Michael C. Thompson, Mark J. Ducey, John S. Gunn, Rebecca J. Rowe
Passively collected acoustic data have become increasingly common in wildlife research and have prompted the development of machine‐learning approaches to extract and classify large sets of audio files. BirdNET is an open‐source automatic prediction model that is popular because of its lack of training requirements for end users. Several studies have sought to test the accuracy of BirdNET and illustrate its potential in occupancy modelling of single or multiple species. However, these techniques either require extensive statistical knowledge or computational power to be applied to large datasets. In addition, there is a lack of comparisons of occupancy and community composition calculated using BirdNET and typical field methods. Here we develop a framework for assessing the accuracy of BirdNET using generalized linear mixed models to determine species‐specific confidence score thresholds. We then compare community composition under our model and another post‐processing approach to field data collected from co‐located point count surveys in northeastern Vermont. Our framework outperformed the other post‐processing method and resulted in species composition similar to that of point count surveys. Our work highlights the potential mismatch between accuracy and confidence score and the importance of developing species‐specific thresholds. The framework can facilitate research on large acoustic datasets and can be applied to output from BirdNET or other automatic prediction models.
{"title":"A post‐processing framework for assessing BirdNET identification accuracy and community composition","authors":"Michael C. Thompson, Mark J. Ducey, John S. Gunn, Rebecca J. Rowe","doi":"10.1111/ibi.13357","DOIUrl":"https://doi.org/10.1111/ibi.13357","url":null,"abstract":"Passively collected acoustic data have become increasingly common in wildlife research and have prompted the development of machine‐learning approaches to extract and classify large sets of audio files. BirdNET is an open‐source automatic prediction model that is popular because of its lack of training requirements for end users. Several studies have sought to test the accuracy of BirdNET and illustrate its potential in occupancy modelling of single or multiple species. However, these techniques either require extensive statistical knowledge or computational power to be applied to large datasets. In addition, there is a lack of comparisons of occupancy and community composition calculated using BirdNET and typical field methods. Here we develop a framework for assessing the accuracy of BirdNET using generalized linear mixed models to determine species‐specific confidence score thresholds. We then compare community composition under our model and another post‐processing approach to field data collected from co‐located point count surveys in northeastern Vermont. Our framework outperformed the other post‐processing method and resulted in species composition similar to that of point count surveys. Our work highlights the potential mismatch between accuracy and confidence score and the importance of developing species‐specific thresholds. The framework can facilitate research on large acoustic datasets and can be applied to output from BirdNET or other automatic prediction models.","PeriodicalId":13254,"journal":{"name":"Ibis","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142258141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jarrett, D., Lehikoinen, A. & Willis, S. 2024. Monitoring wader breeding productivity. Ibis166: 780–800.
The following changes were made to the above published article.
The name of the third author should be “Stephen G. Willis”, not “Steve Willis”.
The name of the host institute for Jarrett and Willis should have been the ‘Department of Biosciences’ and not the ‘School of Biological and Biomedical Sciences’.
Finally, the acknowledgements section should have stated that “This work was funded by Leverhulme Trust Doctoral Studentship Grant DS-2017-070 (Interdisciplinary Understanding for a Changing Arctic)”.
The original published article has been updated to reflect these changes.
We apologize for this error.
