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The study of insular populations was key in the development of evolutionary theory. The successful colonisation of an island depends on the geographic context, and specific characteristics of the organism and the island, but also on stochastic processes. As a result, apparently identical islands may harbour populations with contrasting histories. Here, we use whole genome sequences of 65 barn owls to investigate the patterns of inbreeding and genetic diversity of insular populations in the eastern Mediterranean Sea. We focus on Crete and Cyprus, islands with similar size, climate and distance to mainland, that provide natural replicates for a comparative analysis of the impacts of microevolutionary processes on isolated populations. We show that barn owl populations from each island have a separate origin, Crete being genetically more similar to other Greek islands and mainland Greece, and Cyprus more similar to the Levant. Further, our data show that their respective demographic histories following colonisation were also distinct. On the one hand, Crete harbours a small population and maintains very low levels of gene flow with neighbouring populations. This has resulted in low genetic diversity, strong genetic drift, increased relatedness in the population and remote inbreeding. Cyprus, on the other hand, appears to maintain enough gene flow with the mainland to avoid such an outcome. Our study provides a comparative population genomic analysis of the effects of neutral processes on a classical island-mainland model system. It provides empirical evidence for the role of stochastic processes in determining the fate of diverging isolated populations.

The combined actions of climatic variations and landscape barriers shape the history of natural populations. When organisms follow their shifting niches, obstacles in the landscape can lead to the splitting of populations, on which evolution will then act independently. When two such populations are reunited, secondary contact occurs in a broad range of admixture patterns, from narrow hybrid zones to the complete dissolution of lineages. A previous study suggested that barn owls colonized the Western Palearctic after the last glaciation in a ring-like fashion around the Mediterranean Sea, and conjectured an admixture zone in the Balkans. Here, we take advantage of whole-genome sequences of 94 individuals across the Western Palearctic to reveal the complex history of the species in the region using observational and modeling approaches. Even though our results confirm that two distinct lineages colonized the region, one in Europe and one in the Levant, they suggest that it predates the last glaciation and identify a secondary contact zone between the two in Anatolia. We also show that barn owls recolonized Europe after the glaciation from two distinct glacial refugia: a previously identified western one in Iberia and a new eastern one in Italy. Both glacial lineages now communicate via eastern Europe, in a wide and permeable contact zone. This complex history of populations enlightens the taxonomy of Tyto alba in the region, highlights the key role played by mountain ranges and large water bodies as barriers and illustrates the power of population genomics in uncovering intricate demographic patterns.

We evaluated how fire impacts the ecological coherence of Aleppo pine forests and their biodiversity over a 40-year period. The study area forms part of an insular ecosystem of Zakynthos Island (Zante) in western Greece, which forms part of the Ionian Islands. Post-fire effects were studied for both plant and bird diversity at 20 sampling plots, using stratified random sampling, during the summer of 2012. The plots were selected based on the frequency of burning since the 1970s. Sites were categorized as: 1) no burning for >40 years, 2) burnt once in the 1970s, 3) burnt twice, first in the 1970s and again in 2000–2010, 4) burnt three times, first in the 1970s, and twice more in 2000–2010, and 5) burnt four times, first in the1970s, twice more in 2000–2010, and again in 2011. A total of 79 plant species and 26 bird species were recorded at the studied sites. One-way ANOVA analysis showed that fire intensity has a significant impact on alpha floristic diversity. Average plant species richness at sites that burned in 2011 was significantly higher than in those that burned in the 1970s. Detected differences in bird species richness were not significant; however, more species were documented in the forested habitats (unburnt for >40 years, and burnt in the 1970s). The highest Jaccard similarity index was observed between the sites that had not burned for more than 40 years and the sites that burned in the 1970s. The lowest floristic similarity to non-burnt sites was observed between the recently burnt sites in 2011 and the sites that burned in the 1970s. The lowest bird similarity was detected between recently burnt sites in 2011 and sites that had not burned for more than 40 years. DCA ordination showed the presence of a clear fire gradient, from intensively burnt open sites to non-burnt forest sites. We suggest that fire is essential to maintain biodiversity in Aleppo pine forests, but only at intermediate frequency.

The Common Agricultural Policy (CAP) of the European Union (EU) is one of the world's largest agricultural policies and the EU's longest-prevailing one. Originally focused mostly on supporting production and farm income, the CAP has progressively integrated instruments to support the environment. Nonetheless, there is considerable agreement among EU citizens that the CAP still does not do enough to address ongoing environmental degradation and climate change (92% of nonfarmers, 64% of farmers) (1). In May and June 2018, the European Commission (EC) published the financial plan and legislative proposal for the CAP post-2020 (2), prompting numerous proposed amendments that the newly elected European Parliament (EP) will now have to consider. With an eye toward the next and final reform stages, including budget discussions and “trilogue” negotiations between the EC, the Council, and the EP to begin in autumn 2019, we examine whether the proposed post-2020 CAP can address key sustainability issues and meet societal demands for higher environmental performance.

