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Under different environmental conditions, hybridization between the same species might result in different patterns of genetic admixture. Particularly, species pairs with large distribution ranges and long evolutionary history may have experienced several independent hybridization events over time in different zones of overlap. In birds, the diverse hybrid populations of the house sparrow (Passer domesticus) and the Spanish sparrow (Passer hispaniolensis) provide a striking example. Throughout their range of sympatry, these two species do not regularly interbreed; however, a stabilized hybrid form (Passer italiae) exists on the Italian Peninsula and on several Mediterranean islands. The spatial distribution pattern on the Eurasian continent strongly contrasts the situation in North Africa, where house sparrows and Spanish sparrows occur in close vicinity of phenotypically intermediate populations across a broad mosaic hybrid zone. In this study, we investigate patterns of divergence and admixture among the two parental species, stabilized and nonstabilized hybrid populations in Italy and Algeria based on a mitochondrial marker, a sex chromosomal marker, and 12 microsatellite loci. In Algeria, despite strong spatial and temporal separation of urban earlybreeding house sparrows and hybrids and rural late‐breeding Spanish sparrows, we found strong genetic admixture of mitochondrial and nuclear markers across all study populations and phenotypes. That pattern of admixture in the North African hybrid zone is strikingly different from i) the Iberian area of sympatry where we observed only weak asymmetrical introgression of Spanish sparrow nuclear alleles into local house sparrow populations and ii) the very homogenous Italian sparrow population where the mitogenome of one parent (P. domesticus) and the Z‐chromosomal marker of the other parent (P. hispaniolensis) are fixed. The North African sparrow hybrids provide a further example of enhanced hybridization along with recent urbanization and anthropogenic land‐use changes in a mosaic landscape.

International audience; Knowledge of patterns of occupancy is crucial for planning sound biological management and for identifying areas which require paramount conservation attention. The European wildcat Felis silvestris is an elusive carnivore and is classified as ‘least concern' on the IUCN red list, but with a decreasing population trend in some areas. Sicily hosts a peculiar wildcat population, which deserves conservation and management actions, due to its isolation from the mainland. Patterns of occupancy for wildcats are unknown in Italy, and especially in Sicily. We aimed to identify which ecological drivers determined wildcat occurrence on Mt Etna and to provide conservation actions to promote the wildcats’ long-term survival in this peculiar environment. The genetic identity of the wildcat population was confirmed through a scat-collection which detected 22 different wildcat individuals. We analysed wildcat detections collected by 91 cameras using an occupancy frame work to assess which covariates influenced the detection (p) and the occupancy (ψ) estimates. We recorded 70 detections of the target species from 38 cameras within 3377 trap-days. Wildcat detection was positively influenced by the distance to the major paved roads and negatively affected by the presence of humans. Wildcat occupancy was positively associated with mixed forest and negatively influenced by pine forest, fragmentation of mixed forest and altitude. A spatially explicit predicted occupancy map, validated using an independent dataset of wildcat presence records, showed that higher occupancy estimates were scattered, mainly located on the north face and at lower altitude. Habitat fragmentation has been claimed as a significant threat for the wildcat and this is the first study that has ascertained this as a limiting factor for wildcat occurrence. Conservation actions should promote interconnectivity between areas with high predicted wildcat occupancy while minimising the loss of habitat.

African clawed frogs of the widespread polytypic species Xenopus laevis Daudin, 1802 (ranging large parts of sub-Saharan Africa) have been spreading since the 1940s, and have established reproductive populations in Europe, Asia and the Americas, where they can have negative impact as competitors of native amphibians and as disease vectors for chytridomycosis or ranaviruses. Here we use two mitochondrial (cytochrome b, 16S rDNA) and one nuclear (RAG 1: Recombination Associated Gene 1) DNA markers to infer the potential origin of invasive clawed frogs from Sicily that represent the largest invasive population in Europe. Identical mtDNA haplotypes match with those of Xenopus laevis, and Sicilian clawed frogs very probably belong to a lineage from the Cape Region of South Africa, most likely originating from a laboratory stock. Nuclear data support this conclusion. Identical mtDNA sequences (cyt b, 16S) of frogs sampled across their range in Sicily suggest the occurrence of a single source population and a potential bottleneck at their release, but faster evolving multilocus nuclear data (microsatellites, SNPs) on the population genetics would be important in the future to better support this hypothesis. © 2013 Unione Zoologica Italiana.

