| spring migratory birds (aves) extend the northern occurrence of blacklegged tick (acari:ixodidae). | birds that had migrated northward across lake superior were captured upon reaching landfall at thunder cape (48 degrees 18' n, 88 degrees 56' w) at the southwestern tip of the sibley peninsula, northwestern ontario, from 9 may to 9 june 1995. twenty-one of 530 birds examined (6 of 55 species) had a total of 34 ticks; 1 blue jay, cyanocitta cristata, had a northern fowl mite, ornithonyssus sylviarum (canestrini & fanzago). four blacklegged tick, ixodes scapularis say, larvae were found on an amer ... | 1996 | 8699451 |
| characterization of microsatellite dna loci for a neotropical migrant songbird, the swainson's thrush (catharus ustulatus) | | 1999 | 10564463 |
| interspecific variability of prevalence in blood parasites of adult passerine birds during the breeding season in alaska. | blood parasite prevalence based on microscopic examination of stained blood smears was determined in adults of 11 passerine bird species sampled during their breeding season (may and june 1997-98) in interior alaska (usa). these species included primarily nearctic migratory species such as the dark-eyed junco (junco hyemalis) and neotropical migratory species such as the blackpoll warbler (dendroica striata), alder flycatcher (empidonax alnorum), swainson's thrush (catharus ustulatus), northern ... | 2001 | 11272501 |
| 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 stable-isotope approach to delineate geographical catchment areas of avian migration monitoring stations in north america. | migration monitoring stations (mmss) were established to provide information on population trends of north american passerines. however, apart from inferring general origins of birds, there has been no way to delineate geographical catchment areas sampled by mmss. the ability to resolve mms catchment areas would greatly enhance our ability to link and constrain population declines to specific geographical areas and thereby focus conservation efforts. here, we utilize stable-hydrogen (delta d) an ... | 2001 | 11355202 |
| birds disperse ixodid (acari: ixodidae) and borrelia burgdorferi-infected ticks in canada. | a total of 152 ixodid ticks (acari: ixodidae) consisting of nine species was collected from 82 passerine birds (33 species) in 14 locations in canada from 1996 to 2000. the lyme disease spirochete borrelia burgdorferi johnson, schmidt, hyde, steigerwaldt & brenner was cultured from the nymph of a blacklegged tick, ixodes scapularis say, that had been removed from a common yellowthroat, geothlypis trichas l., from bon portage island, nova scotia. as a result of bird movement, a nymphal i. scapula ... | 2001 | 11476328 |
| not as the crow flies: a historical explanation for circuitous migration in swainson's thrush (catharus ustulatus). | many migratory songbirds follow circuitous migratory routes instead of taking the shortest path between overwintering and breeding areas. here, we study the migration patterns in swainson's thrush (catharus ustulatus), a neartic-neotropical migrant songbird, using molecular genetic approaches. this species is presently separated into genetically distinct coastal and continental populations that diverged during the late pleistocene (as indicated by molecular dating), yet appear to have retained a ... | 2002 | 12079661 |
| seasonal variation of infestation by ectoparasitic chigger mite larvae (acarina: trombiculidae) on resident and migratory birds in coffee agroecosystems of chiapas, mexico. | parasitism is not well documented for birds found in tropical habitats. long-distance migratory birds may face additional risks to an already hazardous journey when infected. this study explores the ecology of an ectoparasite infestation in chiapas, mexico. during a mist-netting project in 2 different coffee management systems, chigger mites (acarina: trombiculidae), ectoparasitic during the larval stage, were found on both resident and migratory birds. using a rapid assessment protocol, it was ... | 2005 | 16539008 |
| modeling movement of west nile virus in the western hemisphere. | we modeled west nile virus (wnv) movement rates and patterns based on a migratory bird agent (the swainson's thrush) and a resident bird agent (the house sparrow), and compared the results of these models with actual movement data to investigate the likelihood that the pattern of wnv outbreaks observed in the new world was consistent with migrant bird-mediated spread, as reported from the old world. we found that, contrary to old world patterns, wnv activity in the western hemisphere does not se ... | 2006 | 16796510 |
