Planning conservation actions by investigating nest preferences and biotic and abiotic factors within lesser kestrel (Falco naumanni) colonies

The lesser kestrel (Falco naumanni) was until recently classified as a Vulnerable species. It is a cavity nester species finding proper nest sites in natural cliff holes or, as more frequently today, cavities found within rural buildings. These are often abandoned and therefore, with no maintenance, the main structures of kestrel colonies have been collapsing across years. To counterbalance the reduced availability of nesting sites for kestrels, and because of their unfavorable conservation status, artificial nest boxes have been placed in several areas of their breeding range. On our study site, the Gela Plain in Sicily, as on other Mediterranean breeding areas, high temperatures may reach lethal values for the nest content. Since 2004, we collected biotic and abiotic data at macro- and micro-scales to integrate an analysis aiming to predict nest temperatures in different nest types. Paradoxically, early breeders preferentially occupied the coolest nest types, the roof tiles, whereas late breeders, starting their nesting attempts with hotter temperatures, occupied the overheated nest boxes. We discuss our findings in the light of planning proper and efficient conservation actions, such as providing different nest types, by pondering whether kestrel nest preferences might either sort into ecological traps or be the result of ecological limitations

Changes in eggshell ultrastructure of Falco naumanni and Tyto alba exposed to pesticides and polychlorinated biphenyls (PCBs)

Changes in the quality of eggs of birds exposed to environmental contaminants have been described, but few reports concern eggshell ultrastructure. In this study, infertile or addled Lesser Kestrels (Falco naumanni) and Barn owls (Tyto alba) eggs were collected from the polluted area of Gela plain (Sicily) during 2007, and compared in terms of organophosphate and organochlorine pesticides, and PCBs levels, and eggshell ultrastructure as determined by scanning electron microscopy. Pesticide and PCB residues in eggs were determined by Gas chromatography/ mass spectrometry (GC/MS) [GC Agilent 7890A/MS Agilent 5975C (Agilent technologies) using a DB-5 capillary column in the selected ion monitoring mode]. The GC/MS analysis revealed that eggs contained measurable amounts of some pesticides and PCBs. There was a low detection of organophosphate pesticides while the most abundant organochlorine residues detected were p,p’ DDT, p,p’ DDE, and Hexachlorobenzene. While, the most abundant PCBs detected congeners were PCB 138, 153, 170, 180, and 187. Although the general structure of the eggshell layers was maintained, the results showed ultrastructural differences in mammillary and palisade eggshell layers between high level and low level contaminated eggs in Tyto alba. Furthermore, mammillary cores of the eggshell had an increased distance between themselves with respect to well organized structures present in uncontaminated egg. In this paper we verify the presence of environmental contaminants in the eggs and document structural changes in bird of prey eggshells. The data could suggest that some contaminants can contribute to reduced reproductive performance (infertile or addled egg) by structural changes in the eggshell. The alteration in morphological disposition of mammillary cores could also suggest an impairment of gas exchange

Living on the Edge: Assessing the Extinction Risk of Critically Endangered Bonelli’s Eagle in Italy

Background: The population of Bonelli’s eagle (Aquila fasciata) has declined drastically throughout its European range due to habitat degradation and unnatural elevated mortality. There are less than 1500 breeding pairs accounted for in Europe, and the species is currently catalogued as Critically Endangered in Italy, where the 22 territories of Sicily, represent nearly 95% of the entire Italian population. However, despite national and European conservation concerns, the species currently lacks a specific conservation plan, and no previous attempts to estimate the risk of extinction have been made. Methodology/Principal Findings: We incorporated the most updated demographic information available to assess the extinction risk of endangered Bonelli’s eagle in Italy through a Population Viability Analysis. Using perturbation analyses (sensitivity and elasticity), and a combination of demographic data obtained from an assortment of independent methods, we evaluated which demographic parameters have more influence on the population’s fate. We also simulated different scenarios to explore the effects of possible management actions. Our results showed that under the current conditions, Bonelli’s eagle is expected to become extinct in Italy in less than 50 years. Stand-alone juvenile mortality was the most critical demographic parameter with the strongest influence on population persistence with respect to other demographic parameters. Measures aimed at either decreasing juvenile mortality, adult mortality or decreasing both juvenile and adult mortality resulted in equivalent net positive effects on population persistence (population growth rate l.1). In contrast, changes aimed at increasing breeding success had limited positive effects on demographic trends. Conclusions/Significance: Our PVA provides essential information to direct the decision-making process and exposes gaps in our previous knowledge. To ensure the long-term persistence of the species in Italy, measures are urgently needed to decrease both adult mortality due to poaching and juvenile mortality due to nest plundering, the top ranking mortality causes.PLL is supported by a “Juan de la Cierva” postdoctoral grant of the Spanish Ministry of Economy and Competitiveness (reference JCI-2011–09588)

