| 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 |
| serologic evidence for west nile virus infection in birds in staten island, new york, after an outbreak in 2000. | after an outbreak of west nile virus (wnv) infections in people, horses, and wildlife in staten island, ny, during the summer of 2000, we surveyed the bird population of the island for evidence of infection. neutralizing antibodies were detected in 59 of 257 (23.0%) resident birds and none of 96 transient (migrating) birds sampled in early october. species with the greatest seroprevalence were northern cardinal (cardinalis cardinalis) (69.2%) and rock dove (columba livia) (54.5%). house sparrows ... | 2001 | 12653147 |
| zinc and lead poisoning in wild birds in the tri-state mining district (oklahoma, kansas, and missouri). | the tri-state mining district (oklahoma, kansas, and missouri) is contaminated with pb, cd, and zn from mining, milling and smelting. metals have been dispersed heterogeneously throughout the district in the form of milled mine waste ("chat"), as flotation tailings and from smelters as aerial deposition or slag. this study was conducted to determine if the habitat has been contaminated to the extent that the assessment populations of wild birds are exposed to toxic concentrations of metals. amer ... | 2005 | 15657812 |
| west nile virus epizootiology in the southeastern united states, 2001. | we investigated mosquito and bird involvement in west nile virus (wnv) transmission in july 2001 in jefferson county, fl, and lowndes county, ga. we detected 16 wnv-infected pools from culex quinquefasciatus, cx. salinarius, cx. nigripalpus, and culiseta melanura. in florida, 11% of 353 bird sera neutralized wnv. antibody prevalence was greatest in northern cardinal (cardinalis cardinalis, 75%), northern mockingbird (mimus polyglottus, 50%), common ground-dove (columbina passerina, 25%), common ... | 2005 | 15815153 |
| reservoir competence of native north american birds for the lyme disease spirochete, borrelia burgdorfieri. | reservoir competence for the lyme disease spirochete, borrelia burgdorferi, was tested for six species of native north american birds: american robin, gray catbird, brown thrasher, eastern towhee, song sparrow, and northern cardinal. wild birds collected by mist netting on fire island, ny, were held in a field laboratory in cages over water and locally collected larval ticks were placed on the birds, harvested from the water after engorgement, and tested for infection by direct fluorescentantibo ... | 2005 | 15962798 |
| avian hosts for west nile virus in st. tammany parish, louisiana, 2002. | west nile virus (wnv) infections in free-ranging birds were studied in slidell, st. tammany parish, louisiana, after a human encephalitis outbreak peaked there in july 2002. seroprevalence in resident, free-ranging wild birds in one suburban site was 25% and 24% in august and october, respectively, indicating that most transmission had ceased by early august. mortality rates, seroprevalence rates, host competence, and crude population estimates were used in mathematical models to predict actual ... | 2005 | 16354808 |
| phylogenetic analysis of avian poxviruses among free-ranging birds of virginia. | polymerase chain reaction was used to amplify a portion of the avian poxvirus core 4b gene of infected free-ranging birds that presented at the wildlife center of virginia during the 2003 and early 2004 years. the species of bird infected were a great blue heron (ardea herodias), two american crows (corvus brachyrhyncos), two american robins (turdus migratorius), two mourning doves (zenaida macroura), a red-tailed hawk (buteo jamaicensis), a blue-gray gnatcatcher (polioptila caerulea), a norther ... | 2005 | 16405007 |
| west nile virus antibodies in avian species of georgia, usa: 2000-2004. | west nile virus (wnv) was first isolated in the state of georgia in the summer of 2001. as amplifying hosts of wnv, avian species play an important role in the distribution and epidemiology of the virus. the objective of this study was to identify avian species that are locally involved as potential amplifying hosts of wnv and can serve as indicators of wnv transmission over the physiographic and land use variation present in the southeastern united states. avian serum samples (n=14,077) from 83 ... | 2006 | 16584328 |
| west nile virus surveillance in east baton rouge parish, louisiana. | west nile virus (wnv) was detected for the first time in louisiana in the fall of 2001. surveillance data collected from east baton rouge parish in 2002 were examined to establish baseline data on wnv activity, to support the current design of disease surveillance programs, and to target vector control efforts in the parish. the first indications of wnv activity were from a dead northern cardinal collected in february and from a live male cardinal sampled on 14 march. in mosquito pools, wnv was ... | 2007 | 17536365 |
| associations between two mosquito populations and west nile virus in harris county, texas, 2003-06. | associations between culex quinquefasciatus, aedes albopictus and west nile virus (wnv) activity, temperature, and rainfall in harris county, texas 2003-06 are discussed. human cases were highly correlated to cx. quinquefasciatus (r = 0.87) and ae. albopictus (r = 0.78) pools, blue jays (r = 0.83), and ae. albopictus collected (r = 0.71), but not cx. quinquefasciatus collected (r = 0.45). human cases were associated with temperature (r = 0.71), not rainfall (r = 0.29), whereas temperature correl ... | 2007 | 17939505 |
| host-feeding patterns of culex mosquitoes in relation to trap habitat. | mosquito feeding patterns identify vertebrate species potentially involved in the amplification of west nile virus. in new york, northern cardinals (cardinalis cardinalis) were the predominant hosts in most habitats. crow (corvus sp.) blood meals were most frequently identified from sewage treatment plant and storm water catch basin habitats. | 2007 | 18258048 |
| west nile virus antibodies in permanent resident and overwintering migrant birds in south-central kansas. | we conducted serological studies, using epitope-blocking elisas directed at west nile virus (wnv) and flavivirus antibodies, of wild birds in south-central kansas, the first for this state, in the winters of 2003-04 through 2005-06. overwintering migratory species (primarily the american tree sparrow and dark-eyed junco) consistently showed significantly lower seropositivity than permanent residents (primarily the northern cardinal). the cardinal showed annual variation in seropositivity between ... | 2008 | 18471059 |
| spatial variation in an avian host community: implications for disease dynamics. | because many pathogens can infect multiple host species within a community, disease dynamics in a focal host species can be affected by the composition of the host community. we examine the extent to which spatial variation in species' abundances in an avian host community may contribute to geographically varying prevalence of a recently emerged wildlife pathogen. mycoplasma gallisepticum is a pathogen novel to songbirds that has caused substantial mortality in house finches (carpodacus mexicanu ... | 2010 | 20130959 |
| field-based estimates of avian mortality from west nile virus infection. | one of the unique characteristics of west nile virus (wnv) in north america is the large number of bird species for which the virus can be fatal. wnv mortality has been documented through experimental infections of captive birds and necropsies of free-ranging birds. investigations of wnv-related mortality in wild birds often focus on species with dramatic population declines (e.g., american crow, corvus brachyrhynchos); however, few studies have addressed wnv-related mortality in species not exh ... | 2010 | 20370425 |
