Search results for " lesser kestrel"

Genetic structure of a patchily distributed philopatric migrant: implications for management and conservation

2017

Significant demographic fluctuations can have major genetic consequences in wild populations. The lesser kestrel (Falco naumanni) has suffered both population declines and range fragmentation during the second half of the 20th century. In this study we analysed multilocus microsatellite data to assess the genetic structure of the species. Our analysis revealed significant genetic structuring of lesser kestrel populations, not only at the cross-continental scale, but also regionally within the Central and Eastern (CE) Mediterranean region. We detected signs of genetic bottlenecks in some of the peripheral populations coupled with small effective population sizes. Values of genetic differenti…

Barrier crossings and winds shape daily travel schedules and speeds of a flight generalist

2021

External factors such as geography and weather strongly affect bird migration influencing daily travel schedules and flight speeds. For strictly thermal-soaring migrants, weather explains most seasonal and regional differences in speed. Flight generalists, which alternate between soaring and flapping flight, are expected to be less dependent on weather, and daily travel schedules are likely to be strongly influenced by geography and internal factors such as sex. We GPS-tracked the migration of 70 lesser kestrels (Falco naumanni) to estimate the relative importance of external factors (wind, geography), internal factors (sex) and season, and the extent to which they explain variation in trav…

Habitat- and density-dependent demography of a colonial raptor in Mediterranean agro-ecosystems

2016

Agricultural intensification is considered the major cause of decline in farmland bird populations, especially in the Mediterranean region. Food shortage increased by the interaction between agricultural intensification and density-dependent mechanisms could influence the population dynamics of colonial birds.Weused demographic data on lesser kestrels (Falco naumanni), a key species of Mediterranean pseudo-steppes, to understand the importance of land-use changes and density-dependent mechanisms in the light of its fluctuating conservation status in the Western Palearctic. Our analysis indicated an important influence of land uses (artichokes, arable and grassland fields) and colony size on…

Nest aggregation and reproductive synchrony promote Lesser Kestrel Falco naumanni seasonal fitness

2013

Several factors promote coloniality by enhancing the fitness of colony members. In birds, spatial proximity among nests, breeder abundance and reproductive synchrony have been proposed as primary factors responsible for enhanced colonial defence and foraging success, which, in turn, enhance reproductive success. Whether these factors function synergistically or antagonistically remains, however, an open question due to the absence of an integrated analysis of their effects on fitness. We studied a large population of the Lesser Kestrel, Falco naumanni, a facultative colonial species, breeding in colonies of different sizes in their typical pseudo-steppe habitat. We quantified both the singu…

Effects of Nest and Colony Features on Lesser Kestrel (Falco naumanni) Reproductive Success

2012

The Lesser Kestrel is a facultative colonial raptor mostly breeding in man-made structures. During 2009-2011 we checked the fate of 545 nests found in 18 colonies located in south-eastern Sicily. We determined the reproductive success of breeding pairs by analysing the survival time of each egg to hatching ( n = 2,495) and each nestling to fledging ( n = 1,849) with the linear hazard model of survival times. We determined whether egg and nestling survival differed between years with a Gehan–Wilcoxon test. By Cox regressions, we related the survival times with nest and colony features. Egg and nestling survival times showed a strong annual effect. The two reproductive stages of the Lesser K…

Climate and land-use changes as determinants of lesser kestrel Falco naumanni abundance in Mediterranean cereal steppes (Sicily)

2010

Monitoring of lesser kestrels Falco naumanni is necessary to promote conservation of this vulnerable species. To this end, 35 colonies of this species located in the NNW and SE of Sicily were monitored from 2003 to 2009. Counts of the active colonies and resident pairs were modelled by loglinear Poisson regressions to assess population trends over the study period. Afterwards, a GLM with an analysis of covariance design and a backward removal stepwise regression was performed to relate the observed trend to local- or global-scale climatic variation and to local land-use changes. Colony counts provided a better fit to the loglinear models than pair counts. Loglinear models separated the incr…

Social phenotype extended to communities: expanded multilevel social selection analysis reveals fitness consequences of interspecific interactions.

2014

In social species, fitness consequences are associated with both individual and social phenotypes. Social selection analysis has quantified the contribution of conspecific social traits to individual fitness. There has been no attempt, however, to apply a social selection approach to quantify the fitness implications of heterospecific social phenotypes. Here, we propose a novel social selection based approach integrating the role of all social interactions at the community level. We extended multilevel selection analysis by including a term accounting for the group phenotype of heterospecifics. We analyzed nest activity as a model social trait common to two species, the lesser kestrel (Falc…

Spatial segregation of home ranges between neighbouring colonies in a diurnal raptor

2018

AbstractEnhancement of information transfer has been proposed as a key driver of the evolution of coloniality. Transfer of information on location of food resources implies that individuals from the same colony share foraging areas and that each colony can be associated to a specific foraging area. In colonial breeding vertebrates, colony-specific foraging areas are often spatially segregated, mitigating intercolony intraspecific competition. By means of simultaneous GPS tracking of lesser kestrels (Falco naumanni) from neighbouring colonies, we showed a clear segregation of space use between individuals from different colonies. Foraging birds from different neighbouring colonies had home r…

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…