| kemerovo virus from a migrating common redstart of eurasia. | | 1971 | 4395764 |
| leucocytozoonosis and trypanosomiasis in redstarts in finland. | leucocytozoon spp. and trypanosoma spp. blood parasites in the redstart (phoenicurus phoenicurus) were studied during spring migration 1994 in southern finland (53 individuals) and the breeding season 1992-1994 in northern finland (69). parasite prevalence was higher during the breeding season (48%) than during the migration period (13%), with no age or sex differences in the breeding site birds. in both periods, redstarts were infected by the same blood parasites leucocytozoon shaartusicum (46% ... | 1999 | 10479101 |
| ticks (acari: ixodidae) and spirochetes (spirochaetaceae: spirochaetales) recovered from birds on a georgia barrier island. | from september 1997 through july 1999, 300 individuals and 46 species of birds were mist-netted and screened for ticks and spirochetes on st. catherine's island, liberty county, ga. seventy-six (25%) of the birds were parasitized by a meal intensity of 4.6 ticks. seasonally, more birds were infested with ticks during the summer (50% in 1998, 34% in 1999) than in spring (15% in 1998, 11% in 1999) or fall (21% in 1997, 20% in 1998), mainly because of severe infestations on some birds by immature s ... | 2001 | 11296828 |
| a molecular comparison of plumage and soil bacteria across biogeographic, ecological, and taxonomic scales. | we used molecular methods to determine the microbial community of soil and avian plumage across biogeographic, ecological, and taxonomic scales. a total of 17 soil and 116 feather samples were collected from five avian species across multiple habitat types within one neotropical and one temperate locality. hypotheses regarding patterns of microbial composition relative to acquisition and dispersal of plumage bacteria in the ecosystem were tested by comparing microbial communities within and betw ... | 2007 | 17334855 |
| exploitation of an ancient escape circuit by an avian predator: prey sensitivity to model predator display in the field. | certain insectivorous birds, such as the painted redstart (myioborus pictus), undertake flush pursuit--a characteristic display that elicits an escape reaction by an insect, which the bird then chases in the air and eats. this account describes experiments showing that flush pursuit uses visual displays, which are likely to exploit an ancient neural circuit in dipteran insects, the visual systems of which are well documented as detecting looming stimuli and triggering an escape responses. using ... | 2000 | 11111136 |
| sensory exploitation of prey: manipulation of the initial direction of prey escapes by a conspicuous "rare enemy". | the painted redstart (myioborus pictus) represents a group of non-cryptic predators, the flush pursuers, who visually trigger prey escapes by spreading and pivoting their conspicuously patterned tails and wings. the prey are then chased in aerial pursuits. such an exploitation of prey may be possible because the predation risk from redstarts is smaller than that from the predatory guild of insectivores and their neural pathways are adapted to helping prey avoid common predators rather than "rare ... | 2001 | 11375085 |
| exploitation of an ancient escape circuit by an avian predator: relationships between taxon-specific prey escape circuits and the sensitivity to visual cues from the predator. | the painted redstart myioborus pictus uses visual displays to flush, pursue, and then capture an abundance of brachyceran diptera that are equipped with giant fiber escape circuits. this paper investigates the relationships between features of the giant fiber system, the structure of visual stimuli produced by redstarts and their effectiveness in eliciting escape reactions by flies. the results show that dipterous taxa having large-diameter giant fibers extending short distances from the brain t ... | 2001 | 11964498 |
| habitat-specific sensory-exploitative signals in birds: propensity of dipteran prey to cause evolution of plumage variation in flush-pursuit insectivores. | sensory exploitation occurs when signals trigger behavioral reactions that diminish the receiver's fitness. research in this area focuses on the match between the signal's form and the receiver's sensitivity, but the effect of habitat on interspecific sensory exploitation is rarely addressed. myioborus redstarts use conspicuous wing and tail displays of contrasting black-and-white plumage patches to flush dipteran insects, which are then pursued and captured in flight. previous studies have show ... | 2006 | 17263122 |
| evolutionary significance of geographic variation in a plumage-based foraging adaptation: an experimental test in the slate-throated redstart (myioborus miniatus). | geographic variation in the plumage pattern of birds is widespread but poorly understood, and in very few cases has its evolutionary significance been investigated experimentally. neotropical warblers of the genus myioborus use their contrasting black-and-white plumage to flush insect prey during animated foraging displays. although previous experimental work has demonstrated that white plumage patches are critical to flush-pursuit foraging success, the amount of white in the plumage shows consi ... | 2006 | 16817547 |
| predicting the consequences of carry-over effects for migratory populations. | migratory animals present a unique challenge for predicting population size because they are influenced by events in multiple stages of the annual cycle that are separated by large geographic distances. here, we develop a model that incorporates non-fatal carry-over effects to predict changes in population size and show how this can be integrated with predictive models of habitat loss and deterioration. examples from barn swallows, greater snow geese and american redstarts show how carry-over ef ... | 2006 | 17148350 |