In this study, a phylogeographic scenario of the coal tit (Periparus ater) was reconstructed based on a fragment of the mitochondrial control region, and within- and between-population genetic diversity was analysed with a focus on the western Palearctic breeding range. We inferred a first pan-European delimitation of a postulated secondary contact zone among coal tits from the north-eastern Palearctic ater subspecies group and those from the south-western Palearctic abietum group. Generally, between-population differentiation was greatest in the Mediterranean range, which was explained by a greater separation in multiple Pleistocene refuge areas compared to the lower differentiation across the north-eastern Palearctic range. Genetic diversity indices were lowest on Mediterranean island populations as compared to continental populations. Pairwise ΦST values were highest among island populations and the Eurasian continent on the one hand and among the continental north-eastern ater and south-western abietum group on the other. Local co-occurrence of ater and abietum haplotypes was found all across Germany and in one Greek population. Molecular dating suggested that these two major subspecies groups separated from each other and from two further North African and Middle Eastern coal tit lineages during the early to mid-Pliocene. Successively, the Mediterranean region remained a centre of mainly insular diversification until late Pleistocene times including a long period of steady population growth. At the same time, at least four distinct genetic lineages emerged in eastern Eurasia, the nominate ater subspecies group being one of them. Finally, during the Holocene extant wide-range secondary contact in Europe was established via rapid westward range expansion from an East Asian refuge and via northeastward expansion from Mediterranean refuges. © 2012 Elsevier GmbH.

Capsule: We report a significant reduction in population size and breeding success for the Lanner Falcon Falco biarmicus in Sicily, its biggest stronghold in Europe, since the latest coordinated survey. Aims: To provide updated information on current population size of Lanner Falcon in Sicily and to compare breeding parameters with those obtained in previous studies. Methods: We performed an intensive coordinated field survey and literature review of breeding success parameters across the species range. Results: Overall, we monitored 126 territories throughout Sicily where the species had been reported in the last 15 years. Lanner Falcons were present only in 60 of them. Mean nest productivity (± standard deviation) was 1.09 ± 1.18 fledged young/checked pairs, flight rate was 2.22 ± 0.52 fledged young/successful pairs and breeding success was 49.0%. Conclusions: Indirect measures aimed at preventing abandonment of occupied territories should be applied, for instance by developing a network of priority areas and slowing down degradation of the pseudo-steppe habitats by agri-environmental schemes. Additionally, direct measures aimed at preventing nest robbery, including the organization of nest guarding activities, and reduction of anthropogenic disturbance and illegal shooting, must be encouraged in order to avoid territory abandonment.

Illegal trade in wildlife has been identified as one of the main challenges to wildlife conservation. In 2010, an illegal trade-ring trafficking in birds of prey was uncovered in Sicily (southern Italy). This illegal trade targeted the three most endangered species in Italy: Bonelli's eagle Aquila fasciata, Lanner falcon Falco biarmicus and Egyptian vulture Neophron percnopterus, all of them long-lived territorial raptors threatened with extinction across their European distribution. Illegal harvest primarily involved young birds and eggs taken from nests. After the discovery of these activities, surveillance camps and camera traps connected to the mobile Global System for Mobile communications network were established in nine Bonelli's eagle breeding sites in which illegal harvest was reported. Surveillance activities resulted in a sharp reduction in illegal harvest that has contributed to the recent increase in population size and number of breeding pairs of Bonelli's eagle in the island. This population represents 95% of the entire Italian population and is catalogued as Critically Endangered in this country. Importantly, our results highlight the impact of illegal harvest on the population dynamics of endangered species as demonstrated by a population viability analysis. This is particularly important in the case of insular species for which demographic recovery due to immigration from other geographic areas is unlikely. Systematic patrols by forestry police authorities, a resolute application of Convention on International Trade in Endangered Species legislation via legal punishment, and the requirement of including all live captive specimens used for falconry in an obligatory DNA data bank would contribute to reducing the risk of extinction for small populations of endangered species of birds of prey.