| host feeding patterns of culex mosquitoes (diptera: culicidae) in east baton rouge parish, louisiana. | host feeding patterns were examined for four species of culex mosquitoes collected from 18 sites in or adjacent to east baton rouge parish, la, from november 2002 to october 2004. host dna from 37 bloodfed culex coronator dyar and knab, 67 bloodfed cx. salinarius coquillett, 112 bloodfed cx. nigripalpus theobald, and 684 bloodfed cx. quinquefasciatus say were identified. the percentages of bloodmeals containing mammalian dna were 94.6% for cx. coronator, 82.1% for cx. salinarius, 66.1% for cx. n ... | 2010 | 20380306 |
| a multi-year study of mosquito feeding patterns on avian hosts in a southeastern focus of eastern equine encephalitis virus. | abstract. eastern equine encephalitis virus (eeev) is a mosquito-borne pathogen that cycles in birds but also causes severe disease in humans and horses. we examined patterns of avian host use by vectors of eeev in alabama from 2001 to 2009 using blood-meal analysis of field-collected mosquitoes and avian abundance surveys. the northern cardinal (cardinalis cardinalis) was the only preferred host (fed on significantly more than expected based on abundance) of culiseta melanura, the enzootic vect ... | 2011 | 21540380 |
| Dynamic selective environments and evolutionary traps in human-dominated landscapes. | Human activities can alter selective environments in ways that can reduce the usefulness of certain ornamental traits as honest signals of individual quality and, in some cases, may create evolutionary traps, where rapid changes in selective environments result in maladaptive behavioral decisions. Using the sexually dichromatic, socially monogamous Northern Cardinal (Cardinalis cardinalis) as a model, we hypothesized that urbanization would erode the relationship between plumage coloration and r ... | 2011 | 21939074 |
| the culex pipiens complex in the mississippi river basin: identification, distribution, and bloodmeal hosts. | members of the culex pipiens complex are the primary vectors of st. louis encephalitis virus and west nile virus in the mississippi river basin (mrb). the cx. pipiens complex in the mrb is composed of 4 taxa: cx. p. pipiens form pipiens, cx. p. quinquefasciatus, hybrids between cx. p. pipiens f. pipiens and cx. p. quinquefasciatus, and cx. p. pipiens form molestus. three studies on bloodmeal hosts with large sample sizes have been conducted on members of the cx. pipiens complex in the mrb includ ... | 2012 | 23401948 |
| vector-host interactions of culiseta melanura in a focus of eastern equine encephalitis virus activity in southeastern virginia. | eastern equine encephalitis virus (eeev) causes a highly pathogenic mosquito-borne zoonosis that is responsible for sporadic outbreaks of severe illness in humans and equines in the eastern usa. culiseta (cs.) melanura is the primary vector of eeev in most geographic regions but its feeding patterns on specific avian and mammalian hosts are largely unknown in the mid-atlantic region. the objectives of our study were to: 1) identify avian hosts of cs. melanura and evaluate their potential role in ... | 2015 | 26327226 |
| spatiotemporal exploratory models for broad-scale survey data. | the distributions of animal populations change and evolve through time. migratory species exploit different habitats at different times of the year. biotic and abiotic features that determine where a species lives vary due to natural and anthropogenic factors. this spatiotemporal variation needs to be accounted for in any modeling of species' distributions. in this paper we introduce a semiparametric model that provides a flexible framework for analyzing dynamic patterns of species occurrence an ... | 2010 | 21265447 |
| epidemiology of west nile virus: a silent epiornitic in northern delaware in 2007 without associated human cases. | abstract. we performed a 2-year longitudinal study (2006-2007) of west nile virus (wnv) infections in wild birds, mosquitoes, and sentinel chickens at 6 wnv-endemic sites in northern delaware. we determined virus infection rates of culex pipiens and other mosquito vectors as well as seroprevalence and antibody titers of amplifying hosts. endemicity status varied widely among the 6 sites based on 3 criteria-mosquito infections, sentinel chicken seropositivity, and wild bird seropositivity. a high ... | 2010 | 21033054 |
| associations of passerine birds, rabbits, and ticks with borrelia miyamotoi and borrelia andersonii in michigan, u.s.a. | wild birds contribute to maintenance and dissemination of vectors and microbes, including those that impact human, domestic animal, and wildlife health. here we elucidate roles of wild passerine birds, eastern cottontail rabbits (sylvilagus floridanus), and ixodes dentatus ticks in enzootic cycles of two spirochetes, borrelia miyamotoi and b. andersonii in a region of michigan where the zoonotic pathogen b. burgdorferi co-circulates. | 2012 | 23057837 |
| new species of parasitic quill mites of the genus picobia (acari: syringophilidae: picobiinae) from north american birds. | five new species of the genus picobia are described and illustrated: (1) p. leucophaeus sp. nov. from the laughing gull leucophaeus atricilla l. (charadriiformes: laridae) from texas; (2) p. troglodytes sp. nov. from the house wren troglodytes aedon vieillot (passeriformes: troglodytidae) from california; (3) p. cardinalis sp. nov. from the northern cardinal cardinalis cardinalis (l.) (passeriformes: cardinalidae) from texas; (4) p. carpodacus sp. nov. from the purple finch carpodacus purpureus ... | 2010 | 20939365 |
| new records of ixodes affinis (acari: ixodidae) parasitizing avian hosts in southeastern virginia. | ixodes affinis neumann (acari: ixodidae) is a hard-bodied tick species distributed throughout much of the southeastern united states. although i. affinis does not parasitize humans, it is a competent vector of borrelia burgdorferi sensu stricto, the causative-agent of lyme disease, and thus contributes to the enzootic maintenance of this pathogen. this study presents evidence of i. affinis parasitizing five new host passerine species. during 2012-2014, 1,888 birds were captured and examined for ... | 2016 | 26586535 |
| vector-host interactions and epizootiology of eastern equine encephalitis virus in massachusetts. | eastern equine encephalitis (eee) virus is a highly pathogenic mosquito-borne zoonosis that is responsible for outbreaks of severe disease in humans and equines, resulting in high mortality or severe neurological impairment in most survivors. in the northeastern united states, eee virus is maintained in an enzootic cycle involving the ornithophilic mosquito, culiseta melanura (coquillett) and passerine birds in freshwater swamp habitats. to evaluate the role of cs. melanura and culiseta morsitan ... | 2013 | 23473221 |
| host-seeking activity and avian host preferences of mosquitoes associated with west nile virus transmission in the northeastern u.s.a. | mosquito host-seeking activity was studied using a custom-designed trap to explore: (1) at which time interval of the night adult mosquito abatement would be most effective, and (2) if there exists an avian-specific host-seeking preference. overnight trials using traps baited with dry ice showed that aedes taeniorhynchus (wiedemann) was most active at dusk and was then captured throughout the night. in contrast, culex spp. (cx. pipiens (linnaeus) and cx. restuans (theobald) delayed most activity ... | 2010 | 20618650 |