| 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 ... | 2010 | 20002586 |
| genetic evidence for female host-specific races of the common cuckoo. | the common cuckoo cuculus canorus is divided into host-specific races (gentes). females of each race lay a distinctive egg type that tends to match the host's eggs, for instance, brown and spotted for meadow pipit hosts or plain blue for redstart hosts. the puzzle is how these gentes remain distinct. here, we provide genetic evidence that gentes are restricted to female lineages, with cross mating by males maintaining the common cuckoo genetically as one species. we show that there is differenti ... | 2000 | 11001055 |
| a host-race of the cuckoo cuculus canorus with nestlings attuned to the parental alarm calls of the host species. | the common cuckoo has several host-specific races, each with a distinctive egg that tends to match its host's eggs. here, we show that the host-race specializing on reed warblers also has a host-specific nestling adaptation. in playback experiments, the nestling cuckoos responded specifically to the reed warbler's distinctive 'churr' alarm (given when a predator is near the nest), by reducing begging calls (likely to betray their location) and by displaying their orange-red gape (a preparation f ... | 2006 | 16608688 |
| the common redstart as a suitable model to study cuckoo-host coevolution in a unique ecological context. | co-evolutionary arms-races result in spatio-temporally dynamic relationships between interacting species, e.g., brood parasites and their avian hosts. however, majority of avian co-evolutionary studies are limited to "snap-shots" of a single breeding season in an open-nesting host. in a long-term study (11 breeding seasons), we explored a unique system between the brood parasitic common cuckoo (cuculus canorus) and its host, the common redstart (phoenicurus phoenicurus) which is exceptional amon ... | 2016 | 27887566 |
| scale-dependent habitat selection in migratory frugivorous passerines. | frugivorous migrants may select fruit-rich habitats en route to attain high food rewards, yet their stopover behavior may also be shaped by other considerations, such as predation risk. during 1996-2001 we investigated autumn stopover habitat use of three sylvia warblers (sylviids; s. hortensis, s. atricapilla and s. curruca) and three turdidae chats (turdids; cercotrichas galactotes, oenanthe hispanica and phoenicurus phoenicurus) in planted groves of the fruiting tree pistacia atlantica in lah ... | 2004 | 15455207 |
| modeling the flocking propensity of passerine birds in two neotropical habitats. | we examined the importance of mixed-species flock abundance, individual bird home range size, foraging height, and foraging patch characteristics in predicting the propensity for five neotropical passerine bird species (slaty antwren, myrmotherula schisticolor; golden-crowned warbler, basileuterus culicivorus; slate-throated redstart, myioborus miniatus; wilson's warbler, wilsonia pusilla; and black-and-white warbler, mniotilta varia) to forage within flocks, rather than solitarily. we used stud ... | 2007 | 17375332 |
| malarial infections in sedentary and migratory passerine birds in israel: description of new species. | our objective was to investigate the diversity of plasmodium species in birds of the rift valley section in israel. plasmodium merulae corradetti & scanga, 1973 was previously reported in blackbirds (turdus merula linnaeus, 1758), that are resident. we also report and describe three other species and seven new species of plasmodium from migratory birds in the north, and from eilat at the southernmost tip of the jordan valley. new species are: plasmodium lusciniae sp. n., plasmodium alloreticulat ... | 2010 | 22320017 |
| egg colour mimicry in the common cuckoo cuculus canorus as revealed by modelling host retinal function. | some parasite cuckoo species lay eggs that, to the human eye, appear to mimic the appearance of the eggs of their favourite hosts, which hinders discrimination and removal of their eggs by host species. hitherto, perception of cuckoo-host egg mimicry has been estimated based on human vision or spectrophotometry, which does not account for what the receivers' eye (i.e. hosts) actually discriminates. using a discrimination model approach that reproduces host retinal functioning, and museum egg col ... | 2008 | 18595836 |
| correction: can nocturnal flight calls of the migrating songbird, american redstart, encode sexual dimorphism and individual identity? | [this corrects the article doi: 10.1371/journal.pone.0156578.]. | 2017 | 27472288 |
| investigations on infection status with h5 and h7 avian influenza virus in short-distance and long-distance migrant birds in 2001. | the role of migrating birds as potential vectors for avian influenza virus (aiv) was investigated. we captured 543 migrating passerines during their stopover on the island of helgoland (north sea) in spring and autumn 2001. these birds were sampled for avian influenza a viruses (aiv), specifically the subtypes h5 and h7. for virus detection, samples were taken from 1) short-distance migrants, such as chaffinches (fringilla coelebs; n = 131) and song thrushes (turdus philomelos; n = 169); and 2) ... | 2007 | 17494601 |
| no detection of avian influenza a viruses of the subtypes h5 and h7 and isolation of lentogenic avian paramyxovirus serotype 1 in passerine birds during stopover in the year 2001 on the island helgoland (north sea). | a total of 543 migrating passerines were captured during their stopover on the island of helgoland (north sea) in spring and autumn 2001. they were sampled for the detection of avian influenza a viruses (aiv) subtypes h5 and h7, and for avian paramyxoviruses serotype 1 (apmv-1). the goal of the study was to examine the role of migrating birds as potential vectors for these zoonotic viral diseases. for virus detection samples were taken from a) short-distance migrants such as chaffinches (fringil ... | 2005 | 16425631 |
