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In this study we solved the issue of measuring the degree of overlap/segregation among an arbitrarily large number (n ≥ 2) of 3D volumetric home ranges (i.e., x, y, and hg; where hg is height above ground level) for the first time. For this purpose, we introduced the novel non-pairwise index MVOI (Multiple Volumetric Overlap Index) and its complement to 100 MVSI (Multiple Volumetric Segregation Index). Regardless of the number of 3D volumetric home ranges, the MVOI and MVSI generate a single score of overlap/segregation between 0 and 100, making ecological interpretation much easier and more meaningful when compared to n × n pairwise overlap indices. As a case study, we applied the MVOI and MVSI to 12,081 GPS points of five lesser kestrels (Falco naumanni) during the nesting period at Santeramo in Colle (Apulia region; Italy) in an area with the most elevated density of lesser kestrels in urban colonies worldwide. The 3D volumetric home ranges ranged between 1.79 km3 and 8.19 km3. We found that the tracked birds had different vertical profiles, possibly to limit intraspecific competition, resulting in a 3D home range overlap that was only 61.1% of the 2D overlap and 52.8% of the probabilistic one.

The conservation of threatened species is prevalently oriented towards two management strategies, i.e., habitat-level and species-level approaches. The former is focused on improving the conditions of the habitat of a certain species, whereas the latter is aimed at directly strengthening the species of interest. In this work, we adopted a different solution based on a community-level approach. Firstly, we identified the species (predators, competitors, prey) that interact with the species of interest (the lesser kestrel, Falco naumanni) in Southern Italy and mapped all of the ecological interactions among these species. Secondly, we built a simulation framework of the entire ecological network of the lesser kestrel. Thirdly, we simulated different management strategies that could increase the lesser kestrel population stock by targeting the species that interact with it. We found that the lesser kestrel in Southern Italy can be effectively protected by targeting the species interacting with the lesser kestrel, and that natural changes in the abundance of the interacting species could be used to pro-actively predict the dynamics of the lesser kestrel population. Our study demonstrates that a community-level approach to species conservation is highly appropriate on a local scale. Our methodological framework, based on qualitative modeling and what-if scenarios, can be applied in the absence of quantitative estimations of population stocks and interaction strengths.

Home range overlap/segregation has several important applications to wildlife conservation and management. In this work, we first address the issue of measuring the degree of overlap/segregation among an arbitrarily large number (i.e., n ≥ 2) of probabilistic animal home ranges (i.e., utilization distributions). This subject matter has recently been solved for home ranges measured as polygons (e.g., percent minimum convex polygons and multinuclear cores) but not yet for probabilistic ones. Accordingly, we introduce a novel index named the PGOI (probabilistic general overlap index), and its complement, the PGSI (probabilistic general segregation index), an index for computation of probabilistic home range overlap/segregation at individual, population and species levels. Whatever the number of probabilistic home ranges, the PGOI returns a single score ranging in the [0, 100] interval. We applied the PGOI to five lesser kestrels (Falco naumanni) at Santeramo in Colle (Apulia region, Southern Italy) as a case study. Our new index can be applied to any animal species and to home ranges derived from any type of probabilistic home range estimator.

Capsule: Space use and flight attributes of Lesser Kestrels were revealed by global positioning system tagging at two breeding colonies in Italy. Foraging flight distances and home-range sizes were both intermediate in comparison to previous studies in higher and lower quality habitats.

