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inter-individual differences in foraging tactics of a colonial raptor: consistency, weather effects, and fitness correlates.consistent inter-individual differences in behavioural phenotypes may entail differences in energy efficiency and expenditure, with different fitness payoffs. in colonial-breeding species, inter-individual differences in foraging behaviour may evolve to reduce resource use overlap among conspecifics exploiting shared foraging areas. furthermore, individual differences in foraging behaviour may covary with individual characteristics, such as sex or physiological conditions.202032587702
sex interacts with age-dependent change in the abundance of lice-infesting amur falcons (falco amurensis).sex-biassed and age-biassed parasite infections are common in nature, including ectoparasites-vertebrate host systems. we investigated the effect of amur falcons' sex, age and body size on the abundance of their lice at a migratory stopover site, where the falcons' habitat use and behaviour are more homogeneous across sex and age categories than during the breeding season. we sampled amur falcons in nagaland, india at major roosting sites in 2016. we applied generalized linear models (with negat ...202032556537
analysis of movement recursions to detect reproductive events and estimate their fate in central place foragers.recursive movement patterns have been used to detect behavioral structure within individual movement trajectories in the context of foraging ecology, home-ranging behavior, and predator avoidance. some animals exhibit movement recursions to locations that are tied to reproductive functions, including nests and dens; while existing literature recognizes that, no method is currently available to explicitly target different types of revisited locations. moreover, the temporal persistence of recursi ...202032518652
extreme events are more likely to affect the breeding success of lesser kestrels than average climate change.climate change is predicted to severely impact interactions between prey, predators and habitats. in southern europe, within the mediterranean climate, herbaceous vegetation achieves its maximum growth in middle spring followed by a three-month dry summer, limiting prey availability for insectivorous birds. lesser kestrels (falco naumanni) breed in a time-window that matches the nestling-rearing period with the peak abundance of grasshoppers and forecasted climate change may impact reproductive ...202032350294
home, dirty home: effect of old nest material on nest-site selection and breeding performance in a cavity-nesting raptor.the quality of a breeding site may have major fitness consequences. a fundamental step to understanding the process of nest-site selection is the identification of the information individuals use to choose high-quality nest sites. for secondary cavity-nesting bird species that do not add nest lining material, organic remains (faeces, pellets) accumulated inside nest cavities during previous breeding events may be a cue for high-quality nest-sites, as they contain information about past successfu ...201830538728
effectiveness of a mitigation measure for the lesser kestrel (falco naumanni) in wind farms in spain.central-eastern spain is characterised as being a flat and relatively open landscape, greatly used for agricultural purposes and with a high density of wind installations. this landscape also hosts a large population of the lesser kestrel (falco naumanni), one of the species most threatened by collisions with wind turbines. during a ten-year period, we analysed bird mortality by recording deaths on three wind farms (wf), cerro del palo, cerro calderón and la muela i, located in the province of c ...201930423547
spatial segregation of home ranges between neighbouring colonies in a diurnal raptor.enhancement 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 (fal ...201830082763
using genetic markers to unravel the origin of birds converging towards pre-migratory sites.identifying patterns of individual movements in spatial and temporal scales can provide valuable insight into the structure of populations and the dynamics of communities and ecosystems. especially for migrating birds, that can face a variety of unfavorable conditions along their journey, resolving movements of individuals across their annual cycle is necessary in order to design better targeted conservation strategies. here, we studied the movements of a small migratory falcon, the lesser kestr ...201829844462
colonization with enterobacteriaceae-producing esbls, ampcs, and oxa-48 in wild avian species, spain 2015-2016.antibiotic resistance is a global threat of complex and changeable epidemiology. the role of wild birds in the dissemination of antibacterial resistance might be underestimated. we studied the cloacal colonization by cefotaxime-resistant enterobacteriaceae in 668 wild birds in spain. eighty-eight wild birds (13.2%) of 28 species carried cefotaxime-resistant isolates; 58 of them (8.7%) carried extended-spectrum β-lactamases (esbls) and 15 (2.5%) plasmid-mediated ampcs of the blacit family. the 58 ...201829782210
