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Certain populations of long-distance migratory birds are suffering declines, which may be attributed to effects of climate change. In this article, we have analysed a long-term (1991-2015) data set on a pied flycatcher Ficedula hypoleuca population breeding in nest-boxes in a Mediterranean montane oak forest, exploring the trends in population size due to changes in nestling recruitment, female survival and female immigration. We have related these changes in population parameters to local climate, winter NAO index and to breeding density. During the last 25 yr the population has declined by half, mainly in association with a decrease in nestling mass and structural size which had repercussions on the probability of nestling recruitment to the population. Lower local nestling recruitment in certain years was linked to lower female immigration rate in the same years. On the other hand, the local survival of females remained stable throughout the study period. Laying date and breeding success were negatively affected by local temperatures while breeding, recruitment rate likewise by minimum temperature prior to breeding in April. As minimum April temperatures have increased across the study period, this may have affected recruitment and immigration rates negatively. On the other hand, tarsus length and body mass of nestlings were positively associated with winter NAO index, pointing to more global climatic links. Moreover, there was also a negative temporal trend in body mass of adults, implying increasingly difficult conditions for breeding. Declining recruit production in the study area could be attributed to a mismatch between the timing of arrival and breeding in the population, and the peak of food availability in this area. [ABSTRACT FROM AUTHOR]

Social selection is expected to favour the evolution of female aggressive defence of nesting resources in cavity-nesting birds, which may be also mediated by testosterone (T) levels. Male T levels could express male dominance and thereby territorial safety for female partners and thereby reduce their need for aggressive defence. Here, we explored the role of T levels in female-female competition in a songbird, the pied flycatcher Ficedula hypoleuca. In an experiment with female decoys placed close to the nestbox at the end of laying, we explored if female aggressiveness is related to their own T level or to mate T level. T levels of males and females were measured in the middle of the nestling period. Mean female aggressiveness towards decoys in three presentations was estimated through proximity to the decoy and number of attacks by females, two variables which were positively associated. Aggressiveness by female nest owners to female decoys was negatively related to male T level but unrelated to own T level. There was no assortative mating with respect to T level. Female aggressiveness is more strongly related to the hormonal status of mates than to their own. [ABSTRACT FROM AUTHOR]

We compared the in vitro bacterial degradability of the white patch and melanized area of primary feathers of breeding male and female Pied Flycatchers Ficedula hypo-leuca and related this variation to laying date, brood size and brood mass. Bacterial degradability of male and female white feather patches, but not of melanized areas, was positively correlated with laying date. Male Pied Flycatchers showed a positive correlation between bacterial degradability of the white patch, though not of the melanized patch, and brood size and brood mass. Feather degradability appears to be negatively related to individual quality and positively related to reproductive effort. [ABSTRACT FROM AUTHOR]

Nesting holes are a scarce resource for obligated cavity-nesting birds and an important selective force for the evolution of aggressive female behaviours, which may be mediated by testosterone (T) levels. It is known that during periods of intense intrasexual competition such as initial breeding stages, females are highly aggressive towards intruding females. Here, we studied the implications of T levels for female-female competition by comparing levels of aggressiveness towards simulated female intruders (decoys) in two populations of the pied flycatcher ( Ficedula hypoleuca) with a marked difference in breeding density. To this end, we exposed free-living females to simulated territorial intrusions during 30 min when nest construction was almost complete. T levels of females were measured at the beginning of incubation under the assumption that they are positively associated with T levels during nest building. We also related aggressiveness to T levels in both populations. Furthermore, we aimed at detecting whether variation of T levels may explain female incubation attendance. Females showed higher T levels in the populations where pied flycatchers were exposed to a higher likelihood of conspecific interactions (high breeding density) than in the population with low breeding density. Female territorial presence, vigilance at the nest box and proximity to decoys were negatively related to circulating T levels in the high-density population, but not in the low-density population. Differences in T levels between populations did not result in differences in female incubation attendance, but T levels were negatively related to the incubation attendance in females from the population showing high T levels. In our populations, T levels in females prior to laying reflect the need to defend nesting cavities which is higher at high breeding density and in subdominant females. High T levels are costly in terms of incubation attendance. [ABSTRACT FROM AUTHOR]

