75 research outputs found
Abundance of Rock Partridge (Alectoris graeca) in relation to the multi spatial structure of habitat and food availability.
In the Prealpi Giulie Natural Park the distribution and abundance of the Rock Partridge Alectoris graeca saxatilis have been studied in 5 sample areas using the play-back technique, and related to habitat availability (Vegetation Map of the park, 1:25.000) at different spatial scales. The UTM 1x1 kilometer regional grid has been used for a large scale approach, assigning the number of partridges counted to each quadrant. The mean geo-morphological aspects, the herbaceous and shrub vegetation characteristics (density, height, colour, etc), the abundance of insects (pitfall traps), and management applied on the area (pasture, mowing, etc) have also been measured for each quadrant. Buffer surfaces of 500 and 100 meters of radius from the detection-points of the animals have been used respectively as medium and small scale approaches and compared to randomly selected buffer areas. GIS analysis has been carried out to determine habitat coverage in each quadrant and buffer. Different parameters seem to describe properly the ecological requirements of this species in the study area. Its abundance was correlated at all scales to grasslands widely colonized by Genista radiata. This element, together with high herbaceous vegetation at large scales, could provide shelter from flying predators. At medium to small scales species-rich mesophile hay meadows seem to enhance the presence of Rock Partridges, locally providing a large stock of food resources and together with xeric grasslands representing the optimal mixture of habitats for this phasianid. In contrast pastures colonized by shrubs and trees (high density, large diameter) seem to have a negative effect on the species presence at large to small scales. This multiscale approach allows to detect more appropriately the ecological requirements of this animal
The Return of Large Carnivores and Extensive Farming Systems: A Review of Stakeholders' Perception at an {EU} Level
Conflicts between large carnivores and human activities undermine both the maintenance of livestock practices as well as the conservation of carnivores across Europe. Because large carnivore management is driven by a common EU policy, the purpose of this research was to assess stakeholders\u2019 perception towards bears and wolves at an EU level. We conducted a systematic search and subsequent analysis of 40 peer-reviewed studies collected from 1990 to September 2020 within Member States of the EU. Rural inhabitants and hunters exhibited the most negative attitude compared to urban inhabitants and conservationists, whose attitude was more positive. We showed that direct experience with predators as a consequence of ongoing re-colonization may have affected the degree of acceptance of certain categories and that the long-term coexistence between humans and carnivores does not necessarily imply increased tolerance. To encourage coexistence, we recommend monitoring changes in attitudes over time relative to carnivore population dynamics
The energetic values of landscape components as a tool to describe the behavior of the brown bear (Ursus arctos L.) in relation to the ecological requirements
The aim of research was to study the brown bear presence in relation to the landscape pattern, expressed in terms of energy flows, through the quantification of the energetic values and meaning of the natural (biotic and a biotic) and human-related (road networks, settlements, etc.) landscape components. These values were correlated to the estimation of the energy requirements of the bears monitored with GPS techniques (n=4, males) and to the their presence and behavior. The spatial model of energetic values for landscape components have been developed by GIS technology and in the respect to the ecological requirements of brown bear in the central and north east alps (North of Italy, Slovenja and Austria). Data sources were public databases as Corine Land Cover project (UE), Carta della Natura Project (ISPRA) Digital Terrain Model. The spatial resolutions utilized was 1km2 and the UTM grid was used. For each quadrant was calculated: habitat cover, geomorphology, human presence, brightness (solar radiation corrected for the tree cover) feeding allowance (food allowance index, IDA), climate (Modis), and energy values expressed as estimation of the potential cost of locomotion, thermoregulation, feeding , resting (output) and as potential energy of food allowance (input). For each animals tracked by telemetry were estimated the energy requirements in relation to the cost of basal metabolism,. thermoregulation, locomotion, feeding for each utilized quadrants and compared to the utilized quadrants and in the respect to different level of utilization. The identification and development of landscape indexes, describing many environmental components with implications on animal energy requirements, has been coupled with a behavioral pattern analysis and the computation of animal energy outcomes and incomes. The obtained thematic maps showed the spatial distribution