genetic favoring of pheomelanin-based pigmentation limits physiological benefits of coloniality in lesser kestrels falco naumanni.pheomelanin contributes to the pigmentation phenotype of animals by producing orange and light brown colors in the integument. however, pheomelanin synthesis in melanocytes requires consumption of glutathione (gsh), the most important intracellular antioxidant. therefore, a genetic control favoring the production of large amounts of pheomelanin for pigmentation may lead to physiological costs under environmental conditions that promote oxidative stress. we investigated this possibility in the co ...201728805337
combined use of tri-axial accelerometers and gps reveals the flexible foraging strategy of a bird in relation to weather conditions.tri-axial accelerometry has proved to be a useful technique to study animal behavior with little direct observation, and also an effective way to measure energy expenditure, allowing a refreshing revisit to optimal foraging theory. this theory predicts that individuals should gain the most energy for the lowest cost in terms of time and energy when foraging, in order to maximize their fitness. however, during a foraging trip, central-place foragers could face different trade-offs during the comm ...201728591181
correlated velocity models as a fundamental unit of animal movement: synthesis and applications.continuous time movement models resolve many of the problems with scaling, sampling, and interpretation that affect discrete movement models. they can, however, be challenging to estimate, have been presented in inconsistent ways, and are not widely used.201728496983
a few long versus many short foraging trips: different foraging strategies of lesser kestrel sexes during breeding.in species with biparental care both members of the breeding pair cooperate to raise the offspring either by assisting each other in every reproductive task or by specializing in different ones. the latter case is known as reproductive role specialization. raptors are considered one of the most role-specialized groups, but little is known about parental behavior away from the nest. until the advent of biologgers, avian role specialization was traditionally studied with direct observations at the ...201728451434
how to plan reintroductions of long-lived birds.reintroductions have been increasingly used for species restoration and it seems that this conservation tool is going to be more used in the future. nevertheless, there is not a clear consensus about the better procedure for that, consequently a better knowledge of how to optimize this kind of management is needed. here we examined the dynamics of released long-lived bird populations (lesser kestrel, falco naumanni, bonelli's eagle aquila fasciata, and bearded vulture gypaetus barbatus) in objec ...201728445473
an integrated analysis of micro- and macro-habitat features as a tool to detect weather-driven constraints: a case study with cavity nesters.the effects of climate change on animal populations may be shaped by habitat characteristics at both micro- and macro-habitat level, however, empirical studies integrating these two scales of observation are lacking. as analyses of the effects of climate change commonly rely on data from a much larger scale than the microhabitat level organisms are affected at, this mismatch risks hampering progress in developing understanding of the details of the ecological and evolutionary responses of organi ...201728319183
why do kestrels soar?individuals allocate considerable amounts of energy to movement, which ultimately affects their ability to survive and reproduce. birds fly by flapping their wings, which is dependent on the chemical energy produced by muscle work, or use soaring-gliding flight, in which chemical energy is replaced with energy harvested from moving air masses, such as thermals. flapping flight requires more energy than soaring-gliding flight, and this difference in the use of energy increases with body mass. how ...201526689780
organochlorine and mercury residues in eggs of the lesser kestrel (falco naumanni) from a long term study in the eastern mediterranean.organochlorine and mercury residues were analyzed in unhatched eggs of the lesser kestrel (falco naumanni) (2002-2012) in central greece. concentrations graded as ∑ddts > ∑pcbs > hcb > ∑hchs > ∑chlordanes. temporal declines were found in the concentrations of ∑ddts, ∑hchs and ∑chlordanes but not in hg, hcb and ∑pcbs. teqs of pcbs and their degree of metabolisation showed no time trend. the reproductive parameters showed neither a temporal trend nor a significant year effect. no relationships occ ...201526386205