Despite many studies of how male characteristics affect paternity in predominantly monogamous birds, relatively little attention has been given to the traits of females that may influence extra-pair paternity ( EPP). However, the occurrence of EPP may be the result of behavioural interactions in which both male and female traits are important for determining the outcome. If EPP is driven mainly by female choice of extra-pair sires, older, more experienced or larger females would be better able to evade mate guarding tactics and more capable of selecting extra-pair mates and resisting unwanted suitors. This would be especially noticeable in females paired with unattractive mates. On the other hand, if EPP is driven mainly by male pursuit, we should expect that young, inexperienced or small females would be more exposed to coercive male approaches independently of social mate traits. In a study of an Iberian population of the pied flycatcher Ficedula hypoleuca, we found that EPP affected 38% of the broods and 17% of the nestlings. These values are relatively high, allowing a relatively large number of affected within-pair mates to be included. We found that EPP is related to both female and male traits although not to any interaction between male and female traits. EPP was higher at nests tended by both younger and short-winged females and by browner males. Older females may be more experienced and dominant while long-winged females may be faster fliers, these traits enabling them to avoid extra-pair copulations, while brown males are less aggressive towards male intruders. In our study population, EPP appears to be caused by male pursuit, which in some cases may overwhelm female attempts to avoid extra-pair copulations and their social partner's ability to prevent them. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Zoology is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nest-dwelling ectoparasites may result in costs for nestlings of cavity nesters in terms of compromised growth and condition before fledging. The reduction or elimination of nest ectoparasites to study their effects on avian hosts can be conducted through physical methods such as heat-treatment or through chemical methods using insecticides. Pyrethroids are the most frequently used of the latter, although some studies have shown that they may compromise the development and future survival of birds. In this study conducted in central Spain we analysed the differences between a group of fumigated Pied Flycatcher Ficedula hypoleuca nests and a heat-treated group, both rendered ectoparasitefree by these treatments. We also compared these ectoparasite-free nests with a control group with natural ectoparasite loads. Our aim was to test the possible effects of a pyrethroid- based insecticide on reproductive success, parental care behaviours and body condition of adult females and nestlings. We also determined the effects of treatment on a biochemical biomarker, the total glutathione (tGSH) level, involved in detoxification of xenobiotics and considered the most important intracellular antioxidant. Although behavioural variables were not affected by treatment, results showed lighter 3-day-old chicks and shorter tarsi and wings in nestlings shortly before fledging in fumigated nests, together with depletion of tGSH levels in both females and nestlings. Fumigation with pyrethroids in ectoparasite load reduction experiments may introduce undesired systematic variability associated with toxicity, leading to underestimation of the effects of ectoparasites on avian hosts. [ABSTRACT FROM AUTHOR]

Among the cellular pathways conferring protection against oxidative stress, a key role is played by heat-shock proteins, especially HSP70. It has been proposed that blue egg colouration in certain birds, which is related to the deposition of the pigment biliverdin, should be related to basic antioxidant processes in the laying female given the strong antioxidant role of biliverdin. If HSP70 levels express antioxidant defences a higher allocation of the pigment to the clutch could induce a higher response by other components of the antioxidant system like HSP70. In a field study of a breeding population of pied flycatchers Ficedula hypoleuca, a species laying blue-green eggs, we measured spectrometrically the colouration of all eggs and collected blood samples of incubating females one week after clutch completion. We estimated female condition, plasma antioxidant capacity and level of HSP70 in blood cells. HSP70 level was positively related to plasma antioxidant capacity indicating that HSP70 is involved in responses to oxidative stress. Variation in HSP70 level was in good part explained by mean egg blue-green chroma of the clutch when controlling for plasma antioxidant capacity. Results suggest that intensity of eggshell blue colouration in this population is related to a basic system involved in protection against oxidative stress. [ABSTRACT FROM AUTHOR]

The article cites a research study that examines how the presence of generalist ectoparasites in nests affect hole-nesting birds. The study is carried on three sympatric avian cavity-nesters, namely Pied Flycatchers Ficedula hypokuca, Blue Tits Cyanistes caeruleus and Nuthatches Sitta europaea. It examines whether interspecific differences in their nest size is responsible for differences in prevalence and abundance of generalist ectoparasites.

