Territory Quality Predicts Avian Vocal Performance Across an Urban-Rural Gradient

Frontiers in Ecology and Evolution, Journal Year: 2020, Volume and Issue: 8

Published: Dec. 23, 2020

Human activity around the globe is a growing source of selection pressure on animal behavior and communication systems. Some animals can modify their vocalizations to avoid masking from anthropogenic noise. However, such modifications also affect salience these in functional contexts as competition mate choice. Such case well-studied Nuttall's white-crowned sparrow ( Zonotrichia leucophrys nuttalli ), which lives year-round both urban San Francisco nearby rural Point Reyes. A performance feature this species' song salient territorial defense, that higher songs elicit stronger responses simulated intrusions; but with lower values transmit better key question then whether vocal signals male quality ability obtain high territories populations. We predicted sparrows will be condition tend hold noise levels more species-preferred landscape features. Because are adapted coastal scrub habitats, we expect contain less dense canopies, drought, greenness, flat open ground for foraging. To test our predictions, recorded measured body (scaled mass index fat score) set birds N = 93), well ambient territories. Remote sensing metrics features territories, drought stress (NDWI), greenness (NDVI), mean canopy height, maximum leaf area density (understory canopy), slope, percent bare 50 m radius each territory. did not find correlation between relationship performance. Further, performers held canopies vegetation, These findings link together fundamental aspects sexual habitat sexually selected appear associated: males have highest performing defending quality.

Language: Английский

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Experimentally broadcast ocean surf and river noise alters birdsong

PeerJ, Journal Year: 2022, Volume and Issue: 10, P. e13297 - e13297

Published: May 17, 2022

Anthropogenic noise and its effects on acoustic communication have received considerable attention in recent decades. Yet, the natural environment’s influence role shaping signals remains unclear. We used large-scale playbacks of ocean surf coastal areas whitewater river riparian to investigate how sounds influences song structure six songbird species. recorded individuals defending territories a variety conditions across 19 study sites California 18 Idaho. Acoustic characteristics included naturally quiet ‘control’ sites, ‘positive control’ that were adjacent or thus noisy, ‘phantom’ playback exposed continuous broadcast low-frequency noise, ‘shifted’ with shifted up frequency. predicted spectral temporal would generally correlate background sound amplitude signal features differ site types based profile environment. found ways which varied acoustics quite variable from species For instance, Idaho both frequency bandwidth duration lazuli bunting ( Passerina amoena ) sparrow Melospiza melodia songs decreased elevated but these unrelated warbling vireo Vireo gilvus ), tended increase minimum maximum amplitude. In California, trill white-crowned Zonotrichia leucophrys amplitude, matching results previous studies involving anthropogenic noise. contrast, wrentit Chamaea fasciata was positively related Although responses heterogeneous, all and/or Collectively, provide strong evidence soundscapes long influenced vocal behavior. More broadly, evolved behavioral long-standing challenges presented by sources likely explain many observed for communicating difficult human-made

Language: Английский

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Song complexity is associated with habitat quality in an upland passerine

Ibis, Journal Year: 2023, Volume and Issue: 166(2), P. 682 - 693

Published: July 18, 2023

Understanding the influence of intrinsic (genetic and morphological) extrinsic (geographical, environmental social) factors on performance spatial differentiation sexual signals, such as bird song, can help identify behavioural indicators individual quality, habitat degradation social environment. We used Iberian Bluethroat Luscinia svecica azuricollis , a migratory that breeds in fragmented landscapes dominated by shrublands, case study to: (1) assess how set acoustic song are driven factors; (2) contrast deterministic (adaptations to context morphological constraints) vs. stochastic (differentiation geographical isolation) explanations for patterns. explored (spectral, temporal complexity) relation parameters related genetic structure, body size, type, quality (assessed through spatially explicit modelling approach) (population abundance songbird community composition). Then, we contribution genetic, dissimilarity diversification across space. Our results highlight an association spectral variables with structure significant connection between complexity duration quality. found no relationship features variables, or distances. There was, however, correlation dissimilarity. recommend consideration indicator

Language: Английский

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The effects of anthropogenic noise and urban habitats on song structure in a vocal mimic; the gray catbird (Dumetella carolinensis) sings higher frequencies in noisier habitats

Frontiers in Ecology and Evolution, Journal Year: 2023, Volume and Issue: 11

Published: Dec. 20, 2023

In urban and human-modified landscapes, animals face novel selection pressures resulting from differences in habitat structure increased anthropogenic noise. Urban noise pollution can negatively impact songbirds because low-frequency often masks portions of birds’ mating signals reduces signal transmission. Previous research has demonstrated that the songs birds more habitats have structural enhance transmission when is present. The majority these studies focused on species deliver short, stereotyped limited repertoires. Gray catbirds ( Dumetella carolinensis , family: Mimidae) sing long bouts containing imitated, improvised, invented song elements, therefore may an ability to vary response We hypothesized aspects developed including loud changes land cover would catbirds’ parameters, minimum, peak, maximum frequency, frequency bandwidth, entropy. recorded processed 42 male analyzed over 18,000 elements sites along gradient western Virginia Washington, DC metropolitan region. quantified intensity at each site-centroid based percent canopy cover, impervious surface, level. Song features such as maximum, peak significantly levels increased, demonstrating noisier areas higher compared individuals quieter habitats. Land variables also predicted certain (impervious surface) or entropy (canopy cover). These catbird limit negative effects environmental noise-masking, even for their bouts, suggest vocal mimics respond Future could investigate repertoire size composition if lead functional consequences mimics.