| divergence in mating signals correlates with ecological variation in the migratory songbird, swainson's thrush (catharus ustulatus). | song divergence among populations of passerine birds is recognized as a potentially important premating isolation mechanism and may represent the first step in speciation. because song divergence may be influenced by an array of acoustic, ecological, and genetic factors, the study of its origin requires a multifaceted approach. here we describe the relationship between acoustic, neutral genetic and ecological variation in five populations of the swainson's thrush: two from coastal temperate rain ... | 2006 | 16968261 |
| genetic, morphological, and ecological characterization of a hybrid zone that spans a migratory divide. | this study characterizes a hybrid zone that spans a migratory divide between subspecies of the swainson's thrush (catharus ustulatus), a long distance migratory songbird, in the coast mountains of british columbia. to assess the potential for a barrier to gene flow between the subspecies, i: (1) analyzed the shape and width of genetic and morphological clines relative to estimates of dispersal distance, (2) assessed the ratio of parental to hybrid genotypes across the hybrid zone, (3) estimated ... | 2008 | 18039327 |
| widespread and structured distributions of blood parasite haplotypes across a migratory divide of the swainson's thrush (catharus ustulatus). | we examined the phylogenetic distribution of cytochrome b haplotypes of the avian blood parasite genera haemoproteus and plasmodium across the migratory divide of the swainson's thrush (catharus ustulatus) in british columbia, canada. from 87 host individuals, we identified 8 parasite haplotypes; 4 of plasmodium and 4 of haemoproteus. six haplotypes were novel; 1 haemoproteus haplotype was identical to h. majoris found in the blue tit (parus caeruleus) in sweden, and another halotype was identic ... | 2007 | 18314697 |
| pointed wings, low wingloading and calm air reduce migratory flight costs in songbirds. | migratory bird, bat and insect species tend to have more pointed wings than non-migrants. pointed wings and low wingloading, or body mass divided by wing area, are thought to reduce energy consumption during long-distance flight, but these hypotheses have never been directly tested. furthermore, it is not clear how the atmospheric conditions migrants encounter while aloft affect their energy use; without such information, we cannot accurately predict migratory species' response(s) to climate cha ... | 2008 | 18478072 |
| comparative phylogenetic histories of two louse genera found on catharus thrushes and other birds. | the louse genera brueelia (ischnocera) and myrsidea (amblycera) are broadly codistributed on songbirds (passeriformes), but differ in a variety of life history characteristics. we used mitochondrial and nuclear dna sequences to assess levels of genetic divergence and reconstruct phylogenies of these 2 genera, focusing especially on catharus thrushes in north america. we then qualitatively compared the phylogenies and levels of divergence within these 2 genera of codistributed parasites. neither ... | 2009 | 18821823 |
| mapping the risk of avian influenza in wild birds in the us. | avian influenza virus (aiv) is an important public health issue because pandemic influenza viruses in people have contained genes from viruses that infect birds. the h5 and h7 aiv subtypes have periodically mutated from low pathogenicity to high pathogenicity form. analysis of the geographic distribution of aiv can identify areas where reassortment events might occur and how high pathogenicity influenza might travel if it enters wild bird populations in the us. modelling the number of aiv cases ... | 2010 | 20573228 |
| detection of lyme disease spirochete, borrelia burgdorferi sensu lato, including three novel genotypes in ticks (acari: ixodidae) collected from songbirds (passeriformes) across canada. | lyme disease is reported across canada, but pinpointing the source of infection has been problematic. in this three-year, bird-tick-pathogen study (2004-2006), 366 ticks representing 12 species were collected from 151 songbirds (31 passerine species/subspecies) at 16 locations canada-wide. of the 167 ticks/pools tested, 19 (11.4%) were infected with borrelia burgdorferi sensu lato (s.l.). sequencing of the rrf-rrl intergenic spacer gene revealed four borrelia genotypes: b. burgdorferi sensu stri ... | 2010 | 20618658 |
