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Daniel Margoliash - One of the best experts on this subject based on the ideXlab platform.
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Automated recognition of bird song elements from continuous recordings using dynamic time warping and hidden Markov models: a comparative study.
Journal of the Acoustical Society of America, 1998Co-Authors: Joseph Kogan, Daniel MargoliashAbstract:The performance of two techniques is compared for automated recognition of bird song units from continuous recordings. The advantages and limitations of dynamic time warping (DTW) and hidden Markov models (HMMs) are evaluated on a large database of male songs of zebra finches (Taeniopygia guttata) and indigo buntings (Passerina cyanea), which have different types of vocalizations and have been recorded under different laboratory conditions. Depending on the quality of recordings and complexity of song, the DTW-based technique gives excellent to satisfactory performance. Under challenging conditions such as noisy recordings or presence of confusing short-duration calls, good performance of the DTW-based technique requires careful selection of templates that may demand expert knowledge. Because HMMs are trained, equivalent or even better performance of HMMs can be achieved based only on segmentation and labeling of constituent vocalizations, albeit with many more training examples than DTW templates. One we...
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Automated bird songs recognition using dynamic time warping and hidden Markov models
Journal of the Acoustical Society of America, 1997Co-Authors: Joseph Kogan, Daniel MargoliashAbstract:The performance of two well‐known recognition techniques in speech adapted to the automated recognition of bird song units from continuous recordings is studied. The advantages and limitations of dynamic time warping (DTW) and hidden Markov models (HMMs) are evaluated on a large database of songs of two species: zebra finches (Taeniopygia guttata) and indigo buntings (Passerina cyanea), which have different types of vocalizations and have been recorded under different laboratory conditions. The recognition performance of these methods is also assessed with regard to song signal representation (including representations commonly used in speech recognition), model structure, and sensitivity. Depending on the quality of recordings and song complexity, the DTW‐based technique gives from excellent to satisfactory results. Under more challenging conditions, such as noisy recordings or the presence in bird vocalizations of confusing transient calls, HMMs can significantly outperform DTW but requires more trainin...
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Template-based automatic recognition of birdsong syllables from continuous recordings
Journal of the Acoustical Society of America, 1996Co-Authors: Sven Anderson, Amish S. Dave, Daniel MargoliashAbstract:The application of dynamic time warping (DTW) to the automated analysis of continuous recordings of animal vocalizations is evaluated. The DTW algorithm compares an input signal with a set of predefined templates representative of categories chosen by the investigator. It directly compares signal spectrograms, and identifies constituents and constituent boundaries, thus permitting the identification of a broad range of signals and signal components. When applied to vocalizations of an indigo bunting (Passerina cyanea) and a zebra finch (Taeniopygia guttata) collected from a low‐clutter, low‐noise environment, the recognizer identifies syllables in stereotyped songs and calls with greater than 97% accuracy. Syllables of the more variable and lower amplitude indigo bunting plastic song are identified with approximately 84% accuracy. Under restricted recording conditions, this technique apparently has general applicability to analysis of a variety of animal vocalizations and can dramatically decrease the amo...
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the process of syllable acquisition in adult indigo buntings Passerina cyanea
Behaviour, 1994Co-Authors: Daniel Margoliash, Cynthia A Staicer, Sue A InoueAbstract:Vocal learning in adult indigo buntings was studied by monitoring socially paired males housed together in sound isolation boxes. Two of three yearlings socially paired with older birds in early spring acquired new syllables and reorganized their stereotyped and plastic songs, while eleven yearlings socially paired later in the year largely failed to acquire new material, as did the older adults socially paired at various times of year. Yearlings changed their stereotyped songs to more closely match their tutors' by replacing syllables or by inserting new syllables. This song matching involved two processes in which adult plastic song played a role: (1) new syllables were developed in plastic song, and (2) newly mastered or pre-existing syllables were transferred from plastic song into stereotyped song. Morphological similarity between yearlings' and tutors' syllables strongly influenced which syllables yearlings retained. After social pairing, matching syllables tended to be delivered more frequently by yearlings and become incorporated into their stereotyped songs, while non-matching syllables tended to decline in use or be discarded altogether. New syllables were formed from existing syllables most morphologically similar to the "target" syllable, through transformation and combination of existing syllables. As new forms became more common, old forms declined and eventually were discarded. Our data suggest that adult indigo buntings maintain the ability to sing stereotyped songs while new material is mastered, and held in reserve, in plastic song. Acquisition of new syllables in yearling indigo buntings requires trial-and-error learning, but proceeds without overproduction and subsequent attrition of distinct syllable types, and does not substantially rely on improvisation and invention. Rather, syllable acquisition and changes to stereotyped songs are strongly influenced by the pre-existing syllable repertoire.
