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The reproductive output of wild bottlenose dolphins Tursiops truncatus has extensively been investigated; nevertheless, it remains widely unexplored in the Mediterranean Sea. We investigated the reproductive history of female bottlenose dolphins in the Aeolian Archipelago (Italy). Thirteen years of photo-identification data were used to track the reproductive pattern of 7 females and their 16 calves. The birth period was accurately estimated within 1 mo for 6 calves (37.5%), peaking in June/July. The mean number of calves for females was 2.3 ± 1.1 (SD), ranging from 1 to 4. The mean interbirth interval was 3.5 ± 1.6 yr, ranging from 2 to 7 yr. The mean weaning age was 3.2 ± 0.6 yr, although 1 calf may have been weaned as late as its fifth birthday. Mother-calf postweaning associations were tracked for 9 calves and ranged from 4 to 10 yr of residence in the maternal group of the calf. The age of first pregnancy was 7.5 yr. The number of calves was influenced by the mean maternal group size, with females that were sighted in larger groups having more calves. However, the number of calves was not influenced by the strength of the associations of mothers with other females. Calf mortality by age 1 was high (12.5%). Two juveniles also died postweaning within 6 yr of their birth. Finally, 2 females may have died during the study, as they were not re-sighted at the end of the study. Our results highlight the need to implement urgent conservation actions to protect this bottlenose dolphin population.

Understanding large carnivores' behavioural adaptations to habitat modifications is critical for their persistence in human‐modified environments. Based on 10 Global Positioning System‐collared wolves in a protected area of central Italy, we investigated wolf responses to anthropogenic features such as roads and settlements by using Step and Resource Selection Functions. We revealed that responses by wolves to anthropogenic features varied according to behavioural state (travelling vs. resting) and social affiliation (pack members vs. floaters), while accounting for seasonal and circadian effects. During summer, pack members strongly avoided roads and settlements throughout all day, both when travelling and resting, and complemented this response by selecting forested areas and shrublands. Conversely, during fall and winter, pack members relaxed the avoidance towards anthropogenic features by travelling closer to main roads and settlements, but they still selected resting sites farther from anthropogenic features and located them in denser cover and along steeper slopes. Compared to pack members, floaters, when travelling, showed a weaker avoidance of main roads and settlements and did not show any selection pattern towards environmental variables. When resting, contrary to pack members, floaters selected sites closer to main roads and settlements, even though these were still located along denser cover and steeper slopes. Our findings suggest that wolves living in human‐modified landscapes adapt behaviourally to the spatial and temporal distribution of perceived interference by humans and that their response is complementary to the expected seasonal and circadian variation in human activity. These adaptations appear to be aided by the selection of habitat features that enhance security and allow segregation from humans. Maintenance of such habitat characteristics appears of critical importance to ensure the functionality of behavioural adaptations by wolves living in human‐modified landscapes. [ABSTRACT FROM AUTHOR]

Large carnivores are amongst the most susceptible species to human activities, and human-modified environments pose a threat to carnivore conservation. Wolves (Canis lupus Linnaeus, 1758) in the central Apennines, Italy, have coexisted with humans since historic times and represent a good case study to assess their spatiotemporal response to anthropogenic factors. From 2008 to 2010, we investigated the spatial behavior of wolves (seven wolves in five packs and six floaters) in the Abruzzo Lazio and Molise National Park. Orographically corrected annual home ranges of resident wolf packs, estimated through the Brownian bridge movement model, averaged 104 ± 24 km2 (mean ± SD), whereas floaters used two- to fourfold larger areas (293.8–408.7 km2). We did not detect any seasonal effect on home range size, but home ranges were larger during the night and in areas of greater road density, especially during summer. By estimating core areas through an individual-based approach, we also revealed a habitat-mediated response to human presence and activity, as resident wolves preferentially established core areas at greater elevation and in the more forested and inaccessible portions of the home range. [ABSTRACT FROM AUTHOR]