| developing gis-based eastern equine encephalitis vector-host models in tuskegee, alabama. | a site near tuskegee, alabama was examined for vector-host activities of eastern equine encephalomyelitis virus (eeev). land cover maps of the study site were created in arcinfo 9.2 from quickbird data encompassing visible and near-infrared (nir) band information (0.45 to 0.72 microm) acquired july 15, 2008. georeferenced mosquito and bird sampling sites, and their associated land cover attributes from the study site, were overlaid onto the satellite data. sas 9.1.4 was used to explore univariat ... | 2010 | 20181267 |
| prevalence of west nile virus in migratory birds during spring and fall migration. | to investigate the role of migratory birds in the dissemination of west nile virus (wnv), we measured the prevalence of infectious wnv and specific wnv neutralizing antibodies in birds, principally passeriformes, during spring and fall migrations in the atlantic and mississippi flyways from 2001-2003. blood samples were obtained from 13,403 birds, representing 133 species. specific wnv neutralizing antibody was detected in 254 resident and migratory birds, representing 39 species, and was most c ... | 2009 | 19996451 |
| mites of the genus torotrogla (prostigmata: syringophilidae) from north american passerines. | five new quill mite species of the genus torotrogla kethley, 1970 (acari: syringophilidae) are described from north american passerines: t. aphelocoma sp.n. from aphelocoma californica (corvidae) and t. cardinalis sp.n. from cardinalis cardinalis (cardinalidae) in texas; and t. coccothraustes sp.n. from coccothraustes vespertinus (fringillidae), t. cyanocitta sp.n. from cyanocitta stelleri (corvidae), and t. piranga sp.n. from piranga ludoviciana (thraupidae) in california. a key to females of a ... | 2009 | 19351069 |
| avian host community structure and prevalence of west nile virus in chicago, illinois. | vertebrate host diversity has been postulated to mediate prevalence of zoonotic, vector-borne diseases, such that as diversity increases, transmission dampens. this "dilution effect" is thought to be caused by distribution of infective bites to incompetent reservoir hosts. we quantified avian species richness, avian seroprevalence for antibodies to west nile virus (wnv), and infection of wnv in culex mosquitoes, in the chicago metropolitan area, illinois, usa, a region of historically high wnv a ... | 2009 | 19034529 |
| urban land use predicts west nile virus exposure in songbirds. | urbanization is a widespread phenomenon that is likely to influence the prevalence and impact of wildlife pathogens, with implications for wildlife management and public health policies toward zoonotic pathogens. in this study, wild songbird populations were sampled at 14 sites along an urban rural gradient in the greater metropolitan atlanta (georgia, usa) area and tested for antibodies to west nile virus (wnv). the level of urbanization among sites was quantitatively assessed using a principal ... | 2008 | 18686573 |
| host choice and west nile virus infection rates in blood-fed mosquitoes, including members of the culex pipiens complex, from memphis and shelby county, tennessee, 2002-2003. | the source of bloodmeals in 2,082 blood-fed mosquitoes collected from february 2002 through december 2003 in memphis and surrounding areas of shelby county, tennessee were determined. members of the genus culex and anopheles quadrimaculatus predominated in the collections. members of the cx. pipiens complex and cx. restuans were found to feed predominately upon avian hosts, though mammalian hosts made up a substantial proportion of the bloodmeals in these species. no significant difference was s ... | 2007 | 17767413 |
| does the roosting behavior of birds affect transmission dynamics of west nile virus? | the potential role of many urban passerine birds in the transmission of west nile virus (wnv) is well-documented by studies on host competency, seroprevalence in wild birds, and identification of vector blood meal source. in contrast, the impact of bird behavior on transmission dynamics is largely unexplored. bird roosting (perching) behavior may be a critical component regulating wnv transmission because of the crepuscular/nocturnal feeding behavior of culex mosquitoes, the primary vectors of w ... | 2006 | 16896147 |
| host-feeding patterns of aedes albopictus (diptera: culicidae) in relation to availability of human and domestic animals in suburban landscapes of central north carolina. | aedes albopictus (skuse) (diptera: culicidae) is a major nuisance mosquito and a potential arbovirus vector. the host-feeding patterns of ae. albopictus were investigated during the 2002 and 2003 mosquito seasons in suburban neighborhoods in wake county, raleigh, nc. hosts of blood-fed ae. albopictus (n = 1,094) were identified with an indirect enzyme-linked immunosorbent assay, by using antisera made in new zealand white rabbits to the sera of animals that would commonly occur in peridomestic h ... | 2006 | 16739414 |
| songbird abundance and parasitism differ between urban and rural shrublands. | many studies have examined differences in avian community composition between urban and rural habitats, but few, if any, have looked at nesting success of urban shrubland birds in a replicated fashion while controlling for habitat. we tested factors affecting nest survival, parasitism by the brown-headed cowbird (molothrus ater), and species abundance in shrubland habitat in rural and urban landscapes. we found no support for our hypothesis that nest survival was lower in urban landscapes, but s ... | 2006 | 16705988 |
| relationship between bird abundances and landscape characteristics: the influence of scale. | scale is important to consider when investigating effects of the environment on a species. breeding bird survey (bbs) data and landscape metrics derived from aerial photographs were evaluated to determine how relationships of bird abundances with landscape variables changed over a continuous range of 16 spatial scales. we analyzed the average number of birds per stop (1985-1994) for five songbird species (family cardinalidae) for each of 50 stops on 198 bbs transects throughout six states in the ... | 2005 | 15952521 |
| vectest as diagnostic and surveillance tool for west nile virus in dead birds. | the vectest antigen-capture assay for west nile virus was performed on oral and tissue swabs from dead birds in new york state from april 2003 through july 2004. results were compared with those from real-time reverse transcriptase-polymerase chain reaction of kidney or brain. oral vectest sensitivity is adequate for surveillance in american crows (corvus brachyrhynchos) (87%), blue jays (cyanocitta cristata) (80%), and house sparrows (passer domesticus) (76%). oral vectest performed well for sm ... | 2004 | 15663856 |
| host feeding patterns of established and potential mosquito vectors of west nile virus in the eastern united states. | an important variable in determining the vectorial capacity of mosquito species for arthropod-borne infections is the degree of contact of the vector and the vertebrate reservoir. this parameter can be estimated by examining the host-feeding habits of vectors. serological and polymerase chain reaction based methods have been used to study the host-feedings patterns of 21 mosquito species from new york, new jersey, and tennessee, 19 of which previously have been found infected with west nile viru ... | 2004 | 15018775 |