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stereotyped and plastic song in adult indigo buntings Passerina cyanea
Animal Behaviour, 1991Co-Authors: Daniel Margoliash, Cynthia A Staicer, Sue A InoueAbstract:Abstract The vocal behaviour of indigo buntings was studied by monitoring individual males in sound isolation boxes with a computer-assisted system. Yearlings and older adults sang ‘adult plastic’ song as well as stereotyped song. Distinguishing features of adult plastic song include: a larger syllable repertoire; variable syllable order; emphasis of the syllables that appear in the terminal sequence of stereotyped song; a high-frequency ‘S-note’ of variable morphology; calls; occasional production of syllables poorly formed, of intermediate form, or in combination; and low amplitude of delivery. Stereotyped and adult plastic songs were delivered in distinct bouts. Adult plastic songs of indigo buntings share many of the characteristics of early plastic songs of young birds. Several other extended-age learners also exhibit a complex, variable, and low amplitude adult singing behaviour, sometimes described as subsong, in addition to loud stereotyped song. Indigo buntings, and other species that can learn new songs as adults, may retain into adulthood developmental processes that in most species largely terminate with the onset of stereotyped song.
John Faaborg - One of the best experts on this subject based on the ideXlab platform.
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Factors affecting predation at songbird nests in old fields
Journal of Wildlife Management, 2020Co-Authors: Dirk E. Burhans, Frank R. Thompson, Donald C. Dearborn, John FaaborgAbstract:We determined the effects of microhabitat, year, weather, time of season, stage of the nesting cycle, and brood parasitism on nest predation from a 7-year dataset on field sparrows (Spizella pusilla) and indigo buntings (Passerina cyanea) in central Missouri, USA. Year, site, and the interaction of species and 2-week interval of the season were important factors explaining nest predation. The only microhabitat variable that consistently explained predation was nest height: nests over 3 m high almost always fledged. Validation of the model parameters on an independent set of nests resulted in proper categorization (e.g., lost or not lost to predation) of 61.5% of nests. In models testing weather and temporal effects, year was related to daily survival for indigo buntings, and 2-week intervals of the season explained daily survival for both species. Nest predation was higher overall in the nestling stage than in the incubation stage for indigo buntings, and indigo buntings parasitized by brown-headed cowbirds (Molothrus ater) experienced higher predation than nonparasitized buntings. Temporal patterns within the breeding season were consistent between years, and between-year variance appeared to be important, whereas microhabitat was generally unimportant. Research on the mechanisms underlying temporal variability in nest mortality due to predation may identify management options to reduce nest predation.
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Temperature can interact with landscape factors to affect songbird productivity.
Global Change Biology, 2013Co-Authors: Frank R. Thompson, Jennifer L. Reidy, John FaaborgAbstract: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 cover and edge density) on the number of young produced per nest attempt (i.e., productivity) for three species of songbirds. We detected a strong forest cover 9 temperature interaction for the Acadian Flycatcher (Empidonax virescens) on productivity. Greater forest cover resulted in greater productivity because of reduced brood parasitism and increased nest survival, whereas greater temperatures reduced productivity in highly forested landscapes because of increased nest predation but had no effect in less forested landscapes. The Indigo Bunting (Passerina cyanea) exhibited a similar pattern, albeit with a marginal forest cover 9 temperature interaction. By contrast, productivity of the Northern Cardinal (Cardinalis cardinalis) was not influenced by landscape effects or temperature. Our results highlight a potential difficulty of managing wildlife in response to global change such as habitat fragmentation and climate warming, as the habitat associated with the greatest productivity for flycatchers was also that most negatively influenced by high temperatures. The influence of high temperatures on nest predation (and therefore, nest predators) underscores the need to acknowledge the potential complexity of species’ responses to climate change by incorporating a more thorough consideration of community ecology in the development of models of climate impacts on wildlife.