of these input and output: thought them it is possible make habitat characterizations showing potential satisfaction level in terms of ecological requirements for the Brown bear and obtain useful information for defining the habitat energetic suitability at the trans regional scale. This study has revealed several emergent diurnal-nocturnal and seasonal energetic patterns in the use of landscape resources, and has allowed the implementation of some spatially explicit models for the estimation of energy inputs and outputs; the cost of thermoregulation and locomotion (output) and the potential allowance of energy (input), seems to influence the use of landscape and bear behavior. The future development of this research through the use of other individual location datasets (also belonging to different geographical contexts) may allow to refine the approach and identify more precisely the key spatial variables to be measured in terms of energy, as well as to apply this approach to more sophisticated models like IBMs (Individual Based Models)
Assessing the impact of bears, wolves and jackals on extensive livestock practices in north-eastern Italy
MANAGEMENT AND IMPLICATIONS OF A NEW PREDATOR SPECIES IN NORTH-EASTERN ITALY: THE GOLDEN JACKAL (CANIS AUREUS)
The golden jackal is a relatively new species in Italy, where it appeared about 30 years ago in the North-East. This study reports the first outcomes of acoustic monitoring of the species and the first warning of possible human-animal conflicts in Friuli-Venezia Giulia. We carried out 145 jackal-howling sessions in 5 macro-areas from summer 2011 to spring 2013, with an average of 5 emissions/session (679 emissions). We recorded 42 vocalizations, which were then analyzed in order to estimate the number of callers by screening the fundamental frequency of the single emissions within a howl. Jackal presence was confirmed only in 2 out of the 5 monitored macro-areas (Carnia and Carso), but it was stable only in Carso, with a 20% response rate. The response rate decreased with the number of emissions in a session (E1=9.6%, E2=7.1%, E3=8.0%, E4=3.2%, E5=2.5%, E6 and following=0.0%) and the responses were concentrated in February-April and July-August. Acoustic analysis of vocalizations allowed determining the number of emitters: one animal in 18 cases, two animals in 13 cases, three animals in 11 cases. These numbers are lower than those initially estimated during field recording sessions, when up to 5 individuals were supposed to vocalize simultaneously in one session. However, the presence of groups of up to 7 individuals has been recorded by scout cameras in Carso. In this area, three predation events, leading to the loss of 11 sheep, were reported by one farmer during the study period and are now becoming more frequent. In spite of this, the presence of a predator is well tolerated by this farmer, who valued this species as a touristic attraction for its importance as a source of biodiversity and landscape preservation. This situation suggests that, at the moment, the coexistence of the predator with farming activities may be possible, but a continuous monitoring of the species is required in order to prevent future problems. Jackal howling appeared to be an adequate technique for jackal monitoring. In order to optimize the efforts, our results suggest that sampling should be concentrated in few months, when response rate is higher, and limited to 3-4 emissions/session. Acoustic analysis of the recorded vocalizations is highly recommended in order to obtain more reliable information on the number of individuals. To this aim, keeping records of indirect signs of presence and the use of scout cameras may help to get a complete information on this expanding species
Stay home, stay safe? High habitat suitability and environmental connectivity increases road mortality in a colonizing mesocarnivore
Context Anthropogenic structures have considerable effects on ecosystems, disrupting natural population processes and representing a serious risk in terms of vehicle collisions. The golden jackal (Canis aureus) is a mesocarnivore species whose range is expanding in Europe. Roadkills are one of the main human-induced mortalities in Italy to the species.
Objectives Identify road-related characteristics and ecological factors related to golden jackal roadkill risk in Italy.
Methods We used habitat suitability (Maxent) and connectivity (Circuit theory) models to derive 15 metrics potentially affecting roadkill risk. We tested their influence using Bayesian generalized linear models and generalized linear models comparing golden jackal roadkill locations to random locations. Furthermore, we tested if there were significant sex, age-related and seasonal differences among roadkilled individuals.
Results We found that roadkill risk was higher in areas characterized by higher values of habitat suitability and connectivity, habitat fragmentation and along highways. It was lower with increasing distance to the source population and in the presence of guardrails. No significant differences were detected in terms of roadkill risk between sexes, age classes and season.
