1,721,219 research outputs found
Correlations between landscape features and crop type and the occurrence of the Ortolan Bunting Emberiza hortulana in farmlands of Central Italy
No full textThe occurrence ofOrtolan Bunting, a declining species in Europe,was investigated in relation to environmental characteristics of agricultural landscapes in Central Italy. The present work evaluated the significance of landscape features, land-use composition and
crop type at the 7-ha scale, in predicting the presence of the Ortolan Bunting. The presence of the species was not strongly linked with measures of habitat heterogeneity, but was related to certain crop types: sunflower, oats and alfalfa, and also to the availability of
bare soil. Patches of bare soilmay be characteristic for important foraging sites of the focal species. These results may help to predict Ortolan Bunting responses to changes in farming practices, and improve farmlandmanagement for themaintenance of the Ortolan
Bunting populations in Italy
Are the nesting probabilities of the red-backed shrike related to proximity to roads?
Full text linkVolume: 5Start Page: 1End Page: 1
SHRIKES LOVE THE ROADS IN AGRICULTURAL LANDSCAPES? Use of hierarchical partitioning to study the importance of proximity to the roads on the probability that Red-backed Shrike occupy suitable shrubs during breeding: preliminary results in farmlands of Central Italy
No full textRoads are a pervasive feature on the landscape and
their ecological effects on vertebrate wildlife have been
well documented. Indeed, the main types of effects
described have mainly negative consequences on
birds and other vertebrates. The major effects of roads
on birds include habitat fragmentation, traffic noise
and direct mortality from road kills. However, others
passerines like the Red-backed Shrike, Lanius collurio,
seem use the areas close to roads often for nesting and
hunting purposes. The aim of this work was to study
the importance of road proximity in the selection of
suitable shrubs for nesting by the Red-backed Shrike
in the farmlands of Central Italy. The study was conducted
in a breeding territory of the species in the River
Foglia catchment area in Central Italy. The bird data
were collected during the 2009 breeding season using
a complete mapping, in an area of 600 ha. Each shrub
was digitized and classified as “suitable” according to
previous studies on the ecology of the species in the
same region: vegetal species, size and density of foliage.
The suitable shrubs were classified as “occupied” or
“unoccupied” by a nest. Were also calculated the following
environmental parameters: altitude, nearest road
distance, shrub shape, shrub surface, shrubs density in
a fixed radius of 50 m, nearest shrub distance, landscape
fragmentation and land-use coverage. The relationships
between nesting and environmental parameters were
examined using a GLM stepwise backward procedure
to select the most significant variables using the AIC
criterion. In order to quantifying the effects of every
independent variable (in particular “nearest road distance”)
was used the hierarchical partitioning protocol,
that employs goodness of fit for each possible models,
with R program. 739 suitable shrubs were mapped,
with a density of 0.62 shrubs/ha. All of the 42 nests
studied were located in shrubs, with a density of 0.35
pairs/10 ha. The mean distance of occupied shrubs from
the nearest road was 12.5 m. In 76 % of the cases the
nests were positioned less than 25 meters from roads.
The analysis of the relative importance of every variable
for the models showed that the road distance is one of
the most important variables in relation to the probability
of Red-backed Shrike nesting in the suitable shrubs.
The preliminary results suggest that in homogeneous
agricultural landscapes, Red-backed Shrike seems to
build the nest mainly on the suitable shrubs nearest to
the roads, preferring these also if there are other available
shrubs with similar characteristics which are located
away from roads. It is reasonable to argue that suitable
shrub for nesting and the contemporary presence of
bare soil or open spaces for hunting, both of which exist
close to countryside roads, might represent the favorable
components of the breeding habitat selections of
Red-backed Shrikes. Our results could provide useful
indications for the census techniques and conservation
of the species; however, more accurate researches are
needed to better explain their irregular distribution in
agricultural landscapes
Altitude distribution of breeding sites of Red-backed Shrikes Lanius collurio in agricultural environments of Pesaro-Urbino province, Central Italy
No full textRelative importance of marginal vegetation (shrubs, hedgerows, isolated trees) surrogate of HNV farmland for bird species distribution in Central Italy
No full textThe marginal and unproductive elements of farmland landscapes, such as shrubs, hedgerows, isolated
trees and uncultivated patches, represent key habitats for many bird species, as far as nesting, feeding
and protection are concerned. Anyway this marginal vegetation has been removed due to the agricultural
intensification which occurred in Europe during the last decades. In this study, the environmental variables
known as marginal vegetation, which explain the presence and distribution of farmland bird species,
were analyzed using Generalized Linear Models and hierarchical partitioning protocol. Our results have
quantified the total contribution of marginal vegetation on the presence of farmland bird species and also
the relative importance of every type of marginal vegetation. These results confirm how these elements,
used also as one indication of high nature values of farmlands (HNV), are fit for studies on farmland birds
distribution in Central Italy. Some species were more related to hedgerows, while others were related
primarily to shrubs and others also to uncultivated marginal patches. The quantification of relative importance
of each marginal vegetation is an useful tool for landscape restoration planning. However, as the
relative importance was different for each bird species, the studies on farmland birds occurrence remain
key to improve the accuracy of predictive frameworks
Quantifying effects of spatial heterogeneity of farmlands on bird species richness by means of similarity index pairwise.
No full textMany studies have shown how intensification of farming is the main cause of loss biodiversity in these environments. During the last decades, agroecosystems in Europe have changed drastically, mainly due to mechanization of agriculture. In this work, species richness in bird communities was examined on a gradient of spatial heterogeneity of farmlands, in order to quantify its effects. Four categories of farmland spatial heterogeneity were defined, based on landscape and landuse parameters. The impact of features increasing the spatial heterogeneity was quantified comparing the similarity indexes between bird communities in several farmlands of Central Italy. The effects of environmental variables on bird richness were analyzed using GLM. The results highlighted that landscape features surrogates of high nature values (HNVs) of farmlands can increase more than 50% the bird species richness. The features more related to bird richness were hedgerows, scattered shrubs, uncultivated patches, and powerlines. The results confirm that the approach based on HNV for evaluating the farmlands is also suitable in order to study birds’ diversity. However, some species are more sensitive to heterogeneity, while other species occupy mainly homogeneous farmlands. As a consequence, different conservation methods must be considered for each farmland bird species
Importance of road proximity for the nest site selection of the Red-backed shrike Lanius collurio in an agricultural environment in Central Italy
Full text linkPlasticity of habitat selection by Red-backed Shrikes (Lanius collurio) breeding in different landscapes
No full textBreeding habitat and nesting site of the Red-backed Shrike Lanius collurio in farmland of the Marche region, Italy
No full textIn this work we studied some characteristics of nesting sites of red-backed shrike Lanius collurio in some areas of the Marche
Region (Central Italy). These areas are characterized by a temperate climate and by mainly agricultural cover. We analyzed the breeding site macrohabitat and the nest microhabitat. Results showed a prevalence of shrubs, most commonly Prunus spinosa and Rosa canina, as nest support. The nest is generally located at mid height (1.39 m) and in the midpoint of the shrub. Nesting sites were located mainly in the edge zone of the vegetation patches and nearby the roads. In over 65 % of cases the nests were built less than 5 meters far from roads.
Results highlight the importance of some vegetation species and the presence of certain environmental structures (presence of shrubs, tree rows and other marginal habitats of farmland areas) for the preservation of this species, whose conservation status in Italy and Europe is currently unfavourable
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