The European rabbit Oryctolagus cuniculus (O.c) lives all over the world and it represents an important resource for many predators. It has been classified as a Near-Threatened species in the Red List of Vertebrates of Italy. It is present in mediterranean basin as two known subspecies: O.c. cuniculus and O.c. algirus. The mediterranean geographic distribution of the two subspecies is still not well known. In particular, in Sicily, lacking of deep studies, is based on the body size and morphological characteristics; there wasn’t a complete description of the actual existing subspecies and previous studies only reported the morphological characteristics of the sicilian rabbit population. In this study, we analyzed genetic data, mitochondrial (mt) cytochrome b (cytb), from the rabbit population in Sicily in a phylogenetic framework. This is the first study concerning the genetics of the sicilian rabbit, to reconstruct intraspecific phylogeny by comparing cytb mtDNA sequences of 13 newly isolated O.cuniculus haplotypes from Sicily and 7 individuals from other countries (Canada, France, Mexico, North Italy, South Africa, Spain, Sweden). Our results show that the rabbit population from Sicily has a mitochondrial type (Lineage B) that has been previously shown to be associated with O. c. cuniculus and is similar to sequences from rabbits in North-Est Spain, Southern France, Sweden and South Africa.

The conservation status of amphibians is often assessed using public databases because of a lack of up-to-date field data. However, it is crucial that this kind of data is used carefully, evaluating the reliability and the consistency of the information. In Italy, the conservation status of the painted frog, Discoglossus pictus, was recently assessed using public databases, and the outcome highlighted a worrying situation for the species. We analyzed the reliability of these conclusions and reassessed the status of the painted frog, taking into account its insular distribution and new data of species occurrence. Our results contrast with the previous analysis and show how an incautious use of public databases can lead to inaccurate assessment of the amphibian conservation status.

International audience; Estimating the genetic variation and demographic trends of species in decline is of major concern in conservation genetics. This study contributes to understanding how historical and anthropogenic factors shape the distribution of current genetic diversity in one of the most endangered reptiles in Western Europe, the Hermann's tortoise Testudo hermanni hermanni. We used 17 microsatellite loci, chosen from a pyrosequencing library specifically developed for the subspecies to genotype eight populations distributed over about 30 sample localities covering almost the entire geographic distribution of the sub-species. The population genetic results reflect a very strong genetic structure and identify three major clusters among the Hermann's tortoise in the occidental Mediterranean basin: a continental cluster (Albera in Spain, Var in France and continental Italy), an insular cluster (Corsica, Sardinia and Sicily) and a cluster of mixed lineage (Minorca). Each of the eight studied populations is characterized by only one lineage except for Minorca, in which two lineages were identified. In contrast to what most empirical studies predict, the genetic diversity of the Hermann's tortoise is greater on islands than on the continent. Islands can therefore be considered as genetic sanctuaries with high conservation potential for this species, particularly in Corsica. Historical demographic patterns inferred with a generalized stepwise-mutation model (GSM) using maximum likelihood showed significant past demographic changes in only two of the eight sampled populations: a demographic bottleneck was detected in the Albera population (Spain) and a demographic expansion in Corsica (France). In contrast to what was argued in previous studies, these results indicate that the Hermann's tortoise lineage found in Corsica is autochthonous. The origin of both lineages found in Minorca remains speculative. Lastly, our study identifies the six most relevant management units (sensu Moritz, 1994) for conservation purposes on the basis that they represent a significant part of the evolutionary legacy of the species. Some conservation recommendations were proposed, in particular for the most threatened population in Albera.