the whole mitochondrial genome of the lesser kestrel (falco naumanni).falconiformes include most of the predatory birds, they play crucial role in maintaining the balance of ecology system. to further illustrate the phylogenetic status for the species of falconiformes, the entire mitochondrial dna (mtdna) genome of falco naumanni was amplified and sequenced, further phylogenetic analysis was performed by incorporating with other 8 entire mtdna genomes representing 8 species of predatory birds by taking the apus apus and haematopus ater as out-groups. our results i ...201626006284
social phenotype extended to communities: expanded multilevel social selection analysis reveals fitness consequences of interspecific interactions.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 mul ...201525688567
genetic characterization of oropharyngeal trichomonad isolates from wild birds indicates that genotype is associated with host species, diet and presence of pathognomonic lesions.oropharyngeal trichomonad isolates of wild birds from spain were studied. a total of 1688 samples (1214 of predator birds and 474 of prey species) from wildlife recovery centres and scientific bird-ringing campaigns were analysed from 2011 to 2013. the overall infection prevalence was 20.3% (11.4% in predator birds and 43.3% in prey species). pathognomonic lesions were present in 26% of the infected birds (57.3% in predator birds and 4.9% in prey species). the most commonly parasitized species w ...201425262786
determinants and short-term physiological consequences of pha immune response in lesser kestrel nestlings.individual immune responses are likely affected by genetic, physiological, and environmental determinants. we studied the determinants and short-term consequences of phytohaemagglutinin (pha) induced immune response, a commonly used immune challenge eliciting both innate and acquired immunity, on lesser kestrel (falco naumanni) nestlings in semi-captivity conditions and with a homogeneous diet composition. we conducted a repeated measures analyses of a set of blood parameters (carotenoids, trigl ...201424807828
foraging habitat quality constrains effectiveness of artificial nest-site provisioning in reversing population declines in a colonial cavity nester.among birds, breeding numbers are mainly limited by two resources of major importance: food supply and nest-site availability. here, we investigated how differences in land-use and nest-site availability affected the foraging behaviour, breeding success and population trends of the colonial cavity-dependent lesser kestrel falco naumanni inhabiting two protected areas. both areas were provided with artificial nests to increase nest-site availability. the first area is a pseudo-steppe characterize ...201323484016
an automatic weighting system for wild animals based in an artificial neural network: how to weigh wild animals without causing stress.this paper proposes a novel and autonomous weighing system for wild animals. it allows evaluating changes in the body weight of animals in their natural environment without causing stress. the proposed system comprises a smart scale designed to estimate individual body weights and their temporal evolution in a bird colony. the system is based on computational intelligence, and offers valuable large amount of data to evaluate the relationship between long-term changes in the behavior of individua ...201323449117
the eye in the sky: combined use of unmanned aerial systems and gps data loggers for ecological research and conservation of small birds.technological advances for wildlife monitoring have expanded our ability to study behavior and space use of many species. but biotelemetry is limited by size, weight, data memory and battery power of the attached devices, especially in animals with light body masses, such as the majority of bird species. in this study, we describe the combined use of gps data logger information obtained from free-ranging birds, and environmental information recorded by unmanned aerial systems (uass). as a case s ...201223239979
seropositivity and risk factors associated with toxoplasma gondii infection in wild birds from spain.toxoplasma gondii is a zoonotic intracellular protozoan parasite of worldwide distribution that infects many species of warm-blooded animals, including birds. to date, there is scant information about the seropositivity of t. gondii and the risk factors associated with t. gondii infection in wild bird populations. in the present study, t. gondii infection was evaluated on sera obtained from 1079 wild birds belonging to 56 species (including falconiformes (n = 610), strigiformes (n = 260), ciconi ...201122216311
sources of variation for nutritional condition indices of the plasma of migratory lesser kestrels in the breeding grounds.although published information on reference values for biochemical parameters in birds of prey has increased during the last years, little is known on their sources of variation. we used an insectivorous and small migratory raptor species, the lesser kestrel falco naumanni, as a model. we looked for sources of variation of nutritional biochemical parameters (i.e. triglycerides, cholesterol, uric acid and urea) of both nestlings and adults. reference values indicated that, as a rule, lesser kestr ...201121864701