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Landscape forest cover and edge effects on songbird nest predation vary by nest predator
Landscape Ecology, 2012Co-Authors: Frank R. Thompson, John FaaborgAbstract:Rates of nest predation for birds vary between and within species across multiple spatial scales, but we have a poor understanding of which predators drive such patterns. We video-monitored nests and identified predators at 120 nests of the Acadian Flycatcher ( Empidonax virescens ) and the Indigo Bunting ( Passerina cyanea ) at eight study sites in Missouri and Illinois, USA, during 2007–2010. We used an information-theoretic approach to evaluate hypotheses concerning factors affecting predator-specific and overall rates of predation at landscape, edge, and nest-site scales. We found support for effects of landscape forest cover and distance to habitat edge. Predation by Brown-headed Cowbirds ( Molothrus ater ) increased, and predation by rodents decreased as landscape forest cover decreased. Predation by raptors, rodents, and snakes increased as the distance to forest edges decreased, but the effect was modest and conditional upon the top-ranked model. Despite the predator-specific patterns we detected, there was no support for these effects on overall rates of predation. The interactions between breeding birds, nest predators, and the landscapes in which they reside are scale-dependent and context-specific, and may be resistant to broad conceptual management recommendations.
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Species and Temporal Factors Affect Predator-Specific Rates of Nest Predation for Forest Songbirds in the Midwest
The Auk, 2012Co-Authors: Frank R. Thompson, John FaaborgAbstract:ABSTRACT. Knowledge of the relative contributions of predator species to overall rates of nest predation can improve our understanding of why predation risk varies, but the identity of predators is seldom known. We used video technology to identify nest predators of the tree-nesting Acadian Flycatcher (Empidonax virescens) and the shrub-nesting Indigo Bunting (Passerina cyanea) in forests of Missouri and southern Illinois. Raptors, snakes, and nonraptorial birds were the most frequent nest predators; rodents depredated fewer nests; and mesopredators rarely depredated nests. We tested hypotheses concerning effects of songbird species, ordinal date, nest stage, height, and age on overall and predator-specific predation rates to determine whether variation in overall predation rates was attributable to a subset of nest predators. Overall predation rates were higher for Indigo Buntings than for Acadian flycatchers, were higher during the nestling stage than during incubation, and exhibited a midseason peak. C...
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Bird Response to Clear Cutting in Missouri Ozark Forests
Journal of Wildlife Management, 2007Co-Authors: Michael Wallendorf, Paul A. Porneluzi, Wendy K. Gram, Richard L. Clawson, John FaaborgAbstract:Abstract We evaluated changes in breeding bird density and shifts in territory distribution with respect to clear cutting and timber stand improvement (TSI) of even-aged stands on >300 ha experimental management units as part of the Missouri Ozark Forest Ecosystem Project. After one harvest entry, clear cutting had positive effects on density of indigo bunting (Passerina cyanea), prairie warbler (Dendroica discolor), and yellow-breasted chat (Icteria virens) and negative effects on density of Acadian flycatcher (Empidonax virescens), ovenbird (Seiurus aurocapilla), and worm-eating warbler (Helmitheros vermivorus). In buffer regions within 100 m of clearcuts, indigo bunting, hooded warbler (Wilsonia citrina), wood thrush (Hylocichila mustelina), and Kentucky warbler (Oporornis formosus) densities increased and ovenbird density decreased. Breeding bird densities did not change in interior regions >100 m from clearcuts except for a small increase for wood thrush. Breeding Acadian flycatcher and ovenbird show...
Frank R. Thompson - One of the best experts on this subject based on the ideXlab platform.