| host-feeding habits of culex and other mosquitoes (diptera: culicidae) in the borough of queens in new york city, with characters and techniques for identification of culex mosquitoes. | the host-feeding patterns of mosquitoes (n = 247) collected in the borough of queens in new york city in july and august 2000 were investigated using an indirect elisa and a polymerase chain reaction (pcr)-heteroduplex assay. culex pipiens l. and cx. restuans theobald fed primarily on birds, and their feeding habits support their implication as enzootic vectors of west nile virus. culex salinarius coquillett and coquillettidia perturbans (walker) fed mainly on mammals, with fewer blood meals tak ... | 2002 | 12349862 |
| somatosensory feedback modulates the respiratory motor program of crystallized birdsong. | birdsong, like human speech, involves rapid, repetitive, or episodic motor patterns requiring precise coordination between respiratory, vocal organ, and vocal tract muscles. the song units or syllables of most adult songbirds exhibit a high degree of acoustic stereotypy that persists for days or months after the elimination of auditory feedback by deafening. adult song is assumed to depend on central motor programs operating independently from immediate sensory feedback. nothing is known, howeve ... | 2002 | 11943843 |
| direct observation of syringeal muscle function in songbirds and a parrot. | the role of syringeal muscles in controlling the aperture of the avian vocal organ, the syrinx, was evaluated directly for the first time by observing and filming through an endoscope while electrically stimulating different muscle groups of anaesthetised birds. in songbirds (brown thrashers, toxostoma rufum, and cardinals, cardinalis cardinalis), direct observations of the biomechanical effects of contraction largely confirm the functions of the intrinsic syringeal muscles proposed from indirec ... | 2002 | 11818409 |
| parvalbumin-positive projection neurons characterise the vocal premotor pathway in male, but not female, zebra finches. | parvalbumin (pv) and calbindin (cb) immunoreactivities were assessed in nucleus robustus archistriatalis (ra) of male and female zebra finches, together with retrograde labelling of ra neurons. the results of double and triple labelling experiments suggested that, in males, moderately and faintly pv-positive neurons were projection neurons, but that all intensely pv-positive cells were not. the latter, which are presumably interneurons, were also intensely cb-positive, and may correspond to the ... | 2001 | 11640910 |
| defensive responses of larval manduca sexta and their sensitization by noxious stimuli in the laboratory and field. | sensitization of defensive responses following noxious stimulation occurs in diverse species, but no demonstration of nociceptive sensitization in insects has been reported. a set of defensive behavior patterns in larval manduca sexta is described and shown to undergo sensitization following noxious mechanical stimulation. the striking response is a rapid bending that accurately propels the head towards sharply poking or pinching stimuli applied to most abdominal segments. the strike is accompan ... | 2001 | 11171298 |
| predicted and observed mortality from vector-borne disease in small songbirds. | numerous diseases of wildlife have recently emerged due to trade and travel. however, the impact of disease on wild animal populations has been notoriously difficult to detect and demonstrate, due to problems of attribution and the rapid disappearance of bodies after death. determining the magnitude of avian mortality from west nile virus (wnv) is emblematic of these challenges. although correlational analyses may show population declines coincident with the arrival of the virus, strong inferenc ... | 0 | 23956457 |
| limited spillover to humans from west nile virus viremic birds in atlanta, georgia. | west nile virus (wnv) is a mosquito-borne pathogen that impacts the health of its passerine bird hosts as well as incidentally infected humans in the united states. intensive enzootic activity among the hosts and vectors does not always lead to human outbreaks, as is the situation throughout much of the southeastern united states. in georgia, substantial yearly evidence of wnv in the mosquito vectors and avian hosts since 2001 has only led to 324 human cases. although virus has been consistently ... | 2013 | 24107200 |
| risk of exposure to eastern equine encephalomyelitis virus increases with the density of northern cardinals. | for a variety of infectious diseases, the richness of the community of potential host species has emerged as an important factor in pathogen transmission, whereby a higher richness of host species is associated with a lowered disease risk. the proposed mechanism driving this pattern is an increased likelihood in species-rich communities that infectious individuals will encounter dead-end hosts. mosquito-borne pathogen systems potentially are exceptions to such "dilution effects" because mosquito ... | 2013 | 23469095 |
| the effect of exogenous corticosterone on west nile virus infection in northern cardinals (cardinalis cardinalis). | the relationship between stress and disease is thought to be unambiguous: chronic stress induces immunosuppression, which likely increases the risk of infection. however, this link has not been firmly established in wild animals, particularly whether stress hormones affect host responses to zoonotic pathogens, which can be transmitted to domesticated animal, wildlife and human populations. due to the dynamic effects of stress hormones on immune functions, stress hormones may make hosts better or ... | 2012 | 22520572 |
| dynamics of vector-host interactions in avian communities in four eastern equine encephalitis virus foci in the northeastern u.s. | eastern equine encephalitis (eee) virus (togaviridae, alphavirus) is a highly pathogenic mosquito-borne zoonosis that is responsible for occasional outbreaks of severe disease in humans and equines, resulting in high mortality and neurological impairment in most survivors. in the past, human disease outbreaks in the northeastern u.s. have occurred intermittently with no apparent pattern; however, during the last decade we have witnessed recurring annual emergence where eee virus activity had bee ... | 2016 | 26751704 |
| spatial, temporal, molecular, and intraspecific differences of haemoparasite infection and relevant selected physiological parameters of wild birds in georgia, usa. | the prevalence of five avian haemoparasite groups was examined for effects on health and associations with extrinsic factors. overall, 786 samples were examined from six sites in two georgia (usa) watersheds, during breeding and non-breeding periods in 2010 and 2011. among the four most commonly infected species, haemoproteus prevalence was significantly higher in northern cardinals (cardinalis cardinalis) compared to indigo buntings (passerina cyanea) and tufted titmice (baeolophus bicolor) whi ... | 2013 | 24533333 |
| avian species diversity and transmission of west nile virus in atlanta, georgia. | the dilution effect is the reduction in vector-borne pathogen transmission associated with the presence of diverse potential host species, some of which are incompetent. it is popularized as the notion that increased biodiversity leads to decreased rates of disease. west nile virus (wnv) is an endemic mosquito-borne virus in the united states that is maintained in a zoonotic cycle involving various avian host species. in atlanta, georgia, substantial wnv presence in the vector and host species h ... | 2017 | 28159002 |
| supersuppression: reservoir competency and timing of mosquito host shifts combine to reduce spillover of west nile virus. | in the eastern united states, human cases of west nile virus (wnv) result from spillover from urban epizootic transmission between passerine birds and culex mosquitoes. in atlanta, ga, substantial wnv presence in hosts and vectors has not resulted in the human disease burden observed in cities with similar infection pressure. our study goal was to investigate extrinsic ecological conditions that potentially contribute to these reduced transmission rates. we conducted wnv surveillance among hosts ... | 2016 | 27503511 |