| lead exposure and poisoning of songbirds using the coeur d'alene river basin, idaho. | previous studies have found widespread pb poisoning of waterfowl in the coeur d'alene river basin in northern idaho, usa, which has been contaminated by mining and smelting activities. we studied the exposure of ground-feeding songbirds to pb, sampling 204 american robins (turdus migratorius), song sparrows (melospiza melodia), and swainson's thrushes (catharus ustulatus) throughout the basin. these songbirds had mean blood pb concentrations (mg/kg, dry weight) of less than 0.19 at a reference a ... | 2011 | 21538831 |
| assessment of risks to ground-feeding songbirds from lead in the coeur d'alene basin, idaho. | previous assessment of ecological risks within the coeur d'alene basin identified lead as a key risk driver for ground-feeding songbirds. as this conclusion was based almost exclusively on literature data, its strength was determined to range from low to moderate. with the support of the u.s. environmental protection agency (usepa), the u.s. fish and wildlife service collected site-specific data to address the uncertainty associated with lead risks to songbirds. these data, plus those from the p ... | 2011 | 21793201 |
| Widespread dispersal of Borrelia burgdorferi-infected ticks collected from songbirds across Canada. | Abstract Millions of Lyme disease vector ticks are dispersed annually by songbirds across Canada, but often overlooked as the source of infection. For clarity on vector distribution, we sampled 481 ticks (12 species and 3 undetermined ticks) from 211 songbirds (42 species/subspecies) nationwide. Using PCR, 52 (29.5%) of 176 Ixodes ticks tested were positive for the Lyme disease spirochete, Borrelia burgdorferi s.l. Immature blacklegged ticks, Ixodes scapularis, collected from infested songbird ... | 2011 | 21864130 |
| flight at low ambient humidity increases protein catabolism in migratory birds. | although fat is the primary fuel for migratory flight in birds, protein is also used. catabolism of tissue protein yields five times as much water per kilojoule as fat, and so one proposed function of protein catabolism is to maintain water balance during nonstop flights. to test the protein-for-water hypothesis, we flew swainson's thrushes (catharus ustulatus) in a climatic wind tunnel under high- and low-humidity conditions at 18°c for up to 5 hours. flight under dry conditions increased the r ... | 2011 | 21903811 |
| mites of the subfamily harpirhynchinae (acariformes: harpirhynchidae) from north american birds. | three new harpirhynchid species of the subfamily harpirhynchinae (acariformes: harpirhynchidae) are described from north american birds: harpyrhynchoides aegolius sp. n. from aegolius acadicus (strigiformes: strigidae), harpyrhynchoides accipiter sp. n. from accipiter striatus (accipitriformes: accipitridae), and neharpyrhynchus icterus sp. n. from icterus galbula (passeriformes: icteridae). three species are recorded from new hosts from north america for the first time: harpyrhynchoides trachea ... | 2013 | 23802444 |
| lipid and water depletion in migrating passerines following passage over the gulf of mexico. | lipid depletion is currently believed to be the primary factor limiting flight duration of migrating birds in north america, while the influence of water loss is thought to be small. three migrating species of passerines, wood thrush (hylocichla mustelina), swainson's thrush (catharus ustulatus), and summer tanager (piranga rubra) were captured during the 1993 spring migration just after crossing the gulf of mexico and examined for lipid and water depletion. the redwinged blackbird (agelaius pho ... | 1996 | 28307151 |
| genomic islands of divergence or opportunities for introgression? | in animals, introgression between species is often perceived as the breakdown of reproductive isolating mechanisms, but gene flow between incipient species can also represent a source for potentially beneficial alleles. recently, genome-wide datasets have revealed clusters of differentiated loci ('genomic islands of divergence') that are thought to play a role in reproductive isolation and therefore have reduced gene flow. we use simulations to further examine the evolutionary forces that shape ... | 2017 | 28275143 |
| seasonal gene expression in a migratory songbird. | the annual migration of a bird can involve thousands of kilometres of nonstop flight, requiring accurately timed seasonal changes in physiology and behaviour. understanding the molecular mechanisms controlling this endogenous programme can provide functional and evolutionary insights into the circannual biological clock and the potential of migratory species to adapt to changing environments. under naturally timed photoperiod conditions, we maintained captive swainson's thrushes (catharus ustula ... | 2016 | 27747949 |
