| social complexity can drive vocal complexity: group size influences vocal information in carolina chickadees. | one hypothesis to explain variation in vocal communication in animal species is that the complexity of the social group influences the group's vocal complexity. this social-complexity hypothesis for communication is also central to recent arguments regarding the origins of human language, but experimental tests of the hypothesis are lacking. this study investigated whether group size, a fundamental component of social complexity, influences the complexity of a call functioning in the social orga ... | 2006 | 16866738 |
| 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 |
| further investigations of the mite genus syringophiloidus kethley, 1970 (acariformes: syringophilidae) from north american passerines. | four new syringophilid species of syringophiloidus kethley, 1970 are described from north american passerines: s. zonotrichia n. sp. from zonotrichia albicolis (gmelin) (emberizidae) on texas; s. jackowiaki n. sp. from poecile carolinensis (auduborn) (paridae) in texas; and s. xanthocephalus n. sp. from xanthocephalus xanthocephalus (bonaparte) (icteridae) and s. agelaius n. sp. from agelaius phoeniceus linnaeus (icteridae), both from arizona. spizella breweri (cassin) (emberizidae) from califor ... | 2011 | 21643897 |
| external heart deformities in passerine birds exposed to environmental mixtures of polychlorinated biphenyls during development. | necropsy-observable cardiac deformities were evaluated from 283 nestling passerines collected from one reference site and five polychlorinated biphenyl (pcb)-contaminated sites around bloomington and bedford, indiana, usa. hearts were weighed and assessed on relative scales in three dimensions (height, length, and width) and for externally visible deformities. heart weights normalized to body weight (heart somatic index) were decreased significantly at the more contaminated sites in both house w ... | 2006 | 16519318 |
| site specific pcb-correlated interspecies differences in organ somatic indices. | we correlated site specific differences in the organ somatic indices of nestlings of five passerine species (tree swallow, red-winged blackbird, house wren, carolina chickadee, and eastern bluebird) with the degree of polychlorinated biphenyls (pcb) exposure in ovo and post-hatching. the birds were exposed to pcbs at or downstream of four pcb-contaminated sites. of the organs evaluated for this paper, brain, bursa, heart, kidneys, lungs, pancreas, spleen, stomach, and thyroid varied significantl ... | 2006 | 16317482 |
| diversity in mixed species groups improves success in a novel feeder test in a wild songbird community. | mixed-species groups are common and are thought to provide benefits to group members via enhanced food finding and antipredator abilities. these benefits could accrue due to larger group sizes in general but also to the diverse species composition in the groups. we tested these possibilities using a novel feeder test in a wild songbird community containing three species that varied in their dominant-subordinate status and in their nuclear-satellite roles: carolina chickadees (poecile carolinensi ... | 2017 | 28230159 |
| do carolina chickadees (poecile carolinensis) and tufted titmice (baeolophus bicolor) attend to the head or body orientation of a perched avian predator? | individuals of many prey species adjust their foraging behavior in response to the presence of a predator. responding to predators takes time away from searching for and exploiting food resources. to balance between the need to avoid predation and the need to forage, individuals should attend to cues from predators that indicate risk. two such cues might be the predator's head orientation (where it might be looking) and body orientation (where it might be moving). in the current study, flocks of ... | 2016 | 27195595 |
| the effects of extended exposure to traffic noise on parid social and risk-taking behavior. | traffic noise is a prevalent and yet poorly understood anthropogenic disturbance associated with reduced avian diversity, population densities and pairing and mating success. how these systems are affected is not clear as a direct experimental link between noise and behavior underlying these patterns is missing. here we provide the first empirical evidence of the effects of long-term exposure to simulated traffic noise on social and risk-taking behavior of carolina chickadees (poecile carolinens ... | 2012 | 22688079 |
| seasonal variation in avian auditory evoked responses to tones: a comparative analysis of carolina chickadees, tufted titmice, and white-breasted nuthatches. | we tested for seasonal plasticity of the peripheral auditory system of three north american members of the sylvioidea: carolina chickadees (poecile carolinensis), tufted titmice (baeolophus bicolor), and white-breasted nuthatches (sitta carolinensis). we measured three classes of auditory evoked responses (aer) to tone stimuli: sustained receptor/neural responses to pure-tone condensation waveforms, the frequency-following response (ffr), and the earliest peak of the aer to stimulus onset (tone ... | 2007 | 17066303 |
| benefits to satellite members in mixed-species foraging groups: an experimental analysis. | hypotheses proposed to explain the formation of mixed-species foraging groups have focused on both foraging and antipredation benefits. mixed-species flocks of bark-foraging birds form during the winter in the eastern deciduous forests of north america. these flocks are composed of two parid nuclear species, tufted titmice, baeolophus bicolor, and either carolina or black-capped chickadees, poecile carolinensis or p. atricapillus, and several satellite species including downy woodpeckers, picoid ... | 1998 | 9787042 |