| the timing of visual object categorization. | an object can be categorized at different levels of abstraction: as natural or man-made, animal or plant, bird or dog, or as a northern cardinal or pyrrhuloxia. there has been growing interest in understanding how quickly categorizations at different levels are made and how the timing of those perceptual decisions changes with experience. we specifically contrast two perspectives on the timing of object categorization at different levels of abstraction. by one account, the relative timing implie ... | 2011 | 21811480 |
| west nile virus antibody decay rate in free-ranging birds. | antibody duration, following a humoral immune response to west nile virus (wnv) infection, is poorly understood in free-ranging avian hosts. quantifying antibody decay rate is important for interpreting serologic results and for understanding the potential for birds to serorevert and become susceptible again. we sampled free-ranging birds in chicago, illinois, us, from 2005 to 2011 and atlanta, georgia, us, from 2010 to 2012 to examine the dynamics of antibody decay following natural wnv infecti ... | 2015 | 25919465 |
| association between agricultural land use and west nile virus antibody prevalence in iowa birds. | in the plains states of the central united states, research suggests that the prevalence of west nile virus (wnv) disease in humans is higher in agricultural areas than in nonagricultural areas. in contrast, there is limited information about wnv exposure in birds, the primary amplifying host of wnv, in agriculturally dominated landscapes. we evaluated whether exposure to wnv in peridomestic birds sampled in central iowa varied with the proportion of land use devoted to agriculture. over the sum ... | 2013 | 24502714 |
| west nile virus infection rates and avian serology in east-central illinois. | understanding the geographic role of different species of mosquito vectors and vertebrate hosts in west nile virus (wnv) transmission cycles can facilitate the development and implementation of targeted surveillance and control measures. this study examined the relationship between wnv-antibody rates in birds and mosquito infection rates and bloodfeeding patterns in east-central illinois. the earliest detection of wnv-rna by reverse transcription-polymerase chain reaction taqman was from culex r ... | 2013 | 23923325 |
| 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 |
| a review of the mite subfamily harpirhynchinae (acariformes: harpirhynchidae)--parasites of new world birds (aves: neognathae). | mites of the subfamily harpirhynchinae (acariformes: cheyletoidea: harpirhynchidae) associated with neognathous birds (aves: neognathae) in the new world are revised. in all, 68 species in 8 genera are recorded. among them, 27 new species and 1 new genus are described as new for science: harpyrhynchoides gallowayi bochkov, oconnor and klompen sp. nov. from columba livia (columbiformes: columbidae) from canada (manitoba), h. zenaida bochkov, oconnor and klompen sp. nov. from zenaida macroura (col ... | 2015 | 26624161 |
| amblyomma auricularium (ixodida: ixodidae) in florida: new hosts and distribution records. | previous published evidence for the occurrence of an exotic armadillo tick, amblyomma auricularium (conil), in florida is scant, but we found it is fully established and integrated into the state's tick fauna. we collected 11,192 specimens of this tick from naturalized nine-banded armadillos, dasypus novemcinctus l., and 14 other species of wild native mammals and birds in florida, while sampling statewide during 2004 through 2007. in all, we document its specific presence only in 14 contiguous ... | 2017 | 28082640 |
| stifle disarticulation as a pelvic limb amputation technique in a cockatiel ( nymphicus hollandicus ) and a northern cardinal ( cardinalis cardinalis ). | this clinical report describes the use of stifle disarticulation in 2 avian patients as an alternative to transfemoral limb amputation. a northern cardinal ( cardinalis cardinalis ) was presented for soft tissue swelling and a traumatic fracture of the third digit of the left limb, with secondary bacterial infection and necrosis. a 25-year-old cockatiel ( nymphicus hollandicus ) was diagnosed with distal extremity necrosis after a nonunion of a closed tibiotarsal fracture. in both cases amputati ... | 2017 | 28358606 |
| distribution and prevalence of haemosporidian parasites in the northern cardinal (cardinalis cardinalis). | avian haemosporidian parasites provide a model system for understanding ecological and evolutionary host-parasite interactions. the diversity and distribution of these parasites remains incomplete, and, here, we provide the first range-wide assessment of avian haemosporidians in a continentally distributed host, the northern cardinal ( cardinalis cardinalis ). based on molecular techniques, we show geographical differences in prevalence and lineage diversity between host subspecies and identify ... | 2017 | 27700232 |
| sources of variation in plasma corticosterone and dehydroepiandrosterone in the male northern cardinal (cardinalis cardinalis): ii. effects of urbanization, food supplementation and social stress. | perturbations in an organism's environment can induce significant shifts in hormone secretory patterns. in this context, the glucocorticoid (gc) steroids secreted by the adrenal cortex have received much attention from ecologists and behaviorists due to their role in the vertebrate stress response. adrenal gcs, such as corticosterone (cort), are highly responsive to instability in environmental and social conditions. however, little is understood about how adrenal dehydroepiandrosterone (dhea) i ... | 2016 | 27255367 |
| sources of variation in plasma corticosterone and dehydroepiandrosterone in the male northern cardinal (cardinalis cardinalis): i. seasonal patterns and effects of stress and adrenocorticotropic hormone. | the secretion of steroids from the adrenal gland is a classic endocrine response to perturbations that can affect homeostasis. during an acute stress response, glucocorticoids (gc), such as corticosterone (cort), prepare the metabolic physiology and cognitive abilities of an animal in a manner that promotes survival during changing conditions. although gc functions during stress are well established, much less is understood concerning how adrenal androgens, namely dehydroepiandrosterone (dhea) a ... | 2016 | 27255363 |
| do seasonal patterns of rat snake (pantherophis obsoletus) and black racer (coluber constrictor) activity predict avian nest predation? | avian nest success often varies seasonally and because predation is the primary cause of nest failure, seasonal variation in predator activity has been hypothesized to explain seasonal variation in nest success. despite the fact that nest predator communities are often diverse, recent evidence from studies of snakes that are nest predators has lent some support to the link between snake activity and nest predation. however, the strength of the relationship has varied among studies. explaining th ... | 2016 | 27099708 |
| lingual articulation in songbirds. | lingual articulation in humans is one of the primary means of vocal tract resonance filtering that produces the characteristic vowel formants of speech. in songbirds, the function of the tongue in song has not been thoroughly examined, although recent research has identified the oropharyngeal-esophageal cavity as a resonance filter that is actively tuned to the frequency of the song. in northern cardinals (cardinalis cardinalis), the volume of this cavity is inversely proportional to the frequen ... | 2016 | 26685174 |