| prevalence of hematozoa in overwintering american redstarts (setophaga ruticilla): no evidence for local transmission. | we examined american redstarts (setophaga ruticilla) for protozoan blood parasites on their wintering grounds to determine whether transmission of these parasites occurs prior to spring migration. a total of 73 blood smears from 37 birds were examined for presence and intensity of infection. thirty-six birds were sampled in the fall, soon after arriving from northern breeding grounds, and the spring prior to departure. two (5%) of the samples collected in the fall were positive for haemoproteus ... | 2004 | 15137497 |
| mites (family trombiculidae) parasitizing birds migrating from africa to europe. | the mechanisms of dissemination of arthropod-borne human and animal pathogens are of considerable interest to the epidemiologist, veterinarian and biologist. birds which are hosts to such pathogens and their arthropod vectors could transport them over long distances during their spring and autumn migratory flights.in april 1961, birds migrating from africa to europe were collected in south-western spain and examined for ectoparasites and antibodies to arboviruses. fully engorged larvae of two sp ... | 1964 | 14267750 |
| q fever in domestic and wild birds. | the authors report on the results of several years' research into the role of domestic and wild birds in the epidemiology and epizootiology of q fever in czechoslovakia. they examined 572 blood specimens taken from domestic birds in an area of endemic q fever and found positive reactions to the complement-fixation test in hens, turkeys, ducks, geese, and pigeons, with hens showing the highest percentage of positive reactions. in addition, the susceptibility of hens to infection with rickettsia b ... | 1956 | 13383368 |
| 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 ... | 2003 | 12760670 |
| postexercise ketosis in night-migrating passerine birds. | this study investigated the postexercise metabolism of six species of free-living, night-migrating passerine birds (european robin, pied flycatcher, wheatear, redstart, blackcap, and garden warbler). the birds were caught during autumn migration out of their nocturnal flight, and their metabolism changed from a fasting, highly active state to a fasting, resting state. concentrations of six plasma metabolites of the fat, carbohydrate, and protein metabolism were measured during up to 10 h of reco ... | 2001 | 11226017 |
| 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 ... | 2017 | 28637857 |
| 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 ... | 2017 | 28515892 |
| 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 ... | 2015 | 26122036 |
| 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 ... | 2014 | 24792820 |
| 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 ... | 2014 | 24517241 |
| 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 ... | 2013 | 23981955 |
| organophosphate pesticide method development and presence of chlorpyrifos in the feet of nearctic-neotropical migratory songbirds from canada that over-winter in central america agricultural areas. | recent modeling analysis suggests that numerous birds may be at risk of acute poisoning in insecticide-treated fields. although the majority of avian field studies on pesticides have focused on treated seed, granule, insect or vegetation (oral exposure) ingestion, dermal exposure is an important exposure route when birds come into contact with deposited pesticides on foliage and other surfaces. some nearctic-neotropical migratory songbirds are likely exposed to pesticides on their non-breeding h ... | 2016 | 26421621 |
| 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 ... | 2013 | 23544426 |
| species interactions and population density mediate the use of social cues for habitat selection. | 1. the perspective that populations and communities are structured by antagonistic interactions among individuals has dominated much of ecology. yet how animals use social information to guide decisions, such as habitat selection, may be influenced by both positive and negative interactions among individuals. recent theory also suggests that the way animals use social information may be substantially influenced by population density, which alters the potential costs and benefits of such behaviou ... | 2007 | 17439476 |
| social information and community dynamics: nontarget effects from simulating social cues for management. | artificially creating social stimuli may be an effective tool for facilitating settlement by rare and/or declining species into suitable habitat. however, the potential consequences for other community members have not been explored and should be considered when evaluating the overall utility of using such management strategies. i report on nontarget, community-wide effects that occurred when manipulating social cues of two competitors that are species of concern in the western united states, th ... | 2008 | 18839770 |
| 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 ... | 2013 | 23433033 |
| 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 ... | 2013 | 23337030 |
| 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 ... | 2012 | 23284852 |
| 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 ... | 2011 | 21872602 |
| 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 ... | 2011 | 21325321 |
| [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 ... | 2010 | 21174351 |