Home range size and foraging habitat use in breeding lesser kestrels (Falco naumanni), a bird species of conservation concern, were investigated during the breeding season of the species in 2008 in an intensively cultivated area of central Greece, using radio-tracking. Grasshopper (the main prey) densities were measured at the most important habitats (cotton, cereals, grasslands and margins). Home ranges were not significantly different between sexes either as overall means or during incubation and nestling periods. Movements of both sexes were non-random during incubation but random during the nestling period. Habitats used by males during incubation ranked as: margins > other > cotton > corn > cereals and during nestling period as: cereals > margins > grasslands > corn > cotton. Female habitat use greatly differed ranking as cereals > cotton > grasslands during incubation and as grassland > cotton > corn > cereals > margins during nestling period. Female habitat use seemed to be in disagreement with the...

Densidad de poblacion y tendencias de la perdiz griega oriental (Alectoris graeca graeca) en Grecia central La perdiz griega es una especie emblematica de la avifauna griega y una de las especies cinegeticas mas importantes del pais. En este estudio, en el que combinamos recuentos in situ a largo plazo con la metodologia de muestreo a distancia, en Grecia central, indico que la poblacion de dicha especie en Grecia es la mayor de toda la zona de distribucion europea, contrastando con todos los estudios anteriores. Las tendencias interanuales sugirieron la existencia de una poblacion de perdiz griega estable tanto en los cotos de caza como en los refugios de fauna, mientras que en verano, esta especie presentaba densidades significativamente mas altas a altitudes de mas de 1.000 m, probablemente debido a los efectos de la depredacion en las zonas inferiores. La similitud de la estructura de la poblacion entre los refugios de fauna y las zonas de caza, junto a las tendencias poblacionales estables, demostraron que la caza de la perdiz griega en el pais es sostenible.

We analysed diet data in a Long-legged Buzzard Buteo rufinus population using four different methods (direct observations, pellets, prey remains and combined pellets and prey remains) from Cyprus, during 2005–2007. Direct observations can provide reliable diet information. However, the small sample size of monitored nests, the subjective selection of accessible nests, the differential prey size deliveries by different sexes, and the different recognition of different prey species could involve biases, therefore accounting for the low dietary breadth. Prey remains differed significantly from pellet analysis due to more birds and fewer lizards, but the broadest trophic spectrum was obtained. Pellets analysis failed to detect small-sized prey items, but provided a high number of species present in the diet. Pellets and pooled data corresponded closely with the results of direct observations. Pooling data from pellets and prey remains overcame the problems associated with these two methods and revealed a high diet diversity and a great similarity to direct observations. Our results suggest that the pooled data method will be effective for monitoring dietary trends in the breeding and non-breeding Long-legged Buzzard population.

Stone martens (Martes foina) are documented as generalist throughout their distributional range whose diet composition is affected by food availability. We tested if this occurs and what feeding strategies it follows in a typical Mediterranean ecosystem in Central Greece by analysing contents from 106 stomachs, seasonally collected from three different habitats during 2003–2006. Seasonal variation in diet and feeding strategies was evident and linked to seasonal nutritional requirements, but possibly imposed by strong interference competition and intraguild predation. Fleshy fruits and arthropods predominated in the diet, but also mammals and birds were frequently consumed. An overall low dietary niche breadth (BA=0.128) indicated a fruit specialization tendency. A generalised diet occurred in spring with high individual specialisation, whereas more animal-type prey was consumed than fruits. A population specialization towards fruits was indicated during summer and autumn, whereas insects were consumed occasionally by males. In those seasons it switched to more clumped food types such as fruits and insects. In winter it selectively exploited both adult and larvae insects and partially fruits overwinter on plants. The tendency to consume particular prey items seasonally reflected both the population specialist behaviour and the individual flexibility preyed on different food resources.