| genomic analysis of a migratory divide reveals candidate genes for migration and implicates selective sweeps in generating islands of differentiation. | differential gene flow, reductions in diversity following linked selection and/or features of the genome can structure patterns of genomic differentiation during the process of speciation. possible sources of reproductive isolation are well studied between coastal and inland subspecies groups of swainson's thrushes, with differences in seasonal migratory behaviour likely playing a key role in reducing hybrid fitness. we assembled and annotated a draft reference genome for this species and genera ... | 2015 | 25808860 |
| a role for migration-linked genes and genomic islands in divergence of a songbird. | next-generation sequencing has made it possible to begin asking questions about the process of divergence at the level of the genome. for example, recently, there has been a debate around the role of 'genomic islands of divergence' (i.e. blocks of outlier loci) in facilitating the process of speciation-with-gene-flow. the swainson's thrush, catharus ustulatus, is a migratory songbird with two genetically distinct subspecies that differ in a number of traits known to be involved in reproductive i ... | 2014 | 24954641 |
| north american transmission of hemosporidian parasites in the swainson's thrush (catharus ustulatus), a migratory songbird. | the geographic structuring of parasite communities across the range of a single host species can illuminate patterns of host-population connectivity. to determine the location of parasite transmission in a neotropical migrant bird species, we sampled adult and hatch-year (hy) birds across the breeding and wintering range of the swainson's thrush (swth), an abundant passerine with a migratory divide. we examined the phylogenetic relationships among cytochrome b lineages of the avian blood parasit ... | 2013 | 23030456 |
| dramatic intraspecific differences in migratory routes, stopover sites and wintering areas, revealed using light-level geolocators. | migratory divides are contact zones between breeding populations that use divergent migratory routes and have been described in a variety of species. these divides are of major importance to evolution, ecology and conservation but have been identified using limited band recovery data and/or indirect methods. data from band recoveries and mitochondrial haplotypes suggested that inland and coastal swainson's thrushes (catharus ustulatus) form a migratory divide in western north america. we attache ... | 2012 | 23015629 |
| differences in timing of migration and response to sexual signalling drive asymmetric hybridization across a migratory divide. | ecological traits and sexual signals may both contribute to the process of ecological speciation. here we investigate the roles of an ecological trait, seasonal migratory behaviour and a sexual trait, song, in restricting or directing gene flow across a migratory divide in the swainson's thrush (catharus ustulatus). we show that short-distance migratory ecotypes wintering in central america arrive earlier at the breeding grounds than long-distance migratory ecotypes wintering primarily in south ... | 2012 | 22747896 |
| linking breeding and wintering grounds of neotropical migrant songbirds using stable hydrogen isotopic analysis of feathers. | recent studies have shown that stable hydrogen isotope ratios (δd) in the tissues of animals often correlate with δd of local precipitation. here we examined the relationship between δd in feathers and growing season precipitation for neotropical migrant songbirds breeding over a continent-wide isotopic gradient. δd values were determined on feathers of 140 individuals of 6 species of wild insectivorous forest songbirds (setophaga ruticilla, empidonax minimus, vermivora peregrinus, catharus ustu ... | 1996 | 28307604 |
| fruit production, migrant bird visitation, and seed dispersal of guarea glabra in panama. | the relationship between bird visitation and the size of the available fruit crop was studied at an understory tree (guarea glabra vahl, meliaceae) in the tropical wet forest of barro colorado island, panama canal zone. twelve resident species and seven north american migrant species fed on the bright orange arilloids (seeds with arils), which were not depleted during the normal fruiting period. the number of individual visitors, the number of visiting species, and the number of seeds removed in ... | 1979 | 28309435 |
