Avian Research最新文献_第2页

Three subspecies of Black-tailed Godwit share non-breeding sites in the world's largest river delta

IF 1.6 2区生物学 Q1 ORNITHOLOGY

Avian Research

Pub Date : 2025-02-10 DOI: 10.1016/j.avrs.2025.100226

Delip K. Das , Wouter M.G. Vansteelant , Bingrun Zhu , Shariful Islam , Naim Khandakar , Marco van der Velde , Chris J. Hassell , Jesse R. Conklin , Pierrick Bocher , Jos C.E.W. Hooijmeijer , Yvonne I. Verkuil , Theunis Piersma

During the non-breeding season (September–April), Black-tailed Godwits (Limosa limosa) are commonly seen in coastal and inland wetlands of the Ganges-Brahmaputra-Meghna Delta in Bangladesh. We hypothesize that the Ganges-Brahmaputra-Meghna Delta, at the overlap between the Central Asian and East Asian–Australasian flyways, may host three subspecies that breed in disjunct areas of temperate and northern Asia: L. l. limosa, L. l. melanuroides, and L. l. bohaii. We used mitochondrial DNA (mtDNA) haplotype network and biometric analysis to determine subspecies in captured individuals, and deployed GPS–GSM transmitters to verify breeding areas of individuals with subspecies assignments. To test for differential habitat preferences, we sampled birds at two ecologically distinct habitats known to host the largest concentrations of non-breeding Black-tailed Godwits in Bangladesh: Nijhum Dweep National Park, a tidal coastal habitat with brackish water on the south-central coast, and Tanguar Haor (‘backmarsh’), a seasonal freshwater floodplain in the north. During the non-breeding seasons of 2021–2022 and 2022–2023, we sampled and measured 93 Black-tailed Godwits, 54 of which were equipped with GPS–GSM transmitters. Our mtDNA haplotype network analysis confirmed the presence of limosa, melanuroides, and bohaii subspecies at the study sites. Thus, indeed, Black-tailed Godwits subspecies, despite having distinct breeding ranges, exhibit (partially) overlapping non-breeding ranges in Asia. The subspecies composition differed significantly between sites, with limosa and bohaii dominating in Tanguar Haor and melanuroides in Nijhum Dweep. Of the 21 individuals that were tracked to their breeding grounds, 18 migrated to the expected breeding range of their respective subspecies. However, one bird with a limosa haplotype migrated to a known breeding area of bohaii, whereas two birds with melanuroides haplotypes migrated to the supposed breeding range of limosa. Therefore, while ecological factors at both ends of the flyways may shape the morphological and behavioural differences between Black-tailed Godwit subspecies, their delineations and possible gene flow require further studies.

{"title":"Three subspecies of Black-tailed Godwit share non-breeding sites in the world's largest river delta","authors":"Delip K. Das , Wouter M.G. Vansteelant , Bingrun Zhu , Shariful Islam , Naim Khandakar , Marco van der Velde , Chris J. Hassell , Jesse R. Conklin , Pierrick Bocher , Jos C.E.W. Hooijmeijer , Yvonne I. Verkuil , Theunis Piersma","doi":"10.1016/j.avrs.2025.100226","DOIUrl":"10.1016/j.avrs.2025.100226","url":null,"abstract":"<div><div>During the non-breeding season (September–April), Black-tailed Godwits (<em>Limosa limosa</em>) are commonly seen in coastal and inland wetlands of the Ganges-Brahmaputra-Meghna Delta in Bangladesh. We hypothesize that the Ganges-Brahmaputra-Meghna Delta, at the overlap between the Central Asian and East Asian–Australasian flyways, may host three subspecies that breed in disjunct areas of temperate and northern Asia: <em>L. l. limosa</em>, <em>L. l. melanuroides</em>, and <em>L. l. bohaii</em>. We used mitochondrial DNA (mtDNA) haplotype network and biometric analysis to determine subspecies in captured individuals, and deployed GPS–GSM transmitters to verify breeding areas of individuals with subspecies assignments. To test for differential habitat preferences, we sampled birds at two ecologically distinct habitats known to host the largest concentrations of non-breeding Black-tailed Godwits in Bangladesh: Nijhum Dweep National Park, a tidal coastal habitat with brackish water on the south-central coast, and Tanguar Haor (‘backmarsh’), a seasonal freshwater floodplain in the north. During the non-breeding seasons of 2021–2022 and 2022–2023, we sampled and measured 93 Black-tailed Godwits, 54 of which were equipped with GPS–GSM transmitters. Our mtDNA haplotype network analysis confirmed the presence of <em>limosa</em>, <em>melanuroides</em>, and <em>bohaii</em> subspecies at the study sites. Thus, indeed, Black-tailed Godwits subspecies, despite having distinct breeding ranges, exhibit (partially) overlapping non-breeding ranges in Asia. The subspecies composition differed significantly between sites, with <em>limosa</em> and <em>bohaii</em> dominating in Tanguar Haor and <em>melanuroides</em> in Nijhum Dweep. Of the 21 individuals that were tracked to their breeding grounds, 18 migrated to the expected breeding range of their respective subspecies. However, one bird with a <em>limosa</em> haplotype migrated to a known breeding area of <em>bohaii</em>, whereas two birds with <em>melanuroides</em> haplotypes migrated to the supposed breeding range of <em>limosa</em>. Therefore, while ecological factors at both ends of the flyways may shape the morphological and behavioural differences between Black-tailed Godwit subspecies, their delineations and possible gene flow require further studies.</div></div>","PeriodicalId":51311,"journal":{"name":"Avian Research","volume":"16 1","pages":"Article 100226"},"PeriodicalIF":1.6,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143422402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