| toxic exposure of songbirds to lead in the southeast missouri lead mining district. | mining and smelting in the southeast missouri lead mining district has caused widespread contamination of soils with lead (pb) and other metals. soils from three study sites sampled in the district contained from approximately 1,000-3,200 mg pb/kg. analyses of earthworms [33-4,600 mg pb/kg dry weight (dw)] collected in the district showed likely high pb exposure of songbirds preying on soil organisms. mean tissue pb concentrations in songbirds collected from the contaminated sites were greater ( ... | 2013 | 23771631 |
| temperature can interact with landscape factors to affect songbird productivity. | increased temperatures and more extreme weather patterns associated with global climate change can interact with other factors that regulate animal populations, but many climate change studies do not incorporate other threats to wildlife in their analyses. we used 20 years of nest-monitoring data from study sites across a gradient of habitat fragmentation in missouri, usa, to investigate the relative influence of weather variables (temperature and precipitation) and landscape factors (forest cov ... | 2013 | 23504884 |
| model for vocalization by a bird with distensible vocal cavity and open beak. | some birds make use of a distensible oral cavity to produce nearly pure-tone song. songbirds such as the northern cardinal (cardinalis cardinalis) have a muscularly distended oropharyngeal-esophageal cavity between the top of the trachea and the open beak. the present paper analyzes the acoustics of this vocal system. it is shown that the resonance of the oropharyngeal-esophageal cavity, vented through the beak, introduces a dominant peak in the radiation efficiency, the frequency of which can b ... | 2006 | 16521762 |
| monitoring exposure of northern cardinals, cardinalis cardinalis, to cholinesterase-inhibiting pesticides: enzyme activity, reactivations, and indicators of environmental stress. | northern cardinals (cardinalis cardinalis) frequently use agricultural field edges in northeast arkansas, usa, and may be at risk of exposure to cholinesterase (che)-inhibiting pesticides. we monitored northern cardinal exposure to che-inhibiting pesticides by comparing plasma total che (tche) activity to reference-derived benchmarks and tche reactivations. total che and acetylcholinesterase (ache) were measured for 128 plasma samples from 104 northern cardinals from nine study sites. of birds s ... | 2005 | 16050589 |
| an unusual coccidian parasite causing pneumonia in a northern cardinal (cardinalis cardinalis). | in june 1993 an unusual coccidian parasite was identified in lung tissue from a northern cardinal (cardinalis cardinalis), collected near tucson, arizona (usa), which died in respiratory distress. histologically, there was evidence of severe, generalized interstitial pneumonia, associated with the parasite. both asexual and sexual stages were seen. schizonts, gamonts, and sporulated oocysts were seen in lung tissue. the parasite most closely resembled coccidia of the genus lankesterella. this is ... | 1996 | 8627925 |
| five new species of isospora from hawaiian birds. | the following species are described from hawaiian birds: isospora brayi sp. n., with oocysts 27 x 26 micron and sporocysts 19 x 12 micron, from the japanese white-eye, zosterops japonicus temminck & schlegel; isospora cardinalis sp. n., with oocysts 24 x 23 micron, and sporocysts 16 x 10 micron, from the cardinal, cardinalis cardinalis (linnaeus); isospora ivensae sp. n., with oocysts 26 x 25 micron, and sporocysts 18 x 12 micron, from the spotted or white-throated munia, lonchura punctulata (li ... | 1980 | 7452523 |
| when the birds go unheard: highway noise disrupts information transfer between bird species. | highway infrastructure and accompanying vehicle noise is associated with decreased wildlife populations in adjacent habitats. noise masking of animal communication is an oft-cited potential mechanism underlying species loss in sound-polluted habitats. this study documents the disruption of between-species information transfer by anthropogenic noise. titmice and chickadees broadcast specific calls to alert kin of predator threats, and sympatric vertebrates eavesdrop on these alarm calls to avoid ... | 2016 | 27095267 |
| heavy metal bioaccumulation in two passerines with differing migration strategies. | various anthropogenic activities have resulted in concentration of heavy metals and contamination of surrounding environments. historically, heavy metal contamination at the savannah river site (srs) in south carolina has resulted from accidental releases of stored waste generated from nuclear weapon production in the early 1950s. songbirds inhabiting and using resources from these areas have the potential to bioaccumulate metals but there is limited information on metal concentration levels in ... | 2017 | 28292671 |
| homeostatic regulation in physiological systems: a versatile ansatz. | a generic modelling formalism is described for homeostatic dynamics in physiological systems. the method is particularly suited where the peripheral, physiological system itself is well-characterised, but the details of the central, regulatory component (the nervous and endocrine systems) have not necessarily been characterised in full detail. the method is applied to temperature regulation in cardinalis cardinalis, c. sinuatus, lepus alleni, and passer domesticus, and furthermore to hydrominera ... | 2015 | 26282014 |
| declining brown-headed cowbird (molothrus ater) populations are associated with landscape-specific reductions in brood parasitism and increases in songbird productivity. | many songbird species have experienced significant population declines, partly because of brood parasitism by the brown-headed cowbird (molothrus ater), which is positively associated with increasing landscape forest cover in the midwestern united states. however, cowbirds are also experiencing long-term population declines, which should reduce parasitism pressure and thus increase productivity of host species. we used 20 years of nest monitoring data from five sites in missouri across a gradien ... | 2012 | 23077647 |
| acclimatization of seasonal energetics in northern cardinals (cardinalis cardinalis) through plasticity of metabolic rates and ceilings. | northern cardinals (cardinalis cardinalis) are faced with energetically expensive seasonal challenges that must be met to ensure survival, including thermoregulation in winter and reproductive activities in summer. contrary to predictions of life history theory that suggest breeding metabolic rate should be the apex of energetic effort, winter metabolism exceeds that during breeding in several temperate resident bird species. by examining whole-animal, tissue and cellular function, we ask whethe ... | 2012 | 22723481 |
| testosterone elevation and response to gonadotropin-releasing hormone challenge by male northern cardinals (cardinalis cardinalis) following aggressive behavior. | there is much discrepancy about the relationship between testosterone (t) and male aggressive behavior. for example, in birds, males of many species significantly elevate t levels during inter-male conflict. however, this is not universal, and in species where males typically do not elevate t during aggressive interactions, concentrations of the hormone are often assumed to be circulating at maximum levels. we examined if male northern cardinals (cardinalis cardinalis) significantly elevated t d ... | 2012 | 22613708 |