Microevolution in the sicilian shrew crocidura sicula (mammalia, soricidae) tested by rapd-pcr fingerprinting

Genetic variation in samples of the endemic Crocidura sicula living in Sicily and in two surrounding small islands, Marettimo and Ustica, was analysed by Random Amplified Polymorphic DNA fingerprinting (RAPD) and compared to morphometrics and external phenotypes. Molecular variation in the random sample of 99 DNA fragments of the Ustica shrews, showing.a melanic fur and a size-shape variation in skull morphometrics, is of comparable size to that of the of northwestern and northeastern samples Sicily (Tufanio and Madonie). In the Marettimo shrews, bicoloured (grey and white) animals like those coming from Sicily and presenting a significant reduction in body-size and skull morphometrics, molecular differentiation is higher than in those of the other locations, and characterizes this geographic population. Considering the paleogeographic records, it is hypothesized that the Marettimo shrews must have been isolated longer from the mother-island; whereas for the Ustica shrews, a more recent arrival/isolations presumed. The RAPD results proved to be consistent with this reconstruction of the C. sicula biogeography. The Marettimo population, as opposed to that of Ustica, can thus be considered ‘one step further’ on the road of the speciation process. Melanism in the more recently isolated Ustica population does not parallel genetic differentiation and could emerge as an answer to the very strong selection and ecological adaptation in that volcanic insular environment. In any case, each population living in these two small islands off Sicily shows an independent evolutive divergence. © 1997 Taylor & Francis Group, LLC

Grid-trapping of the wood mouse (<em>Apodemus sylvaticus</em>) in a mediterranean oak-wood (Sicily) / Analisi del popolamento di topo selvatico (<em>Apodemus sylvaticus</em>) in un querceto mediterraneo (Sicilia)

<strong>Abstract</strong> A grid-trapping (CMR Method) of the Wood Mouse (<em>A. sylvaticus</em>) resident population was carried on three sample areas in a Mediterranean Oak-wood (Bosco della Ficuzza, Palermo). Fifty live traps were settled on a 0.5 ha grid at each sample area and permitted to calculate the Petersen-Lincoln Index (modified by Chapman). The relative density in the typical oak-wooded area (20.4/ha) is highest than in the ecotonal and gazed sample area (12.6/ha). Analysis of ground permanence shows that the population in the wooded area is more dinamic than in the other area; in the former area a large number of new captures occurs, in fact, each month and the monthly variation of the relative density has a different trend. These results would confirm the indirect data coming from pellets analysis showing how in Sicily the highest densities occur in woodlands (oak-woods, as well as beech forests). The ecological niche of the Wood Mouse, due also to the apparent lack of <em>A. flavicollis</em>, is thus larger than in peninsular Italy and continental Europe. The reproductive season lasts over the whole year but the birth peaks occurred in summer (1988) and late fall (1989). Population each year stabilizes for overwintering and later (Jun-Nov) is almost completely renowed. Moreover, differences in sex and age trappability in relation to the two mode1 of traps utilized and a low mortality due to the cautions in handling the trapped mice, were recorded. <strong>Riassunto</strong> Allo scopo di evidenziare le differenze tra i popolamenti di <em>Apodemus sylvaticus</em> (Linnaeus, 1758) in relazione all'habitat, sono state effettuate in una tipica querceta mediterranea (Bosco della Ficuzza, PA) griglie di trappolamento in tre aree campione, ciascuna con differenti caratteristiche ambientali e morfologiche. Il campionamento, che si è protratto per circa due anni, è stato condotto con il metodo CMR (cattura-marcaggio-ricattura). I risultati ottenuti indicherebbero che in Sicilia la nicchia ecologica del Topo selvatico risulta più ampia che nel resto d'Italia, grazie anche alla apparente assenza di <em>A. flavicollis</em>. Nell'area boschiva, in cui si raggiunge una maggiore densità di popolazione, si evidenzia una popolazione in continuo ricambio e con un andamento diverso; mentre nell'area ecotonale si rinviene una popolazione con densità minore ma più stabile e costante nel tempo. Sono stati inoltre evidenziati i seguenti fattori: differenze nella probabilità di cattura fra sessi ed età in relazione al tipo di trappola: bassi valori di mortalità nelle tre aree in relazione alle precauzioni prese; maggiore stabilità delle popolazioni studiate durante il periodo novembre-maggio; estensione del periodo riproduttivo