How does asymmetric sibling rivalry respond under environmental metal pollution? A case study of the Tree Sparrow (Passer montanus)

IF 1.6 2区生物学 Q1 ORNITHOLOGY

Avian Research

Pub Date : 2025-01-27 DOI: 10.1016/j.avrs.2025.100225

Jian Ding , Shengnan Wang , Wenzhi Yang , Huijie Zhang , Ni Wang , Yingmei Zhang

The imbalanced allocation of maternal resources to eggs and nestlings may significantly impact the phenotype and fitness of offspring. Moreover, anthropogenic metal pollution has been reported to exert adverse effects on avian offspring. Therefore, we herein evaluated the relationships among offspring characteristics, asymmetric sibling rivalry, and the resulting offspring phenotype in a small passerine bird, Tree Sparrow (Passer montanus), at a polluted site (Baiyin, BY) and a relatively unpolluted site (Liujiaxia, LJX). By initiating incubation before the completion of clutch, asymmetric sibling rivalry might create a core and marginal offspring within the brood. In this study, lower egg mass, fewer core offspring, and more marginal offspring were found at the polluted site. Although eggshell speckling and coloration were relatively similar between the two sites, higher eggshell spotting coverage ratio and lower eggshell lightness (L∗) and hue (h°) were observed in core eggs than in marginal eggs at the unpolluted site. The clutch size had a positive relationship with egg mass at the polluted site and with brood size at hatching at the unpolluted site. The differences in egg measurements across the laying orders in the samples were relatively large for larger clutch sizes. The core and marginal egg masses had a significant positive effect on the size of early core nestlings and late marginal nestlings at the unpolluted site. Fledgling rate was significantly positively related to the incubation period and nestling period, while negative relationship with mean spotting coverage ratio was found at the polluted site. Marginal nestlings at the polluted site showed a higher mortality rate. Overall, although asymmetric sibling competition strongly determines the variation of marginal offspring size, the effect is less dramatic in metal-polluted environments, providing some respite to wild birds that survive pollution-induced stress.

