| information collected during the post-breeding season guides future breeding decisions in a migratory bird. | breeding habitat choice and investment decisions are key contributors to fitness in animals. density of individuals is a well-known cue of habitat quality used for future breeding decisions, but accuracy of density cues decreases as individuals disperse from breeding sites. used nests remain an available information source also after breeding season, but whether such information is used for breeding decisions is less well known. we experimentally investigated whether migratory, cavity-nesting pi ... | 2020 | 32162073 |
| experimental study of the effect of preen oil against feather bacteria in passerine birds. | avian plumage harbors various pathogens such as feather-degrading bacteria, which have the potential to reduce host fitness. a growing body of evidence suggests that the secretion of the uropygial gland of birds-preen oil-acts as one of the first lines of defence against harmful bacteria. however, previous studies on the antimicrobial impact of preen oil have yielded controversial results. the impact of preen oil on bacterial densities of feathers was experimentally investigated in two passerine ... | 2020 | 31980936 |
| climate change may affect fatal competition between two bird species. | climate warming has altered phenologies of many taxa [1, 2], but the extent differs vastly between [3, 4] and within trophic levels [5-7]. differential adjustment to climate warming within trophic levels may affect coexistence of competing species, because relative phenologies alter facilitative and competitive outcomes [8, 9], but evidence for this is scant [10, 11]. here, we report on two mechanisms through which climate change may affect fatal interactions between two sympatric passerines, th ... | 2019 | 30639109 |
| nest site preference depends on the relative density of conspecifics and heterospecifics in wild birds. | social learning allows animals to eavesdrop on ecologically relevant knowledge of competitors in their environment. this is especially important when selecting a habitat if individuals have relatively little personal information on habitat quality. it is known that birds can use both conspecific and heterospecific information for social learning, but little is known about the relative importance of each information type. if provided with the choice between them, we expected that animals should c ... | 2017 | 29270207 |
| feasibility of sun and magnetic compass mechanisms in avian long-distance migration. | birds use different compass mechanisms based on celestial (stars, sun, skylight polarization pattern) and geomagnetic cues for orientation. yet, much remains to be understood how birds actually use these compass mechanisms on their long-distance migratory journeys. here, we assess in more detail the consequences of using different sun and magnetic compass mechanisms for the resulting bird migration routes during both autumn and spring migration. first, we calculated predicted flight routes to de ... | 2018 | 29992024 |
| testing different forms of regulation of yolk thyroid hormone transfer in pied flycatchers. | hormones transferred from mothers to their offspring are considered a maternal tool to prepare progeny for expected environmental conditions, increasing maternal and offspring fitness. to flexibly influence offspring, mothers should be able to transmit the hormonal signals independent of their own hormonal status. however, the ability to regulate hormone transfer to the next generation is under debate. we studied the transfer of thyroid hormones (ths) to eggs in a bird model. we elevated thyroxi ... | 2020 | 32978314 |
| testing for context-dependent effects of prenatal thyroid hormones on offspring survival and physiology: an experimental temperature manipulation. | maternal effects via hormonal transfer from the mother to the offspring provide a tool to translate environmental cues to the offspring. experimental manipulations of maternally transferred hormones have yielded increasingly contradictory results, which may be explained by differential effects of hormones under different environmental contexts. yet context-dependent effects have rarely been experimentally tested. we therefore studied whether maternally transferred thyroid hormones (ths) exert co ... | 2020 | 32884067 |
| heritability of the extra-pair mating behaviour of the pied flycatcher in western siberia. | males and females take part in extra-pair copulations in most socially monogamous bird species. the mechanisms leading to the frequent occurrence of extra-pair offspring in socially monogamous couples are strongly debated and unresolved, and they are often difficult to distinguish from one another. most hypotheses explaining the evolution of extra-pair reproduction suggest selective and adaptive scenarios for their origination and persistence. is extra-pair paternity a heritable trait? we evalua ... | 2020 | 32821536 |
| electron microscopy study of the central retinal fovea in pied flycatcher: evidence of a mechanism of light energy transmission through the retina. | we present unique ultrastructural data on avian retinal cells. presently and earlier (zueva et al., 2016) we explored distribution of intermediate filaments (ifs) in retinal cells of the pied flycatcher (ficedula hypoleuca, passeriformes, aves) in the central foveolar zone. this retinal zone only contains single and double cone photoreceptors. previously we found that continuous ifs span müller cells (mc) lengthwise from the retinal inner limiting membrane (ilm) layer up to the outer limiting me ... | 2020 | 32566783 |
