The Boar War: Five Hot Factors Unleashing Boar Expansion and Related Emergency

The recent and ever-growing problem of boar (Sus scrofa forms including wild boar, hybrid and feral pig) expansion is a very complex issue in wildlife management. The damages caused to biodiversity and the economies are addressed in different ways by the various countries, but research is needed to shed light on the causal factors of this emergency before defining a useful collabora- tive management policy. In this review, we screened more than 280 references published between 1975–2022, identifying and dealing with five hot factors (climate change, human induced habitat mod- ifications, predator regulation on the prey, hybridization with domestic forms, and transfaunation) that could account for the boar expansion and its niche invasion. We also discuss some issues arising from this boar emergency, such as epizootic and zoonotic diseases or the depression of biodiversity. Finally, we provide new insights for the research and the development of management policies

Eating in extreme environment: diet of the European hare (Lepus europaeus) on Vesuvius

The European hare (Lepus europaeus) is cosmopolitan species, living in a variety of habitats and showing a diversified diet, that has been described mainly from agricultural meadows and crops, with little information available for extreme environments. Here, we describe, for the first time, the diet of the European hare from Mount Vesuvius, using DNA metabarcoding and high- throughput sequencing on DNA extracted from faecal pellets, a proxy for a population living in a volcanic environment. The DNA from pellets was first genetically assigned to European hare using high-resolution melting analysis. The diet of the hare on Vesuvius is mainly composed of herbaceous species belonging to Fabaceae (86.26% of total diet). The most frequent plant items ingested by the species are Galega officinalis and Lupinus angustifolius (67.10% of total diet), although these are detected only sporadically in the study area. Indeed, the spectrum of available plants also includes other easily accessible wild (i.e. Lolium sp., Bromus sp., Rumex sp.) and cultivated (i.e. Solanum lycopersicum, Cucumis melo, Pisum sativum) plant items, found only in traces in the diet of the hares. Our contribution adds information on the trophic ecology of the European hare, exploring its ability to live in an extreme environment. This could be useful to set a management strategy for conservation of the species, which is ecologically relevant on Vesuvius as prey for birds and mammals, as well as a vegetation modulator via selective grazing by endozoochory. Furthermore, our study represents the latest information on the diet of the hare living in an environment that no longer exists: an extensive fire destroyed about 80% of the woody area after our sampling. The post-fire regrowth is transforming the original environment and consequently the trophic availability for the European hare

Population development and landscape preference of reintroduced wild ungulates: successful rewilding in Southern Italy

Background: In the past decades, the abandonment of traditional land use practices has determined landscape changes inducing reforestation dynamics. This phenomenon can be contrasted with rewilding practices, i.e., the reintroduction of animals that may promote the recovery of landscape diversity. In this study, we explore the dynamics of expansion of two reintroduced populations of wild ungulates, Italian roe deer (Capreolus capreolus italicus) and red deer (Cervus elaphus), assessing their contribution in the recovery of landscape diversity. Methods: By using direct and indirect information on the two species, collected by nocturnal and diurnal surveys and camera trapping, we modelled a habitat suitability map, and estimated the density and distribution of the populations. We also performed a land use changes analysis, combining the presence of wild ungulates and livestock. Results and discussion: We demonstrated that deer dispersed gradually from their release location, increasing in population size, and this occurred in the entire study area. Moreover, we show that areas with lower grazing density are significantly affected by forest encroachment. A possible interpretation of this result could be that wild grazers (roe deer and red deer) prefer semi-open areas surrounded by the forest. This, in association with other factors, such as domestic grazing, could be one of the main responsible in maintaining landscape mosaic typical of the Apennine mountain, confirming the value of grazers as a landscape management tool. Moreover, we show the possibility to conserve through reintroduction the vulnerable C.c. italicus

Southern Italian wild boar population, hotspot of genetic diversity

The wild boar, Sus scrofa, is an important game species widely distributed in Eurasia. Whereas the genetic variability of most European wild boar populations is well known, the status of wild boar living in Southern Italy is not as clear. We evaluated the present and past genetic diversity (D-loop, mtDNA) of the South Italian population, comparing it with that observed in other Mediterranean glacial refugia. Italian population showed highest genetic variability, if compared to other two European refugia (Iberian and Balkan). Most of samples from Italy carried sequences belonging to the European E1 haplogroup (80.9%) with a small proportion of the private Italian E2 (10.2%) and of the Asian (8.9%) ones. Italian samples carrying an Asian haplotype were genotyped by MC1R nuclear gene, failing to disclose a recent introgression from domestic pigs. Mismatch distribution analysis of the Italian population was affected by secondary contacts between these different lin- eages. This genetic melting pot was detected since the Mesolithic and the Neolithic age, during which we found samples belonging to the indigenous Italian and European haplogroups. Further, a Near-Eastern haplotype was found in 1,800 AD samples from Southern and Central Italy. Our res- ults can be in agreement with post-glacial recolonization theories, as well as with the long history of human-mediated translocations of Sus scrofa in the Mediterranean basi