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Factors affecting predation at songbird nests in old fields
Journal of Wildlife Management, 2020Co-Authors: Dirk E. Burhans, Frank R. Thompson, Donald C. Dearborn, John FaaborgAbstract:We determined the effects of microhabitat, year, weather, time of season, stage of the nesting cycle, and brood parasitism on nest predation from a 7-year dataset on field sparrows (Spizella pusilla) and indigo buntings (Passerina cyanea) in central Missouri, USA. Year, site, and the interaction of species and 2-week interval of the season were important factors explaining nest predation. The only microhabitat variable that consistently explained predation was nest height: nests over 3 m high almost always fledged. Validation of the model parameters on an independent set of nests resulted in proper categorization (e.g., lost or not lost to predation) of 61.5% of nests. In models testing weather and temporal effects, year was related to daily survival for indigo buntings, and 2-week intervals of the season explained daily survival for both species. Nest predation was higher overall in the nestling stage than in the incubation stage for indigo buntings, and indigo buntings parasitized by brown-headed cowbirds (Molothrus ater) experienced higher predation than nonparasitized buntings. Temporal patterns within the breeding season were consistent between years, and between-year variance appeared to be important, whereas microhabitat was generally unimportant. Research on the mechanisms underlying temporal variability in nest mortality due to predation may identify management options to reduce nest predation.
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Songbird Nest Survival in Managed Oak Savannas and Woodlands in the Missouri Ozarks
American Midland Naturalist, 2018Co-Authors: Jennifer L. Reidy, Frank R. ThompsonAbstract:Midwestern savannas and woodlands were once dominant transitional communities but are now considered endangered. Savanna and woodland habitat is being restored and managed throughout the central and east-central portions of the United States, but few studies have investigated the effects of management on songbird nest survival. We monitored songbird nests in managed savanna and woodland sites in southern Missouri from 2009 to 2011 to estimate nest survival and to predict the relationships between nest survival and temporal, vegetation structure, and nest site variables. Daily nest survival was generally higher for the four canopy-nesting species, Acadian flycatcher (Empidonax virescens), blue-gray gnatcatcher (Polioptila caerulea), Eastern wood-pewee (Contopus virens), and summer tanager (Piranga rubra) (0.96-0.98), than the four shrub-nesting species, field sparrow (Spizella pusilla), indigo bunting (Passerina cyanea), prairie warbler (Setophaga discolor), and yellow-breasted chat (Icteria virens) (0.92-0.95), for which we estimated survival rates. In general vegetation structure around the nest had little influence on nest survival, except for canopy cover, which occurred in the top model set for four species. Nest survival of yellow-breasted chats was much higher in areas of lower canopy cover, whereas nest survival of Eastern wood-pewees was moderately lower and indigo buntings and summer tanagers peaked at low and intermediate levels of canopy cover, respectively. Therefore, savanna and woodland management, which tends to open the tree canopy, may benefit some bird species in this forested landscape, particularly those associated with low to intermediate canopy cover.
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Timing of Songbird Nest Predation as Revealed by Video Surveillance
The Wilson Journal of Ornithology, 2016Co-Authors: Ryan A. Gill, Frank R. ThompsonAbstract:ABSTRACT The use of video to monitor nests has increased in frequency over the past 25 years and new research using this technology has shed light on many aspects of the interactions between predators and nesting birds. We used video cameras to describe the timing of nest predation events for Acadian Flycatchers (Empidonax virescens), Indigo Buntings (Passerina cyanea), and other forest-dwelling songbird species. Seventy-four percent (111 of 151) of nest predation events occurred during diurnal hours for both focal species. Although some of our observations were unexpected (e.g., Barred Owls [Strix varia] were primarily diurnal nest predators), many of the predator-specific temporal patterns we observed were consistent with prior knowledge. Understanding diel patterns of nest predation in conjunction with identification of the suite of predators that contribute to overall predation rates will improve our understanding of how birds recognize and respond to the risk of nest predation across ecological and e...