Distribution and ecology of Dormice (Myoxidae) in Sicily: a preliminary account

<strong>Abstract</strong> Three dormouse species are recorded in Sicily: <em>Myoxus glis</em>, <em>Muscardinus avellanarius</em> and <em>Eliomys quercinus</em>. Their distribution is mapped according to the 10 x 10 km squares of the UTM grid. Data were collected until May 1993, mostly coming from pellet analysis, and direct records (vocalization listening, museum specimens, field observations, literature, etc.). The Fat dormouse (5.3% of 10 x 10 km squares) and the Hazel dormouse (2.1%) are mainly localized within deciduous wooded areas like the beech forests and the hazel groves mixed with oaks and chestnuts of Nebrodi and Madonie. The Fat dormouse is also present in south-eastern Sicily (Monti Iblei) and on in Eolian island (Salina). The Garden dormouse shows the widest distribution (21.2%), ranging from sea level to the beech forests (1600 m a.s.1.). Dormice are rarely preyed upon by Owls in Sicily, generally forming less than 1.5% of the total prey, with the exception the Fat dormouse (5.3%). Other occasional predators, so far recorded, are the Red Fox (<em>Vulpes vulpes</em>) and the Lanner (<em>Falco biarmicus</em>). Hibernation regularly occurs at high altitudes, but seems to be absent or curtailed in the warm habitats below 500 m a.s.1. <strong>Riassunto</strong> <strong>Distribuzione ed ecologia dei Mioxidi in Sicilia: dati preliminari</strong> - Tre specie di Mioxidi vivono in Sicilia (<em>Myoxus glis</em>, <em>Muscardinus avellanarius</em>, <em>Eliomys quercinus</em>). Storicamente (1850) essi erano presenti nelle principali aree boscate (Nebrodi, Madonie, Etna), solo nella metà di questo secolo, il Ghiro ed il Quercino furono scoperti alle isole Eolie (Salina e Lipari). Si riporta la carta di distribuzione di ogni specie (griglia UTM, 100 kmq) ricavata dall'analisi della dieta di predatori, osservazioni dirette, trappolamenti ed esemplari citati in bibliografia o conservati nei musei. Il Ghiro (5,3%) ed il Moscardino (2,1%) sono localizzati nei boschi decidui di querce e faggio e, più in basso di noccioli, querce e castagni dei Nebrodi, Peloritani e Madonie. Il Ghiro è presente anche sull'Etna ed in un'area meridionale della Sicilia (Iblei). Il Quercino mostra la distribuzione più ampia (21,2%) ed è presente in una gran varietà di habitat dal livello del mare fino alle faggete delle Madonie. I Mioxidi in Sicilia risultano predati finora occasionalmente dalla Volpe e dal Lanario e raramente dal Barbagianni e dall'Allocco. Solo il Ghiro risulta predato regolarmente (5%) dall'Allocco e risulta la preda più importante in termini di biomassa (47%) nei boschi dell'Etna e dei Nebrodi. Il periodo di letargo, desunto da osservazioni dirette e dalle borre, sembrerebbe normale (autunno inoltrato-primavera) alle alte quote e assente o molto ridotto e discontinuo sotto i 400 m

<em>Crocidura</em> populations (Mammalia, Soricidae) from the Sicilian-Maltese insular area

<strong>Abstract</strong> Recent studies have shown the presence of a new endemic species of Soricidae, <em>Crocidura sicula</em>, in the Mediterranean area. Its karyotype consists of 36 chromosomes (NF = 56, NFa = 52) as previously recorded in specimens from Sicily and Gozo (Malta). Karyological analysis carried out in the present study on specimens from Marettimo (Egadi) and Ustica and on two additional Sicilian localities proved the presence of the same <em>C. sicula</em> karyotype. The multivariate analysis of skull and mandible of these populations revealed a pattern of geographic variation which is mainly related to a size decrease (76% of the total variability accounted for) in shrews living in the small islands around Sicily. The body biometrics of these insular shrews follows this trend, with some exceptions such as in Ustica, where shrews are relatively bigger. The shrews from Ustica show also melanic fur, which is darker than the grey-witheish colour found in conspecific populations. Such a phenotype could be the result of adaptation to the volcanic environment on this island. This latter population is, of all the small islands, the most divergent and differentiated from the mother-island; if considering its skull morphometrics (i.e. the residual 24% of total variability) and its body biometrics

Asymmetrical interspecific communication in avian mixed species colonies

Sympatric species derive benefits by attending to information conveyed by heterospecifics. We previously reported reduced vigilance among jackdaws (Corvus monedula) and lesser kestrels (Falco numanni) residing in mixed species colonies and conducted the present study to test for interspecific communication of threat associated with European magpies (Pica pica) as nest predators. After quantifying structural differences in jackdaw and lesser kestrel calls relative to European magpie versus non-predator models, we played back calls of jackdaws and lesser kestrels representative of the different model types to test whether receivers perceive threat-related variation in either conspecific or heterospecific calls. We detected differential behavioural responses to call playbacks, with both jackdaws and lesser kestrels increasing vigilance and alarm calling in response to magpie elicited jackdaw calls, but not to other call types. Taken together, our results suggest that jackdaw, but not lesser kestrel vocalizations, communicate enhanced threat associated with European magpies as possible nest predators. This interspecific alarm communication benefits both jackdaws and lesser kestrels, and at least in part, explains asymmetric responses of jackdaws and lesser kestrels to magpies attending mixed species colonies in nature