Jarrett, D., Lehikoinen, A. & Willis, S. 2024.监测涉禽繁殖生产力。Ibis 166：780-800.The following changes were made to the above published article.The name of the third author should be "Stephen G. Willis", not "Steve Willis".The host institute of Jarrett and Willis should have been the 'Department of Biosciences' and not the 'School of Biological and Biomedical Sciences'.最后，致谢部分应该写明："本研究工作得到了 Leverhulme Trust 博士生资助金 DS-2017-070 （跨学科理解不断变化的北极）的资助"。
{"title":"Correction to “Monitoring wader breeding productivity”","authors":"","doi":"10.1111/ibi.13355","DOIUrl":"10.1111/ibi.13355","url":null,"abstract":"<p>Jarrett, D., Lehikoinen, A. & Willis, S. 2024. Monitoring wader breeding productivity. <i>Ibis</i> <b>166</b>: 780–800.</p><p>The following changes were made to the above published article.</p><p>The name of the third author should be “Stephen G. Willis”, not “Steve Willis”.</p><p>The name of the host institute for Jarrett and Willis should have been the ‘Department of Biosciences’ and not the ‘School of Biological and Biomedical Sciences’.</p><p>Finally, the acknowledgements section should have stated that “This work was funded by Leverhulme Trust Doctoral Studentship Grant DS-2017-070 (Interdisciplinary Understanding for a Changing Arctic)”.</p><p>The original published article has been updated to reflect these changes.</p><p>We apologize for this error.</p>","PeriodicalId":13254,"journal":{"name":"Ibis","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/ibi.13355","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142225571","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Recently, there has been increased focus on the origins and history of common names for organisms, especially birds. Of particular interest are eponymous common names that reflect our colonial past. While identification of alternative names can be straightforward for some species, for those that migrate across jurisdictions including the lands of multiple Traditional Owner/Indigenous groups, reaching consensus on a single name that reflects the features of the species and their cultural importance can be substantially more complex. Using the migratory Ardenna carneipes as a case study, we propose a new common name (Sable Shearwater) for the species and discuss the many challenges that others will need to consider when navigating this important yet sensitive space.
{"title":"A feathered past: Colonial influences on bird naming practices, and a new common name for Ardenna carneipes (Gould 1844)","authors":"Alexander L. Bond, Jennifer L. Lavers","doi":"10.1111/ibi.13356","DOIUrl":"10.1111/ibi.13356","url":null,"abstract":"<p>Recently, there has been increased focus on the origins and history of common names for organisms, especially birds. Of particular interest are eponymous common names that reflect our colonial past. While identification of alternative names can be straightforward for some species, for those that migrate across jurisdictions including the lands of multiple Traditional Owner/Indigenous groups, reaching consensus on a single name that reflects the features of the species and their cultural importance can be substantially more complex. Using the migratory <i>Ardenna carneipes</i> as a case study, we propose a new common name (Sable Shearwater) for the species and discuss the many challenges that others will need to consider when navigating this important yet sensitive space.</p>","PeriodicalId":13254,"journal":{"name":"Ibis","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/ibi.13356","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142225568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Antonio Hernández‐Matías, Iván Peragón, Jaime Resano‐Mayor, Marcos Moleón, Emilio Virgós, Joan Real
The recognition of individual variation has fundamental implications for ecological, evolutionary and biodiversity conservation. There is increasing theoretical interest in how spatial and temporal variation in the environment can create differences in the demographic contribution of individuals over space and time. However, empirical information about the characteristics of the environmental drivers of key vital rates and their spatiotemporal variation is still scarce. Here, we used data generated by a monitoring scheme (1990–2015) of a population of a long‐lived territorial avian predator, Bonelli's Eagle Aquila fasciata, which included estimations of individuals' diet through stable isotope analysis (2008–15), to evaluate whether temporal consistency in spatially structured dietary patterns affects key demographic parameters, namely productivity and survival, at territory scales. We found strong within‐population heterogeneity in survival and reproduction rates associated with Eagle territories, with territory average values ranging, respectively, from 0.58 to 1.00 and from 0 to 1.71 for the overall study period. Reproduction and survival were predictable over, respectively, 4‐ and 3‐year periods for the bulk of the population, which suggests that the environmental drivers of these vital rates changed at these temporal scales. Interestingly, the characteristics of and the temporal variation in the diets of territorial individuals during these periods were associated with their survival and reproduction. Based on these findings, we suggest that spatial and temporal variations in trophic scenarios potentially act as meaningful drivers of intrapopulation demographic heterogeneity.