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The Effects of Temperature on Nest Predation by Mammals, Birds, and Snakes
The Auk, 2013Co-Authors: Frank R. Thompson, Jennifer L. ReidyAbstract:Abstract. Understanding how weather influences survival and reproduction is an important component of forecasting how climate change will influence wildlife population viability. Nest predation is the primary source of reproductive failure for passerine birds and can change in response to temperature. However, it is unclear which predator species are responsible for such patterns because predation events are rarely observed. We investigated whether temperature influenced predator-specific rates of nest predation by analyzing data from six prior studies conducted between 1997 and 2010 in Texas, Illinois, and Missouri that used constant-surveillance video systems to identify predators at the nests of Golden-cheeked Warblers (Setophaga chrysoparia), Blackcapped Vireos (Vireo atricapilla), Indigo Buntings (Passerina cyanea), and Acadian Flycatchers (Empidonax virescens). Rates of nest predation by snakes and birds increased as daily maximum temperatures increased, whereas predation by mammals was essentially ...
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Temperature can interact with landscape factors to affect songbird productivity.
Global Change Biology, 2013Co-Authors: Frank R. Thompson, Jennifer L. Reidy, John FaaborgAbstract: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 cover and edge density) on the number of young produced per nest attempt (i.e., productivity) for three species of songbirds. We detected a strong forest cover 9 temperature interaction for the Acadian Flycatcher (Empidonax virescens) on productivity. Greater forest cover resulted in greater productivity because of reduced brood parasitism and increased nest survival, whereas greater temperatures reduced productivity in highly forested landscapes because of increased nest predation but had no effect in less forested landscapes. The Indigo Bunting (Passerina cyanea) exhibited a similar pattern, albeit with a marginal forest cover 9 temperature interaction. By contrast, productivity of the Northern Cardinal (Cardinalis cardinalis) was not influenced by landscape effects or temperature. Our results highlight a potential difficulty of managing wildlife in response to global change such as habitat fragmentation and climate warming, as the habitat associated with the greatest productivity for flycatchers was also that most negatively influenced by high temperatures. The influence of high temperatures on nest predation (and therefore, nest predators) underscores the need to acknowledge the potential complexity of species’ responses to climate change by incorporating a more thorough consideration of community ecology in the development of models of climate impacts on wildlife.
Nikita Chernetsov - One of the best experts on this subject based on the ideXlab platform.
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Further evidence of a time-independent stellar compass in a night-migrating songbird
Behavioral Ecology and Sociobiology, 2017Co-Authors: Alexander Pakhomov, Anna Anashina, Nikita ChernetsovAbstract:We tested whether European robins Erithacus rubecula have a time-independent stellar compass, i.e. whether they can use the stellar pattern for finding the seasonally appropriate migratory direction without reference to their internal clock. It has been claimed earlier on the basis of experiments with other nocturnal migrants, indigo buntings Passerina cyanea , pied flycatchers Ficedula hypoleuca and blackcaps Sylvia atricapilla , but none of the previous experiments was performed in the vertical magnetic field, which rules out the use of the magnetic compass, and under the natural nocturnal sky. We argue that pervious experiments allow alternative interpretations, albeit unlikely. Our data independently confirm that European robins, like other nocturnal passerine migrants hitherto studied, use their stellar compass independently of their internal clock. Significance statement It is generally assumed since the classic experiments of Stephen Emlen performed in the 1960s that star compass of migrating songbirds is time-independent, i.e. that the birds use the pattern of constellations and not the angle of rotation of the starry sky. However, it has not been shown unequivocally, because early experiments did not consider the possibility that the birds relied on magnetic compass rather than on time-independent stellar compass system. Here, we show that stellar compass of European robins tested in the vertical magnetic field that did not provide compass information is indeed independent of the birds’ internal clock and cannot be manipulated by resetting this clock. Cognitive challenges of learning the pattern of constellations, which is necessary to use time-independent star compass, are most fascinating and deserve detailed behavioural and neurobiological study.
