species richness between shoreline and offshore sampling transects, allowing for simplified field logistics. This could potentially allow the effective sampling of a larger number of lakes within a given monitoring budget. However, rare species were more often missed with fewer samples, with potential implications for monitoring of invasive or endangered species. These results should inform the design of eDNA sampling strategies, so that these can be optimised to achieve specific monitoring goals

Search for Scalar Diphoton Resonances in the Mass Range 65−60065-600 GeV with the ATLAS Detector in pppp Collision Data at s\sqrt{s} = 8 TeVTeV

A search for scalar particles decaying via narrow resonances into two photons in the mass range 65–600 GeV is performed using $20.3\text{}\text{}{\mathrm{fb}}^{-1}$ of $\sqrt{s}=8\text{}\text{}\mathrm{TeV}$ $pp$ collision data collected with the ATLAS detector at the Large Hadron Collider. The recently discovered Higgs boson is treated as a background. No significant evidence for an additional signal is observed. The results are presented as limits at the 95% confidence level on the production cross section of a scalar boson times branching ratio into two photons, in a fiducial volume where the reconstruction efficiency is approximately independent of the event topology. The upper limits set extend over a considerably wider mass range than previous searches

Finska tingsdomares bedömningar av partsutlåtanden givna på plats i rätten eller via videokonferens

Professionals within the judicial system sometimes believe they can assess whether someone is lying or not based on cues such as body language and emotional expression. Research has, however, shown that this is impossible. The Finnish Supreme Court has also given rulings in accordance with this demonstrated fact. There has also been previous research on whether party or witness statements are assessed differently in court depending on whether they are given live, via videoconference, or via prerecorded video. In the present study, we investigated how a Finnish sample of district judges (N=47) assigned probative value to different variables concerning the statement or the statement giver, such as body language and emotional expression. We also investigated the connection between the judges’ beliefs about the relevance of body language and emotional expression and their preference for live statements or statements via videoconference. The judges reported assigning equal amounts of probative value to statements given live and statements given via videoconference. However, judges found it easier to detect deception live, and this preference correlated with how relevant they thought body language is when assessing the probative value of the statement. In other words, a slight bias to assess live statements more favorably than statements given via videoconference might still exist. More effort needs to be put into making judges and Supreme Courts aware of robust scientific results that have been the subject of decades of research, such as the fact that one cannot assess whether someone is lying or not based on cues such as body language

Measurement of differential J/ψJ/\psi production cross-sections and forward-backward ratio in p+Pb collisions with the ATLAS detector

Measurements of differential cross-sections for $J/\psi$ production in p+Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV at the LHC with the ATLAS detector are presented. The data set used corresponds to an integrated luminosity of 28.1 nb$^{-1}$. The $J/\psi$ mesons are reconstructed in the dimuon decay channel over the transverse momentum range $8<p_{\mathrm{T}}<30$ GeV and over the center-of-mass rapidity range $-2.87<y^{*}<1.94$. Prompt $J/\psi$ are separated from $J/\psi$ resulting from $b$-hadron decays through an analysis of the distance between the $J/\psi$ decay vertex and the event primary vertex. The differential cross-section for production of nonprompt $J/\psi$ is compared to a FONLL calculation that does not include nuclear effects. Forward-backward production ratios are presented and compared to theoretical predictions. These results constrain the kinematic dependence of nuclear modifications of charmonium and $b$-quark production in p+Pb collisions