| importation of hyalomma marginatum, vector of crimean-congo haemorrhagic fever virus, into the united kingdom by migratory birds. | hyalomma marginatum ticks are an important vector of crimean-congo haemorrhagic fever virus which can result in a severe and potentially fatal disease in humans. given the continued emergence of clinical cases in eurasia and focalised upsurges of h. marginatum populations in europe, it seemed prudent to assess the potential of this vector species to be introduced into the united kingdom. immature forms of h. marginatum are frequent ectoparasites of passerine birds many of which migrate from afri ... | 2012 | 22300969 |
| winter habitat quality but not long-distance dispersal influences apparent reproductive success in a migratory bird. | long-distance breeding and natal dispersal play central roles in many ecological and evolutionary processes, including gene flow, population dynamics, range expansion, and individual responses to fluctuating biotic and abiotic conditions. however, the relative contribution of long-distance dispersal to these processes depends on the ability of dispersing individuals to successfully reproduce in their new environment. unfortunately, due to the difficulties associated with tracking dispersal in th ... | 2016 | 27349098 |
| hydrogen isotopic variation in migratory bird tissues of known origin: implications for geographic assignment. | continent-wide variation in hydrogen isotopic composition of precipitation is incorporated into animal diets, providing an intrinsic marker of geographic location at the time of tissue growth. feathers from migratory birds are now frequently analyzed for stable-hydrogen isotopes (deltad) to estimate the location of individuals during a preceding molt. using known-origin birds, we tested several assumptions associated with this emerging technique. we examined hydrogen isotopic variation as a func ... | 2007 | 17370093 |
| can nocturnal flight calls of the migrating songbird, american redstart, encode sexual dimorphism and individual identity? | bird species often use flight calls to engage in social behavior, for instance maintain group cohesion and to signal individual identity, kin or social associations, or breeding status of the caller. additional uses also exist, in particular among migrating songbirds for communication during nocturnal migration. however, our understanding of the information that these vocalizations convey is incomplete, especially in nocturnal scenarios. to examine whether information about signaler traits could ... | 2016 | 27284697 |
| climate and density influence annual survival and movement in a migratory songbird. | assessing the drivers of survival across the annual cycle is important for understanding when and how population limitation occurs in migratory animals. density-dependent population regulation can occur during breeding and nonbreeding periods, and large-scale climate cycles can also affect survival throughout the annual cycle via their effects on local weather and vegetation productivity. most studies of survival use mark-recapture techniques to estimate apparent survival, but true survival rate ... | 2015 | 26811763 |
| experimental reduction of winter food decreases body condition and delays migration in a long-distance migratory bird. | many tropical habitats experience pronounced dry seasons, during which arthropod food availability declines, potentially limiting resident and migratory animal populations. in response to declines in food, individuals may attempt to alter their space use to enhance access to food resources, but may be socially constrained from doing so by con- and heterospecifics. if social constraints exist, food declines should result in decreased body condition. in migratory birds, correlational evidence sugg ... | 2015 | 26378315 |
| molecular phylogenetics and biogeography of the neotropical redstarts (myioborus; aves, parulinae). | montane areas in the neotropics are characterized by high diversity and endemism of birds and other groups. the avian genus myioborus (parulinae) is a group of insectivorous warblers, characteristic of cloud forests, that represents one of the few parulinae genera (new world warblers) that has radiated substantially in south america. the genus is distributed throughout most montane regions from the southwestern united states to northern argentina. here, i use mitochondrial sequences from the cyt ... | 2005 | 15935704 |
| ecology. a head start for some redstarts. | | 2004 | 15619587 |
| non-breeding season habitat quality mediates the strength of density-dependence for a migratory bird. | our understanding of when natural populations are regulated during their annual cycle is limited, particularly for migratory species. this information is needed for parametrizing models that can inform management and conservation. here, we use 14 years of data on colour-marked birds to investigate how conspecific density and habitat quality during the tropical non-breeding period interact to affect body condition and apparent annual survival of a long-distance migratory songbird, the american re ... | 2015 | 26136445 |
| habitat features and long-distance dispersal modify the use of social information by a long-distance migratory bird. | the processes by which individuals select breeding sites have important consequences for individual tness as well as population- and community-dynamics. although there is increasing evidence that many animal species use information acquired from conspecics to assess the suitability of potential breeding sites, little is known about how the use of this social information is modified by biotic and abiotic conditions. we used an automated playback experiment to simulate two types of social informat ... | 2015 | 26061822 |
| arrival fat and reproductive performance in a long-distance passerine migrant. | long-distance passerine migrants deposit substantial fat stores to fuel their migratory journey. many of those migratory birds arrive at their northerly breeding grounds with larger fat stores than were necessary to reach their breeding area. both male and female american redstarts ( setophaga ruticilla) arrived to breed in michigan's upper peninsula with fat, and females arrived with more fat than males in 2 out of 3 years. we test the hypothesis that migrants arriving at the breeding grounds w ... | 2003 | 12647139 |