Biological invasions are regarded as a form of global change and potential cause of biodiversity loss. Xenopus laevis is an anuran amphibian native to sub-Saharan Africa with strong invasive capacity, especially in geographic regions with a Mediterranean climate. In spite of the worldwide diffusion of X. laevis, the effective impact on local ecosystems and native amphibian populations is poorly quantified. A large population of X. laevis occurs in Sicily and our main aim of this work was to assess the consequences of introduction of this alien species on local amphibian populations. In this study we compare the occurrence of reproduction of native amphibians in ponds with and without X. laevis, and before and after the alien colonization. The results of our study shows that, when X. laevis establishes a conspicuous population in a pond system, the populations of Discoglossus pictus, Hyla intermedia and Pelophylax synklepton esculentus show clear signs of distress and the occurrence of reproduction of these native amphibians collapses. In contrast, the populations of Bufo bufo do not appear to be affected by the alien species. Since the Sicilian population of X. laevis shows a strong dispersal capacity, proportionate and quick interventions become necessary to bound the detriment to the Sicilian amphibians populations.

The breeding performance and foraging of blue and great tits, and the abundance of arthropods living on the trees of an oak-wood and of a coniferous reafforestation were studied in Sicily, in order to: 1) compare breeding parameters in natural and semi-natural habitats within the same area; 2) estimate the degree of overlap in peak resource and peak demand of young tits, and the overlap of nestling diet of the two species in the two habitats. Both species had earlier laying dates, laid more eggs and raised more fledglings in the oakwood than in the reafforestation; they achieved the same fledging success within the same habitat type. These differences are probably due to the earlier and higher food peak in oak compared to pine. Food brought to the nestlings differed between habitats and between species: blue tits always brought small prey from a limited number of taxa, while great tits changed both prey taxa and size depending on habitat. The more flexible food of the great tit is in line with the smaller reduction in number of fledglings in pine reafforestation compared to oak-wood. It is suggested that tits have developed a mechanism to lay eggs at different dates in accordance with the habitat resource where adults catch prey for nestlings. Finally, mean clutch sizes of blue tits between habitats were well correlated, but the process seemed different in the great tit. Significant correlation was indeed detected between the proportion of great tits breeding in oakwood and the difference in the clutch size between the habitats. This suggests that more great tits settled in oakwood in years when conditions were more suitable to produce bigger clutches. © 2004 Taylor & Francis Group, LLC.

Using virtually range-wide sampling for three pond turtle taxa (Emys orbicularis galloitalica, E. o. hellenica, E. trinacris), we analyse gene flow across their southern Italian contact zone. Based on population genetic analyses of 15 highly polymorphic microsatellite loci and a mitochondrial marker, we show that the general genetic pattern matches well with the current taxon delimitation. Yet, single individuals with conflicting genetic identity suggest translocation of turtles by humans. In addition, we identify in south-western France and the vicinity of Rome populations being heavily impacted by introduced turtles. Cline analyses reveal that the major genetic break between E. o. galloitalica and E. o. hellenica corresponds well with the currently accepted intergradation zone in southern Italy. However, introgression is largely unidirectional from E. o. galloitalica into E. o. hellenica. In the distribution range of the latter subspecies, genetic footprints of E. o. galloitalica are evident along most of the Italian east coast. Our results corroborate that E. o. galloitalica was introduced long ago in Corsica and Sardinia and naturalized there. Gene flow between E. orbicularis and E. trinacris is negligible, with the Strait of Messina matching well with the narrow cline centre between the two species. This contrasts with other Mediterranean freshwater turtle species with extensive transoceanic gene flow. Compared to the two subspecies of E. orbicularis, the Sicilian E. trinacris shows an unexpectedly strong population structuring, a finding also of some relevance for conservation. The differences between the two taxon pairs E. orbicularis/E. trinacris and E. o. galloitalica/E. o. hellenica support their current taxonomic classification and make them attractive objects for follow-up studies to elucidate the underlying mechanisms of speciation by comparing their properties.

