Maurizio Sarà

Phylogeographical footprints of the Strait of Gibraltar and Quaternary climatic fluctuations in the western Mediterranean: a case study with the greater white-toothed shrew, Crocidura russula (Mammalia: Soricidae).

We used mitochondrial cyt b sequences to investigate the phylogenetic relationships of Crocidura russula (sensu lato) populations across the Strait of Gibraltar, western Europe, Maghreb, and the Mediterranean and Atlantic islands. This revealed very low genetic divergence between European and Moroccan populations. The application of a molecular clock previously calibrated for shrews suggested that the separation of European from Moroccan lineages occurred less than 60 000 bp, which is at least 5 million years (Myr) after the reopening of the Strait of Gibraltar. This means that an overwater dispersal event was responsible for the observed phylogeographical structure. In contrast, genetic analyses revealed that Moroccan populations were highly distinct from Tunisian ones. According to the molecular clock, these populations separated about 2.2 million years ago (Ma), a time marked by sharp alternations of dry and humid climates in the Maghreb. The populations of the Mediterranean islands Ibiza, Pantelleria, and Sardinia were founded from Tunisian populations by overwater dispersal. In conclusion, overwater dispersal across the Strait of Gibraltar, probably assisted by humans, is possible for small terrestrial vertebrates. Moreover, as in Europe, Quaternary climatic fluctuations had a major effect on the phylogeographical structure of the Maghreb biota.

A comparison of the structure of helminth communities in the woodmouse, Apodemus sylvaticus, on islands of the western Mediterranean and continental Europe

We investigated the pattern of helminth species diversity in woodmouse, Apodemus sylvaticus, on western Mediterranean islands. We first performed a survey of the helminth fauna of A. sylvaticus in Sicily. Despite the small sampling effort, parasite species richness in Sicily is large in comparison with parasite species richness on other Mediterranean islands. We tested the nestedness of helminth parasite species from a number of Mediterranean localities using data compiled from epidemiological surveys of the helminth species of A. sylvaticus. We showed a nested pattern for woodmouse helminth species on western Mediterranean islands which suggests that the distribution of parasites on these islands is not the result of a random process. Properties of helminth parasites such as taxonomic group or life cycle and properties of the host population localities such as area size or the stability of the environment (estimated by mammal species diversity) contribute to the nestedness.

Factors influencing the distribution, abundance and nest‐site selection of an endangered Egyptian vulture (Neophron percnopterus) population in Sicily

The Egyptian vulture ( Neophron percnopterus ) breeds in Sicily and, in 22 years of monitoring, has shown a decline followed by a slight recovery. We used Generalised Linear Models to predict: (1) the distribution range, (2) the habitat selection within the range, (3) the quality (i.e., occupation rate, breeding success) of breeding sites. Some 60% of Sicily proved to be unsuitable, being either too densely forested and without cliffs for nesting, or too densely populated, along with intensive agriculture. The models converged, indicating that the pairs select a precise upland habitat where low cliffs, distant from urban areas, are surrounded by arboreal crops and Mediterranean vegetation. The variables predicting the quality of a site are also related to human disturbance, including the distance from a road or the presence of heavy traffic. Natural restocking, in the last 3 years, is occurring in quiet sites and in proximity to extensive grazing land rich in sheep and goat herds. These results focused on short-term programmes for local management of the species aimed at protracting the natural restocking: namely, the activation of (1) a stable system of artificial feeding stations, (2) nest site protection with joint activities for increasing public awareness, (3) a reintroduction project, by hacking, of juveniles born in captivity in Italian and European breeding centres.

Comparative morphometrics of sharpsnout seabream (Diplodus puntazzo Cetti, 1777), reared in different conditions

The same genetic stock of sharpsnout seabream (Diplodus puntazzo), cultured in different conditions (lot A, monoculture tank; lot B, monoculture offshore cage; lot C, polyculture tank), was analysed using geometric morphometrics in order to detect changes in shape. Rearing in the offshore cage (lot B) had a significant effect on shape variation when compared to rearing in the two enclosed tanks (A and C). Fish from the tanks show a higher frequency (43.7% in lot A and 37.5% in lot C) of the so-called ‘goitred’ and ‘dorsal flat’ forms, their deformations shown by displacements in the corresponding landmarks of the infraopercular and dorsal areas. In contrast, the so-called ‘belly’ fish were more numerous in lot B (66.7%). These changes in shape are mostly related to a non-uniform variation (i.e. not due to shearing and dilation but localised in some body areas) and the differences were shown to be statistically significant between the lots. Finally, more than 90% of the variation in shape was left unexplained by the regressions of shape variables over size (expressed as weight in grams and centroid size). Change in shape does not seem to be strictly dependent on increasing size is therefore likely to be determined by culture conditions.