{"title":"How does asymmetric sibling rivalry respond under environmental metal pollution? A case study of the Tree Sparrow (Passer montanus)","authors":"Jian Ding , Shengnan Wang , Wenzhi Yang , Huijie Zhang , Ni Wang , Yingmei Zhang","doi":"10.1016/j.avrs.2025.100225","DOIUrl":"10.1016/j.avrs.2025.100225","url":null,"abstract":"<div><div>The imbalanced allocation of maternal resources to eggs and nestlings may significantly impact the phenotype and fitness of offspring. Moreover, anthropogenic metal pollution has been reported to exert adverse effects on avian offspring. Therefore, we herein evaluated the relationships among offspring characteristics, asymmetric sibling rivalry, and the resulting offspring phenotype in a small passerine bird, Tree Sparrow (<em>Passer montanus</em>), at a polluted site (Baiyin, BY) and a relatively unpolluted site (Liujiaxia, LJX). By initiating incubation before the completion of clutch, asymmetric sibling rivalry might create a core and marginal offspring within the brood. In this study, lower egg mass, fewer core offspring, and more marginal offspring were found at the polluted site. Although eggshell speckling and coloration were relatively similar between the two sites, higher eggshell spotting coverage ratio and lower eggshell lightness (<em>L</em>∗) and hue (<em>h</em>°) were observed in core eggs than in marginal eggs at the unpolluted site. The clutch size had a positive relationship with egg mass at the polluted site and with brood size at hatching at the unpolluted site. The differences in egg measurements across the laying orders in the samples were relatively large for larger clutch sizes. The core and marginal egg masses had a significant positive effect on the size of early core nestlings and late marginal nestlings at the unpolluted site. Fledgling rate was significantly positively related to the incubation period and nestling period, while negative relationship with mean spotting coverage ratio was found at the polluted site. Marginal nestlings at the polluted site showed a higher mortality rate. Overall, although asymmetric sibling competition strongly determines the variation of marginal offspring size, the effect is less dramatic in metal-polluted environments, providing some respite to wild birds that survive pollution-induced stress.</div></div>","PeriodicalId":51311,"journal":{"name":"Avian Research","volume":"16 1","pages":"Article 100225"},"PeriodicalIF":1.6,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143395148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Local song evolution after three decades in a complex songster, the Thrush Nightingale

IF 1.6 2区生物学 Q1 ORNITHOLOGY

Avian Research

Pub Date : 2025-01-27 DOI: 10.1016/j.avrs.2025.100224

Abel Souriau , Jorma Sorjonen , Adam Petrusek , Tereza Petrusková

Birdsong is an important secondary sexual trait which may vary between but also within species. Intraspecific variation is generally studied either on the geographical or on the temporal scale; most of the studies exploring the variation of song over time, however, focused on species with rather simple songs. In this study, we explored the temporal changes in song of a complex songster, the Thrush Nightingale (Luscinia luscinia), recorded after 33 years (in 1986 and 2019) at the same locality in south-eastern Finland. Our analysis revealed a complete turnover of song types over the study period, with no song type shared between the two recording years. In contrast, 40% of the originally recorded syllable types were still found in the repertoires of recently recorded males. Their song type repertoires were significantly smaller but the songs themselves were on average longer compared to the 1986 recordings. Repertoires of both syllables and song types were more shared between males recorded in 1986 than between those from 2019. We discuss the processes that may have contributed to these temporal changes in song and call for more detailed studies of song evolution in wild populations.

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引用次数: 0

Inter- and intraspecific variation in flight muscle fibers is associated with migratory timing

IF 1.6 2区生物学 Q1 ORNITHOLOGY

Avian Research

Pub Date : 2025-01-22 DOI: 10.1016/j.avrs.2025.100223

Shangmingyu Zhang , Shane DuBay , Yuwen Cheng , Zhehan Dong , Zhengwei Liu , Yongjie Wu

The life-history strategies of organisms are shaped by trade-offs among traits that influence survival, development, reproduction, and ultimately fitness. However, the specific physiological and environmental mechanisms driving population-level variation in phenotypic traits, particularly in relation to migratory adaptations, remain poorly understood. Elevational migration represents an adaptive behavior for mountain birds that offers a unique model to investigate adaptive phenotypes because of the diverse migratory strategies that have been observed within and between species. Flight muscles, as multifunctional organs, exhibit phenotypic variation that aligns with locomotor and thermoregulatory demands. Linking flight muscle phenotypes to migratory strategies can provide insights into inter- and intraspecific variation in migratory adaptations. In this study, we examined spring arrival dates at high-altitude breeding sites for three closely related high-altitude breeding birds in the mountains of Asia: Blue-fronted Redstart (Phoenicurus frontalis), Himalayan Bluetail (Tarsiger rufilatus), and Rufous-gorgeted Flycatcher (Ficedula strophiata). We analyzed relationships between arrival dates and phenotypic traits, including flight muscle physiology, morphology, and internal organ mass, alongside environmental effects on these traits. Our findings indicate that species arriving earlier encountered lower temperatures and exhibited reduced fiber cross-sectional areas coupled with higher fast oxidative glycolytic (FOG) fibers densities. Males displayed pronounced protandry and higher fast glycolytic (FG) fibers densities. Ambient temperature significantly influenced flight muscle phenotypes, highlighting intraspecific variation and the potential plasticity of flight muscle fibers as crucial mechanisms for adapting to migration strategies and environmental conditions. Additionally, this study underscores the potential role of sexual selection in shaping functional phenotypic variation, further advancing our understanding of adaptive strategies in high-altitude migratory birds.