In most pan-Eurasiatic species complexes, two phenomena have been traditionally considered key processes of their cladogenesis and biogeography. First, it is hypothesized that the origin and development of the Central Asian Deserts generated a biogeographic barrier that fragmented past continuous distributions in Eastern and Western domains. Second, Pleistocene glaciations have been proposed as the main process driving the regional diversification within each of these domains. The European common toad and its closest relatives provide an interesting opportunity to examine the relative contributions of these paleogeographic and paleoclimatic events to the phylogeny and biogeography of a widespread Eurasiatic group. We investigate this issue by applying a multiproxy approach combining information from molecular phylogenies, a multiple correspondence analysis of allozyme data and species distribution models. Our study includes 304 specimens from 164 populations, covering most of the distributional range of the Bufo bufo species complex in the Western Palearctic. The phylogenies (ML and Bayesian analyses) were based on a total of 1988 bp of mitochondrial DNA encompassing three genes (tRNAval, 16S and ND1). A dataset with 173 species of the family Bufonidae was assembled to estimate the separation of the two pan-Eurasiatic species complexes of Bufo and to date the main biogeographic events within the Bufo bufo species complex. The allozyme study included sixteen protein systems, corresponding to 21 presumptive loci. Finally, the distribution models were based on maximum entropy. Our distribution models show that Eastern and Western species complexes are greatly isolated by the Central Asian Deserts, and our dating estimates place this divergence during the Middle Miocene, a moment in which different sources of evidence document a major upturn of the aridification rate of Central Asia. This climate-driven process likely separated the Eastern and Western species. At the level of the Western Palearctic, our dating estimates place most of the deepest phylogenetic structure before the Pleistocene, indicating that Pleistocene glaciations did not have a major role in splitting the major lineages. At a shallow level, the glacial dynamics contributed unevenly to the genetic structuring of populations, with a strong influence in the European–Caucasian populations, and a more relaxed effect in the Iberian populations., The first author is recipient of a pre-doctoral research fellowship (JAE) from the CSIC. The work was partially funded by Grants CGL2008-00827 and CGL2009-11663 from the Ministerio de Educación y Ciencia, Spain to SC. S.N. Litvinchuk was partly supported by Grants NSh-3299.2010.4 and MCB-N22n.

Evolutionary studies on optimal decisions or conservation guidelines are often derived by generalising patterns from a single population, while inter-population variability in life-history traits is seldom considered. We investigated here how survival and recruitment probabilities changed with age at different geographical scales using the encounter histories of 5523 European storm petrels from three Mediterranean colonies, and also how our estimates of these parameters might be expected to affect population growth rates using population matrix models. We recorded similar patterns among colonies, but also important biological differences. Local survival, recruitment and breeding success increased with age at all colonies; the most distant of three colonies (Marettimo Is.) showed the largest differences. Strikingly, differences in recruitment were also found between two adjacent colonies (two caves from Benidorm Is.). Birds marked as adults from Marettimo and Benidorm colonies had a different survival, whereas we found no differences within Benidorm. Differences in survival were no longer apparent between the two islands at the end of the study following a reduction in predation by specialist gulls at Benidorm. Since birds marked as fledglings mostly recruited near the end of the study, their overall survival was high and in turn similar among colonies. Results from our population matrix models suggested that different age-dependent patterns of demographic parameters can lead to similar population growth rates. Variability appeared to be greater for recruitment and the most sensitive parameter was adult survival. Thus conservation actions targeting this vulnerable species should focus on factors influencing adult survival. Differences in survival and recruitment among colonies could reflect the spatial heterogeneity in mortality due to predation and colony-specific density dependent processes. Results highlight the importance of taking into account the potential spatio-temporal heterogeneity among populations in vital rates, even in those traits that life-history theory considers less important in driving population dynamics. © 2009 Ecography., The Spanish Ministry of Science, funded the study through several grants (refs. BOS2003-01960, CGL2006-04325/BOS)

The worldwide spread of invasive species is considered to be one of the main causes of global amphibian declines and the loss of biodiversity in general. The African Clawed Frog, Xenopus laevis, shows a strong ability to establish populations and invade various geographic regions. In 2004 X. laevis was found in Sicily for the first time. The Sicilian population is probably the largest in Europe with a range of about 225 km2 in an area characterized by numerous agricultural ponds. This high density of ponds has potentially facilitated the dispersal of X. laevis. The frogs can move far from rivers or watercourses by utilizing the ponds as suitable "islands". The analysis of their diet shows that the aquatic larvae of nektonic insects comprise the major portion in terms of mass while small planktonic crustaceans are the most numerous component. There is a significant difference between the diet of adults and juveniles.