| color expression in experimentally regrown feathers of an overwintering migratory bird: implications for signaling and seasonal interactions. | plumage coloration in birds plays a critical role in communication and can be under selection throughout the annual cycle as a sexual and social signal. however, for migratory birds, little is known about the acquisition and maintenance of colorful plumage during the nonbreeding period. winter habitat could influence the quality of colorful plumage, ultimately carrying over to influence sexual selection and social interactions during the breeding period. in addition to the annual growth of color ... | 2014 | 24834321 |
| experimental and observational studies of seasonal interactions between overlapping life history stages in a migratory bird. | prior to reproduction, migratory animals are at the juxtaposition of three life history stages in which they must finish the non-breeding stage, initiate and complete migration, and prepare for the onset of breeding. however, how these stages interact with one another is not fully understood. we provide evidence that, for migratory birds that begin breeding development prior to departure from non-breeding sites, the level of breeding preparation can drive migration phenology, a critical behavior ... | 2013 | 24128687 |
| the eyes have it: long-distance dispersal by an intraorbital leech parasite of birds. | a leech was found parasitizing the ocular orbit of a common redstart captured during a faunistic survey of antikythira in the aegean sea during the spring migration of 2012. morphological and molecular characterizations placed the leech in the mucous-membrane specific leech family praobdellidae and definitively as the species parapraobdella lineata. this is the first record of any leech parasitizing a passerine bird, phoenicurus phoenicurus , and the first of a praobdellid leech on any avian hos ... | 2013 | 23656566 |
| the effects of experimental irrigation on plant productivity, insect abundance and the non-breeding season performance of a migratory songbird. | migratory bird populations are often limited by food during the non-breeding season. correlative evidence suggests that food abundance on territories varies among years in relation to rainfall, which affects plant productivity and arthropod biomass. at the font hill nature preserve in jamaica, we used an irrigation experiment to test the hypothesis that rainfall affects the condition of wintering american redstarts (setophaga ruticilla) via intermediate effects on plant productivity and arthropo ... | 2013 | 23372825 |
| diurnal and individual variability in the foraging behavior of american redstarts (setophaga ruticilla). | the foraging behavior of american redstarts, setophaga ruticilla (aves: parulidae), was examined from dawn to dusk in the nestling phase of their breeding cycle in a northern hardwoods forest in new hampshire, usa. based on a sample size of nearly 3000 foraging acts, we found that redstarts hawked more and foraged lower at midday than early in the morning, coincident with a statistically significant increase in the abundance of flying insects in the lower strata of the forest at that time of day ... | 1978 | 28309123 |
| deep sympatric mitochondrial divergence without reproductive isolation in the common redstart phoenicurus phoenicurus. | mitochondrial dna usually shows low sequence variation within and high sequence divergence among species, which makes it a useful marker for phylogenetic inference and dna barcoding. a previous study on the common redstart (phoenicurus phoenicurus) revealed two very different mtdna haplogroups (5% k2p distance). this divergence is comparable to that among many sister species; however, both haplogroups coexist and interbreed in europe today. herein, we describe the phylogeographic pattern of thes ... | 2012 | 23301165 |
| winter rainfall predicts phenology in widely separated populations of a migrant songbird. | climate change is affecting behaviour and phenology in many animals. in migratory birds, weather patterns both at breeding and at non-breeding sites can influence the timing of spring migration and breeding. however, variation in responses to weather across a species range has rarely been studied, particularly among populations that may winter in different locations. we used prior knowledge of migratory connectivity to test the influence of weather from predicted non-breeding sites on bird pheno ... | 2013 | 23161154 |
| range-wide effects of breeding- and nonbreeding-season climate on the abundance of a neotropical migrant songbird. | geographic variation in the population dynamics of a species can result from regional variability in climate and how it affects reproduction and survival. identifying such effects for migratory birds requires the integration of population models with knowledge of migratory connectivity between breeding and nonbreeding areas. we used bayesian hierarchical models with 26 years of breeding bird survey data (1982-2007) to investigate the impacts of breeding- and nonbreeding-season climate on abundan ... | 2011 | 21939075 |
| rainfall-induced changes in food availability modify the spring departure programme of a migratory bird. | climatic warming has intensified selection for earlier reproduction in many organisms, but potential constraints imposed by climate change outside the breeding period have received little attention. migratory birds provide an ideal model for exploring such constraints because they face warming temperatures on temperate breeding grounds and declining rainfall on many tropical non-breeding areas. here, we use longitudinal data on spring departure dates of american redstarts (setophaga ruticilla) t ... | 2011 | 21450737 |