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Further evidence of a time-independent stellar compass in a night-migrating songbird
Behavioral Ecology and Sociobiology, 2017Co-Authors: Alexander Pakhomov, Anna Anashina, Nikita ChernetsovAbstract:We tested whether European robins Erithacus rubecula have a time-independent stellar compass, i.e. whether they can use the stellar pattern for finding the seasonally appropriate migratory direction without reference to their internal clock. It has been claimed earlier on the basis of experiments with other nocturnal migrants, indigo buntings Passerina cyanea, pied flycatchers Ficedula hypoleuca and blackcaps Sylvia atricapilla, but none of the previous experiments was performed in the vertical magnetic field, which rules out the use of the magnetic compass, and under the natural nocturnal sky. We argue that pervious experiments allow alternative interpretations, albeit unlikely. Our data independently confirm that European robins, like other nocturnal passerine migrants hitherto studied, use their stellar compass independently of their internal clock. It is generally assumed since the classic experiments of Stephen Emlen performed in the 1960s that star compass of migrating songbirds is time-independent, i.e. that the birds use the pattern of constellations and not the angle of rotation of the starry sky. However, it has not been shown unequivocally, because early experiments did not consider the possibility that the birds relied on magnetic compass rather than on time-independent stellar compass system. Here, we show that stellar compass of European robins tested in the vertical magnetic field that did not provide compass information is indeed independent of the birds’ internal clock and cannot be manipulated by resetting this clock. Cognitive challenges of learning the pattern of constellations, which is necessary to use time-independent star compass, are most fascinating and deserve detailed behavioural and neurobiological study.
Sue A Inoue - One of the best experts on this subject based on the ideXlab platform.
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the process of syllable acquisition in adult indigo buntings Passerina cyanea
Behaviour, 1994Co-Authors: Daniel Margoliash, Cynthia A Staicer, Sue A InoueAbstract:Vocal learning in adult indigo buntings was studied by monitoring socially paired males housed together in sound isolation boxes. Two of three yearlings socially paired with older birds in early spring acquired new syllables and reorganized their stereotyped and plastic songs, while eleven yearlings socially paired later in the year largely failed to acquire new material, as did the older adults socially paired at various times of year. Yearlings changed their stereotyped songs to more closely match their tutors' by replacing syllables or by inserting new syllables. This song matching involved two processes in which adult plastic song played a role: (1) new syllables were developed in plastic song, and (2) newly mastered or pre-existing syllables were transferred from plastic song into stereotyped song. Morphological similarity between yearlings' and tutors' syllables strongly influenced which syllables yearlings retained. After social pairing, matching syllables tended to be delivered more frequently by yearlings and become incorporated into their stereotyped songs, while non-matching syllables tended to decline in use or be discarded altogether. New syllables were formed from existing syllables most morphologically similar to the "target" syllable, through transformation and combination of existing syllables. As new forms became more common, old forms declined and eventually were discarded. Our data suggest that adult indigo buntings maintain the ability to sing stereotyped songs while new material is mastered, and held in reserve, in plastic song. Acquisition of new syllables in yearling indigo buntings requires trial-and-error learning, but proceeds without overproduction and subsequent attrition of distinct syllable types, and does not substantially rely on improvisation and invention. Rather, syllable acquisition and changes to stereotyped songs are strongly influenced by the pre-existing syllable repertoire.
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stereotyped and plastic song in adult indigo buntings Passerina cyanea
Animal Behaviour, 1991Co-Authors: Daniel Margoliash, Cynthia A Staicer, Sue A InoueAbstract:Abstract The vocal behaviour of indigo buntings was studied by monitoring individual males in sound isolation boxes with a computer-assisted system. Yearlings and older adults sang ‘adult plastic’ song as well as stereotyped song. Distinguishing features of adult plastic song include: a larger syllable repertoire; variable syllable order; emphasis of the syllables that appear in the terminal sequence of stereotyped song; a high-frequency ‘S-note’ of variable morphology; calls; occasional production of syllables poorly formed, of intermediate form, or in combination; and low amplitude of delivery. Stereotyped and adult plastic songs were delivered in distinct bouts. Adult plastic songs of indigo buntings share many of the characteristics of early plastic songs of young birds. Several other extended-age learners also exhibit a complex, variable, and low amplitude adult singing behaviour, sometimes described as subsong, in addition to loud stereotyped song. Indigo buntings, and other species that can learn new songs as adults, may retain into adulthood developmental processes that in most species largely terminate with the onset of stereotyped song.