lifetime fitness correlates of natal dispersal distance in a colonial bird.1. obtaining empirical evidence of the consequences of dispersal distance on fitness is challenging in wild animals because long-term, unbiased data on reproduction, survival and movement are notoriously difficult to obtain. 2. lifetime fitness correlates of natal dispersal distance were studied in an isolated population of the facultatively colonial lesser kestrel falco naumanni (fleischer) monitored during 8 years at north-eastern spain, where most birds (83%) dispersed from their natal colony ...201221644982
sampling strategies for accurate computational inferences of gametic phase across highly polymorphic major histocompatibility complex loci.genes of the major histocompatibility complex (mhc) are very popular genetic markers among evolutionary biologists because of their potential role in pathogen confrontation and sexual selection. however, mhc genotyping still remains challenging and time-consuming in spite of substantial methodological advances. although computational haplotype inference has brought into focus interesting alternatives, high heterozygosity, extensive genetic variation and population admixture are known to cause in ...201121615903
permanent genetic resources added to molecular ecology resources database 1 may 2009-31 july 2009.this article documents the addition of 512 microsatellite marker loci and nine pairs of single nucleotide polymorphism (snp) sequencing primers to the molecular ecology resources database. loci were developed for the following species: alcippe morrisonia morrisonia, bashania fangiana, bashania fargesii, chaetodon vagabundus, colletes floralis, coluber constrictor flaviventris, coptotermes gestroi, crotophaga major, cyprinella lutrensis, danaus plexippus, fagus grandifolia, falco tinnunculus, fle ...200921564933
efficiency of a protected-area network in a mediterranean region: a multispecies assessment with raptors.three different systems of designating protected areas in a mediterranean region in southeastern spain were studied, referring to their effectiveness and efficiency for protecting both the breeding territories and the suitable habitat of a set of ten raptor species. taking into consideration the varying degrees of endangerment of these species, a map of multispecies conservation values was also drawn up and superimposed on the three protected-area systems studied. in order to compare the levels ...201121374090
molecular evolution of the toll-like receptor multigene family in birds.toll-like receptors (tlr) are membrane-bound sensors of the innate immune system that recognize invariant and distinctive molecular features of invading microbes and are also essential for initiating adaptive immunity in vertebrates. the genetic variation at tlr genes has been directly related to differential pathogen outcomes in humans and livestock. nonetheless, new insights about the impact of tlrs polymorphism on the evolutionary ecology of infectious diseases can be gained through the inves ...201121239391
natural cross chlamydial infection between livestock and free-living bird species.the study of cross-species pathogen transmission is essential to understanding the epizootiology and epidemiology of infectious diseases. avian chlamydiosis is a zoonotic disease whose effects have been mainly investigated in humans, poultry and pet birds. it has been suggested that wild bird species play an important role as reservoirs for this disease. during a comparative health status survey in common (falco tinnunculus) and lesser (falco naumanni) kestrel populations in spain, acute gammapa ...201020976071
mhc diversity and differential exposure to pathogens in kestrels (aves: falconidae).pathogen diversity is thought to drive major histocompatibility complex (mhc) polymorphism given that host's immune repertories are dependent on antigen recognition capabilities. here, we surveyed an extensive community of pathogens (n = 35 taxa) and mhc diversity in mainland versus island subspecies of the eurasian kestrel falco tinnunculus and in a sympatric mainland population of the phylogenetically related lesser kestrel falco naumanni. insular subspecies are commonly exposed to impoverishe ...201020074317
evidence of subtle departures from mendelian segregation in a wild lesser kestrel (falco naumanni) population.some alleles are inherited more frequently than expected from mendel's rule. this phenomenon, known as transmission ratio distortion (trd), is found in a broad variety of taxa, but it is thought to be unusual and occurs at a low frequency in any particular population. here, we used seven microsatellite markers to search for possible trd in a wild lesser kestrel (falco naumanni) population. among the nine alleles analysed with at least 200 known meioses for each sex, we found that two of them (15 ...201019953119