Mitochondrial phylogeography of the edible dormouse (Glis glis) in the western Palearctic region

Abstract This study describes in detail the phylogeographic pattern of the edible dormouse (Glis glis) a European rodent with pronounced hibernating behavior. We used sequences of 831 base pairs of the mitochondrial DNA cytochrome-b gene from 130 edible dormice collected at 43 localities throughout its distribution. Our results reveal presence of 3 main haplogroups: Sicilian, South Italian (restricted to the Calabrian region), and European (a widespread lineage corresponding to all remaining western, central, and eastern European populations). Examination of paleontological data confirms refugial regions for G. glis in the 3 Mediterranean peninsulas, although overall low genetic diversity is found. The low diversity of the European lineage is probably the result of a recent expansion (dated around 2,000 years ago) from a single refugium. Other factors, such as the ecological constraints on the species, may have caused genetic bottlenecks that reinforced the low genetic variability of G. glis. This work could have important implications for strategies to conserve the edible dormouse by defining important areas for their conservation.

Exploitation competition between hole-nesters ( Muscardinus avellanarius , Mammalia and Parus caeruleus , Aves) in Mediterranean woodlands

Data from a long-term study (1993–2003) using artificial nest-boxes, were analysed to examine competition for nesting between blue tit Parus caeruleus and common dormouse Muscardinus avellanarius in Sicily. Occupation rates and the reproductive biology of the blue tit in sample woodlots outside the distribution area of the common dormouse were used as a control in sample areas where the two species were syntopic. A selection test showed that the two species, when living in syntopy, actively chose the small nest-boxes, thus overlapping in the use of the same spatial resource. The experimental exclusion of the common dormouse from nest-boxes caused an increase of blue tit occupation rate. Once the effect of nest-box density was removed, complementary density changes between the two species clearly appeared. The population cycle of both species in the areas of syntopy showed a swinging pattern, i.e. in areas or during years of common dormouse high abundance few blue tits bred and vice versa. The abundance of the blue tit was affected not only by common dormouse abundance, but also by some habitat and climate variables. Blue tits had low breeding success and a high percentage of nest failure (38% in syntopy vs 3% in control areas), owing to nest destruction and predation by common dormouse, as well as probably also by other rodents (23%) and Martes martes (15%). Another experiment, using stuffed models, showed that the blue tit recognized the common dormouse as an enemy, and behaved as if confronted by a competitor or predator species to protect their nests.

Effects of nest and colony features on Lesser Kestrel ( Falco naumanni ) reproductive success

The Lesser Kestrel is a facultative colonial raptor mostly breeding in man-made structures. During 2009-2011 we checked the fate of 545 nests found in 18 colonies located in south-eastern Sicily. We determined the reproductive success of breeding pairs by analysing the survival time of each egg to hatching (n = 2,495) and each nestling to fledging (n = 1,849) with the linear hazard model of survival times. We determined whether egg and nestling survival differed between years with a Gehan–Wilcoxon test. By Cox regressions, we related the survival times with nest and colony features. Egg and nestling survival times showed a strong annual effect. The two reproductive stages of the Lesser Kestrel, when controlled for the annual effect, demonstrated a significant effect for some nest and colony features. Most of them, like the height from the ground, nest depth, reused nests and the presence of Jackdaws, are likely to be related to the predation pressure faced by Lesser Kestrel nests. Westward and southward nests had a better egg survival with respect to those on the cold sides and in the interior of buildings. The location of colony on the agricultural plain and human disturbance ranked as the most important variables, with core location of a colony and high disturbance levels negatively affecting the reproductive success of the Lesser Kestrel in the Gela Plain, so urging a more environmentally aware land use management of this Important Bird Area.

Mitochondrial simple sequence repeats and 12S-rRNA gene reveal two distinct lineages of Crocidura russula (Mammalia, Soricidae)