| non-breeding gonadal testosterone production of male and female northern cardinals (cardinalis cardinalis) following gnrh challenge. | yearly, testosterone (t) levels fluctuate as many vertebrates cycle through reproductive and non-reproductive periods. among many temperate birds, it is well established that levels of t peak as gonads recrudesce for breeding and then fall as gonads regress prior to the non-breeding season. while the tissues producing breeding season t are well studied, the tissues responsible for non-breeding t have received less investigative attention. we examined the ability of male and female northern cardi ... | 2011 | 21986087 |
| the effect of sex on avian plasma cholinesterase enzyme activity: a potential source of variation in an avian biomarker endpoint. | accurate identification of contaminant exposure to nontarget organisms involves understanding sources of variation associated with contaminant specific biomarkers. cholinesterase (che) enzyme activity is the biochemical endpoint most often used to assess organism exposure to organophosphorus (op) pesticides. a potential source of variation for this biomarker is sex, however, a generalized pattern of sex as a source of variation for avian che levels remains equivocal. in this study, sex-dependent ... | 2004 | 15386151 |
| the influence of carotenoid acquisition and utilization on the maintenance of species-typical plumage pigmentation in male american goldfinches (carduelis tristis) and northern cardinals (cardinalis cardinalis). | birds display a tremendous variety of carotenoid-based colors in their plumage, but the mechanisms underlying interspecific variability in carotenoid pigmentation remain poorly understood. because vertebrates cannot synthesize carotenoids de novo, access to pigments in the diet is one proximate factor that may shape species differences in carotenoid-based plumage coloration. however, some birds metabolize ingested carotenoids and deposit pigments that differ in color from their dietary precursor ... | 2006 | 11731975 |
| repetitions and pattern switches in songs of cardinals, cardinalis cardinalis. | a correlation is established between repetitions of leading syllables in the songs of cardinals and those which follow. the time intervals following repeated syllables relate first to acceleration at the beginning of a song but as the song progresses they relate more directly to the duration of the syllables. on the other hand the switch-intervals between different kinds of syllablles relate more to the duration of the following syllable, although acceleration at the beginning of the song may ob ... | 1975 | 1210812 |
| avian thermoregulation in the heat: resting metabolism, evaporative cooling, and heat tolerance in sonoran desert songbirds. | we examined thermoregulatory performance in seven sonoran desert passerine bird species varying in body mass from 10 to 70g - lesser goldfinch, house finch, pyrrhuloxia, cactus wren, northern cardinal, abert's towhee and curve-billed thrasher. using flow-through respirometry we measured daytime resting metabolism, evaporative water loss and body temperature at air temperatures (tair) between 30° and 52°c. we found marked increases in resting metabolism above the upper critical temperature (tuc), ... | 2017 | 28684465 |
| examining the role of effective population size on mitochondrial and multilocus divergence time discordance in a songbird. | estimates of speciation times are subject to a number of potential errors. one source of bias is that effective population size (ne) has been shown to influence substitution rates. this issue is of particular interest for phylogeographic studies because population sizes can vary dramatically among genetically structured populations across species' ranges. in this study, we used multilocus data to examine temporal phylogeographic patterns in a widespread north american songbird, the northern card ... | 2013 | 23457463 |
| epidemiology of a salmonella enterica subsp. enterica serovar typhimurium strain associated with a songbird outbreak. | salmonella enterica subsp. enterica serovar typhimurium is responsible for the majority of salmonellosis cases worldwide. this salmonella serovar is also responsible for die-offs in songbird populations. in 2009, there was an s. typhimurium epizootic reported in pine siskins in the eastern united states. at the time, there was also a human outbreak with this serovar that was associated with contaminated peanuts. as peanuts are also used in wild-bird food, it was hypothesized that the pine siskin ... | 2012 | 22885752 |
| the role of historical and contemporary processes on phylogeographic structure and genetic diversity in the northern cardinal, cardinalis cardinalis. | earth history events such as climate change are believed to have played a major role in shaping patterns of genetic structure and diversity in species. however, there is a lag between the time of historical events and the collection of present-day samples that are used to infer contemporary population structure. during this lag phase contemporary processes such as dispersal or non-random mating can erase or reinforce population differences generated by historical events. in this study we evaluat ... | 2011 | 21599972 |
| vocal tract motor patterns and resonance during constant frequency song: the white-throated sparrow. | bird song is a complex behavior that requires the coordination of several motor systems. sound is produced in the syrinx and then modified by the upper vocal tract. movements of the hyoid skeleton have been shown in the northern cardinal (cardinalis cardinalis) to be extensively involved in forming an oropharyngeal-esophageal cavity (oec), which contributes a major resonance to the vocal tract transfer function. here we report that a similar relationship exists between the volume of the oec and ... | 2009 | 19082607 |
| seasonal and sex-related variation in song control nuclei in a species with near-monomorphic song, the northern cardinal. | studies concerning the song control system (scs) in songbirds generally focus on males due to their prodigious song production. both seasonal and age related differences have been found in the size of male scs regions. among those studies that have addressed females some level of sexual size dimorphism has been found, with females generally having smaller scs area than males. among those species where female song has been studied, typically females either sing much less than males, or they duet ... | 2008 | 18692546 |
| mourning dove (zenaida macroura) wing-whistles may contain threat-related information for con- and hetero-specifics. | distinct acoustic whistles are associated with the wing-beats of many doves, and are especially noticeable when doves ascend from the ground when startled. i thus hypothesized that these sounds may be used by flock-mates as cues of potential danger. to test this hypothesis, i compared the responses of mourning doves (zenaida macroura), northern cardinals (cardinalis cardinalis), and house sparrows (passer domesticus) to audio playbacks of dove 'startle wing-whistles', cardinal alarm calls, dove ... | 2008 | 18551267 |
| consumer resource matching in urbanizing landscapes: are synanthropic species over-matching? | population responses of synanthropic species to urbanization may be explained by the resource-matching rule, which postulates that individuals should distribute themselves according to resource availability. according to the resource-matching rule, urban habitats will contain greater densities if they provide better resources than rural habitats. however, because resource availability is density dependent, individuals in urban areas would ultimately achieve fitness levels comparable to, but no b ... | 2008 | 18409440 |