| patches of bare ground as a staple commodity for declining ground-foraging insectivorous farmland birds. | conceived to combat widescale biodiversity erosion in farmland, agri-environment schemes have largely failed to deliver their promises despite massive financial support. while several common species have shown to react positively to existing measures, rare species have continued to decline in most european countries. of particular concern is the status of insectivorous farmland birds that forage on the ground. we modelled the foraging habitat preferences of four declining insectivorous bird spec ... | 2010 | 20949083 |
| does stress response predict return rate in a migratory bird species? a study of american redstarts and their non-breeding habitat. | in vertebrates, the adrenocortical stress response activates an emergency life-history stage, which is thought to promote survival by helping individuals escape life-threatening situations. although the adrenocortical stress response promotes many behavioural and physiological changes, it remains unclear whether this stress response actually translates into higher survival in wild vertebrates. we measured the adrenocortical stress response of non-breeding american redstarts (setophaga ruticilla) ... | 2009 | 19605397 |
| non-breeding season events influence sexual selection in a long-distance migratory bird. | the study of sexual selection has traditionally focused on events and behaviours immediately surrounding copulation. in this study, we examine whether carry-over effects from the non-breeding season can influence the process of sexual selection in a long-distance migratory bird, the american redstart (setophaga ruticilla). previous work on american redstarts demonstrated that overwintering in a high-quality habitat influences spring departure dates from the wintering grounds, advances arrival da ... | 2009 | 19203918 |
| circadian flight schedules in night-migrating birds caught on migration. | many species of migratory birds migrate in a series of solitary nocturnal flights. between flights, they stop to rest and refuel for the next segment of their journey. the mechanism controlling this behaviour has long remained elusive. here, we show that wild-caught migratory redstarts (phoenicurus phoenicurus) are consistent in their flight scheduling. an advanced videographic system enabled us to determine the precise timing of flight activity in redstarts caught at a northern european stopove ... | 2008 | 18765352 |
| improved estimates of certainty in stable-isotope-based methods for tracking migratory animals. | the use of stable-hydrogen isotopes (deltad) has become a common tool for estimating geographic patterns of movement in migratory animals. this method relies on broad and relatively predictable geographic patterning in deltad values of precipitation, but these patterns are not estimated without error. in addition, deltad measurements are relatively imprecise, particularly for organic tissue. most models for estimating geographic locations have ignored these sources of error. common modeling appr ... | 2008 | 18488615 |
| phylogeography of a widespread north american migratory songbird (setophaga ruticilla). | genetic analyses for many widespread north american species have revealed significant east-west differentiation, indicating that many survived through the pleistocene in 2 glacial refugia-1 in the eastern and 1 in the western part of the continent. it remains unclear, however, whether other areas may have served as important glacial refugia. moreover, many such species exhibit widespread genetic similarity within eastern and western regions because of recent expansion from small refugial populat ... | 2010 | 18468988 |
| natal dispersal driven by environmental conditions interacting across the annual cycle of a migratory songbird. | natal dispersal, the process through which immature individuals permanently depart their natal area in search of new sites, is integral to the ecology and evolution of animals. insights about the underlying causes of natal dispersal arise mainly from research on species whose short dispersal distances or restricted distributions make them relatively easy to track. however, for small migratory animals, the causes of natal dispersal remain poorly understood because individuals are nearly impossibl ... | 2008 | 18287030 |
| optimal conservation of migratory species. | migratory animals comprise a significant portion of biodiversity worldwide with annual investment for their conservation exceeding several billion dollars. designing effective conservation plans presents enormous challenges. migratory species are influenced by multiple events across land and sea-regions that are often separated by thousands of kilometres and span international borders. to date, conservation strategies for migratory species fail to take into account how migratory animals are spat ... | 2007 | 17710150 |
| continent-wide variation in feather colour of a migratory songbird in relation to body condition and moulting locality. | understanding the causes of variation in feather colour in free-living migratory birds has been challenging owing to our inability to track individuals during the moulting period when colours are acquired. using stable-hydrogen isotopes to estimate moulting locality, we show that the carotenoid-based yellow-orange colour of american redstart (setophaga ruticilla) tail feathers sampled on the wintering grounds in central america and the caribbean is related to the location where feathers were gro ... | 2007 | 17443954 |