| hg-contaminated terrestrial spiders pose a potential risk to songbirds at caddo lake (texas/louisiana, usa). | methylmercury (mehg) is an environmental contaminant that can have adverse effects on wildlife. because mehg is produced by bacteria in aquatic ecosystems, studies of mehg contamination of food webs historically have focused on aquatic organisms. however, recent studies have shown that terrestrial organisms such as songbirds can be contaminated with mehg by feeding on mehg-contaminated spiders. in the present study, the authors examined the risk that mehg-contaminated terrestrial long-jawed orb ... | 2015 | 25378235 |
| animal vocal sequences: not the markov chains we thought they were. | many animals produce vocal sequences that appear complex. most researchers assume that these sequences are well characterized as markov chains (i.e. that the probability of a particular vocal element can be calculated from the history of only a finite number of preceding elements). however, this assumption has never been explicitly tested. furthermore, it is unclear how language could evolve in a single step from a markovian origin, as is frequently assumed, as no intermediate forms have been fo ... | 2014 | 25143037 |
| estimating vocal repertoire size is like collecting coupons: a theoretical framework with heterogeneity in signal abundance. | vocal repertoire size is an important behavioural measure in songbirds and mammals with complex vocal communication systems, and has traditionally been used as an indicator of individual fitness, cognitive ability, and social structure. estimates of asymptotic repertoire size have typically been made using curve fitting techniques. however, the exponential model usually applied in these techniques has never been provided with a theoretical justification based on probability theory, and the model ... | 2015 | 25791282 |
| songbirds tradeoff auditory frequency resolution and temporal resolution. | physical tradeoffs may in some cases constrain the evolution of sensory systems. the peripheral auditory system, for example, performs a spectral decomposition of sound that should result in a tradeoff between frequency resolution and temporal resolution. we assessed temporal resolution in three songbird species using auditory brainstem responses to paired click stimuli. temporal resolution was greater in house sparrows (passer domesticus) than carolina chickadees (poecile carolinensis) and whit ... | 2011 | 21225270 |
| a comparative study of avian auditory brainstem responses: correlations with phylogeny and vocal complexity, and seasonal effects. | we conducted a comparative study of the peripheral auditory system in six avian species (downy woodpeckers, carolina chickadees, tufted titmice, white-breasted nuthatches, house sparrows, and european starlings). these species differ in the complexity and frequency characteristics of their vocal repertoires. physiological measures of hearing were collected on anesthetized birds using the auditory brainstem response to broadband click stimuli. if auditory brainstem response patterns are phylogene ... | 2002 | 12471495 |
| an investigation of sex differences in acoustic features in black-capped chickadee (poecile atricapillus) chick-a-dee calls. | sex differences have been identified in a number of black-capped chickadee vocalizations and in the chick-a-dee calls of other chickadee species [i.e., carolina chickadees (poecile carolinensis)]. in the current study, 12 acoustic features in black-capped chickadee chick-a-dee calls were investigated, including both frequency and duration measurements. using permuted discriminant function analyses, these features were examined to determine if any features could be used to identify the sex of the ... | 2016 | 27914410 |
| differential effects of climate and species interactions on range limits at a hybrid zone: potential direct and indirect impacts of climate change. | the relative contributions of climate versus interspecific interactions in shaping species distributions have important implications for closely related species at contact zones. when hybridization occurs within a contact zone, these factors regulate hybrid zone location and movement. while a hybrid zone's position may depend on both climate and interactions between the hybridizing species, little is known about how these factors interact to affect hybrid zone dynamics. here, we utilize sdm (spe ... | 2015 | 26640687 |
| spatiotemporally consistent genomic signatures of reproductive isolation in a moving hybrid zone. | studies of hybrid zone dynamics often investigate a single sampling period and draw conclusions from that temporal snapshot. stochasticity can, however, result in loci with spurious outlier patterns, which is exacerbated by limited temporal or geographic sampling. comparing admixed populations from different geographic regions is one way to detect repeatedly divergent genomic regions potentially involved in reproductive isolation. temporal comparisons also allow us to control partially for the r ... | 2014 | 25138643 |
| climate-mediated movement of an avian hybrid zone. | the interaction between sibling species that share a zone of contact is a multifaceted relationship affected by climate change [1, 2]. between sibling species, interactions may occur at whole-organism (direct or indirect competition) or genomic (hybridization and introgression) levels [3-5]. tracking hybrid zone movements can provide insights about influences of environmental change on species interactions [1]. here, we explore the extent and mechanism of movement of the contact zone between bla ... | 2014 | 24613306 |