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引用次数: 0

Distribution pattern and niche overlap of sympatric breeding birds along human-modified habitat gradients in Inner Mongolia, China

IF 1.6 2区生物学 Q1 ORNITHOLOGY

Avian Research

Pub Date : 2025-01-20 DOI: 10.1016/j.avrs.2025.100222

Xi Yang , Lishi Zhang , Piotr Tryjanowski , Frédéric Jiguet , Zheng Han , Haitao Wang

The transformation of natural habitats into human-modified landscapes has far-reaching consequences for species distribution and abundance. As species adapt to these changing environments, shifts in distribution patterns, niche dynamics, and interspecies interactions may occur, impacting biodiversity at multiple levels and potentially leading to ecosystem imbalances. This study aims to assess the impact of variations in vegetation composition and human disturbance on the distribution of sympatric breeding birds and to determine the extent of niche overlap or differentiation among these species. We conducted field surveys and collected data on bird distribution, vegetation composition, and level of human disturbance in eastern Inner Mongolian grasslands. We focused on the six most frequently co-occurring breeding birds, representing a mix of sparrows, larks, and corvids. Generalized Additive Models revealed varying responses of species occurrence along habitat gradients. Species like the Eurasian Skylark (Alauda arvensis), Mongolian Lark (Melanocorypha mongolica), and Asian Short-toed Lark (Calandrella cheleensis), increased in larger and more connected habitats, while others, like the Tree Sparrow (Passer montanus), Eurasian Magpie (Pica pica), and Barn Swallow (Hirundo rustica), adapted to more fragmented habitats. Niche analysis indicated habitat generalists tended to occupy larger niches than grassland specialists. Substantial niche overlap was also found among the six co-occurring bird species. Conservation efforts should consider the specific needs of specialist species and strive to maintain or restore critical grassland habitats. Additionally, promoting sustainable agricultural practices that balance the needs of birds and human activities can contribute to the coexistence of generalist and specialist bird species in modified landscapes.

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引用次数: 0

Assessing the vulnerability of wintering habitats for the red-listed Asian Houbara (Chlamydotis macqueenii) using climate models and human impact assessments

IF 1.6 2区生物学 Q1 ORNITHOLOGY

Avian Research

Pub Date : 2024-12-17 DOI: 10.1016/j.avrs.2024.100221

Gulzaman William , Zafeer Saqib , Abdul Qadir , Nisha Naeem , Mehrban Ali Brohi , Asim Kamran , Afia Rafique

The Asian Houbara (Chlamydotis macqueenii), a vulnerable species, is under significant threat from habitat degradation and anthropogenic pressures in Pakistan's arid landscapes. This study addresses the urgent need for conservation by identifying critical habitats, analyzing the influence of environmental and human factors on species distribution, and projecting future habitat shifts under climate change scenarios. Using the MaxEnt model, which achieves a robust predictive accuracy (AUC = 0.854), we mapped current and future habitat suitability under Shared Socioeconomic Pathways (SSP126, SSP370, SSP585) for the years 2040 and 2070. Presently, the suitable habitat extends over 217,082 km², with 52,751 km² classified as highly suitable. Key environmental drivers, identified via the Jackknife test, revealed that annual mean temperature (Bio1) and slope play a dominant role in determining habitat suitability. Projections show significant habitat degradation; however, under SSP585, highly suitable areas are expected to expand by up to 24.92% by 2070. Despite this increase, vast areas remain unsuitable, posing serious risks to population sustainability. Moreover, only 2115 km² of highly suitable habitat currently falls within protected zones, highlighting a critical conservation shortfall. These findings highlight the imperative for immediate, targeted conservation efforts to secure the species' future in Pakistan's desert ecosystems.