The impact of feather-degrading bacilli on feathers depends on the presence or absence of melanin. In vitro studies have demonstrated that unmelanized (white) feathers are more degradable by bacteria than melanized (dark) ones. However, no previous study has looked at the possible effect of feather-degrading bacilli on the occurrence of patterns of unmelanized patches on otherwise melanized feathers. The pied flycatcher Ficedula hypoleuca Pallas, 1764 is a sexually dimorphic passerine with white wing bands consisting of unmelanized patches on dark flight feathers. These patches are considered to be a sexually selected trait in Ficedula flycatchers, especially in males, where the patches are more conspicuous (larger and possibly whiter) than in females. Using in vitro tests of feather bacterial degradation, we compared the degradability of unmelanized and melanized areas of the same feather for 127 primaries collected from the same number of individuals in a population breeding in central Spain (58 males and 69 females). In addition, we also looked for sex differences in feather degradability. Based on honest signalling theory and on the fact that there is stronger sexual selection for males to signal feather quality than in females, we predicted that unmelanized areas should be more degradable by bacteria than melanized ones within the same feather, and that these unmelanized areas should also be more degradable in males than in females. We confirmed both predictions. Microstructural differences between cross-section dimensions of unmelanized and melanized barbs, but not differences in the density of barbs within unmelanized and melanized areas of feathers in males and females, could partly explain differences in degradability. This is the first study to show differences in bacterial degradability among markings on the same feather and among unmelanized feather patches between males and females as predicted by sexual selection theory. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105, 409-419. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Field Ornithology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article discusses results of a study of the blue-green colouration of the Pied Flycatcher eggshell in Spain. The study methodology is discussed, including observation of the egg colour at the moment of oviposition, onset and end of incubation. Using a spectrophotometer, the study showed significant fading of egg colours during the period, with further blue-green colouration fade from six to 23 months after incubation for unhatched eggs.The study suggested that temporal changes should be taken into account on egg colouration. Also noted was the significant interaction between the incubation measurement and the type of measurement.

The article explores the impact of nest construction on the nestling growth of birds. The authors conducted the study with a focus on the Pied Flycatcher Ficedula hypoleuca and they aim to possible effects of duration and the materials used in nest construction on overall reproductive success. The study involved placing stored complete nests as a replacement for the original nests built by the birds. They found that on the fourth day of observation that female provisioning effort was doubled in experimental nests, which in turn affected their parental care in the coming days.

Environmental factors may strongly affect avian-biting fly interactions in different ways because insects are heterothermic organisms that depend greatly on environmental variables to activate their metabolism and behaviour. We studied the effects of weather on both blackfly (Simuliidae) and biting midge Culicoides (Ceratopogonidae) abundance in nests of three passerine species: blue tits Cyanistes caeruleus, great tits Parus major and pied flycatchers Ficedula hypoleuca, breeding in the same area. We controlled for different host-related factors (hatching date, brood size and host species). Blackfly abundance was negatively related to minimum temperature. In addition, blackfly and biting midge abundances were negatively affected by wind speed measured at 07.00 h, but blackfly abundance was positively associated to wind speed at 18.00 h. We found higher blackfly and biting midge abundances in nests with larger broods breeding later in the season, and significantly higher biting midge abundance in pied flycatcher nests as compared to tit nests. These results represent, to our knowledge, the first report of both environmental and host-related effects on haematophagous fly abundance in the nests of wild hole-nesting birds. [ABSTRACT FROM AUTHOR]