{"title":"Temporal and spatial variation in trophic scenarios affects population demographic heterogeneity in Bonelli's Eagle (Aquila fasciata)","authors":"Antonio Hernández‐Matías, Iván Peragón, Jaime Resano‐Mayor, Marcos Moleón, Emilio Virgós, Joan Real","doi":"10.1111/ibi.13351","DOIUrl":"https://doi.org/10.1111/ibi.13351","url":null,"abstract":"The recognition of individual variation has fundamental implications for ecological, evolutionary and biodiversity conservation. There is increasing theoretical interest in how spatial and temporal variation in the environment can create differences in the demographic contribution of individuals over space and time. However, empirical information about the characteristics of the environmental drivers of key vital rates and their spatiotemporal variation is still scarce. Here, we used data generated by a monitoring scheme (1990–2015) of a population of a long‐lived territorial avian predator, Bonelli's Eagle <jats:italic>Aquila fasciata</jats:italic>, which included estimations of individuals' diet through stable isotope analysis (2008–15), to evaluate whether temporal consistency in spatially structured dietary patterns affects key demographic parameters, namely productivity and survival, at territory scales. We found strong within‐population heterogeneity in survival and reproduction rates associated with Eagle territories, with territory average values ranging, respectively, from 0.58 to 1.00 and from 0 to 1.71 for the overall study period. Reproduction and survival were predictable over, respectively, 4‐ and 3‐year periods for the bulk of the population, which suggests that the environmental drivers of these vital rates changed at these temporal scales. Interestingly, the characteristics of and the temporal variation in the diets of territorial individuals during these periods were associated with their survival and reproduction. Based on these findings, we suggest that spatial and temporal variations in trophic scenarios potentially act as meaningful drivers of intrapopulation demographic heterogeneity.","PeriodicalId":13254,"journal":{"name":"Ibis","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142225569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Iván Alambiaga, Pablo Vera, David García, Maties Rebassa, Juan S. Monrós
Wetland degradation worldwide has led to fragmentation and isolation of diminished populations that are now more vulnerable to disturbance. Wildfires affecting wetlands can have major impacts on vegetation structure and associated waterbird communities, but rapid recovery of the initial state of vegetation cover after fire due to fast emergent vegetation dynamism has turned prescribed fire into a recurrent management method in these systems. S'Albufera de Mallorca Natural Park (Balearic Islands, Spain) was affected in 2020 by a wildfire that impacted 25% of the wetland area, including territories of Eastern Iberian Reed Bunting Emberiza schoeniclus witherbyi, a nationally critically endangered subspecies. In this study we analysed potential effects of wildfire on the breeding population of this subspecies to determine how active fire management could contribute to its conservation. Specifically, we tested whether there were structural variations in marsh vegetation as well as changes in Eastern Iberian Reed Bunting territory distribution and spatial ecology of breeding males 3 years after the fire. There were no differences in vegetation structure between affected and unaffected areas, but there was an increased density of breeding territories and higher male home‐range overlap in affected areas after burning. Home‐range size was not influenced by fire but by habitat, with males established in saw sedges having larger home‐ranges than those in reed beds, probably due to greater movements in safer saw sedge nesting habitats with lower food availability. Prescribed fire may be a useful and cost‐effective conservation tool for Eastern Iberian Reed Bunting populations by creating heterogeneous areas of mixed reed and saw sedge as suitable habitat patches for this subspecies.