| breeding dispersal by birds in a dynamic urban ecosystem. | changes in land cover during urbanization profoundly affect the diversity of bird communities, but the demographic mechanisms affecting diversity are poorly known. we advance such understanding by documenting how urbanization influences breeding dispersal-the annual movement of territorial adults-of six songbird species in the seattle, wa, usa metropolitan area. we color-banded adults and mapped the centers of their annual breeding activities from 2000-2010 to obtain 504 consecutive movements by ... | 2016 | 28030559 |
| fat, weather, and date affect migratory songbirds' departure decisions, routes, and time it takes to cross the gulf of mexico. | approximately two thirds of migratory songbirds in eastern north america negotiate the gulf of mexico (gom), where inclement weather coupled with no refueling or resting opportunities can be lethal. however, decisions made when navigating such features and their consequences remain largely unknown due to technological limitations of tracking small animals over large areas. we used automated radio telemetry to track three songbird species (red-eyed vireo, swainson's thrush, wood thrush) from coas ... | 2015 | 26578793 |
| measurement of glomerular filtration rate during flight in a migratory bird using a single bolus injection of fitc-inulin. | during migration, passerine birds typically complete a series of multi-hour flights, each followed by a period of stopover. during flight, rates of respiratory water loss are high, yet these birds show no signs of dehydration after flights. during stopover, birds become hyperphagic to replenish fat reserves, often consuming food with high water content, such as fruit. thus migratory birds seem to face an osmoregulatory challenge; they must reduce water losses during flight but retain the ability ... | 2013 | 23884146 |
| new feather mites of the genus <i>amerodectes</i> valim and hernandes (acariformes: proctophyllodidae) from passerines (aves: passeriformes) in georgia, usa. | eight new species of the feather mite genus amerodectes valim and hernandes, 2010 (proctophyllodidae: pterodectinae) are described from passerines (aves: passeriformes) in georgia, usa: amerodectes cathari sp. n. from catharus ustulatus (nuttall) (turdidae), a. haemorhous sp. n. from haemorhous mexicanus (muller, pls) (fringillidae), a. helmitheros sp. n. from helmitheros vermivorum (gmelin) (parulidae), a. hribari sp. n. from geothlypis trichas (linnaeus) (parulidae), a. hylocichlae sp. n. from ... | 2017 | 29245629 |
| detection of babesia odocoilei in ixodes scapularis ticks collected from songbirds in ontario and quebec, canada. | songbirds widely disperse ticks that carry a diversity of pathogens, some of which are pathogenic to humans. among ticks commonly removed from songbirds, the blacklegged tick, ixodes scapularis, can harbor any combination of nine zoonotic pathogens, including babesia species. from may through september 2019, a total 157 ticks were collected from 93 songbirds of 29 species in the canadian provinces of ontario and québec. pcr testing for the 18s gene of babesia species detected babesia odocoilei i ... | 2020 | 32987727 |
| mercury exposure in songbird communities along an elevational gradient on whiteface mountain, adirondack park (new york, usa). | mercury (hg) is a potent neurotoxin that biomagnifies within food webs. adverse effects have been documented for avian species related to exposure of elevated hg levels. high elevation, boreal forests generally receive higher atmospheric hg deposition and regional studies have subsequently identified elevated blood hg concentrations in songbird species inhabiting these montane habitats. the overall goal of this study was to investigate spatial and seasonal hg exposure patterns in songbird specie ... | 2020 | 32232628 |
| correlates of bird collisions with buildings across three north american countries. | collisions with buildings cause up to 1 billion bird fatalities annually in the united states and canada. however, efforts to reduce collisions would benefit from studies conducted at large spatial scales across multiple study sites with standardized methods and consideration of species- and life-history-related variation and correlates of collisions. we addressed these research needs through coordinated collection of data on bird collisions with buildings at sites in the united states (35), can ... | 2020 | 32537779 |
| earlier and slower or later and faster: spring migration pace linked to departure time in a neotropical migrant songbird. | migratory birds travel vast distances and the timing of migratory flights can affect survival and the ability to reproduce. for neotropical migrant songbirds, early spring departure from wintering sites, early arrival to the breeding grounds and higher reproductive success have been related to the use of suitable habitats and environmental conditions during the non-breeding season. however, how migratory strategies are shaped by winter habitat choice is largely unknown due to the general inabili ... | 2020 | 32989739 |