| social cues facilitate habitat selection: american redstarts establish breeding territories in response to song. | for migratory songbirds nesting in northern temperate forests, a short breeding season demands that males rapidly establish territories. because critical insect and vegetation resources are unavailable during spring arrival, we suggest that conspecifics serve as settlement cues for males new to a local population. to test conspecific attraction, we conducted playback experiments with american redstarts setophaga ruticilla. experimental results demonstrate that song playbacks strongly attract con ... | 2006 | 17148397 |
| assessing habitat quality for a migratory songbird wintering in natural and agricultural habitats. | as tropical forests are cleared, a greater proportion of migratory songbirds are forced to winter in agricultural and disturbed habitats, which, if poorer in quality than natural forests, could contribute to population declines. we compared demographic indicators of habitat quality for a focal species, the american redstart (setophaga ruticilla), wintering in jamaican citrus orchards and shade coffee plantations with those in four natural habitats: mangrove, coastal scrub, coastal palm, and dry ... | 2006 | 17002761 |
| sampling variability and estimates of density dependence: a composite-likelihood approach. | it is well known that sampling variability, if not properly taken into account, affects various ecologically important analyses. statistical inference for stochastic population dynamics models is difficult when, in addition to the process error, there is also sampling error. the standard maximum-likelihood approach suffers from large computational burden. in this paper, i discuss an application of the composite-likelihood method for estimation of the parameters of the gompertz model in the prese ... | 2006 | 16634310 |
| reproductive effort, molting latitude, and feather color in a migratory songbird. | toward the end of the breeding season, migratory songbirds face crucial tradeoffs between the timing of reproduction, molt, and migration. using stable hydrogen isotopes, we show that male american redstarts investing in high levels of reproduction late in the season adopt a unique strategy of combining molt and migration. tail feathers molted during migration also reflect less orange-red light, indicating reduced carotenoid concentration. thus, we show how reproduction in a migratory animal can ... | 2004 | 15618516 |
| tropical winter habitat limits reproductive success on the temperate breeding grounds in a migratory bird. | identifying the factors that control population dynamics in migratory animals has been constrained by our inability to track individuals throughout the annual cycle. using stable carbon isotopes, we show that the reproductive success of a long-distance migratory bird is influenced by the quality of habitat located thousands of kilometres away on tropical wintering grounds. for male american redstarts (setophaga ruticilla), winter habitat quality influenced arrival date on the breeding grounds, w ... | 2004 | 15002772 |
| inter-annual variation in american redstart (setophaga ruticilla) plumage colour is associated with rainfall and temperature during moult: an 11-year study. | carotenoid-based colouration plays an important role in sexual signaling in animals as an honest indicator of individual quality during mate choice and competitive interactions. however, few studies have examined how natural variation in weather conditions influences inter-annual variation in the expression of ornamentation, potentially through affecting the dietary availability of carotenoids. in this study, we examine variation in the expression of carotenoid-based plumage colouration in relat ... | 2015 | 25433695 |
| are there different requirements for trace elements in eumelanin- and pheomelanin-based color production? a case study of two passerine species. | melanin is the most common pigment in animal integuments including bird plumage. it has been shown that several trace elements may play roles in the production and signaling function of melanin-colored plumage. we investigated coloration and content of various metal elements in the rectrices of two insectivorous passerines, common redstarts (phoenicurus phoenicurus) and blackcaps (sylvia atricapilla), which have eumelanin- and pheomelanin-based coloration, respectively. we hypothesized that 1) t ... | 2014 | 24905646 |
| linking winter and summer events in a migratory bird by using stable-carbon isotopes | for migratory birds, early arrival and physical condition on the breeding grounds are important determinants of reproductive success and fitness. differences in arrival times often exceed a month, and later arriving individuals are often in poorer condition. habitat-specific isotopic signatures indicate that the quality of winter habitats occupied by american redstarts (setophaga ruticilla) determines their physical condition and spring departure dates, which in turn result in variable arrival s ... | 1998 | 9836637 |
| corticosterone levels as indicators of habitat quality: effects of habitat segregation in a migratory bird during the non-breeding season. | during the non-breeding season, many species of territorial migratory birds exhibit a non-random pattern of habitat distribution, with males and females occupying different habitats. in this study, we examined possible physiological consequences arising from such habitat segregation in one migrant passerine species, the american redstart (setophaga ruticilla), on its non-breeding grounds in jamaica, west indies. for 2 years, we measured concentrations of corticosterone, at the time of capture (b ... | 1998 | 28308538 |
| adaptive significance of delayed attainment of plumage in male american redstarts: tests of two hypotheses. | | 1981 | 28563145 |