Detection of non-target species during distribution surveys may influence the detection of the focal species, due to bait being consumed, or trapping devices inactivated. The aim of this work was to evaluate the effect of non-target species (field mice, Apodemus sp.) on the detection and occupancy estimates of a target species (the red squirrel, Sciurus vulgaris) during hair-tubes surveys. Following a modelling approach that accounted for imperfect detection of both target and non-target species, we tested the hypothesis that detection probability of the red squirrel is affected by detection of field mice. We also investigated the level of bias that occurred in estimation of key-parameters such as probability of presence and detection probability. Our results show that detection of red squirrels and field mice using hair-tubes surveys is not independent. Detection probability of the red squirrel was higher when field mice did not visit the hair-tubes. Nevertheless, there was no bias in parameter estimates, therefore relatively accurate estimates would have been obtained despite this interference. [ABSTRACT FROM AUTHOR]

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The article cites a research study conducted to analyze how the habitat and season impacts grouping of forest buffalo resting places. It is reported that because of the shy nature and limited distribution of forest buffalo, the only forest-dwelling subspecies of the African buffalo, current knowledge on the ecology and behavior of it is very limited. According to available data, it is associated with open habitats where it gets its main food resources. The forest buffalo lives in smaller groups in contrast to the savannah buffalo. Researchers investigated whether buffaloes were packed more tightly in open habitat than in closed habitat while resting.

Hair tubes are often used to monitor red squirrel in fragmented landscapes, where presence/absence data are gathered to determine its distribution and factors affecting it. Despite many applications and evaluation of this technique for density estimation, the reliability of absence data has been overlooked, as no rigorous statistical estimate has been attempted both on the survey duration and on the reliability of absences. Accurate determination of the duration of a survey (e.g. how many visits should be carried out to consider the species absent rather than non-detected) will affect total costs and number of monitored sites; moreover, false absences will bias the distribution estimates. By applying some recently developed occupancy models, we estimated detection probability and sampling size required to infer red squirrel absence. Application of this sampling and data analysis protocol allows to infer the species absence at a reasonable cost and thus to evaluate the reliability of a presence/absence dataset. [ABSTRACT FROM AUTHOR]

Myotis capaccinii is one of the most endangered Mediterranean bats. We radio tracked 21 adult individuals to assess foraging range and analyse micro-habitat selection around a nursery roost in central Italy. Habitats were characterized by development of riparian vegetation, distance between banks, degree of water clutter and levels of water pollution (expressed by macro-benthic bioindicators). Diet was also analysed to see whether prey rarity might account for species decline. Myotis capaccinii proved highly mobile: the maximum straight line distance between roost location and the farthest foraging fix recorded on one night was c. 21 km, whereas this variable averaged 7.5 km for the entire study. In general, the species preferred calm waters bordered by well-developed riparian vegetation and large (>5 m) inter-bank distances. Such factors determined the overall quality of foraging sites. Although diet was dominated by pollution-tolerant insects such as Chironomus midges, bats preferred less polluted waters. Our study also confirmed the occurrence of piscivory in this bat. Of the factors potentially responsible for species endangerment, the most likely are general habitat degradation, that is alteration of riparian vegetation and pollution, and cave roost loss. Given the large ecological niche overlap, increasing Myotis daubentonii may be outcompeting M. capaccinii. The most urgent actions to preserve M. capaccinii are extensive restoration of riparian vegetation and strict roost protection. Our study offers indications about where, and how, restoration of riparian vegetation may translate into best conservation results. [ABSTRACT FROM AUTHOR]

Making an inference on the absence of a species in a site is often problematic, due to detection probability being, in most cases, <1. Inference is more complicated if detection probability, together with distribution patterns, vary during the year, since the possibility of inferring a species absence, at reasonable costs, may be possible only in certain periods. Our aim here is to show how such challenging situations can be by tackled by applying some recently developed occupancy models combined with sample size (number of repeated surveys) estimation. We thus analysed the distribution of two rodents Myodes glareolus and Mus musculus domesticus in a fragmented landscape in central Italy pointing out how it is possible to identify true absences, non-detections, extinctions/colonizations and determine seasonal values of detection probability. [ABSTRACT FROM AUTHOR]