| carcinogenic and teratogenic status of human population and polychlorinated biphenyls contaminations of soils and biota (european pied flycatcher) in a perm (western ural, russia). | polychlorinated biphenyls (pcbs) are included in the persistent organic pollutants designated by the stockholm convention and are hazardous compounds both for the environment and public health. the aim of this study was to determine the level of environmental pollution of pcbs in the perm, in soil and biota (european pied flycatcher), and to analyze whether its presence was the cause of cancer and congenital malformations in the population. soils in the study area had pcb concentrations of 101.8 ... | 2020 | 32557128 |
| manipulation of prenatal thyroid hormones does not affect growth or physiology in nestling pied flycatchers. | hormones transferred from mothers to their offspring are thought to be a tool for mothers to prepare their progeny for expected environmental conditions, thus increasing fitness. thyroid hormones (ths) are crucial across vertebrates for embryonic and postnatal development and metabolism. yet yolk ths have mostly been ignored in the context of hormone-mediated maternal effects. in addition, the few studies on maternal ths have yielded contrasting results that could be attributed to either species ... | 2020 | 32412834 |
| female oxidative status in relation to calcium availability, metal pollution and offspring development in a wild passerine. | both ca deficiency and metal exposure may affect physiological and nutritional condition of breeding females altering their ability to deposit essential resources (e.g. ca, antioxidants) into the eggs. this effect of the maternal investment into egg quality is not strictly limited to the embryonic period, but may persist after hatching, since nutrient levels in yolks can compromise nestling antioxidant status, growth and fledging success. the goal of this study was to investigate how metal pollu ... | 2020 | 31991347 |
| variation in parasitoidism of protocalliphora azurea (diptera: calliphoridae) by nasonia vitripennis (hymenoptera: pteromalidae) in spain. | parasitoid wasps may act as hyperparasites and sometimes regulate the populations of their hosts by a top-down dynamic. nasonia vitripennis (walker, 1836) is a generalist gregarious parasitoid that parasitizes several host flies, including the blowfly protocalliphora hough, 1899 (diptera, calliphoridae), which in turn parasitizes bird nestlings. nonetheless, the ecological factors underlying n. vitripennis prevalence and parasitoidism intensity on its hosts in natural populations are poorly unde ... | 2020 | 31786698 |
| availability of specific prey types impact pied flycatcher (ficedula hypoleuca) nestling health in a moderately lead contaminated environment in northern sweden. | anthropogenic metal contamination can cause increased stress in exposed organisms, but it can be difficult to disentangle the anthropogenic influence from natural variation in environmental conditions. in the proximity of a closed lead (pb)/zinc (zn) mine in northern sweden, the health effects of pb exposure, essential element (calcium [ca] and zn) uptake, and prey availability and composition were estimated on pied flycatcher (ficedula hypoleuca) nestlings, using hemoglobin (hb) level as a prox ... | 2020 | 31753628 |
| plastic but repeatable: rapid adjustments of mitochondrial function and density during reproduction in a wild bird species. | most of the energy fluxes supporting animal performance flow through mitochondria. hence, inter-individual differences in performance might be rooted in inter-individual variations in mitochondrial function and density. furthermore, because the energy required by an individual often changes across life stages, mitochondrial function and density are also expected to show within-individual variation (i.e. plasticity). no study so far has repeatedly measured mitochondrial function and density in th ... | 2019 | 31718511 |
| evolutionary response to climate change in migratory pied flycatchers. | climate change is rapidly advancing spring phenology [1-3] but at different rates in different species [1, 4]. whether these advances are solely driven by phenotypic plasticity [2, 5] or also involve evolution is hotly debated (e.g., [5-7]). in some species, including avian long-distance migrants, plastic responses to early springs may be constrained by inherited circannual timing programs [8, 9], making evolutionary adjustment the only viable mechanism for keeping pace with shifting phenology [ ... | 2019 | 31668621 |
| impact of continuous predator threat on telomere dynamics in parent and nestling pied flycatchers. | in addition to direct mortality, predators can have indirect effects on prey populations by affecting prey behaviour or physiology. for example, predator presence can increase stress hormone levels, which can have physiological costs. stress exposure accelerates the shortening of telomeres (i.e. the protective caps of chromosomes) and shorter telomeres have been linked to increased mortality risk. however, the effect of perceived predation risk on telomeres is not known. we investigated the effe ... | 2019 | 31612326 |
| maternal food supplementation and perceived predation risk modify egg composition and eggshell traits but not offspring condition. | mothers may vary resource allocation to eggs and embryos, which may affect offspring fitness and prepare them for future environmental conditions. the effects of food availability and predation risk on reproduction have been extensively studied, yet their simultaneous impacts on reproductive investment and offspring early life conditions are still unclear. we experimentally manipulated these key environmental elements using a 2×2 full factorial design in wild, free-living pied flycatchers (ficed ... | 2019 | 31548290 |