{"title":"Conservation and management implications of the effects of wildfire on a threatened Eastern Iberian Reed Bunting (Emberiza schoeniclus witherbyi) population","authors":"Iván Alambiaga, Pablo Vera, David García, Maties Rebassa, Juan S. Monrós","doi":"10.1111/ibi.13352","DOIUrl":"https://doi.org/10.1111/ibi.13352","url":null,"abstract":"Wetland degradation worldwide has led to fragmentation and isolation of diminished populations that are now more vulnerable to disturbance. Wildfires affecting wetlands can have major impacts on vegetation structure and associated waterbird communities, but rapid recovery of the initial state of vegetation cover after fire due to fast emergent vegetation dynamism has turned prescribed fire into a recurrent management method in these systems. S'Albufera de Mallorca Natural Park (Balearic Islands, Spain) was affected in 2020 by a wildfire that impacted 25% of the wetland area, including territories of Eastern Iberian Reed Bunting <jats:italic>Emberiza schoeniclus witherbyi</jats:italic>, a nationally critically endangered subspecies. In this study we analysed potential effects of wildfire on the breeding population of this subspecies to determine how active fire management could contribute to its conservation. Specifically, we tested whether there were structural variations in marsh vegetation as well as changes in Eastern Iberian Reed Bunting territory distribution and spatial ecology of breeding males 3 years after the fire. There were no differences in vegetation structure between affected and unaffected areas, but there was an increased density of breeding territories and higher male home‐range overlap in affected areas after burning. Home‐range size was not influenced by fire but by habitat, with males established in saw sedges having larger home‐ranges than those in reed beds, probably due to greater movements in safer saw sedge nesting habitats with lower food availability. Prescribed fire may be a useful and cost‐effective conservation tool for Eastern Iberian Reed Bunting populations by creating heterogeneous areas of mixed reed and saw sedge as suitable habitat patches for this subspecies.","PeriodicalId":13254,"journal":{"name":"Ibis","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142225570","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Fuertes-Recuero, Davide Baldan, Alejandro Cantarero
Hatching failure, due to infertility or embryo mortality, is an important factor contributing to reduced reproductive success in birds. Although hatching failure and its possible causes have been widely investigated, the stage of development at which embryo death occurs and its association with laying order have rarely been studied. The relative size of eggs laid in different positions within the laying order is a key factor that can lead to different parental reproductive strategies, such as hatching asynchrony. Here we investigate hatching failure in relation to laying order by establishing the developmental stage of dead embryos found in unhatched European Pied Flycatcher Ficedula hypoleuca eggs and considering possible causes of failure. We found that variation in egg dimensions showed a quadratic relationship with laying order, with relatively large volumes and sizes in the first and last positions of the clutch. Egg position in the laying sequence was also related to hatching failure, with the first and last positions being more susceptible to failure. The death of embryos late in development was more likely for eggs laid later in the sequence. To our knowledge, this is the first study showing that females may be adaptively allocating more resources to last‐laid eggs to avoid competitive disadvantages between siblings, a strategy that seems to fail becasue these eggs suffer greater embryo mortality.
{"title":"Hatching asynchrony as a reproductive strategy in birds may explain the hatching failure of the last eggs of the clutch","authors":"M. Fuertes-Recuero, Davide Baldan, Alejandro Cantarero","doi":"10.1111/ibi.13354","DOIUrl":"https://doi.org/10.1111/ibi.13354","url":null,"abstract":"Hatching failure, due to infertility or embryo mortality, is an important factor contributing to reduced reproductive success in birds. Although hatching failure and its possible causes have been widely investigated, the stage of development at which embryo death occurs and its association with laying order have rarely been studied. The relative size of eggs laid in different positions within the laying order is a key factor that can lead to different parental reproductive strategies, such as hatching asynchrony. Here we investigate hatching failure in relation to laying order by establishing the developmental stage of dead embryos found in unhatched European Pied Flycatcher Ficedula hypoleuca eggs and considering possible causes of failure. We found that variation in egg dimensions showed a quadratic relationship with laying order, with relatively large volumes and sizes in the first and last positions of the clutch. Egg position in the laying sequence was also related to hatching failure, with the first and last positions being more susceptible to failure. The death of embryos late in development was more likely for eggs laid later in the sequence. To our knowledge, this is the first study showing that females may be adaptively allocating more resources to last‐laid eggs to avoid competitive disadvantages between siblings, a strategy that seems to fail becasue these eggs suffer greater embryo mortality.","PeriodicalId":13254,"journal":{"name":"Ibis","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141920239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ana P. Coelho, Afonso D. Rocha, A. R. de Barros, T. Piersma, José A. Alves