Language: Английский

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Savanna Nightjars (Caprimulgus affinis stictomus) adjust calling height to gain amplitude advantage in urban environments

Journal of Ornithology, Journal Year: 2024, Volume and Issue: 165(3), P. 627 - 635

Published: Jan. 31, 2024

Language: Английский

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The Acoustic adaptation hypothesis does not support the occurrence of common songs in a neotropical urban bird species

Bioacoustics, Journal Year: 2024, Volume and Issue: 33(6), P. 510 - 526

Published: Nov. 1, 2024

The Acoustic Adaptation Hypothesis indicates that vocalisations will have acoustic characteristics maximise their transmission within the habitat where they are produced. Therefore, of same species expected to vary between habitats if in structure. We conducted a sound experiment analyse common songs White-eared ground sparrow, Melozone leucotis, an urban bird species, differ populations because adapted each transmission. was four isolated areas Costa Rica with different habitats: secondary forests, coffee plantations, gardens and thickets. In population, we reproduced three compared song degradation measures (excess attenuation, blur ratio, signal-to-noise tail-to-signal ratio). Contrary our expectations, results contradicted Hypothesis, since population did not transmit better own habitat, but original habitat. suggest this may be selected maintained by female selection.

Language: Английский

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Time alters urban singing strategies in a North American songbird

Journal of Urban Ecology, Journal Year: 2023, Volume and Issue: 9(1)

Published: Jan. 1, 2023

Abstract Local habitats shape animal vocalizations through selection to improve transmission of signals receivers. This process can be variable, however, when landscapes are changing continuously due urbanization or other factors. Studies have shown that some birds alter the frequency, amplitude and structure their songs in urban habitats. Because songbirds learn from individuals, this cultural result substantial change over time. Urban bird populations may therefore show rapid shifts song form variation combined interacting effects time anthropogenic habitat change. In study, we used historic recent recordings investigate changes spotted towhee (Pipilo maculatus) 45 years across an urban-to-rural gradient northern California. We found pre-trill trilled parts covaried differently with development at two time-points, more occurring trill phrases than pre-trills. Additionally, 1970 adjusted trills areas by raising maximum frequencies broadening bandwidths, while 2015 narrowed bandwidths decreasing areas. These results did not fit our prediction would a consistent effect on time-points. suggest habitat, evolution drift act elements complicated ways vary

Language: Английский

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Song and genetic divergence within a subspecies of white-crowned sparrow (Zonotrichia leucophrys nuttalli)

PLoS ONE, Journal Year: 2024, Volume and Issue: 19(5), P. e0304348 - e0304348

Published: May 29, 2024

Animal culture evolves alongside genomes, and the two modes of inheritance-culture genes-interact in myriad ways. For example, stable geographic variation can act as a reproductive barrier, thereby facilitating genetic divergence between "cultural populations." White-crowned sparrows (Zonotrichia leucophrys) are well-established model species for bird song learning cultural evolution, they have distinct, geographically discrete, culturally transmitted types (i.e., dialects). In this study, we tested hypothesis that songs drives within Nuttall's white-crowned (Z. l. nuttalli). accordance with sexual selection theory, hypothesized mating signals both preceded generated divergence. We characterized population structure subspecies found genetically differentiated populations whose boundary coincides major at Monterey Bay, California. then conducted playback experiment demonstrated males discriminate based on their degree from local dialect. These results support idea discrimination against non-local is driving northern southern populations. Altogether, study provides evidence foundation speciation by selection.

Language: Английский

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Comparative bioacoustics of multiple eastern versus western songbird pairs in North America reveals a gradient of song divergence

PLoS ONE, Journal Year: 2024, Volume and Issue: 19(12), P. e0312706 - e0312706

Published: Dec. 26, 2024

Vocalizations are one of the key premating reproductive barriers that could affect species formation. In song-learning birds, vocal traits sometimes overlooked in delimitation, as compared to morphological or plumage-based differences. this study, we assessed geographic variation songs eight pairs oscines on two scales: (1) comparing primary species/subspecies whose breeding grounds eastern and western counterparts each other continental North America, (2) for counterpart, identifying possible among their populations. We found there were strong differences between taxa, though magnitude difference was not correlated a mitochondrial DNA-based estimates divergence. Additionally, within-taxa common our focal beyond single (Townsend’s warbler, Setophaga townsendi ). The result study provides standardized, quantitative comparison songbirds, serves foundation explore effectiveness vocalizations barrier at scale.

Language: Английский

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Urban cycles of human activity do not significantly alter the behaviour of a duetting bird

Ibis, Journal Year: 2021, Volume and Issue: 163(4), P. 1394 - 1408

Published: March 30, 2021

The weekend effect hypothesis predicts that weekly cycles of human activity impact animal behaviour and physiology. This has been supported in the context recreational natural environments but it is unknown whether also applies to urban animals. We tested this by comparing sentinel (territorial vigilance), foraging vocal behaviours an urban‐dwelling bird, Rufous Hornero Furnarius rufus, between weekdays weekends (and holidays) within a university campus central Brazil. level (noise, traffic pedestrian flow) increases greatly on campus. predicted birds would perceive greater predation risk need adjust their acoustic signals response anthropogenic noise weekdays. Thus, we expected spend more time as sentinels less foraging, sing for longer periods at higher pitch than weekends. weaker duet responsiveness (answering partner‐initiated song) noisier weekends, assuming disrupt signal transmission partners. found spent slightly (˜ 4%) 2–5%) these effects were small not statistically significant. Birds equally likely solos, start duets answer Finally, phrase duration parameters similar Our results provide little support hypothesis, suggesting may be habituated or indifferent periodic variation levels.

Language: Английский

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