The forest buffalo Syncerus caffer nanus is one of the three subspecies of African buffalo inhabiting the rainforests of Western and Central Africa. Because of its secretive behaviour and main habitat (dense rainforests), there is little quantitative information on the habitat preferences of this buffalo. We present here the first data on the frequencies of this species along a habitat gradient ranging from clearings and rivers to forests, as well as the characteristics of the buffalo's resting places. We recorded information from a buffalo herd during the period January 2002–January 2004 in the Bai-Hokou area (Dzanga-Ndoki National Park, Central African Republic). Resting places were firstly compared with available habitat (i.e. resting vs. random sites) and, successively, comparisons were made between diurnal versus nocturnal and wet versus dry season resting places. Forest buffalos were found to be highly dependent on clearings, as well as on the more open forest stands, characterized by large trees and open canopy. Such preferences could be due to the tendency of the buffalos to rest all together; open patches are likely to facilitate social interactions between the members of the herd. [ABSTRACT FROM AUTHOR]

The existence of allometric relationships between home-range size and body mass was tested for 34 Italian mammals and 106 Italian birds. These allometries were investigated in relation to a carnivorous, omnivorous or herbivorous diet and, in the case of birds, also territoriality. Initially, non-phylogenetic comparative analyses were undertaken by fitting general linear models to data on average home-range size and average body mass obtained from the literature. Then, two phylogenetic trees for the studied species of mammals and birds were reconstructed and phylogenetic independent contrasts were applied in order to determine the influence of phylogeny on these relationships. For mammals, the type of diet proved to be a determining factor in defining the relationship between home-range size and body mass. Significant allometries were found with both conventional and phylogenetic analyses in all trophic groups. The results emphasized the importance of the spatial distribution of resources in understanding these allometries. For birds, conventional analysis showed significant relationships between home-range size and body mass, and pointed to the importance of both diet and territorial systems in understanding these allometries. After controlling for phylogeny, significant allometries were found only for those birds for which information on the size of their feeding territory was available. Regardless of the complexity of factors influencing the home-range size of a species, the outcomes of this study support the notion of the existence of an allometry between home-range size and body mass among Italian mammals and birds, suggesting that further developments of this area of investigation may prove worthwhile. [ABSTRACT FROM AUTHOR]

An investigation is reported on the use of and preference for riparian vegetation, road verges, ponds and farms by polecats Mustela putorius L. living in a fragmented cultivated area. Eighteen polecats of both sexes were marked with radio-collars and monitored for 2–18 months each. Individuals were monitored with single nightly radio-locations, and during 12- and 24-h continuous sessions. Sex and seasonal variations in the density of key habitat features within home ranges were analysed. In order to measure the seasonal strength of attraction to key habitat features, the average distance to these features of observed trajectories, and of corresponding Monte-Carlo simulations, was compared. Polecats positively selected riparian vegetation within their home range throughout the year. Female home ranges contained more farms and ponds than those of adult males in the breeding season. Males expanded their home ranges in the breeding season, and the strength of attraction to riparian vegetation and ponds increased accordingly. The remnants of riparian vegetation apparently acted as a key habitat feature providing food and cover. Furthermore, these linear and interconnected landscape elements can facilitate the long-range movements involved in the search for mates. [ABSTRACT FROM AUTHOR]