Shorebirds migrating along the East Atlantic Flyway must travel long distances from their breeding sites in arctic and subarctic regions to wintering areas in Europe and Africa. Selecting a winter location is an important decision, as it can have both immediate and future consequences. Shorebirds must ensure they have enough resources to fulfil their energetic requirements during winter, as well as during the fuelling phase, when they must accumulate fat stores for the return migration. Migratory shorebirds are declining worldwide, with several populations wintering in tropical Africa facing steep declines, particularly when compared with their conspecifics wintering in temperate Europe. However, one of the most important wintering sites in Africa remains relatively unstudied, the Bijagós Archipelago, Guinea‐Bissau. In this study, we quantify intake rates of eight migratory shorebird species wintering in the Bijagós and explore how these vary throughout their stay in the archipelago. Given the uncertainties associated with measurements of field intake rates, an allometric validation of our approach confirmed a slope comparable to that predicted by theory and verified in many situations. Contrary to our expectations, we found no evidence for an increase in intake rates in the fuelling period; in fact, decreases were noticeable in a few species over the non‐breeding season. The allometric relationship across species also confirmed the seasonally decreasing daily energetic intakes, particularly by smaller species. The comparison between the intake rates in the Bijagós and those reported in other wintering sites along the flyway highlights the particularly low values for Ringed Plover Charadrius hiaticula, Curlew Sandpiper Calidris ferruginea and Bar‐tailed Godwit Limosa lapponica. Limitations in intake rates and the associated energetic intake suggest that some species may be energetically constrained in the Bijagós, particularly during fuelling.
{"title":"An allometric approach to seasonal changes in intake rates of migratory shorebirds in the Bijagós Archipelago, Guinea‐Bissau","authors":"Ana P. Coelho, Afonso D. Rocha, A. R. de Barros, T. Piersma, José A. Alves","doi":"10.1111/ibi.13348","DOIUrl":"https://doi.org/10.1111/ibi.13348","url":null,"abstract":"Shorebirds migrating along the East Atlantic Flyway must travel long distances from their breeding sites in arctic and subarctic regions to wintering areas in Europe and Africa. Selecting a winter location is an important decision, as it can have both immediate and future consequences. Shorebirds must ensure they have enough resources to fulfil their energetic requirements during winter, as well as during the fuelling phase, when they must accumulate fat stores for the return migration. Migratory shorebirds are declining worldwide, with several populations wintering in tropical Africa facing steep declines, particularly when compared with their conspecifics wintering in temperate Europe. However, one of the most important wintering sites in Africa remains relatively unstudied, the Bijagós Archipelago, Guinea‐Bissau. In this study, we quantify intake rates of eight migratory shorebird species wintering in the Bijagós and explore how these vary throughout their stay in the archipelago. Given the uncertainties associated with measurements of field intake rates, an allometric validation of our approach confirmed a slope comparable to that predicted by theory and verified in many situations. Contrary to our expectations, we found no evidence for an increase in intake rates in the fuelling period; in fact, decreases were noticeable in a few species over the non‐breeding season. The allometric relationship across species also confirmed the seasonally decreasing daily energetic intakes, particularly by smaller species. The comparison between the intake rates in the Bijagós and those reported in other wintering sites along the flyway highlights the particularly low values for Ringed Plover Charadrius hiaticula, Curlew Sandpiper Calidris ferruginea and Bar‐tailed Godwit Limosa lapponica. Limitations in intake rates and the associated energetic intake suggest that some species may be energetically constrained in the Bijagós, particularly during fuelling.","PeriodicalId":13254,"journal":{"name":"Ibis","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141924161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Coastal developments are ever‐expanding and increasing the use of artificial lights within marine environments. Yet there is conflicting research on the impact of