A short segment (135 bp) of the control region and a partial sequence (394 bp) of the 12S-rRNA gene in the mitochondrial DNA of Crocidura russula were analyzed in order to test a previous hypothesis regarding the presence of a gene flow disruption in northern Africa. This breakpoint would have separated northeast-African C. russula populations from the European (plus the northwest-African) populations. The analysis was carried out on specimens from Tunisia (C. r. cf agilis), Sardinia (C. r. ichnusae), and Pantelleria (C. r. cossyrensis), and on C. r. russula from Spain and Belgium. Two C. russula lineages were identified; they both shared R2 tandem repeated motifs of the same length (12 bp), but not the same primary structure. These simple sequence repeats were present in 12–23 copies in the right domain of the control region. Within the northeast-African populations, a polymorphism of repeat variants, not yet found in Europe, was recorded. A neighbor-join tree, which was built by sequences of the conserved 12S-rRNA gene, separated the two sister groups; it permitted us to date a divergence time of 0.5 Myr. Our data discriminated two different mitochondrial lineages in accordance with the previous morphological and karyological data. Ecoclimatic barriers formed during the Middle Pleistocene broke the range of ancestral species in the Eastern Algeria (Kabile Mountains), leading to two genetically separate and modern lineages. The northeast-African lineage can today be located in Tunisia, Pantelleria, and Sardinia. The northwest-African lineage (Morocco and West Algeria), reaching Spain by anthropogenic introduction, spread over north Europe in modern times. The Palaearctic C. russula species is monophyletic, but a taxonomical revision (ie, to provide a full species rank for the northeast taxa and to put in synonymy some insular taxa) is required.

Diurnal habitat suitability for a Mediterranean steppeland bird, identified by Ecological Niche Factor Analysis

Context. The negative effects of agricultural intensification and policies, use of pesticides, fertilisers and mechanised harvesting on several populations of pseudo-steppe birds have increasingly required more detailed and effective habitat suitability models. Distribution models of farmland species are prone to incur recordings of false absence data. Ecological Niche Factor Analysis (ENFA) allows identification of environmental predictors of species distribution by using presence data only. Aims. We quantified the diurnal habitat preferences and niche width of one steppe species, the stone curlew (Burhinus oedicnemus), with unfavourable conservations status in a Mediterranean area and reclassified a map with respect to habitat suitability classes according to the resulting distribution model. Methods. Ecological Niche Factor Analysis was used with GIS cartography customised with habitat and anthropogenic variables recorded during field surveys carried out in four study plots (~500ha) and at different spatial scales. Keyresults.Thestonecurlewselectedareaswithlowvegetationcover,suchas fieldsfollowingartichokeharvestingand tillage,closetoruralbuildingsandunpavedroads.Incontrast,thestonecurlewavoidedareaswithhighvegetationcoverand areas highlydisturbed byhuman-induced fires.Theoccurrenceof naturalvegetation wasneitherpreferred noravoided.The mostrobustmodelwasbasedonalarge-scaleanalysis(200mfromthebirdlocationpoints),accordingtowhichtheoptimal area for stone curlew distribution during its breeding season was restricted to 1% of the entire study area. Conclusions.Twouncorrelatedfactors,‘marginality’and‘tolerance’,describedthestonecurlew’snicheinthearea.The first index indicated selection for habitats that were marginal with respect to those available in the area, whereas the second indicatedaspecieswithamedium–wideenvironmentalniche.Inparticular,thestonecurlewoccupiedamuchmorerestricted niche(lowtolerance)inrelationtoindividualvariables.Theuseofcustomiseddatabasesatalargescaleofanalysiswasfound to more effectively reveal ecological requirements of this marginal and specialised species. Implications. Our results allowed us to indicate practical land management actions for the stone curlew, such as preventionofhuman-induced firesandincreaseofpastoralactivities.Ourresultsindicatedapotentiallypositiveroleoflittledisturbedserviceroadsalongruralbuildingsinstonecurlewdistribution,whichwarrantsfurtherresearch.Inaddition,studies are neededtoverify thepresenceof anecological trap inartichoke fields,theirpreferred habitat. As weshowedfor thestone curlew, niche analyses conducted at a large scale using customised databases could greatly improve habitat suitability models of farmland species.

Evidence of a highly complex phylogeographic structure on a specialist river bird species, the dipper (Cinclus cinclus).

This study details the phylogeographic pattern of the white-throated dipper (Cinclus cinclus), a Palearctic, temperate, passerine bird that is exclusively associated with flowing water. Our results reveal a complex phylogeographic structure with at least five distinct lineages for the Western Palearctic region. As for many species of the Western Palearctic fauna and flora, this genetic structure is probably linked to the isolation of populations in different southern refuges during glacial periods. Furthermore, the isolation of populations in Scandinavia and/or Eastern regions, but also in Morocco and probably in Corsica, was accentuated by ecological and biogeographic barriers during Quaternary interglacial periods. During glacial periods, Italy, Sicily and the Balkano-Carpathian region acted as major refuge zones for the dipper. At the end of the last ice age, Western Europe was repopulated by dippers from an Italian refuge, while Eastern Europe was recolonised by Balkano-Carpathian birds. A large contact zone between these two lineages was evidenced and extends from Luxembourg to Hungary. Finally, our results indicate the need to clarify the taxonomic status of the dipper, especially concerning the European subspecies whose validity appears uncertain.