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引用次数: 0

Decreased basal thermogenesis is associated with the downregulation of cellular metabolic activity of organs and serum thyroid hormones in fasting Eurasian Tree Sparrows (Passer montanus)

IF 1.6 2区生物学 Q1 ORNITHOLOGY

Avian Research

Pub Date : 2024-12-08 DOI: 10.1016/j.avrs.2024.100220

Hong Jin , Qi Xia , Ziqing Gao , Yujie XuanYuan , Beibei Dong , Ming Li , Qingjian Liang , Jinsong Liu

Food is a critical environmental factor that influences animal survival, especially for small passerines due to their high mass-specific metabolic rates. Basal metabolic rate (BMR) reflects the energy expended by endothermic animals for basic physiological processes and constitutes a major part of their daily energy budget. Some birds have been shown to employ compensatory mechanisms during food shortages, temporarily reducing these self-maintenance expenditures without using hypothermia. However, the mechanisms of BMR adjustment remain unexplored. In the present study, we assessed the phenotypic variation in basal thermogenesis of Eurasian Tree Sparrows (Passer montanus) by comparing a control group to groups fasted for 6, 12, 18, and 24 h. We focused on the correlation between a reduction in energy metabolism and the alterations of cellular metabolic activities, mitochondrial substrate supply, and changes in serum thyroid hormones during fasting. Our data indicated that fasting groups had significantly lower body mass, BMR, body temperature, and body fat content. Furthermore, fasting groups had significantly lower glycogen levels, mitochondrial state 4 respiration and cytochrome c oxidase (CCO) activity in the liver, and CCO activity in pectoral muscle. The levels of avian uncoupling protein (av-UCP) mRNA were significantly reduced, while the levels of myostatin protein in pectoral muscle were significantly increased in the fasting groups. Furthermore, the groups subjected to fasting exhibited significantly lower levels of serum glucose, triglyceride, thyroxine (T₄), and triiodothyronine (T₃). Positive correlations were observed between the following pairs of variables: log BMR and log body mass, log body mass and log body fat, log BMR and log state 4 respiration in the liver, log BMR and log CCO activity in the liver and muscle, log BMR and log av-UCP mRNA expression, whereas a negative correlation was observed between log BMR and log myostatin level. In addition, a positive correlation was also detected between log T₃ and each of the following: log BMR, state 4 respiration, and log CCO activity in the liver. Our results suggested that decreased metabolic thermogenesis via down-regulation in cellular aerobic capacity of organs and serum thyroid hormones may be an important survival strategy for fasting Tree Sparrows to reduce energy expenditure.