artificial lights on seabirds. Here, we experimentally investigated the impacts of artificial white lights on the behaviours (arrival time, group size, number of groups and vigilance) of breeding Little Penguins Eudyptula minor. Little Penguins are central‐place foragers that spend daylight hours foraging at sea and return to their breeding colony after sunset to attend to their chicks or relieve their incubating partners. We exposed Little Penguins returning to their colony at night to either (1) a self‐sustaining white LED floodlight or (2) a control system with a decoy light turned ‘off’. We used two different landing sites (site 1, site 2) that differed in landscape characteristics to assess whether behavioural responses to light were site‐specific. Little Penguins arrived in larger groups at the landing site 2. Regardless of site, we observed fewer groups that arrived earlier when the light was ‘on’. The effects of artificial light (or ‘lack of artificial light’) on the vigilance of Little Penguins were site‐specific, with Little Penguins spending proportionally more time in vigilance when the light was ‘off’ at site 2 compared with site 1. Our results support the idea that artificial lights produced from coastal developments can alter penguin behaviours, but that the effects of artificial lights can be context‐dependent and need to be assessed on a case‐by‐case basis.
{"title":"Bright and early: artificial light affects arrival time, but not group size or vigilance in Little Penguins (Eudyptula minor)","authors":"Larissa Iasiello, Diane Colombelli‐Négrel","doi":"10.1111/ibi.13349","DOIUrl":"https://doi.org/10.1111/ibi.13349","url":null,"abstract":"Coastal developments are ever‐expanding and increasing the use of artificial lights within marine environments. Yet there is conflicting research on the impact of artificial lights on seabirds. Here, we experimentally investigated the impacts of artificial white lights on the behaviours (arrival time, group size, number of groups and vigilance) of breeding Little Penguins <jats:italic>Eudyptula minor</jats:italic>. Little Penguins are central‐place foragers that spend daylight hours foraging at sea and return to their breeding colony after sunset to attend to their chicks or relieve their incubating partners. We exposed Little Penguins returning to their colony at night to either (1) a self‐sustaining white LED floodlight or (2) a control system with a decoy light turned ‘off’. We used two different landing sites (site 1, site 2) that differed in landscape characteristics to assess whether behavioural responses to light were site‐specific. Little Penguins arrived in larger groups at the landing site 2. Regardless of site, we observed fewer groups that arrived earlier when the light was ‘on’. The effects of artificial light (or ‘lack of artificial light’) on the vigilance of Little Penguins were site‐specific, with Little Penguins spending proportionally more time in vigilance when the light was ‘off’ at site 2 compared with site 1. Our results support the idea that artificial lights produced from coastal developments can alter penguin behaviours, but that the effects of artificial lights can be context‐dependent and need to be assessed on a case‐by‐case basis.","PeriodicalId":13254,"journal":{"name":"Ibis","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141945432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Katharina Reusch, Maëlle Connan, Peter G. Ryan, Mike Butler, Lorien Pichegru
Opportunistic species, including some gulls (Laridae), can benefit from urbanization and increased anthropogenic food resources. Knowledge of the level of exploitation of anthropogenic resources by gulls is crucial to understand how changes in food availability might affect their populations, which in turn may impact other species. The Kelp Gull Larus dominicanus is widely distributed in the southern hemisphere and consumes a wide variety of resources, from waste in landfills to seabirds. We assessed if proximity to landfills influenced the diet and trophic ecology of Kelp Gull incubating adults and chicks using a combination of conventional diet sampling (stomach contents, regurgitated pellets), and carbon and nitrogen stable isotope analysis of blood plasma in seven colonies over two consecutive years in South Africa. Kelp Gulls consumed a variety of resources, including marine (e.g. fish), coastal (e.g. molluscs), terrestrial natural (e.g. insects, mammals), or terrestrial anthropogenic (e.g. chicken, bread) items. Inter‐annual differences were most apparent among gulls breeding next to a seabird colony, whereas gulls breeding at other colonies were more consistent in diet and trophic ecology. At most colonies, chicks were fed more natural and higher trophic level food items than were consumed by incubating adults. Overall, distance to landfill did not strongly affect the diet and trophic ecology and our results suggest that the Kelp Gull's broad feeding ecology allows it to buffer changes in food availability by switching among food resources. However, such dietary changes triggered by human actions may impact other species, including threatened seabirds.