| alkhurma hemorrhagic fever virus rna in hyalomma rufipes ticks infesting migratory birds, europe and asia minor. | alkhurma hemorrhagic fever virus rna was detected in immature hyalomma rufipes ticks infesting northward migratory birds caught in the north mediterranean basin. this finding suggests a role for birds in the ecology of the alkhurma hemorrhagic fever virus and a potential mechanism for dissemination to novel regions. increased surveillance is warranted. | 2018 | 29664386 |
| animal migration research takes wing. | in the beginning there was great confusion about animal migration. aristotle, noting that the types of birds around him changed with the seasons, concluded that summer redstarts turned into robins at the onset of winter, and that garden warblers became blackcaps [1]. others thought that birds disappear in winter because they hibernate submerged in mud. in a case of art decidedly not imitating life, a 16th century illustration accompanying the writings of swedish archbishop olaus magnus showed a ... | 2018 | 30205070 |
| migratory birds as disseminators of ticks and the tick-borne pathogens borrelia bacteria and tick-borne encephalitis (tbe) virus: a seasonal study at ottenby bird observatory in south-eastern sweden. | birds can act as reservoirs of tick-borne pathogens and can also disperse pathogen-containing ticks to both nearby and remote localities. the aims of this study were to estimate tick infestation patterns on migratory birds and the prevalence of different borrelia species and tick-borne encephalitis virus (tbev) in ticks removed from birds in south-eastern sweden. | 2020 | 33272317 |
| three babesia species in ixodes ricinus ticks from migratory birds in sweden. | migratory birds can cross geographical and environmental barriers and are thereby able to facilitate transmission of tick-borne pathogens both as carriers of infected ticks and as reservoirs of pathogenic microorganisms. ixodes ricinus is one of the most abundant tick species in the northern hemisphere and a main vector of several babesia species, some which pose a potential threat to human and animal health. at present only two cases of overt babesiosis in humans have so far been reported in sw ... | 2021 | 33794970 |
| redstarts, phoenicurus phoenicurus, can orient in a true-zero magnetic field. | i tested the migratory orientation of redstarts in a true-zero magnetic field to elucidate the importance to this species of access to either magnetic or celestial cues. i also tested the validity of the assumption on which all funnel experiments are based: that what we observe in an orientation funnel reflects what the bird would do if actually migrating. in a set of funnel experiments, i tested 47 night-migrating redstarts caught during their first autumn migration. each bird was tested once u ... | 1998 | 9632514 |
| screening for multiple tick-borne pathogens in ixodes ricinus ticks from birds in denmark during spring and autumn migration seasons. | presently, it is uncertain to what extent seasonal migrating birds contribute to the introduction of ticks and tick-associated pathogens in denmark. to quantify this phenomenon, we captured birds during the spring and autumn migration at three field sites in denmark and screened them for ticks. bird-derived ticks were identified to tick species and screened for 37 tick-borne pathogens using real-time pcr. overall, 807 birds, representing 44 bird species, were captured and examined for ticks duri ... | 2019 | 30709658 |
| a quasi-experimental approach using telemetry to assess migration-strategy-specific differences in the decision-making processes at stopover. | migrant birds travel between their breeding areas and wintering grounds by alternating energetically and physiologically demanding flights with periods of rest and fuelling, so-called stopovers. an important intrinsic factor influencing the decision to resume migration is the amount of energy stores available for the next flight. correlative studies with free-flying birds and experimental studies with caged birds have shown that the amount of energy stores affects the day-to-day, within-day and ... | 2020 | 32641125 |
| fitting different visual models to behavioral patterns of parasitic egg rejection along a natural egg color gradient in a cavity-nesting host species. | avian brood parasites lay their eggs in other birds' nests, and hosts can mitigate the fitness cost of raising unrelated offspring by rejecting parasitic eggs. a visually-based cognitive mechanism often thought to be used by hosts to discriminate the foreign egg is to compare it against the hosts' own eggshell by size, shape, maculation, and/or ground coloration (i.e., absolute chromatic contrast). however, hosts may instead discriminate eggs based on their colors along a scale of natural avian ... | 2020 | 31958715 |
| rearing a virulent common cuckoo is not extra costly for its only cavity-nesting host. | virulent brood parasites refrain from arduous parental care, often kill host progeny and inflict rearing costs upon their hosts. quantifying the magnitude of such costs across the whole period of care (from incubation through to parasite fledgling independence) is essential for understanding the selection pressures on hosts to evolve antiparasitic defences. despite the central importance of such costs for our understanding of coevolutionary dynamics, they have not yet been comprehensively quanti ... | 2018 | 30355712 |
| interspecific competition between resident and wintering birds: experimental evidence and consequences of coexistence. | the contribution of interspecific competition to structuring population and community dynamics remains controversial and poorly tested. specifically, interspecific competition has long been thought to influence the structure of migrant-resident bird communities in winter, yet experimental evidence remains elusive. the arrival of billions of songbirds into neotropical habitats, where they co-exist with residents, provides a unique opportunity to assess interspecific competition and its consequenc ... | 2020 | 32981090 |