Publications

TitleAbstractYear
Filter
PMID
Filter
cutaneous trematode collyriclum faba in wild birds in the central european carpathians.the occurrence of cutaneous trematode collyriclum faba in wild birds was monitored in the central european carpathians from 1996 to 2001. a total of 5,414 birds, representing 86 species, was examined. collyriclum faba was found at 7 sites (5 in slovakia, 1 in poland, and 1 in the czech republic), and prevalences at the sites varied from 1 to 16%. ten species of passerine birds were infected: blackcap (sylvia atricapilla) (16 positive/622 tested, 2% prevalence), black redstart (phoenicurus ochrur ...200312760670
testosterone affects song modulation during simulated territorial intrusions in male black redstarts (phoenicurus ochruros).although it has been suggested that testosterone plays an important role in resource allocation for competitive behavior, details of the interplay between testosterone, territorial aggression and signal plasticity are largely unknown. therefore, we investigated if testosterone acts specifically on signals that communicate the motivation or ability of individuals to engage in competitive situations in a natural context. we studied the black redstart, a territorial songbird species, during two dif ...201223284852
associated and disassociated patterns in hormones, song, behavior and brain receptor expression between life-cycle stages in male black redstarts, phoenicurus ochruros.testosterone has been suggested to be involved in the regulation of male territorial behavior. for example, seasonal peaks in testosterone typically coincide with periods of intense competition between males for territories and mating partners. however, some species also express territorial behavior outside a breeding context when testosterone levels are low and, thus, the degree to which testosterone facilitates territorial behavior in these species is not well understood. we studied territoria ...201323337030
life-history and hormonal control of aggression in black redstarts: blocking testosterone does not decrease territorial aggression, but changes the emphasis of vocal behaviours during simulated territorial intrusions.many studies in behavioural endocrinology attempt to link territorial aggression with testosterone, but the exact relationship between testosterone and territorial behaviour is still unclear and may depend on the ecology of a species. the degree to which testosterone facilitates territorial behaviour is particularly little understood in species that defend territories during breeding and outside the breeding season, when plasma levels of testosterone are low. here we suggest that species that de ...201323433033
description of the puparium of protocalliphora nourtevai (insecta: diptera: calliphoridae).avian blowflies are obligatory blood-sucking parasite larvae that typically pupariate in bird nests. the empty puparia are diagnostically important, as they are usually the only evidence for the presence of these parasites in nests. compared to the nearctic region, very little is known about puparia of palearctic species. here, we provide the first description of puparia of protocalliphora nourtevai from nests of 2 bird species, namely, phoenicurus phoenicurus and phoenicurus ochruros from finla ...201323544426
experimental induction of social instability during early breeding does not alter testosterone levels in male black redstarts, a socially monogamous songbird.testosterone plays an important role in territorial behavior of many male vertebrates and the challenge hypothesis has been suggested to explain differences in testosterone concentrations between males. for socially monogamous birds, the challenge hypothesis predicts that testosterone should increase during male-male interactions. to test this, simulated territorial intrusion (sti) experiments have been conducted, but only about a third of all bird species investigated so far show the expected i ...201323981955
parental care, loss of paternity and circulating levels of testosterone and corticosterone in a socially monogamous song bird.in biparental birds testosterone levels of males are typically high during the mating phase and decrease during the parental phase. testosterone implants may enhance mating behaviors, increase the likelihood of males to engage in extra-pair mating behavior and may reduce paternal care. thus, sex steroids such as testosterone influence reproductive behaviors. little is known, however, as to whether the more subtle differences in physiological concentrations of testosterone that occur between indi ...201424517241
the number of life-history stages does not influence the androgen responsiveness to male-male interactions: sedentary and migratory black redstarts (phoenicurus ochruros) do not elevate testosterone in response to simulated territorial intrusions.high plasma levels of testosterone at the beginning of the breeding season adjust male physiology for mating and promote territorial behavior in birds. conversely intra-sexual competition may elicit a temporary increase in circulating testosterone. male black redstarts (phoenicurus ochruros) from migratory populations show the expected increase in baseline testosterone during early breeding, but circulating testosterone levels do not change in response to male-male interactions. because sedentar ...201424792820