{"title":"Decreased basal thermogenesis is associated with the downregulation of cellular metabolic activity of organs and serum thyroid hormones in fasting Eurasian Tree Sparrows (Passer montanus)","authors":"Hong Jin , Qi Xia , Ziqing Gao , Yujie XuanYuan , Beibei Dong , Ming Li , Qingjian Liang , Jinsong Liu","doi":"10.1016/j.avrs.2024.100220","DOIUrl":"10.1016/j.avrs.2024.100220","url":null,"abstract":"<div><div>Food is a critical environmental factor that influences animal survival, especially for small passerines due to their high mass-specific metabolic rates. Basal metabolic rate (BMR) reflects the energy expended by endothermic animals for basic physiological processes and constitutes a major part of their daily energy budget. Some birds have been shown to employ compensatory mechanisms during food shortages, temporarily reducing these self-maintenance expenditures without using hypothermia. However, the mechanisms of BMR adjustment remain unexplored. In the present study, we assessed the phenotypic variation in basal thermogenesis of Eurasian Tree Sparrows (<em>Passer montanus</em>) by comparing a control group to groups fasted for 6, 12, 18, and 24 h. We focused on the correlation between a reduction in energy metabolism and the alterations of cellular metabolic activities, mitochondrial substrate supply, and changes in serum thyroid hormones during fasting. Our data indicated that fasting groups had significantly lower body mass, BMR, body temperature, and body fat content. Furthermore, fasting groups had significantly lower glycogen levels, mitochondrial state 4 respiration and cytochrome <em>c</em> oxidase (CCO) activity in the liver, and CCO activity in pectoral muscle. The levels of avian uncoupling protein (<em>av-UCP</em>) mRNA were significantly reduced, while the levels of myostatin protein in pectoral muscle were significantly increased in the fasting groups. Furthermore, the groups subjected to fasting exhibited significantly lower levels of serum glucose, triglyceride, thyroxine (T<sub>4</sub>), and triiodothyronine (T<sub>3</sub>). Positive correlations were observed between the following pairs of variables: log BMR and log body mass, log body mass and log body fat, log BMR and log state 4 respiration in the liver, log BMR and log CCO activity in the liver and muscle, log BMR and log <em>av-UCP</em> mRNA expression, whereas a negative correlation was observed between log BMR and log myostatin level. In addition, a positive correlation was also detected between log T<sub>3</sub> and each of the following: log BMR, state 4 respiration, and log CCO activity in the liver. Our results suggested that decreased metabolic thermogenesis via down-regulation in cellular aerobic capacity of organs and serum thyroid hormones may be an important survival strategy for fasting Tree Sparrows to reduce energy expenditure.</div></div>","PeriodicalId":51311,"journal":{"name":"Avian Research","volume":"16 1","pages":"Article 100220"},"PeriodicalIF":1.6,"publicationDate":"2024-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143098987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Are urbanization, biotic and social factors associated with the song frequency and song entropy attributes of three urban syntopic passerines?

IF 1.6 2区生物学 Q1 ORNITHOLOGY

Avian Research

Pub Date : 2024-12-06 DOI: 10.1016/j.avrs.2024.100219

Xhareni Díaz-Lezama , Alejandro Ariel Ríos-Chelén , Jorge Castellanos-Albores , Paula L. Enríquez

Urban environments have challenging characteristics for bird acoustic communication. High levels of anthropogenic noise, as well as vegetation structure (e.g., in urban parks), can potentially affect the song frequency characteristics of several bird species. An additional factor such as the abundance of conspecific and heterospecific vocalizing birds may play an important role in determining the structure of bird songs. In this study, we analyzed whether noise levels, vegetation percentage, and abundance of conspecifics and heterospecifics influence the song characteristics of three syntopic songbird species: House Finch (Haemorhous mexicanus), Rufous-collared Sparrow (Zonotrichia capensis), and House Sparrow (Passer domesticus) living in urban sites. We recorded songs of these species and measured the peak frequency and entropy of their songs at 14 sites in the city of San Cristobal de Las Casas, Chiapas, Mexico. We found that the song peak frequency of House Finch and House Sparrow's songs was negatively related to the vegetation. The peak frequency of neither of the three species correlated with the average noise level. However, the abundances of conspecific and heterospecific were related to the peak frequency of the three species' songs. The entropy of the House Finch and House Sparrow songs was positively and negatively related, respectively, to noise levels. House Sparrow song entropy was negatively related to the percentage of vegetation. Song entropy of House Finches was negatively associated to conspecific and House Sparrow abundance. Song entropy of Rufous-collared Sparrows was positively related to conspecific abundance. In conclusion, the song peak frequency and song entropy of the three songbird species were differentially related to urban noise, vegetation, and conspecific and heterospecific abundance, suggesting these factors influence bird song characteristics.