Aim: Migratory animals regularly move between often distant breeding and non‐breeding ranges. Knowledge about how these ranges are linked by movements of individuals from different populations is crucial for unravelling temporal variability in population spatial structuring and for identifying environmental drivers of population dynamics acting at different spatio‐temporal scales. We performed a large‐scale individual‐based migration tracking study of an Afro‐Palaearctic migratory raptor, to determine the patterns of migratory connectivity of European breeding populations. Location: Europe, Africa. Methods: Migration data were recorded using different devices (geolocators, satellite transmitters, Global Positioning System dataloggers) from 87 individuals breeding in the three core European populations, located in the Iberian, Italian and Balkan peninsulas. We estimated connectivity by the Mantel correlation coefficient (rM), and computed both the degree of separation between the non‐breeding areas of individuals from the same population (i.e. the population spread) and the relative size of the non‐breeding range (i.e. the non‐breeding range spread). Results: European lesser kestrels migrated on a broad front across the Mediterranean Sea and Sahara Desert, with different populations using different routes. Iberian birds migrated to western Sahel (Senegal, Mauritania, western Mali), Balkan birds migrated chiefly to central‐eastern Sahel (Niger, Nigeria, Chad), whereas Italian ones spread from eastern Mali to Nigeria. Spatial differentiation of non‐breeding areas led to a strong migratory connectivity (rM = .58), associated with a relatively high population (637 km) and non‐breeding range (1,149 km) spread. Main conclusions: Our comprehensive analysis of the non‐breeding distribution of European lesser kestrel populations revealed a strong migratory connectivity, a rare occurrence in long‐distance avian migrants. The geographical conformation of the species’ breeding and non‐breeding ranges, together with broad‐front migration across ecological barriers, promoted the differentiation of migratory routes and non‐breeding areas. Strong connectivity could then arise because of both high population spread and broad non‐breeding range. CLH; FCC Energía/Enerstar Villena S.A.; Alcalá de Henares Municipality; EDF Énergies Nouvelles S.A.; EuroNatur; Fundación Iberdrola España, Grant/Award Number: Project Migra; MAVA Foundation; French Ministry of Ecology, Grant/Award Number: Lesser Kestrel National Action Plan; Greek Green Fund; European Commission, Grant/Award Number: LIFE11 NAT/IT/000068, LIFE11 NAT/BG/000360 and NAT/GR/001011; Córdoba Zoo; Seiit‐R‐4; Consejería de Agricultura, Medio Ambiente y Desarrollo Rural de Castilla‐La Mancha; MIUR, Grant/Award Number: PRIN 2010‐2011/20180‐TZKHC.

The main objective of the project “Screening methods for Water data InFormaTion in support of the implementation of the EU Water Framework Directive” (SWIFT-WFD) was to support the successful implementation of the WFD, which strongly depends on the quality and the comparability of monitoring data from river basin to river basin. In order to evaluate the performance of the laboratories using both classical and screening/emerging methods involved in the analysis of priority substances listed in the WFD, project activities included organization of three Proficiency Testing (PT) schemes at the European level for the determination of trace elements, major components, polyaromatic hydrocarbons and pesticides in water matrices, using the quality-control materials prepared within the project activities. The results of the three PT schemes were evaluated to provide a basis of information about the performance and thus the capacities of European analytical laboratories to comply with the requirements set out in the WFD.

Several proficiency tests were organized within the framework of a European project, called SWIFT-WFD, involved in implementing the Water Framework Directive (WFD). Among others, the parameters studied were polycyclic aromatic hydrocarbons (PAHs) and pesticides in organic standard solutions. The aim of this study was to evaluate the state of the art in Europe and possible sources of bias in calibration procedures. More than 30 laboratories across Europe took part in this study. These laboratories used their regular in-house analytical methods. We discuss the analytical results obtained. The averages of the results for all analytes partly agreed with the values of gravimetric sample preparation. Most of the participants in both exercises obtained satisfactory Z-scores. However significant outlier rates (in most cases around 20% of the data sets submitted) indicated that laboratories across Europe need to improve the quality of the analytical data that they deliver. We also raise some questions regarding the use of Z-scores to evaluate the laboratory performance.

Animals compete for resources, and one way to ensure access to resources is by excluding competitors from the area containing the resources. Advances in tracking technology make it possible to quantify the overlap in home ranges between individuals and between populations. We present the first evidence of space partitioning between the two main Lesser Kestrel Falco naumanni colonies with the highest numbers of individuals in Italy, and with the highest densities of Lesser Kestrels in inhabited areas in their Eurasian breeding range. Using GPS data loggers, we collected 41,126 GPS points of Lesser Kestrels from both colonies during the nestling period. Home range overlap between the two colonies was almost zero at both 100%- and 99%-isopleths, and zero at 95%- and 90%-isopleths. Using a randomization procedure, we could show that home ranges were more spatially-segregated than expected by chance. We did detect increased overlap in home ranges among individuals within colonies. Although our results require further confirmation, they suggest that competition for food between colonies is weaker due to this strategy of spatial segregation of foraging areas. Our study confirms the recent notion that between-colony areal segregation may be the norm in colonial central-place foragers.

Several analytical methods have been developed in the last 20 years for the determination of organotin compounds in mussel tissue. These methods encompass a huge variety of different extraction methods of poorly known efficiency. The quantitative evaluation of the extraction efficiency of these methods has been hindered by the lack of mussel reference materials and the presence of other potential sources of errors such as derivatisation and purification steps. The extraction efficiencies of 12 selected methods for the analysis of butyl- and phenyltin compounds in mussel samples have been compared. The comparison was carried out by analysing a mussel tissue reference material (CRM 477) with certified and indicative values for butyltins and phenyltins, respectively, recently made available by the European Commission's Standards, Measurements and Testing Programme. Derivatisation, clean-up and analysis were rigorously the same in all the methods considered. The high homogeneity of the samples and the identical experimental conditions allowed comparison of the extraction efficiencies.