temporal variation of heterozygosity-based assortative mating and related benefits in a lesser kestrel population.heterozygosity as a target of mate choice has received much attention in recent years and there is growing evidence supporting its role in the evolution of mate preferences. in this study we analyse mating patterns in relation to heterozygosity in a lesser kestrel (falco naumanni) population intensively monitored over six study years (2002-2007). the magnitude of heterozygosity-based assortative mating varied over time, being particularly patent in the last study years (2006, 2007). we have foun ...200919878409
the role of mycoplasmas in a conservation project of the lesser kestrel (falco naumanni).the lesser kestrel (falco naumanni) is one of the most endangered bird species in europe, and a captive breeding and reintroduction project was established. a breeding project is vulnerable to pathogens, e.g., mycoplasmas, reducing the reproductive success and carrying the risk to release pathogens with the birds to the wild. therefore, 18 infertile eggs and 43 dead in shell embryos of the breeding project, as well as 27 nestlings and 34 adult birds of the captive and three different free-rangin ...200819166056
strong philopatry derived from capture-recapture records does not lead to fine-scale genetic differentiation in lesser kestrels.1. the integration of capture-recapture and molecular approaches can improve our understanding of the consequences of habitat fragmentation on population connectivity. here we employed microsatellites to test dispersal hypotheses derived from intense and long-term ringing programmes of the lesser kestrel falco naumanni in western europe. 2. re-encounters of 1308 marked individuals in spain have revealed that most first-time breeders settled within 10 km from their natal colony, with a negative a ...200919054221
a conceptual model for assessing risks in a mediterranean natura 2000 network site.every year millions of tons of chemical products are disposed to the environment as a result of human activities, with deleterious consequences to biodiversity. in europe the biodiversity policy basis for action is provided by the birds and the habitats directives. according to these directives a network of protected areas is being built across eu countries encompassing the natura 2000 network. but the management plans of these protected areas do not require an ecotoxicological assessment of che ...200918990432
characteristics of loci and individuals are associated with germline microsatellite mutation rates in lesser kestrels (falco naumanni).although microsatellites are one of the most popular tools in genetic studies, their mutational dynamics and evolution remain unclear. here, we apply extensive pedigree genotyping to identify and analyze the patterns and factors associated with de novo germline mutations across nine microsatellite loci in a wild population of lesser kestrels (falco naumanni). a total of 10 germline mutations events were unambiguously identified in four loci, yielding an average mutation rate of 2.96x10(-3). acro ...200818973763
population fragmentation leads to isolation by distance but not genetic impoverishment in the philopatric lesser kestrel: a comparison with the widespread and sympatric eurasian kestrel.population fragmentation is a widespread phenomenon usually associated with human activity. as a result of habitat transformation, the philopatric and steppe-specialist lesser kestrel falco naumanni underwent a severe population decline during the last century that increased population fragmentation throughout its breeding range. in contrast, the ubiquitous eurasian kestrel falco tinnunculus did not suffer such adverse effects, its breeding range still remaining rather continuous. using microsat ...200918854856
genetic characterization, distribution and prevalence of avian pox and avian malaria in the berthelot's pipit (anthus berthelotii) in macaronesia.exotic pathogens have been implicated in the decline and extinction of various native-island-bird species. despite the fact that there is increasing concern about the introduction of diseases in island ecosystems, little is known about parasites in the islands of macaronesia. we focus on berthelot's pipit (anthus berthelotii), an endemic and widespread macaronesian bird species, using a combination of field studies and molecular techniques to determine: (1) the range and prevalence of avian pox ...200818762985
first description of malignant retrobulbar and intracranial teratoma in a lesser kestrel (falco naumanni).teratomas are defined as germ cell origin neoplasms that can be rarely found in either humans or animals. their most common localization is the gonads, although extragonadal localization has also been observed. in avian medicine, there is scarce literature about the occurrence of teratomas and their clinical implications, and this is mainly in wildlife birds . for this reason, we report the first description of a teratoma with both retrobulbar and intracranial locations in a 10-day-old chick of ...200818622858