The blue lizard spandrel and the island syndrome

<p>Abstract</p> <p>Background</p> <p>Many small vertebrates on islands grow larger, mature later, lay smaller clutches/litters, and are less sexually dimorphic and aggressive than their mainland relatives. This set of observations is referred to as the 'Island Syndrome'. The syndrome is linked to high population density on islands. We predicted that when population density is low and/or fluctuating insular vertebrates may evolve correlated trait shifts running opposite to the Island Syndrome, which we collectively refer to as the 'reversed island syndrome' (RIS) hypothesis. On the proximate level, we hypothesized that RIS is caused by increased activity levels in melanocortin receptors. Melanocortins are postranslational products of the proopiomelanocortin gene, which controls pleiotropically pigmentation, aggressiveness, sexual activity, and food intake in vertebrates.</p> <p>Results</p> <p>We tested the RIS hypothesis performing a number of behavioral, genetic, and ontogenetic tests on a blue colored insular variant of the Italian Wall lizard <it>Podarcis sicula</it>, living on a small island off the Southern Italian coast. The population density of this blue-colored variant was generally low and highly fluctuating from one year to the next.</p> <p>In keeping with our predictions, insular lizards were more aggressive and sexually dimorphic than their mainland relatives. Insular males had wide, peramorphic heads. The growth rate of insular females was slower than growth rates of mainland individuals of both sexes, and of insular males. Consequently, size and shape dimorphism are higher on the Island. As predicted, melanocortin receptors were much more active in individuals of the insular population. Insular lizards have a higher food intake rate than mainland individuals, which is consistent with the increased activity of melanocortin receptors. This may be adaptive in an unpredictable environment such as Licosa Island. Insular lizards of both sexes spent less time basking than their mainland relatives. We suspect this is a by-product (spandrel) of the positive selection for increased activity of melanocortins receptors.</p> <p>Conclusions</p> <p>We contend that when population density is either low or fluctuating annually as a result of environmental unpredictability, it may be advantageous to individuals to behave more aggressively, to raise their rate of food intake, and allocate more energy into reproduction.</p

Seeing through the skin: dermal light sensitivity provides cryptism in moorish gecko

Concealment by means of colour change is a pre-eminent deceptive mechanism used by both predators and prey. The moorish gecko Tarentola mauritanica is able to blend into the background by either darkening or paling according to the substrate darkness. Here we examined the functioning of background perception in moorish gecko. We experimentally excluded the involvement of melanophore-stimulating hormone in camouflage. Blindfolded individuals change their colour consistently with the background. Surprisingly, individuals with covered flanks were not able to change colour, no matter whether they were allowed to see the substrate or not. Accordingly, we found high levels of opsin transcript and protein in the flank region of the gecko. These observations suggest that T.mauritanica skin melanophores are able to activate a process of colour change autonomously. This study yields the first evidence of crypsis mediated by dermal light sensitivity in amniote

Spatial genetic structure in the Eurasian otter (Lutra lutra) meta-population from its core range in Italy

We characterized the genetic structure of the Eurasian otter (Lutra lutra) meta-population living in the core of its Italian distribution range providing results from 191 fresh spraints, collected from 24 watercourses included in Southern Italy. Furthermore, according to ecological corridors and barriers, we discuss the likely ways of movement and possible evolutionary fate of these populations. We genotyped 136 samples using 11 Lut microsatellite nuclear markers amplified from faecal dna. Microsatellites were moderately variable (Ho = 0.45; He = 0.46), with a total number of alleles and average number of alleles per locus in the meta-population of 50 and 4.54, respectively. No significant heterozygosity excess was observed in meta-population suggesting no recent population bottlenecks. Bayesian clustering discriminated a sub-structuring of the meta-population in five putative clusters, indicating that local populations are genetically differentiated: three of these seem to be identifiable with geographically defined sub-populations (from the Cilento, Agri and Basento river basins). The fourth is represented by multiple sub-populations with admixed genotype, that include genotypes from the Lao, Sinni and Abatemaco river basins, living in a landscape with the higher environmental permeability. Landscape genetic analysis could provide evidence of an unexpected ecological corridor: the seacoast, highlighted, for the first time as a new way for the dispersion of the South-Italian otters. Deepening the knowledge of these perspectives is crucial to identify solid strategies aimed at the future health of the populations of the Italian otters, by restoring dispersal corridors and managing the watercourses