{"title":"Are urbanization, biotic and social factors associated with the song frequency and song entropy attributes of three urban syntopic passerines?","authors":"Xhareni Díaz-Lezama , Alejandro Ariel Ríos-Chelén , Jorge Castellanos-Albores , Paula L. Enríquez","doi":"10.1016/j.avrs.2024.100219","DOIUrl":"10.1016/j.avrs.2024.100219","url":null,"abstract":"<div><div>Urban environments have challenging characteristics for bird acoustic communication. High levels of anthropogenic noise, as well as vegetation structure (e.g., in urban parks), can potentially affect the song frequency characteristics of several bird species. An additional factor such as the abundance of conspecific and heterospecific vocalizing birds may play an important role in determining the structure of bird songs. In this study, we analyzed whether noise levels, vegetation percentage, and abundance of conspecifics and heterospecifics influence the song characteristics of three syntopic songbird species: House Finch (<em>Haemorhous mexicanus</em>), Rufous-collared Sparrow (<em>Zonotrichia capensis</em>), and House Sparrow (<em>Passer domesticus</em>) living in urban sites. We recorded songs of these species and measured the peak frequency and entropy of their songs at 14 sites in the city of San Cristobal de Las Casas, Chiapas, Mexico. We found that the song peak frequency of House Finch and House Sparrow's songs was negatively related to the vegetation. The peak frequency of neither of the three species correlated with the average noise level. However, the abundances of conspecific and heterospecific were related to the peak frequency of the three species' songs. The entropy of the House Finch and House Sparrow songs was positively and negatively related, respectively, to noise levels. House Sparrow song entropy was negatively related to the percentage of vegetation. Song entropy of House Finches was negatively associated to conspecific and House Sparrow abundance. Song entropy of Rufous-collared Sparrows was positively related to conspecific abundance. In conclusion, the song peak frequency and song entropy of the three songbird species were differentially related to urban noise, vegetation, and conspecific and heterospecific abundance, suggesting these factors influence bird song characteristics.</div></div>","PeriodicalId":51311,"journal":{"name":"Avian Research","volume":"16 1","pages":"Article 100219"},"PeriodicalIF":1.6,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143098991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Inability of recognizing offspring underlies parental errors in the selection of offspring

IF 1.6 2区生物学 Q1 ORNITHOLOGY

Avian Research

Pub Date : 2024-11-30 DOI: 10.1016/j.avrs.2024.100218

Lifang Gao , Wen Zhang , Wenjing Zhu , Yichen Wu , Ran Xu , Ningning Sun , Yujie Wang , Biyun Jia , Bo Du

Inclusive fitness theory posits that altruistic behaviors, which are directed more likely towards relatives, should be favored by natural selection. However, the prevalence of alternative parenting behaviors in offspring selection, including rejecting their own offspring and accepting the offspring of others, remains poorly understood within the context of parental care evolution. In order to investigate the factors that prompt the occurrence of alternative parenting behaviors, we designed a series of experiments in the Azure-winged Magpie (Cyanopica cyanus). By manipulating the nest spatial position or offspring age/number and parent-offspring familiarity, we addressed how parents provided parental care for the manipulated offspring. In the nest resettlement experiment, the probability of parents rejecting their own offspring significantly increased with nest-moving distances while decreased with offspring ages. In the cross-fostering experiments, the probability of parents provisioning unrelated young significantly decreased with the age difference between cross-fostered chicks. In the nest duplication experiments, where parents were given a choice between familiar offspring and unfamiliar unrelated chicks or between unfamiliar offspring and familiar unrelated chicks, the probability of both alternative parenting behaviors was significantly influenced by the time when parental association with their offspring was deprived. We conclude that as offspring phenotypic traits become individualized and fixed at a special developmental stage, parents gradually acquire the capacity for offspring recognition by associating with them. Any factors that disrupt parent–offspring association or introduce unrelated young into the nest prior to this critical timeline can result in the occurrence of alternative parenting behaviors.

{"title":"Inability of recognizing offspring underlies parental errors in the selection of offspring","authors":"Lifang Gao , Wen Zhang , Wenjing Zhu , Yichen Wu , Ran Xu , Ningning Sun , Yujie Wang , Biyun Jia , Bo Du","doi":"10.1016/j.avrs.2024.100218","DOIUrl":"10.1016/j.avrs.2024.100218","url":null,"abstract":"<div><div>Inclusive fitness theory posits that altruistic behaviors, which are directed more likely towards relatives, should be favored by natural selection. However, the prevalence of alternative parenting behaviors in offspring selection, including rejecting their own offspring and accepting the offspring of others, remains poorly understood within the context of parental care evolution. In order to investigate the factors that prompt the occurrence of alternative parenting behaviors, we designed a series of experiments in the Azure-winged Magpie (<em>Cyanopica cyanus</em>). By manipulating the nest spatial position or offspring age/number and parent-offspring familiarity, we addressed how parents provided parental care for the manipulated offspring. In the nest resettlement experiment, the probability of parents rejecting their own offspring significantly increased with nest-moving distances while decreased with offspring ages. In the cross-fostering experiments, the probability of parents provisioning unrelated young significantly decreased with the age difference between cross-fostered chicks. In the nest duplication experiments, where parents were given a choice between familiar offspring and unfamiliar unrelated chicks or between unfamiliar offspring and familiar unrelated chicks, the probability of both alternative parenting behaviors was significantly influenced by the time when parental association with their offspring was deprived. We conclude that as offspring phenotypic traits become individualized and fixed at a special developmental stage, parents gradually acquire the capacity for offspring recognition by associating with them. Any factors that disrupt parent–offspring association or introduce unrelated young into the nest prior to this critical timeline can result in the occurrence of alternative parenting behaviors.</div></div>","PeriodicalId":51311,"journal":{"name":"Avian Research","volume":"16 1","pages":"Article 100218"},"PeriodicalIF":1.6,"publicationDate":"2024-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143099474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Nestlings of two parrotbill species can independently evaluate the presence of predators based on acoustic cues