| timing manipulations reveal the lack of a causal link across timing of annual-cycle stages in a long-distance migrant. | organisms need to time their annual-cycle stages, like breeding and migration, to occur at the right time of the year. climate change has shifted the timing of annual-cycle stages at different rates, thereby tightening or lifting time constraints of these annual-cycle stages, a rarely studied consequence of climate change. the degree to which these constraints are affected by climate change depends on whether consecutive stages are causally linked (scenario i) or whether the timing of each stage ... | 2019 | 31413104 |
| experimentally flight-impaired females show higher levels of extra-pair paternity in the pied flycatcher ficedula hypoleuca. | there is no consensus yet on the reasons why females engage in extra-pair copulations (epcs). in some species, females have been shown to accrue some indirect benefits, but these effects are not consistent across species and studies. the sexual conflict hypothesis posits that extra-pair paternity (epp) is the result of strong selection for male pursuit of epc without real benefits for females. in order to test this hypothesis, we experimentally reduced wing area (reversibly tying together some p ... | 2019 | 31387473 |
| short-term, but not long-term, increased daytime workload leads to decreased night-time energetics in a free-living song bird. | reproduction is energetically expensive and to obtain sufficient energy, animals can either alter their metabolic system over time to increase energy intake (increased-intake hypothesis) or reallocate energy from maintenance processes (compensation hypothesis). the first hypothesis predicts a positive relationship between basal metabolic rate (bmr) and energy expenditure (dee) because of the higher energy demands of the metabolic system at rest. the second hypothesis predicts a trade-off between ... | 2019 | 31278130 |
| a songbird compensates for wing molt during escape flights by reducing the molt gap and increasing angle of attack. | during molt, birds replace their feathers to retain feather quality and maintain flight performance. however, wing gaps inherent of this process can also reduce flight capacities, which could be detrimental when foraging or escaping predators. still, many bird species will not cease their normal activities when molting. in this study, we investigated whether and how birds adjust their escape flight behavior to compensate for the reduction in performance when flying with wing gaps. using stereosc ... | 2019 | 31085600 |
| repeated stimulation of the pituitary-adrenal axis alters offspring phenotype of a wild passerine. | prolonged stress can have long-lasting effects on an individual's physiology and growth. however, the impact of chronically elevated glucocorticoids on the expression of early antipredator responses is still poorly documented. in this study, i simulated the effect of repeated acute stress on offspring phenotype in free-living pied flycatchers (ficedula hypoleuca) by administering adrenocorticotropic hormone (acth) to nestlings for 6 days. the results showed that frequent induction of stress resp ... | 2019 | 31053648 |
| experimental evidence of non-random nest material selection in pied flycatchers. | nest building is a taxonomically widespread behaviour that consists of the construction of a suitable receptacle with collected materials for the incubation of eggs and sometimes for the raising of offspring. the use of specific nest materials has important fitness consequences for avian parents and offspring because they help to determine the thermal, parasitic and bacterial environment within nests and may also influence parental investment via intraspecific signalling. however, we presently k ... | 2019 | 31014981 |
| elevated oxidative stress in pied flycatcher nestlings of eumelanic foster fathers under low rearing temperatures. | striking variation in melanin coloration within natural populations is likely due to the different fitness outcomes of alternative phenotypes in varying environmental conditions. there are two types of melanin: eumelanins yield blackish hues, whereas pheomelanins yield reddish hues. the production of eumelanins requires low levels of glutathione (gsh), which is the most important intracellular antioxidant, whereas the production of pheomelanins requires high levels of gsh. we investigated the ox ... | 2019 | 30819723 |
| genotype-free estimation of allele frequencies reduces bias and improves demographic inference from radseq data. | restriction-site associated dna sequencing (radseq) facilitates rapid generation of thousands of genetic markers at relatively low cost; however, several sources of error specific to radseq methods often lead to biased estimates of allele frequencies and thereby to erroneous population genetic inference. estimating the distribution of sample allele frequencies without calling genotypes was shown to improve population inference from whole genome sequencing data, but the ability of this approach t ... | 2019 | 30633448 |
| interspecific transfer of parasites following a range-shift in ficedula flycatchers. | human-induced climate change is expected to cause major biotic changes in species distributions and thereby including escalation of novel host-parasite associations. closely related host species that come into secondary contact are especially likely to exchange parasites and pathogens. both the enemy release hypothesis (where invading hosts escape their original parasites) and the novel weapon hypothesis (where invading hosts bring new parasites that have detrimental effects on native hosts) pre ... | 2018 | 30598810 |