Contribution to the ecology of the Italian hare (Lepus corsicanus)

the italian hare (Lepus corsicanus) is endemic to Central-Southern Italy and Sicily, classified as vulnerable due to habitat alterations, low density and fragmented populations and ecological competition with the sympatric european hare (Lepus europaeus). Despite this status, only few and local studies have explored its ecological features. We provided some key traits of the ecological niche of the italian hare as well as its potential distribution in the italian peninsula. All data derived from genetically validated presences. We generated a habitat suitability model using maximum entropy distribution model for the italian hare and its main competitor, the european hare. the dietary habits were obtained for the italian hare with DnA metabarcoding and High-throughput Sequencing on faecal pellets. The most relevant environmental variables affecting the potential distribution of the italian hare are shared with the european hare, suggesting a potential competition. the variation in the observed altitudinal distribution is statistically significant between the two species.The diet of the Italian hare all year around includes 344 plant taxa accounted by 62 families. The Fagaceae, Fabaceae, Poaceae, Rosaceae and Solanaceae (counts &gt; 20,000) represented the 90.22% of the total diet. Fabaceae (60.70%) and Fagaceae (67.47%) were the most abundant plant items occurring in the Spring/Summer and Autumn/Winter diets, respectively. the Spring/Summer diet showed richness (N = 266) and diversity index values (Shannon: 2.329, Evenness: 0.03858, Equitability: 0.4169) higher than the Autumn/Winter diet (N = 199, Shannon: 1.818, Evenness: 0.03096, Equitability: 0.3435). Our contribution adds important information to broaden the knowledge on the environmental (spatial and trophic) requirements of the Italian hare, representing effective support for fitting management actions in conservation planning

Selection for background matching drives sympatric speciation in Wall Gecko

The Wall Gecko shows heterogeneous colour pattern, which may vary among individuals, depending on the time of day and on the habitat segregation. Nocturnal pale geckos live exclusively on walls. Diurnal dark geckos preferentially live on olive tree trunks, demonstrating an ability to change skin colour that is superior to that of the pale gecko and allows diurnal geckos becoming camouflaged on the diverse substrates occupied during the day. In our study, the nocturnal/pale/wall and diurnal/dark/trunk geckos could be considered the extremes of an ecological cline of morphological variation on which divergent selection may be acting. Combining the effect of balancing selection on nocturnal geckos and disruptive selection between two sympatric populations could lead to speciation. All geckos analysed here belong to the same species, as confirmed by genetic characterization, however diurnal and nocturnal gecko populations seem to be in an early stage of incipient speciation. These two different morphs still combine genes, as revealed by neutral genetic markers, yet they show complete separation according to the analyses of mtDNA coding genes. Experimental results show that diurnal and nocturnal geckos do not swap their niches, likely because the predation pressure causes severe selection for background matching. Genomic analysis of complete mtDNA suggests that nocturnal geckos seem to be under balancing selection perhaps due to the narrow niche in which they live, whereas the daytime population has more opportunity in fitting into the multiple available niches, and they experience positive selection. Here we hypothesize that the ecological segregation that we are witnessing between the nocturnal and diurnal geckos, can lead to a ecological speciation

The first transcriptome of Italian wall lizard, a new tool to infer about the Island Syndrome

Some insular lizards show a high degree of differentiation from their conspecific mainland populations, like Licosa island lizards, which are described as affected by Reversed Island Syndrome (RIS). In previous works, we demonstrated that some traits of RIS, as melanization, depend on a differential expression of gene encoding melanocortin receptors. To better understand the basis of syndrome, and providing raw data for future investigations, we generate the first de novo transcriptome of the Italian wall lizard. Comparing mainland and island transcriptomes, we link differences in life-traits to differential gene expression. Our results, taking together testis and brain sequences, generated 275,310 and 269,885 transcripts, 18,434 and 21,606 proteins in Gene Ontology annotation, for mainland and island respectively. Variant calling analysis identified about the same number of SNPs in island and mainland population. Instead, through a differential gene expression analysis we found some putative genes involved in syndrome more expressed in insular samples like Major Histocompatibility Complex class I, Immunoglobulins, Melanocortin 4 receptor, Neuropeptide Y and Proliferating Cell Nuclear Antigen