does a short-term increase in testosterone affect the intensity or persistence of territorial aggression? - an approach using an individual's hormonal reactive scope to study hormonal effects on behavior.in this study, we describe an approach based on an individual's hormonal reactive scope to study short-term effects of hormones on behavior. the control of territorial aggression has been traditionally linked to testosterone. males of some vertebrate species show an increase in testosterone during territorial interactions and implantation studies suggest that such an increase in testosterone enhances the intensity and persistence of aggression. here, we tested whether a short-term maximum releas ...201526122036
timing and body condition of dichromatic black redstarts during autumn migration.individual variation in postjuvenile molt in male black redstart is pronounced with about 90% of young males retaining female-like coloration (cairei plumage type) and about 10% acquiring adult male-like feathers (paradoxus plumage type). we examined whether autumn migration timing and body condition differed between individuals of the two plumage types. we used the data of 10,977 black redstarts captured during autumn at a ringing site in northern switzerland where a protocol to record plumage ...201728515892
acute peaks of testosterone suppress paternal care: evidence from individual hormonal reaction norms.a long-standing tenet of evolutionary endocrinology states that testosterone mediates the life-history trade-off between mating and paternal care. however, the support for a role of testosterone in suppressing paternal care is mixed: implantation studies in birds suggest that high-level testosterone implants suppress paternal care, but circulating levels of testosterone and paternal care are typically not correlated. because any trade-off in real life must be realized with hormone levels that ar ...201728637857
comparative phylogeography of five avian species: implications for pleistocene evolutionary history in the qinghai-tibetan plateau.pleistocene climate fluctuations have shaped the patterns of genetic diversity observed in extant species. in contrast to europe and north america where the effects of recent glacial cycles on genetic diversity have been well studied, the genetic legacy of the pleistocene for the qinghai-tibetan (tibetan) plateau, a region where glaciation was not synchronous with the north hemisphere ice sheet maxima, remains poorly understood. here, we compared the phylogeographical patterns of five avian spec ...201020002586
extension of the avian host range of collyriclosis in europe.we describe cases of collyriclosis in apodiform and passeriform birds in portugal, switzerland, and germany. we extend the host range of collyriculm faba to include apodiform birds ( apus apus , apus melba , and apus pallidus ) and the passerine sitta europaea (eurasian nuthatch). infections varied in severity from an incidental finding to severe debilitation and death. the infection route remains unclear with the apparent absence from germany, portugal, and switzerland of the first intermediate ...201728099076
simulating winning in the wild--the behavioral and hormonal response of black redstarts to single and repeated territorial challenges of high and low intensity.in many vertebrates testosterone increases during aggressive interactions and the surges in this hormone may be responsible for the winner effect. so far studies on this relationship have been done in captivity only, because simulating a winning situation for a territory owner in the field is difficult. however, an increasing number of studies show that territorial aggression is not necessarily accompanied by elevated testosterone after a single simulated territorial intrusion (sti) and therefor ...201121872602
ignoring the challenge? male black redstarts (phoenicurus ochruros) do not increase testosterone levels during territorial conflicts but they do so in response to gonadotropin-releasing hormone.competition elevates plasma testosterone in a wide variety of vertebrates, including humans. the 'challenge hypothesis' proposes that seasonal peaks in testosterone during breeding are caused by social challenges from other males. however, during experimentally induced male-male conflicts, testosterone increases only in a minority of songbird species tested so far. why is this so? comparative evidence suggests that species with a short breeding season may not elevate testosterone levels during t ...201121325321
[temporal stability in song dialects of black redstarts (phoenicurus ochruros rufiventris) in menyuan, qinghai province].bird song dialects provide a useful model for the study of cultural evolution and its interactions with genetic evolution. by comparing song dialects over an 8-year span in the black redstarts (phoenicurus ochruros rufiventris) of haibei station (37(0)29'n, 101(0)28'e, 3, 200 m a.s.l.) in menyuan county, qinghai province,this study examined the temporal stability of the birds'song dialects. songs of black redstarts were recorded from mid-april to late may in 2001 by uher-cr 210 tape recorder wit ...201021174351
Displaying items 1 - 16 of 16