| information theoretical approaches to chick-a-dee calls of carolina chickadees (poecile carolinensis). | one aim of this study was to apply information theoretical analyses to understanding the structural complexity of chick-a-dee calls of carolina chickadees, poecile carolinensis. a second aim of this study was to compare this structural complexity to that of the calls of black-capped chickadees, p. atricapillus, described in an earlier published report (hailman, ficken, & ficken, 1985). chick-a-dee calls were recorded from carolina chickadees in a naturalistic observation study in eastern tenness ... | 2012 | 21875178 |
| the relationship of metabolic performance and distribution in black-capped and carolina chickadees. | in endotherms, metabolic performance is associated with a wide array of ecological traits, including species distribution. researchers have suggested that the northern boundaries of north american passerines are limited by their ability to sustain the high metabolic rates required for thermoregulation. black-capped chickadees (poecile atricapillus; bc) are year-round residents in most of canada and the northern half of the united states, whereas carolina chickadees (poecile carolinensis; ca) are ... | 2010 | 20151817 |
| the influence of sampling design on species tree inference: a new relationship for the new world chickadees (aves: poecile). | in this study, we explore the long-standing issue of how many loci are needed to infer accurate phylogenetic relationships, and whether loci with particular attributes (e.g., parsimony informativeness, variability, gene tree resolution) outperform others. to do so, we use an empirical data set consisting of the seven species of chickadees (aves: paridae), an analytically tractable, recently diverged group, and well-studied ecologically but lacking a nuclear phylogeny. we estimate relationships u ... | 2014 | 24111665 |
| interspecific differences in the visual system and scanning behavior of three forest passerines that form heterospecific flocks. | little is known as to how visual systems and visual behaviors vary within guilds in which species share the same micro-habitat types but use different foraging tactics. we studied different dimensions of the visual system and scanning behavior of carolina chickadees, tufted titmice, and white-breasted nuthatches, which are tree foragers that form heterospecific flocks during the winter. all species had centro-temporally located foveae that project into the frontal part of the lateral visual fiel ... | 2013 | 23400841 |
| linking social complexity and vocal complexity: a parid perspective. | the paridae family (chickadees, tits and titmice) is an interesting avian group in that species vary in important aspects of their social structure and many species have large and complex vocal repertoires. for this reason, parids represent an important set of species for testing the social complexity hypothesis for vocal communication--the notion that as groups increase in social complexity, there is a need for increased vocal complexity. here, we describe the hypothesis and some of the early e ... | 2012 | 22641826 |
| group size and social interactions are associated with calling behavior in carolina chickadees (poecile carolinensis). | the complexity of a social group may influence the vocal behavior of group members. recent evidence in carolina chickadees, poecile carolinensis, indicated that one component of social complexity, group size, influenced the complexity of the "chick-a-dee" call, a vocalization functioning in social cohesion. individuals in larger social groups used calls with greater information than did individuals in smaller social groups. here, the authors review this earlier work, and describe a recent study ... | 2008 | 18729660 |
| behavioral consistency in a changed social context in carolina chickadees. | stable personality-like influences on behavior have been documented in nonhuman animals (s. d. gosling, 2001), but little is known about such influences within explicitly social contexts. the authors tested whether individuals of a socially complex avian species, carolina chickadees (poecile carolinensis), show consistent behavioral profiles when their social context changes. consistency was tested using 7 groups of chickadees, each group comprising 2 female-male pairs. the 2 pairs from each gro ... | 2007 | 17503697 |
| fecal corticosterone, body mass, and caching rates of carolina chickadees (poecile carolinensis) from disturbed and undisturbed sites. | we tested for hormonal and behavioral differences between carolina chickadees (poecile carolinensis) taken from a disturbed (recently logged) forest, an undisturbed forest, or a residential site. we measured fecal corticosterone and body mass levels in the field, and fecal corticosterone, body mass, and caching behavior in an aviary experiment. in the field, birds from the disturbed forest exhibited significantly higher fecal corticosterone levels than birds from either the undisturbed forest or ... | 2006 | 16458312 |
| variation in chick-a-dee calls of a carolina chickadee population, poecile carolinensis: identity and redundancy within note types. | chick-a-dee calls of chickadee species are structurally complex because calls possess a rudimentary syntax governing the ordering of their different note types. chick-a-dee calls were recorded in an aviary from female and male birds from two field sites. this paper reports sources of variation of acoustical parameters of notes in these calls. there were significant sex and microgeographic differences in some of the measured parameters of the notes in the calls. in addition, the syntax of the cal ... | 2003 | 12703723 |
| the effect of social dominance on fattening and food-caching behaviour in carolina chickadees, poecile carolinensis. | subordinates often have to wait for dominants to obtain food. as a result, their foraging success should be less predictable and they should therefore maintain a higher level of energy reserves compared with dominants. a corollary of this prediction is that subordinates should gain mass earlier in the day and maintain higher mass than dominants. we tested these predictions with captive carolina chickadees. in two different experiments (one where birds were given ad libitum access to food and the ... | 2000 | 11032651 |