We investigated key habitat features used by beech martens occupying a fragmented agricultural landscape. Locations of eight martens were radio-monitored daily for 4–12 months each. We evaluated the selection of home ranges within a geographic area, as well as the selection of habitat features within home ranges, using random simulations for comparison. Home ranges included more wood and scrub vegetation, and less arable land, than random simulations. They also included a higher proportion of watercourses with continuous vegetation along their verges, and were closer to these watercourses than random simulations. Within home ranges, beech martens used wood and scrub vegetation, and farm buildings, more intensively than expected, and arable land less than expected. On average, beech martens stayed close to watercourses (where most of the wood vegetation occurred) but not to farm buildings, indicating that only the former shaped beech marten movements. By these findings, arable land appeared to act as a seldom traversed barrier, making farm buildings uneasy to reach if they are located far from watercourses. [ABSTRACT FROM AUTHOR]

Abstract We used noninvasive methods to obtain genetic and demographic data on the wolf packs (Canis lupus ), which are now recolonizing the Alps, a century after their eradication. DNA samples, extracted from presumed wolf scats collected in the western Italian Alps (Piemonte), were genotyped to determine species and sex by sequencing parts of the mitochondrial DNA (mtDNA) control-region and ZFX/ZFY genes. Individual genotypes were identified by multilocus microsatellite analyses using a multiple tubes polymerase chain reaction (PCR). The performance of the laboratory protocols was affected by the age of samples. The quality of excremental DNA extracts was higher in samples freshly collected on snow in winter than in samples that were older or collected during summer. Preliminary mtDNA screening of all samples allowed species identification and was a good predictor of further PCR performances. Wolf, and not prey, DNA targets were preferentially amplified. Allelic dropout occurred more frequently than false alleles, but the probability of false homozygote determinations was always < 0.001. A panel of six to nine microsatellites would allow identification of individual wolf genotypes, also whether related, with a probability of identity of < 0.015. Genealogical relationships among individuals could be determined reliably if the number of candidate parents was 6–8, and most of them had been sampled and correctly genotyped. Genetic data indicate that colonizing Alpine wolves originate exclusively from the Italian source population and retain a high proportion of its genetic diversity. Spatial and temporal locations of individual genotypes, and kinship analyses, suggest that two distinct packs of closely related wolves, plus some unrelated individuals, ranged in the study areas. This is in agreement with field observations. [ABSTRACT FROM AUTHOR]

During the breeding season female elephant seals spent most of their time on land inside harems. When they arrive on land before joining harems, and when they leave harems to return to sea, they are exposed to secondary males and may suffer intense harassment. Hence, arrival and departure present an ideal opportunity to test hypotheses concerning female tactics of harassment reduction. We studied harassment during arrival and departure in two southern elephant seal populations at Punta Delgada (Valdés Peninsula; DEL hereafter) and Sea Lion Island (Falkland Islands; SLI hereafter). Females were less likely to be intercepted by males during arrival than during departure. They also arrived mostly at high tide, thereby reducing the distance from water to the harems. Interception rate and harassment during departure were higher at DEL, where male density and the breeding sex ratio affected the likelihood of interception; on SLI, the socionomy had a small effect. Harassment was higher at low tide at DEL but not at SLI, because tide level variation was larger at DEL and this resulted in a larger variation in the distances of the harems from the water. Females departed more often than expected at high tide at DEL but not at SLI. In both populations females departed directly to sea, rarely stopping before reaching the water, and they never sought contact with males. Social distraction during departure significantly reduced the likelihood of interception. Departures were more frequent during periods of high social activity, and females departing just after other females were less prone to harassment. Accepting copulations with secondary males may reduce the dangerous effects of harassment: interactions occurring during departure were less frequently protested, but we found no indication that departing females were facilitating copulations in a special manner. Quantity and quality of protest during departures was similar to protest during the last days of residence of the females in the harem. [ABSTRACT FROM PUBLISHER]

