A species' diet is highly dependent on the availability of food resources in space and time, as well as on intrinsic factors such as sex or age. Accurate assessments of variations in the diet composition of bird populations across spatial scales, seasons and demographic groups are essential not only for understanding the basic ecology of species, but also for the conservation of endangered ones. However, our current knowledge about how birds' diet change according to spatio-temporal variations or intrinsic factors is very limited.
View Article and Find Full Text PDFMonitoring zoonoses in urban environments is of great relevance, where the incidence of certain pathogens may be higher and where population density makes the spread of any contagious disease more likely. In this study we applied a metabarcoding approach to study potentially zoonotic pathogens in faecal samples of 9 urban vertebrate species. We applied this methodology with two objectives.
View Article and Find Full Text PDFDispersal of individuals and gene flow are crucial aspects to maintain genetic diversity and viability of populations, especially in the case of threatened species. Landscape composition and structure may facilitate or limit individual movement within and among populations. We used a landscape genetics approach to assess the connectivity patterns of the threatened Dupont's lark ( subsp.
View Article and Find Full Text PDFCompetition is a prominent mechanism driving population dynamics and structuring community assemblage, which can be investigated by linking shifts in species' ecological niche and the densities of sympatric species because the ecological release from competitive constraints is a density-dependent process. In this work we determine how a steppe passerine community segregates their ecological niches and evaluate the role of competition in inducing changes in the ecological niche of species. We built multidimensional ecological niches (with Gaussian kernel density estimators) using data on the habitat features used by 10 bird species collected from seven sites in the natural steppes of Central Spain over 2 consecutive years.
View Article and Find Full Text PDFCommun Earth Environ
September 2022
European green agricultural policies have been relaxed to allow cultivation of fallow land to produce animal feed and meet shortfalls in exports from Ukraine and Russia. However, conversion of semi-natural habitats will disproportionately impact long term biodiversity and food security.
View Article and Find Full Text PDFWind energy has experienced a notable development during the last decades, driving new challenges for animal communities. Although bird collisions with wind turbines and spatial displacement due to disturbance have been widely described in the literature, other potential impacts remain unclear. In this study, we addressed the effect of turbine noise on the vocal behaviour of a threatened shrub-steppe passerine highly dependent on acoustic communication, the Dupont's lark Chersophilus duponti.
View Article and Find Full Text PDFIberian natural steppes have traditionally been used for extensive sheep grazing, which has been noted to be positively associated with steppe bird abundance and diversity. Sheep numbers in Spain, which harbors the largest European populations of many steppe bird species, decreased by 9.2 million (37.
View Article and Find Full Text PDFSteppe lands in Europe are critically affected by habitat loss and fragmentation, and hold over 50% of IUCN Red List bird species in Europe. Dupont's Lark is a threatened steppe-specialist passerine whose European geographic range is restricted to Spain, with less than 2000 pairs and an annual population decline of - 3.9%.
View Article and Find Full Text PDFBackground: Dupont's Lark is an endangered bird, whose fragmented distribution in Europe is entirely restricted to Spain. This lark, suffering pronounced population decline and range contraction, inhabits steppes that have long been used for grazing sheep and are now threatened by rural abandonment and land use changes. Thus, for conservation of the lark, increasing knowledge about the connectivity of the Spanish metapopulation and identifying the most important connectivity nodes are crucial.
View Article and Find Full Text PDFMultidimensional approaches must be employed when addressing habitat use patterns. In this study, we aim to elucidate the hierarchical nature of space use by species inhabiting fragmented landscapes, using the threatened Dupont's lark (Chersophilus duponti). The intensity of space use by Dupont's lark was estimated using the Kernel Density Function on territory locations in 2015.
View Article and Find Full Text PDFFarmland bird populations have strongly declined across Europe over the last decades due to agriculture intensification, despite successive reforms of EU's Common Agricultural Policy (CAP). In parallel, CAP has led to a reduction of fallow land, a critical habitat for biodiversity in agroecosystems. Fallow land in Spain, a country harboring the largest European populations of many endangered farmland birds, has decreased by 1.
View Article and Find Full Text PDFIn this work, we analyse factors explaining the distribution and range regression of Dupont's lark in Spain, the only European country in which this threatened alaudid is present. Dupont's lark is an extremely elusive and scarce species, distributed across a reduced and strongly fragmented range, showing a metapopulational structure with unknown dispersive and connective mechanisms. We used maximum entropy modelling (Maxent) on nearly 15,000 Dupont's lark observations (1985-2015) to assess the probability of presence at a 1 km resolution across its European range.
View Article and Find Full Text PDFBackground: Steppe-birds face drastic population declines throughout Europe. The Dupont's lark is an endangered steppe-bird species whose European distribution is restricted to Spain. This scarce passerine bird could be considered an 'umbrella species', since its population trends may reveal the conservation status of shrub-steppes.
View Article and Find Full Text PDFInterspecific competition is a dominant force in animal communities that induces niche shifts in ecological and evolutionary time. If competition occurs, niche expansion can be expected when the competitor disappears because resources previously inaccessible due to competitive constraints can then be exploited (i.e.
View Article and Find Full Text PDFWe modelled the distribution of two vulnerable steppe birds, Otis tarda and Tetrax tetrax, in the Western Palearctic and projected their suitability up to the year 2080. We performed two types of models for each species: one that included environmental and geographic variables (space-included model) and a second one that only included environmental variables (space-excluded model). Our assumption was that ignoring geographic variables in the modelling procedure may result in inaccurate forecasting of species distributions.
View Article and Find Full Text PDFBiotic interactions and land uses have been proposed as factors that determine the distribution of the species at local scale. The presence of heterospecifics may modify the habitat selection pattern of the individuals and this may have important implications for the design of effective conservation strategies. However, conservation proposals are often focused on a single flagship or umbrella species taken as representative of an entire assemblage requirements.
View Article and Find Full Text PDFCompetition arises when two co-occuring species share a limiting resource. Potential for competition is higher when species have coexisted for a short time, as it is the case for herbivores and livestock introduced in natural systems. Sheep, introduced in the late 19(th) century in Patagonia, bear a great resemblance in size and diet to the guanaco, the main native herbivore in Patagonia.
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