Conclusions The identified factors affecting road mortality of golden jackals in Italy provide insights on how to mitigate wildlife-vehicle collisions. Crossing areas, and visual and acoustic warnings for wildlife, as well as the importance of managing fences along high traffic volume roads could help mitigate further damage. Finally, there is a need to further investigate the effectiveness of mitigation measures in the light of the golden jackal’s ongoing expansion in a human-modified landscape
First telemetry data on golden jackal (Canis aureus) in Italy: insights on the species’ spatial ecology
Has the recolonization of the Po Plain begun? Updates regarding the presence of the Eurasian otter (Lutra lutra) in north-eastern Italy
Widespread in Italy in the early 1900s, the Eurasian otter subsequently underwent a dramatic decline that led to its local extinction in many administrative regions, with the exception of a small residual nucleus in southern Italy. For a few years now, the Austrian and Slovenian populations adjacent to north-eastern Italy have been increasing sharply, leading to a recolonization of the area by the species. During 2020, in Friuli Venezia Giulia, surveys of signs of presence were carried out in 48 grid cells (10 x 10 km) to update information on the species’ local distribution. The following monitoring methods were used: monitoring beneath bridges combined with transects along water courses. 17 grid cells tested positive for the presence of the species, and currently, the otter appears widely distributed in Friuli Venezia Giulia along the main waterways of the Eastern Alps and Prealps, and in some areas overlooking the plain of the Tagliamento and the transborder Isonzo-Soča basin, both included in the Po plain. These constitute the first observations of the species for more than 50 years. Compared to previous studies, 13 new grid cells involving the presence of otters were identified, including in lowland areas, suggesting a progressive expansion from the mountain ranges towards the Po-Venetian Plain. This represents, a spur to expand research and implement new studies to improve levels of knowledge about and the consequent protection of the species. Finally, the integration of transects along riverbanks to monitoring beneath bridges, allowed us both to collect numerous observation and to compare our results with previous studies
Relation between parasites, reproductive index and habitat change in Rock Partridge (Alectoris graeca) populations in the central Southern Alps.
Relation between parasites, reproductive index and habitat change in
Rock Partridge (Alectoris graeca) populations in the central southern
alps.
FABRO C.1, VISINTIN A.1, FILACORDA S.1, FRANGIPANE DI REGALBONO A.2, ARTUSO I.3
1Department of Agriculture and Environmental Sciences \u2013 University of Udine
2Department of Experimental Veterinary Science- University of Padua
3Comprensorio Alpino N\ub01 Val Brembana Hunting district
Within the hunting district of Val Brembana the presence of parasites along the intestinal tract
in 60 individuals (32 adults and 22 juveniles, 6 indeterminate) has been studied and correlated
to the reproductive indexes (R.I, measured on 3 and 6 years) of Rock Partridges Alectoris graeca
saxatilis in 6 different sectors and the habitat change. Within these sectors the coverage (%) of
several environmental classes in different sample areas has been identified through photo
interpretation over a time interval of 25 years. In the whole area a high spread of the nematode
Ascaridia was observed and high values of prevalence (P = 69.49%) and mean abundance (MA
= 15.21) have been found, while the presence of genus Capillaria was low with MA = 0.17 and P
= 13.56%. Heterakis was isolated in 33.90% of the Rock Partridges, with MA = 1.45. For Ascaridia
and Heterakis the relationship between variance and mean abundance (s2/MA) was
significantly greater than one (Ascarids = 48.94; Heterakis: 7.90) and the aggregation index k (s2
/ (s2-MA) ) was very close to zero, proving that these parasites show a highly aggregated
distribution within host populations. When analyzing separately the 2 age classes there
seemed to be no significant difference in parasitic infection susceptibility between juveniles (P
= 95.45%) and adults (P = 84.95%). Only MA and P of Heterakis in different sectors was
negatively correlated to a change in reproductive success, both in short and medium term,
while the sectors with the greatest MA of Ascaridia, both in short and medium term, showed
the highest mean reproductive rates and the sectors with the highest k of Capillaria had the
highest R.I. The presence of parasites and particularly the value of MA of Capillaria and the
average total number of parasites seemed to increase with the decreasing of open areas
(coverage) in the different sectors of the study area, as well as with the decreasing of this
observed coverage throughout the 25 year period. A negative correlation between open areas
and the s2/AM ratio was discovered to be very clear. The presence of open areas seemed to
affect significantly the abundance of parasites that in turn seemed to only partially drive R.I
changes. The research was supported by Comprensorio Alpino N\ub0 1 Val Brembana Hunting
district
Interreg NAT2CARE Project: Activation of Citizenship for Restoration and Conservation of N2K Cross-Border Areas Italy-Slovenia
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