| diversity of social-genetic relationships in the socially monogamous pied flycatcher (ficedula hypoleuca) breeding in western siberia. | we explored the genetic background of social interactions in two breeding metapopulations of the pied flycatcher (ficedula hypoleuca) in western siberia. in 2005, we sampled blood from birds breeding in study areas located in the city of tomsk and in a natural forest 13 km southward of tomsk (western siberia, russia). we sampled 30 males, 46 females, 268 nestlings (46 nests) in the urban settlement of pied flycatcher, and 232 males, 250 females, 1,485 nestlings (250 nests) in the woodland plot. ... | 2018 | 30564520 |
| interspecific information on predation risk affects nest site choice in a passerine bird. | breeding site choice constitutes an important part of the species niche. nest predation affects breeding site choice, and has been suggested to drive niche segregation and local coexistence of species. interspecific social information use may, in turn, result in copying or rejection of heterospecific niche characteristics and thus affect realized niche overlap between species. we tested experimentally whether a migratory bird, the pied flycatcher ficedula hypoleuca, collects information about ne ... | 2018 | 30514204 |
| the songs of male pied flycatchers: exploring the legacy of the fathers. | singing is a key element of songbirds' behavioral repertoire, particularly for males, which sing during the breeding season to defend resources against other males and to attract females. different song traits may convey honest information about males' qualities or conditions, which may be used by females to select their mates. traits under strong sexual selection have an important component of additive genetic variation (i.e., the main genetic inheritance from parents), and so relatively high h ... | 2018 | 30083477 |
| difference in plasticity of resting metabolic rate - the proximate explanation to different niche breadth in sympatric ficedula flycatchers. | variation in relative fitness of competing recently formed species across heterogeneous environments promotes coexistence. however, the physiological traits mediating such variation in relative fitness have rarely been identified. resting metabolic rate (rmr) is tightly associated with life history strategies, thermoregulation, diet use, and inhabited latitude and could therefore moderate differences in fitness responses to fluctuations in local environments, particularly when species have adapt ... | 2018 | 29760898 |
| sex-specific associations between telomere dynamics and oxidative status in adult and nestling pied flycatchers. | oxidative stress can contribute to an acceleration of telomere erosion, leading to cellular senescence and aging. increased investment in reproduction is known to accelerate senescence, generally resulting in reduced future reproductive potential and survival. to better understand the role played by oxidative status and telomere dynamics in the conflict between maintenance and reproduction, it is important to determine how these factors are related in parents and their offspring. we investigated ... | 2018 | 29547348 |
| climate change leads to differential shifts in the timing of annual cycle stages in a migratory bird. | shifts in reproductive phenology due to climate change have been well documented in many species but how, within the same species, other annual cycle stages (e.g. moult, migration) shift relative to the timing of breeding has rarely been studied. when stages shift at different rates, the interval between stages may change resulting in overlaps, and as each stage is energetically demanding, these overlaps may have negative fitness consequences. we used long-term data of a population of european p ... | 2018 | 29211325 |
| haemoparasites of the pied flycatcher: inter-population variation in the prevalence and community composition. | the prevalence and community composition of haemoparasites can substantially differ among avian host populations, which may lead to different selection pressures. therefore, information about these parameters is crucial for understanding, e.g. the inter-population variation in host life history traits. here, we molecularly screened a population of a long-distance migrant, the pied flycatcher ficedula hypoleuca, from central poland for the presence of three genera of blood parasites: haemoproteus ... | 2018 | 29113599 |
| evaluating blood and excrement as bioindicators for metal accumulation in birds. | birds are widely used to assess metal contamination in the environment and there are different approaches to determine the exposure level in individuals, some being destructive (collection of soft tissues) and some non-destructive (blood, feathers and excrement). the use of blood to detect internal concentrations of metals is an acknowledged method, but to what extent blood can predict the concentrations in soft tissues has been less well evaluated in wild terrestrial birds. the same is true for ... | 2018 | 29050729 |
| variation of lymphoid activity in the spleen of a migratory bird, the pied flycatcher (ficedula hypoleuca; aves, passeriformes). | the size and microscopic structure of the spleen of the migratory pied flycatcher (ficedula hypoleuca) show marked changes during the reproductive cycle. upon the spring return to their northern breeding sites, the birds have a small spleen with little lymphoid activity and a poorly developed red pulp. during the breeding period the volume of red and white pulp increases, the number and distinctness of lymphoid follicles (germinal centres) in the white pulp increase, and groups of cells with int ... | 1985 | 30016847 |