| migration tracking reveals geographic variation in the vulnerability of a nearctic-neotropical migrant bird. | we compared the vulnerability of a nearctic-neotropical migrant (swainson's thrush, catharus ustulatus) for three geographically-defined breeding populations in california by linking breeding and wintering regions, estimating migration distances, and quantifying relative forest loss. using data from light-level geolocator and gps tags, we found that breeding birds from the relatively robust coastal population in the san francisco bay area wintered predominantly in western mexico (n = 18), wherea ... | 2020 | 32218483 |
| patterns of blood mercury variation in two long-distance migratory thrushes on mount mansfield, vermont. | we investigated mercury (hg) blood concentrations in bicknell's thrush (catharus bicknelli) and swainson's thrush (c. ustulatus), congeneric long-distance migratory songbirds, from 2000-2017 at a montane forest site in north-central vermont. we analyzed variation in blood hg of both species using mixed-effects models, incorporating atmospheric wet hg deposition data from a nearby sampling location. although hg deposition varied among years and seasonally, we detected no temporal trend in either ... | 2020 | 31520201 |
| the role of humidity and metabolic status on lean mass catabolism in migratory swainson's thrushes (catharus ustulatus). | migratory birds use protein as a fuel source during flight, but the mechanisms and benefits of protein catabolism during migration are poorly understood. the tissue-specific turnover rate hypothesis proposes that lean mass loss depends solely on the constitutive rate of protein degradation for a given tissue, and is therefore independent of metabolic rate or environmental stimuli. however, it has been demonstrated that environmental stressors such as humidity affect the rate of lean mass catabol ... | 2019 | 31455196 |
| estimating apparent survival of songbirds crossing the gulf of mexico during autumn migration. | many migratory bird species are declining, and the migratory period may limit populations because of the risk in traversing large geographical features during passage. using automated radio-telemetry, we tracked 139 swainson's thrushes (catharus ustulatus) departing coastal alabama, usa and crossing the gulf of mexico to arrive in the yucatan peninsula, mexico during autumn. we estimated apparent survival and examined how extrinsic (weather variables and day of year) and intrinsic (fat load, sex ... | 2018 | 30355710 |
| ectoparasitism by chigger mite larvae (acari: trombiculidae) in a wintering population of catharus ustulatus (turdidae) in southeastern peru. | we document chigger mite (acari: trombiculidae) ectoparasitic infestation (prevalence and intensity) on a population of catharus ustulatus (turdidae) wintering at a site (pad a) in southeastern peru undergoing development for natural gas exploration. we compare prevalence (i.e., the proportion of individuals infested by chigger mites) and intensity (i.e., the average number of larvae and larvae clusters in infested individuals) at forest edge (<100 m) and interior (>100 m) from pad a because var ... | 2018 | 29420130 |
| sex-specific hypothalamic-pituitary-gonadal axis sensitivity in migrating songbirds. | in seasonally migratory species, the overlap between the migratory and breeding life history stages is a balance between the physiological and behavioral requirements of each stage. previous studies investigating the degree to which songbirds prepare for breeding during spring migration have focused on either circulating hormone levels or direct measures of gonadal recrudescence. in this study, we evaluated the phenology of breeding preparation in a long-distance migratory songbird, the swainson ... | 2018 | 29128250 |
| comparative analysis of sars-cov-2 and its receptor ace2 with evolutionarily related coronaviruses. | the pandemic covid-19 is caused by the severe acute respiratory syndrome coronavirus 2 (sars-cov-2) and it is spreading very rapidly worldwide. to date, the origin and intermediate hosts of sars-cov-2 remain unclear. in this study, we conducted comparative analysis among sars-cov-2 and non-sars-cov-2 coronavirus strains to elucidate their phylogenetic relationships. we found: 1, the sars-cov-2 strains analyzed could be divided into 3 clades with regional aggregation; 2, the non-sars-cov-2 common ... | 2020 | 33186121 |