| bloodmeal, host selection, and genetic admixture analyses of culex pipiens complex (diptera: culicidae) mosquitoes in chicago, il. | the area in and around chicago, il, is a hotspot of west nile virus activity. the discovery of a culex pipiens form molestus forskӓl population in chicago in 2009 added to speculation that offspring from hybridization between cx. pipiens f. pipiens l. and f. molestus could show a preference for feeding on humans. we collected blood-fed female mosquitoes (n = 1,023) from eight residential sites and one public park site in chicago in july and august 2012. bloodmeal analysis using the coi (cytochro ... | 2020 | 31576405 |
| predicting west nile virus transmission in north american bird communities using phylogenetic mixed effects models and ebird citizen science data. | west nile virus (wnv) is a mosquito-transmitted disease of birds that has caused bird population declines and can spill over into human populations. previous research has identified bird species that infect a large fraction of the total pool of infected mosquitoes and correlate with human infection risk; however, these analyses cover small spatial regions and cannot be used to predict transmission in bird communities in which these species are rare or absent. here we present a mechanistic model ... | 2019 | 31395085 |
| plumage brightness as an indicator of parental care in northern cardinals | good parent and differential allocation models predict relationships between degree of sexual ornamentation and parental care, but relatively few studies have tested these models. the northern cardinal, cardinalis cardinalis, is a sexually dichromatic species in which both sexes are ornamented. males have red plumage, and females have tan plumage with limited areas of red feathering. cardinals were used to address the two models and determine whether plumage brightness signals level of parental ... | 1998 | 9480678 |
| feeding success and host selection by culex quinquefasciatus say mosquitoes in experimental trials. | arthropod vector feeding preferences are defined as an overutilization of a particular host species given its abundance in relationship to other species in the community. numerous methods exist to quantify vector feeding preferences; however, controlled host choice experiments are generally an underutilized approach. in this report, we present results from controlled vector host choice experiments using culex quinquefasciatus say (diptera: culicidae) mosquitoes and wild avian hosts identified as ... | 2019 | 30964426 |
| forage ratio analysis of the southern house mosquito in college station, texas. | culex quinquefasciatus is the principal vector of west nile virus (wnv) in the south central united states, yet limited data on host utilization are available. we evaluated host utilization over a 3-month period in 2013 in a residential landscape in college station, texas. pcr sequencing of the mitochondrial cytochrome oxidase 1 gene permitted molecular identification of vertebrate bloodmeals to the species level. forage ratio analysis identified bird species that were overutilized and underutil ... | 2018 | 29920164 |
| per- and polyfluoroalkyl substances in two different populations of northern cardinals. | the northern cardinal (cardinalis cardinalis) is a good indicator species for environmental contaminants because it does not migrate and its range covers a diversity of habitats, including metropolitan atlanta, ga and the geographically isolated hawaiian islands. in addition, the cardinal is often found near people's homes, making it likely to be exposed to the same outdoor elements, including soil, groundwater, and air, that surrounding humans experience. in this study, blood serum concentratio ... | 2019 | 30710759 |
| influence of invasion history on rapid morphological divergence across island populations of an exotic bird. | there is increasing evidence that exotic populations may rapidly differentiate from those in their native range and that differences also arise among populations within the exotic range. using morphological and dna-based analyses, we document the extent of trait divergence among native north american and exotic hawaiian populations of northern cardinal (cardinalis cardinalis). furthermore, using a combination of historical records and dna-based analyses, we evaluate the role of founder effects i ... | 2018 | 29938053 |
| bill size variation in northern cardinals associated with anthropogenic drivers across north america. | allen's rule predicts that homeotherms inhabiting cooler climates will have smaller appendages, while those inhabiting warmer climates will have larger appendages relative to body size. birds' bills tend to be larger at lower latitudes, but few studies have tested whether modern climate change and urbanization affect bill size. our study explored whether bill size in a wide-ranging bird would be larger in warmer, drier regions and increase with rising temperatures. furthermore, we predicted that ... | 2018 | 29876062 |
| organochlorine chemical residues in northern cardinal (cardinalis cardinalis) eggs from greater washington, dc usa. | northern cardinal eggs from six neighborhoods near washington dc were analyzed for organochlorine pesticides and pcbs. all compounds were detected more frequently and at higher concentrations in more heavily urbanized neighborhoods. ddt (mostly as p,p'-dde) was detected in all neighborhoods. p,p'-ddt was typically 0.5‒16 ng/g (ww) in most suburban neighborhoods but was not detected (< 0.1 ng/g) in more rural areas; however, p,p'-ddt was 127‒1130 ng/g in eggs from two suburban maryland nests and ... | 2018 | 29796875 |
| corticosterone profiles in northern cardinals (cardinalis cardinalis): do levels vary through life history stages? | as animals move through life history stages, energy requirements for each stage will vary. both daily and annual variation in the glucocoriticoid hormones (specifically corticosterone, or cort, in birds) helps provide the variable energy needed through life history stages. in many bird species, cort is higher in the breeding season when energy demands can be quite high and is often lower in the non-breeding season. additionally, cort has a role to play in the response to stressful stimuli and th ... | 2018 | 29678726 |
| seasonal variation and correlation between corticosterone and the antioxidant uric acid during stress in the northern cardinal (cardinalis cardinalis). | glucocorticoids modify metabolism and other physiological processes in order to mount an appropriate response to stress. this stress response is affected by a combination of seasonal changes, life-history events, and environmental factors. determining seasonal variability and the potential connection between stress hormones and metabolism is fundamental in understanding seasonal physiological changes in animals. here, we compared an indicator of stress (corticosterone) with an indicator of metab ... | 2017 | 29356457 |
| field analysis of biological factors associated with sites at high and low to moderate risk for eastern equine encephalitis virus winter activity in florida. | eastern equine encephalitis virus (eeev) is the most pathogenic arbovirus endemic to the united states. studies have demonstrated florida's role as a regional reservoir for the virus and its ability to support year-round transmission. previous research has developed risk index models for mapping locations most at risk for eeev transmission. we compared vector abundance, vector feeding behavior, potential host species, and fauna presence at high versus low-moderate risk sites during the winter an ... | 2021 | 33893734 |