Capercaillie is a species of particular conservation importance for Europe due to the observed population decline in various parts of its distribution. In the current study, the environmental and habitat requirements of the species are investigated at the southernmost range of its European distribution (Rodopi Mountain-Range National Park, northern Greece) using a set of 95 observations of species presence and a maximum-entropy (MaxEnt) modeling approach. A bioclimatic dataset derived from the Bioclim open source database and a set of environmental variables, mainly forest land-cover types and topographical variables, were employed to explain the current distribution of the species and to delineate potentially suitable areas for its distribution. The best scale per environmental variable was chosen among three different spatial scales (10 ha, 100 ha and 500 ha), in order to build a multiscale environmental model. According to our results, the species demonstrated a very narrow niche which is determined primarily by bioclimatic factors while a number of habitat requirements within a strict bioclimatic zone where also identified. It requires wet areas with mean summer temperature not exceeding 10 °C, which are only found at the higher altitudes of the National Park. Α strong tendency was also found for capercaillies to inhabit forest stands of norway spruce (Picea abies) with a minimum cover of 10% at an intermediate scale of 100 ha, followed at a larger scale i.e. 500 ha by pure beech (Fagus spp.) forests or mixed with pines (Pinus spp.), where optimum tree density ranges from 50% to 80%. Bioclimatic and environmental presence-prediction maps were reclassified in four suitability classes (unsuitable, marginal, sub-optimal, optimal), based on three Maxent thresholds (Minimum Training Presence, Fixed Cumulative Value 5 and Value 10). Monitoring the marginal climatic zone for the species and ensuring suitable habitats within it is the key for the species conservation in its southernmost part of its distribution. Keywords: Capercaillie, Rodopi Mountain-Range National Park, Habitat suitability, Optimal niche, MaxEnt

Climate forcing, which is blamed for the decennial decline in the dynamics of vole populations in Central and Northern Europe, may have similar effects in southern (Mediterranean) Europe, even more so since the region is especially vulnerable to global change. In the absence of population monitoring, we investigated the temporal development and geospatial pattern of the habitat of Harting’s vole (Microtus hartingi) in southeast Europe (SEE) by relying on data regarding its presence, the most recent freely available geospatial datasets and state-of-the-art presence-only Species Distribution Modelling (SDM) techniques. Results indicate that (1) the potential habitat of Harting’s vole was perhaps stable over the last 6000 years - modelling predictions are in conjunction with scarce fossil evidence, which points to repeated colonisations from Asia Minor punctuated by extinctions in SEE; (2) fragmentation of the potential habitat in SEE, which may have already begun in the Last Glacial Maximum, and will most likely continue in the near future; and (3) Harting’s vole could disappear by the end of the century if more pessimistic climate change scenarios become reality. While climate change is suppressing the population dynamics of the keystone grass-eating voles from temperate and boreal ecosystems, it is about to annihilate their Mediterranean counterpart. This will result in a far more severe impact on community restructuring in the Mediterranean ecosystems than elsewhere. Long-term population monitoring is desperately needed in SEE to hone the ability to more accurately predict the impacts of climate change.

Diet composition of the Barn Owl Tyto alba was studied in agricultural landscapes in Thessaly, Greece, for 3 years (2003–05). A total of 852 Rattus spp. individuals were identified from 10 065 pellets, which accounted for 2.9% by frequency and 27.4% by biomass of 29 061 prey items. Rattus spp. were more numerous in Barn Owl pellets during winter months than in summer. We suggest that this difference was due to a shift in relative prey availability and an increased need for energy by the Barn Owl during the colder months. Comparisons between Thessaly and 15 other areas showed differences in prey availability between islands and mainland Greece. Microtus spp. were absent from all island diets except one, and some islands had greater species richness.

Forested areas provide important breeding habitats for the turtledove (Streptopelia turtur) in Dadia-Lefkimi-Soufli National Park, Northeastern Greece. We censused the birds in two forested habitat types using the point-count technique at 60 sites during the breeding season (from mid-April to mid-June) in 2001 and 2002. We sampled vegetation structure at the same sites by measuring horizontal (tree species and density in different size classes) and vertical (percentage canopy closure in dominant, intermediate, suppressed and shrub layer) characteristics within 0.04 ha circular plots centred on the established points. Univariate and multivariate statistical techniques were employed to examine the response of the turtledove′s presence to habitat differences between used and unused sites. The results of this study indicate that habitat structure influence the presence of the turtledove during the breeding season. Middle-aged forest stands particularly those dominated by pine trees with low percentage cover in understory are likely to be beneficial to breeding the turtledove population. A combination of multipurpose forestry operations allowing development of managed woodland in mosaics with other habitat types could provide high-quality habitats for a wide range of wildlife species including game and non-game species in the area. Silvicultural methods of maintaining appropriate breeding habitat for turtledove in Dadia-Lefkimi-Soufli National Park (DLS NP), which are in conflict with commercial forestry, are discussed.

We would like to take this opportunity to welcome readers to this new journal Conservation Science and provide an overview of its aim at what we believe is an exciting venue for conservationists worldwide.