individual genetic diversity correlates with the size and spatial isolation of natal colonies in a bird metapopulation.the genetic consequences of small population size and isolation are of central concern in both population and conservation biology. organisms with a metapopulation structure generally show effective population sizes that are much smaller than the number of mature individuals and this can reduce genetic diversity especially in small sized and isolated subpopulations. here, we examine the association between heterozygosity and the size and spatial isolation of natal colonies in a metapopulation of ...200818505717
extensive polymorphism and geographical variation at a positively selected mhc class ii b gene of the lesser kestrel (falco naumanni).understanding the selective forces that shape genetic variation in natural populations remains a high priority in evolutionary biology. genes at the major histocompatibility complex (mhc) have become excellent models for the investigation of adaptive variation and natural selection because of their crucial role in fighting off pathogens. here we present one of the first data sets examining patterns of mhc variation in wild populations of a bird of prey, the lesser kestrel, falco naumanni. we rep ...200818489548
truncated power laws reveal a link between low-level behavioral processes and grouping patterns in a colonial bird.departures from power law group size frequency distributions have been proposed as a useful tool to link individual behavior with population patterns and dynamics, although examples are scarce for wild animal populations.200818431479
genetic consequences of natal dispersal in the colonial lesser kestrel.dispersal is a life-history trait that plays a fundamental role in population dynamics, influencing evolution, species distribution, and the genetics and structure of populations. in spite of the fact that dispersal has been hypothesized to be an efficient behavioural mechanism to avoid inbreeding, the expected relationship between dispersal and mate relatedness still remains controversial. here, we examine the genetic consequences of natal dispersal, namely the higher chance of obtaining geneti ...200818346124
no relationship between individual genetic diversity and prevalence of avian malaria in a migratory kestrel.insight into the genetic basis of malaria resistance is crucial for understanding the consequences of this parasite group on animal populations. here, we analyse the relationship between genotypic variation at 11 highly variable microsatellite loci and prevalence of three different lineages of avian malaria, two plasmodium (rtsr1, lk6) and one haemoproteus (lk2), in a wild population of the endangered lesser kestrel (falco naumanni). although we used a large sample size (584 typed individuals), ...200717944853
characterization, polymorphism, and evolution of mhc class ii b genes in birds of prey.during the last decade, the major histocompatibility complex (mhc) has received much attention in the fields of evolutionary and conservation biology because of its potential implications in many biological processes. new insights into the gene structure and evolution of mhc genes can be gained through study of additional lineages of birds not yet investigated at the genomic level. in this study, we characterized mhc class ii b genes in five families of birds of prey (accipitridae, pandionidae, ...200717925996
risk of ectoparasitism and genetic diversity in a wild lesser kestrel population.parasites and infectious diseases are major determinants of population dynamics and adaptive processes, imposing fitness costs to their hosts and promoting genetic variation in natural populations. in the present study, we evaluate the role of individual genetic diversity on risk of parasitism by feather lice degeeriella rufa in a wild lesser kestrel population (falco naumanni). genetic diversity at 11 microsatellite loci was associated with risk of parasitism by feather lice, with more heterozy ...200717845443
increase of heterozygosity in a growing population of lesser kestrels.the lesser kestrel (falco naumanni) suffered a sharp population decline over much of its european distribution range in the middle of the twentieth century. still declining in some areas, the species has recently experienced a notable population recovery in certain regions. we examined the genetic diversity variation in a growing population of lesser kestrels from central spain over a 6-year period (2000-2005). the population studied showed a rapid demographic expansion, increasing in the number ...200717609170