| great tits encode contextual information in their food and mobbing calls. | the calling behaviour of paridae species (i.e. titmice, tits and chickadees) in a predator-related context is well-studied. parid species are known to alter call types, note composition or call duration according to predation risk. however, how these species encode information about a non-threatening context, such as food sources, has been subject to only few studies. studies in carolina chickadees (poecile carolinensis) have shown that this species alters the ratio of c and d notes to encode in ... | 2019 | 31827857 |
| genomic regions underlying metabolic and neuronal signaling pathways are temporally consistent in a moving avian hybrid zone. | the study of hybrid zones can provide insight into the genetic basis of species differences that are relevant for the maintenance of reproductive isolation. hybrid zones can also provide insight into climate change, species distributions, and evolution. the hybrid zone between black-capped chickadees (poecile atricapillus) and carolina chickadees (poecile carolinensis) is shifting northward in response to increasing winter temperatures but is not increasing in width. this pattern indicates stron ... | 2020 | 32243568 |
| conspecific olfactory preferences and interspecific divergence in odor cues in a chickadee hybrid zone. | understanding how mating cues promote reproductive isolation upon secondary contact is important in describing the speciation process in animals. divergent chemical cues have been shown to act in reproductive isolation across many animal taxa. however, such cues have been overlooked in avian speciation, particularly in passerines, in favor of more traditional signals such as song and plumage. here, we aim to test the potential for odor to act as a mate choice cue, and therefore contribute to pre ... | 2019 | 31534684 |
| hybrid chickadees are deficient in learning and memory. | identifying the phenotypes underlying postzygotic reproductive isolation is crucial for fully understanding the evolution and maintenance of species. one potential postzygotic isolating barrier that has rarely been examined is learning and memory ability in hybrids. learning and memory are important fitness-related traits, especially in scatter-hoarding species, where accurate retrieval of hoarded food is vital for winter survival. here, we test the hypothesis that learning and memory ability ca ... | 2018 | 29578575 |
| flexible responses to stage-specific offspring threats. | when caring for their young, parents must compensate for threats to offspring survival in a manner that maximizes their lifetime reproductive success. in birds, parents respond to offspring threats by altering reproductive strategies throughout the breeding attempt. because altered reproductive strategies are costly, when threats to offspring are limited, parents should exhibit a limited response. however, it is unclear if response to offspring threat is the result of an integrated set of correl ... | 2020 | 31993114 |
| flocking propensity by satellites, but not core members of mixed-species flocks, increases when individuals experience energetic deficits in a poor-quality foraging habitat. | mixed-species bird flocks are complex social systems comprising core and satellite members. flocking species are sensitive to habitat disturbance, but we are only beginning to understand how species-specific responses to habitat disturbance affect interspecific associations in these flocks. here we demonstrate the effects of human-induced habitat disturbance on flocking species' behavior, demography, and individual condition within a remnant network of temperate deciduous forest patches in india ... | 2019 | 30625186 |
| nonnative plants reduce population growth of an insectivorous bird. | human-dominated landscapes represent one of the most rapidly expanding and least-understood ecosystems on earth. yet, we know little about which features in these landscapes promote sustainable wildlife populations. historically, in urban areas, landowners have converted native plant communities into habitats dominated by nonnative species that are not susceptible to pest damage and require little maintenance. however, nonnative plants are also poor at supporting insects that are critical food r ... | 2018 | 30348792 |
| spatial extent of mercury contamination in birds and their prey on the floodplain of a contaminated river. | mercury (hg) exposure has been extensively studied in aquatic and piscivorous wildlife, but, historically, less attention has been directed towards terrestrial species. however, it has become apparent that aquatic hg crosses ecosystem boundaries along with beneficial subsidies, thereby entering the terrestrial food chain. it is still not known how far from contaminated waterways hg exposure remains a risk. we examined the spatial extent of exposure in terrestrial songbirds breeding in the floodp ... | 2018 | 29554763 |
| carolina chickadee (poecile carolinensis) calling behavior in response to threats and in flight: flockmate familiarity matters. | signalers can vary their vocal behavior, depending on the presence or absence of conspecific group members, and on the composition of the group. here we asked whether carolina chickadee (poecile carolinensis) signalers varied their vocal behavior, depending on whether they were in the presence of familiar or unfamiliar flockmates. we sorted 32 carolina chickadees into 4 groups with 4 familiar birds each and 4 groups with 4 unfamiliar birds each and recorded their behavior in seminatural aviary s ... | 2018 | 28956937 |