IF 1.6 2区生物学 Q1 ORNITHOLOGY

Avian Research

Pub Date : 2024-11-27 DOI: 10.1016/j.avrs.2024.100217

Jiaojiao Wang , Peng Pan , Haijie Zhang , Laikun Ma , Qindong Zhou , Longwu Wang , Jianhua Hou

Nest predation is the leading cause of reproductive failure in birds and a major driving force in the evolution of anti-predation strategies. Current studies on the anti-predation strategies of birds driven by predation pressure have mainly focused on adults. However, the detection and behavioral responses of nestlings toward predation risk require further investigation. In this study, we examined nestling responses to predator sounds. Two species of nestlings, the Reed Parrotbill (Paradoxornis heudei) and Vinous-throated Parrotbill (Sinosuthora webbiana), were exposed to the Sparrowhawk (Accipiter nisus, less common) and Oriental Magpie (Pica serica, more common), which are predator species, the Oriental Turtle Dove (Streptopelia orientalis), which is a commonly found harmless species, and background noise. Our findings revealed that compared to pre-playback of natural begging and playback of background noise and Oriental Turtle Dove sounds, playback of the two predator types decreased the total begging time and total number of calls of the two nestlings species, with the calls of the Sparrowhawk leading to greater suppression of nestling begging behavior than those of the Oriental Magpie. Therefore, our results indicated that these nestlings were able to distinguish predators from harmless species based on auditory cues.

{"title":"Nestlings of two parrotbill species can independently evaluate the presence of predators based on acoustic cues","authors":"Jiaojiao Wang , Peng Pan , Haijie Zhang , Laikun Ma , Qindong Zhou , Longwu Wang , Jianhua Hou","doi":"10.1016/j.avrs.2024.100217","DOIUrl":"10.1016/j.avrs.2024.100217","url":null,"abstract":"<div><div>Nest predation is the leading cause of reproductive failure in birds and a major driving force in the evolution of anti-predation strategies. Current studies on the anti-predation strategies of birds driven by predation pressure have mainly focused on adults. However, the detection and behavioral responses of nestlings toward predation risk require further investigation. In this study, we examined nestling responses to predator sounds. Two species of nestlings, the Reed Parrotbill (<em>Paradoxornis heudei</em>) and Vinous-throated Parrotbill (<em>Sinosuthora webbiana</em>), were exposed to the Sparrowhawk (<em>Accipiter nisus</em>, less common) and Oriental Magpie (<em>Pica serica</em>, more common), which are predator species, the Oriental Turtle Dove (<em>Streptopelia orientalis</em>), which is a commonly found harmless species, and background noise. Our findings revealed that compared to pre-playback of natural begging and playback of background noise and Oriental Turtle Dove sounds, playback of the two predator types decreased the total begging time and total number of calls of the two nestlings species, with the calls of the Sparrowhawk leading to greater suppression of nestling begging behavior than those of the Oriental Magpie. Therefore, our results indicated that these nestlings were able to distinguish predators from harmless species based on auditory cues.</div></div>","PeriodicalId":51311,"journal":{"name":"Avian Research","volume":"16 1","pages":"Article 100217"},"PeriodicalIF":1.6,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143099473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0