The pied flycatcher is one of the most phenotypically variable bird species in Europe. The geographic variation in phenotypes has often been attributed to spatial variation in selection regimes that is associated with the presence or absence of the congeneric collared flycatcher. Spatial variation in phenotypes could however also be generated by spatially restricted gene flow and genetic drift. We examined the genetic population structure of pied flycatchers across the breeding range and applied the phenotypic QST ( PST)– FST approach to detect indirect signals of divergent selection on dorsal plumage colouration in pied flycatcher males. Allelic frequencies at neutral markers were found to significantly differ among populations breeding in central and southern Europe whereas northerly breeding pied flycatchers were found to be one apparently panmictic group of individuals. Pairwise differences between phenotypic ( PST) and neutral genetic distances ( FST) were positively correlated after removing the most differentiated Spanish and Swiss populations from the analysis, suggesting that genetic drift may have contributed to the observed phenotypic differentiation in some parts of the pied flycatcher breeding range. Differentiation in dorsal plumage colouration however greatly exceeded that observed at neutral genetic markers, which indicates that the observed pattern of phenotypic differentiation is unlikely to be solely maintained by restricted gene flow and genetic drift. [ABSTRACT FROM AUTHOR]

It has been proposed that blue–green egg colouration in certain avian species has evolved as a signal of female and egg quality to males, affecting their investment in the brood according to the differential allocation scenario. A recent experiment has successfully manipulated male investment by placing dummy eggs simulating the extremes in the blue–green natural reflectance. Here we have substituted one egg in certain pied flycatcher clutches with a single deep-blue (blue) or light-blue (pale) dummy egg and used other clutches as controls. Blue dummy eggs reflected more in the blue–green part of the spectrum than natural and pale dummy eggs, which were similar in reflectance. Nestlings in nests with one blue dummy egg during laying and incubation attained a significantly higher mass and condition than those in nests with one pale dummy egg or in control broods, when controlling for phenology, brood size and blue–green chroma of the clutch. Only a shift in parental investment can have induced this highly significant effect. Preference for deeply coloured clutches associated with high-quality females and their maternal effects may explain stimulation by a single supernormal stimulus emanating from multiple objects like clutches. [ABSTRACT FROM AUTHOR]

Female ornamentation has received little attention in studies of sexual selection. Traditionally, female ornaments have been explained as a genetically correlated response to selection in males. However, recent findings suggest that female ornaments may be adaptive. Southern populations of Pied Flycatchers Ficedula hypoleuca are suited for studies of female ornamentation because, in addition to the white wing patch, some females also express the white forehead patch characteristic of males. We thus addressed the associations of these two ornaments with female age and with some health and breeding parameters in a Spanish population of Pied Flycatchers. Female ornament expression was not associated with haemoparasite prevalences, clutch size or parental provisioning effort. However, females expressing the white forehead patch raised more fledglings, and females with larger wing patches bred earlier, had higher number of hatchlings and showed increased levels of total serum immunoglobulins. Thus, these two unrelated epigamic ornaments may indicate some aspects of female quality. Further experimental studies could test the possibility that these plumage traits might function as signals to the males or might be used during female–female aggressive encounters in competition for nest-sites and mates. [ABSTRACT FROM AUTHOR]

A recent hypothesis posits that the bright colours of many avian eggs may act like signals of female genetic quality or condition to males in species with biparental care, inducing them to work harder for their offspring. We measured the colour of blue eggs of pied flycatchers Ficedula hypoleuca in Central Spain with a spectrophotometer on the day of laying, and also quantified the provisioning effort by males and females during the last days of the nestling period. Both chromaticity coordinates in the CIELAB colour space (blue to yellow, green to red) showed significant associations with male provisioning rates, explaining more than 20% of variation in male parental effort. Male provisioning rates were positively correlated with nestling condition, thereby potentially contributing to female fitness. This evidence is only tentative until experimental confirmation, but suggests that males are affected by the colour of their mates’ eggs, a possibility not considered hitherto in the study of sexual selection. [ABSTRACT FROM AUTHOR]

Studies the association between reproductive efforts and blood parasites of breeding pied flycatcher. Prevalence of the blood parasite infections; Accounts on the components of the immune system; Reduction of the energetic costs of flight.