Female southern elephant seals are expected to adopt behaviours that reduce the costs of male harassment. We studied the strategies and tactics of harassment reduction in two populations, at Punta Delgada (Valdés Peninsula, Argentina) and at Sea Lion Island (Falkland Islands) during five breeding seasons in all. Females synchronized their breeding activities to reduce harassment risk, and rarely bred alone to reduce the likelihood of encounters with subadult males. Females showed a clear preference for larger harems, that guaranteed a reduced harassment risk: movements between arrival on land and parturition were mostly from smaller to larger harems, and the likelihood of abandonment was lower for large harems. Females protested against approaching males in the vast majority of interactions, regardless of the social context and the status of the interacting male, but protest varied with female breeding status and male phenotype. Frequency of protest of individual females decreased linearly from the beginning of oestrus to departure to sea. Interactions with mature males were less protested. The frequency of protest linearly decreased with increase in age class, and mating attempts by males of higher status and dominance rank were less often protested. Most of this variation with male phenotype, however, was due to the higher probability of older and more dominant males to interact with oestrus females that had an intrinsicly lower tendency to protest. Protest variation in relation to male phenotype was more parsimoniously explained as a consequence of differential access of males to oestrus females rather than of female selectivity. Protests had a role in disruption of mating attempts, although the phenotype of interactors was more important: adult, large and dominant males disrupted interactions regardless of incitation by female protest. [ABSTRACT FROM PUBLISHER]

Notwithstanding the important role of male harassment of females for theories of the evolution of mating systems, accurate estimates of its frequency and costs are available for only a few species. In this paper, we quantify the frequency of harassment in southern elephant seals, compare occurrences of harassment inside and outside harems, and estimate the costs of harassment in two populations at Sea Lion Island (Falkland Islands) and Punta Delgada (Valdés Peninsula). Southern elephant seal males are much larger than females, have enlarged canines, and are much more agile on land; hence, females have a small probability of escape from approaching males and may suffer intense molestation. Most males had limited access to females due to the despotic mating system, and their libido was high. Females were approached by males at high frequency, mostly when out of oestrus. The harassment level was negatively related to the ratio of breeding females to breeding males, and females breeding at the peak of the season suffered a lower level of harassment. Females of large harems were harassed less, and their likelihood of interact with secondary males was lower. The activity of harem females was less disrupted, and females in large harems had a higher proportion of resting time. Isolated females suffered more herding episodes, and were approached more frequently by secondary males. The main short-term cost of harassment was disruption of the females' activity schedule; harassment level and total active time were positively related. Suckling bouts were rarely interrupted by male harassment. Mother and pup separations caused by males interaction were rare, short-lasting, and rarely permanent. There was little effect of harassment on weanling weight, physical damage of females was rare, and there was only a slight non-significant negative relationship between harassment level during one season and the likelihood of surviving to the next. [ABSTRACT FROM PUBLISHER]

In this paper we compare some socio-ecological traits of feral dogs and wolves in order to assess the social ecology of feral dogs in terms of its adaptive value in the natural environment, and to evaluate to what extent the domestication process altered the wolf's socio-ecological patterns. Referring to feral dogs as those dogs living in a wild state with no food and shelter intentionally provided by humans, and showing a continuous and strong avoidance of direct human contacts, we review the currently available information on feral dog ecology, and particular reference is made to a 3-year term project on feral dog ecology in Abruzzo, Italy. Through comparison of relevant behavioural and ecological features of both wolves and feral dogs, we hypothesize that some aspects of the feral dogs' ecology, having escaped natural selection pressures, represent primarily expression of “evolutionary inertia” or an epiphenomena of artificial selection. Fitness-related measures of sociality, demography, reproduction, space-use, activity patterns, and feeding ecology in feral dogs tend to support our original hypothesis: feral dogs are not reproductively self-sustaining, suffer from high rates of juvenile mortality, depend indirectly upon humans for food, co-optable individuals, and space, and their demography appears dominated by unpredictable mechanisms. However, further research is needed, especially concerning different ecological conditions and multi-generational time-scales, as well as the role that dominant breed-types and cross-breeding history within feral dog groups might play in the expression of the analyzed socio-ecological features. [ABSTRACT FROM PUBLISHER]