egg production and individual genetic diversity in lesser kestrels.fecundity is an important component of individual fitness and has major consequences on population dynamics. despite this, the influence of individual genetic variability on egg production traits is poorly known. here, we use two microsatellite-based measures, homozygosity by loci and internal relatedness, to analyse the influence of female genotypic variation at 11 highly variable microsatellite loci on both clutch size and egg volume in a wild population of lesser kestrels (falco naumanni). ge ...200717561899
genetic characterization of avian malaria (protozoa) in the endangered lesser kestrel, falco naumanni.we genetically analyzed avian malaria (protozoa) isolated from lesser kestrels (falco naumanni) breeding in la mancha, central spain. a total of 586 adult individuals were screened for blood parasites using a very efficient polymerase chain reaction approach that amplifies a partial segment (498 bp) of the cytochrome b gene of avian malaria of the genera haemoproteus and plasmodium. the prevalence of plasmodium was 8.2%, and the prevalence of haemoproteus was 4.1%. sequence analyses revealed six ...200717514379
the role of despotism and heritability in determining settlement patterns in the colonial lesser kestrel.avian colony size variation is an evolutionary puzzle in terms of unequal fitness payoffs. we used a long-term marked lesser kestrel (falco naumanni) population, where individual fitness increases with colony size, to test whether subordinates are evicted despotically from the largest colonies. yearlings were smaller and lighter, were more attacked than expected, and lost most disputes over nest holes with older birds. agonistic interactions increased with colony size; consequently, most first b ...200717211799
colony size selection determines adult survival and dispersal preferences: allee effects in a colonial bird.avian coloniality traditionally has been investigated by examining how breeding success varies with colony size, but other crucial fitness components rarely have been examined. this may lead to wrong conclusions because unmeasured parameters may change the final fitness balance. we used multistate capture-recapture models to investigate adult survival and dispersal in relation to colony size within a long-term monitored population of lesser kestrels (falco naumanni). nest predation probability d ...200516032568
organochlorine and heavy metal contamination in non-viable eggs and its relation to breeding success in a spanish population of lesser kestrels (falco naumanni).residues of organochlorines, polychlorinated biphenyls (pcbs), and heavy metals (mercury, cadmium, lead, copper and zinc) were measured in unhatched eggs of lesser kestrels (falco naumanni) collected in southern spain in 1988-1991. although contaminants were detected in all eggs, the amounts were generally below levels known to have negative effects on reproduction. this is consistent with the relatively high hatching rate (about 80%) in the studied population. the nestling mortality was severe, ...199315091790
a twelve-month study of west nile virus antibodies in a resident and a migrant species of kestrels in israel.two species of kestrel, the common and lesser, were caught each month at three geographically defined locations in israel over a 12-month period, and a total of 306 blood samples were examined for west nile virus neutralizing antibodies. the prevalences and mean antibody titers were analyzed statistically by the multiple linear regression model and were shown to be significantly affected by two of the independent variables, location and age of the bird. the season had no overall effect on preval ...200415018769
the effects of the minimum threshold condition for breeding on offspring sex-ratio adjustment in the lesser kestrel.we propose a model for sex-ratio adjustment complementary to that of trivers and willard. in addition to the three basic assumptions of the trivers-willard model, our model assumes that the sex with more variable reproductive success (normally male) is also the sex less constrained for reproduction. this assumption seems realistic, because several studies have demonstrated that poor-condition males may adopt alternative mating strategies and sire some offspring, whereas females have physiologica ...200111475054
protective association and breeding advantages of choughs nesting in lesser kestrel coloniessome bird species may breed close to aggressive predators to reduce predation risk by more dangerous, generalist predators. we tested this protective nesting association hypothesis by studying solitary choughs, pyrrhocorax pyrrhocoraxbreeding within or outside lesser kestrel, falco naumannicolonies in northern spain (1993-1994). we found 27 potential predators of choughs and kestrels and confirmed predation on adults and nests of both species by at least eight common predators. we experimentally ...19979268465
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