Ecological immunology posits a trade-off between parental effort and immunocompetence underlying the cost of reproduction. The moult-breeding overlap observed in several bird species represents a conflict in resource allocation between two energy-demanding processes. Moult processes have been associated with enlargements of immune system organs. In the present study. we measured simultaneously daily energy expenditure (DEE) and the T-cell-dependent immune response of pied flycatchers, Ficedula hypoleuca, caring for grown nestlings. We used the doubly labelled water technique and the phytohaemagglutinin (PHA) injection assay on both males and females, while recording provisioning rates and moult scores. DEE and the PHA response were negatively correlated for females, but not for males. A significantly higher proportion of males than females initiated moult. Provisioning rates were strongly correlated with DEE for females but only for non-moulting males. The DEE of moulting males was marginally correlated with moult score. For moulting males, there was a marginally significant positive correlation between moult score and immune response. The trade-off between DEE and immunity for females could underlie the cost of reproduction. However, the moult-breeding overlap found in males may offset this trade-off, thereby reducing the implications of immunosuppression for parental survival. [ABSTRACT FROM AUTHOR]

We manipulated parental work load without changing brood size in a population of pied flycatchers Ficedula hypoleuca by removing two primaries (7 and 9) from each wing of females, thus reducing wing area and increasing flight costs. At other nests, we offered supplementary food in the form of live mealworms (10–20 g daily from hatching) to reduce brood demand and thus parental foraging costs. Other nests were left as controls. The daily energy expenditure of females feeding 12-day-old nestlings was measured with doubly labelled water D2 18O. Females in both treatments expended the same amount of energy, fed at the same rate and had similar body masses to birds in the control group. No effect of treatment on male mass and feeding effort was detected. More nestlings, however, died in nests of handicapped females. Nestlings of handicapped females had significantly lower body mass and haematocrit values than nestlings in food-supplemented nests, with nestlings in control nests occupying an intermediate position. The effects of both treatments on nestling mass, haematocrit values and mortality rates were only noticeable in nests infested with mites. Maternal energy expenditure is apparently constrained and offspring pay the costs imposed by reduced provisioning rate or increased demand caused by ectoparasites, while receiving benefits when food supply improves. The presumption that avian reproductive costs derive from changes in a flexible energy output may not be met in many cases. [ABSTRACT FROM AUTHOR]

Abstract: Due to the reduced conspicuousness of female signals, their evolution has traditionally been interpreted as a by-product of sexual or natural selection in males. Recent studies have argued that they may be the result of sexual or social selection acting on females. Here, we explored the role of the white wing patch during the incubation period in female-female competition contests in a migratory cavity-nesting songbird, the pied flycatcher Ficedula hypoleuca. At this stage, female investment is crucial for offspring survival, while competition among females for nest cavities is still operating. We experimentally performed an extreme reduction of signaling capacity by covering the wing patch with dark paint in a group of females and compared their incubation attendance and social interaction patterns (vigilance and aggression at the nest as defense variables) during simulated territorial intrusion tests with female decoys, with those of an unmanipulated group of females. Tests were performed both before and after the manipulation. We hypothesized that these patches constitute signals of social dominance in female-female interactions that allow them to maintain high levels of incubation attendance by reducing the need for vigilance. We found a marked decrease in incubation attendance in experimental females after manipulation, a change that was not found in the control group. Moreover, vigilance decreased in the control group after the manipulation, a change not detected in manipulated females. No effects on aggressive nest defense were found. Female wing ornamental traits would act as a badge of status in social interactions allowing more intense incubation and reduced vigilance. Implications of social interactions on incubation patterns should be incorporated in future studies.Significance statement: Animals can transmit information to the others through different traits. Ornamental signals have been proposed as status indicators in social interactions in birds in many studies. Although some of them concern their function and evolution in females, only a few have been focused on their role during incubation. Our experimental study suggests that the female’s white wing patch in pied flycatchers acts as a badge of dominance status in social encounters. Thus, dominant females may enforce respect from competitors through signaling, thereby being able to reduce vigilance at the nest with positive effects on incubation efficiency. Implications of social status for incubation patterns should be considered in future studies as an additional factor modulating this crucial parental activity. [ABSTRACT FROM AUTHOR]

Presents a study which examined between blood parasites and reproductive success of female Pied Flycatchers breeding in central Spain during the springs of 1998 and 1999. Effect of parasites on host reproduction; Information on the blood sampling procedure; Statistical procedures; Results and discussion.