{"title":"Spatio‐temporal differences in the diet and trophic ecology of Kelp Gulls (Larus dominicanus) in South Africa","authors":"Katharina Reusch, Maëlle Connan, Peter G. Ryan, Mike Butler, Lorien Pichegru","doi":"10.1111/ibi.13344","DOIUrl":"https://doi.org/10.1111/ibi.13344","url":null,"abstract":"Opportunistic species, including some gulls (Laridae), can benefit from urbanization and increased anthropogenic food resources. Knowledge of the level of exploitation of anthropogenic resources by gulls is crucial to understand how changes in food availability might affect their populations, which in turn may impact other species. The Kelp Gull <jats:italic>Larus dominicanus</jats:italic> is widely distributed in the southern hemisphere and consumes a wide variety of resources, from waste in landfills to seabirds. We assessed if proximity to landfills influenced the diet and trophic ecology of Kelp Gull incubating adults and chicks using a combination of conventional diet sampling (stomach contents, regurgitated pellets), and carbon and nitrogen stable isotope analysis of blood plasma in seven colonies over two consecutive years in South Africa. Kelp Gulls consumed a variety of resources, including marine (e.g. fish), coastal (e.g. molluscs), terrestrial natural (e.g. insects, mammals), or terrestrial anthropogenic (e.g. chicken, bread) items. Inter‐annual differences were most apparent among gulls breeding next to a seabird colony, whereas gulls breeding at other colonies were more consistent in diet and trophic ecology. At most colonies, chicks were fed more natural and higher trophic level food items than were consumed by incubating adults. Overall, distance to landfill did not strongly affect the diet and trophic ecology and our results suggest that the Kelp Gull's broad feeding ecology allows it to buffer changes in food availability by switching among food resources. However, such dietary changes triggered by human actions may impact other species, including threatened seabirds.","PeriodicalId":13254,"journal":{"name":"Ibis","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141871843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lorenzo Serra, Matteo Griggio, Giulia Casasole, Simone Pirrello, Leonida Fusani, Andrea Pilastro
Feather colours can be produced by the organization of feather microstructure, by pigmentation (mainly due to melanins and carotenoids) or both. The expression of feather colours is usually influenced by testosterone (T) levels through several interacting mechanisms. First, high T levels can negatively affect bird condition and hence the expression of condition‐dependent feather colours (e.g. carotenoid‐based colours). Secondly, high levels of T can slow moult progression, which in turn may result in brighter colours, as moult speed has been shown to be negatively correlated with the expression of feather colours. Thirdly, T can affect the bioavailability of pigments that are involved in feather colours. The effect of experimental manipulation of T levels may therefore influence, either positively or negatively, feather colour expression according to the relative importance of these mechanisms and the type of coloration involved. We experimentally investigated whether plumage coloration is affected by T in yearling Eurasian Blue Tits Cyanistes caeruleus. We implanted 11 males and 11 females with T (T‐birds) at the onset of their post‐juvenile moult and compared the spectral reflectance of their structural ultraviolet (UV)/blue colour (crown feathers and upper lesser wing‐coverts) and carotenoid‐based yellow colour (breast feathers) with those of control birds (C‐birds) that were sham‐implanted (12 males, 16 females). At the implant date, all the right lesser wing‐coverts were plucked in both experimental groups to test the effect of T on feathers grown exclusively during our treatment. After 40 days, the implants were removed. Two weeks before removing the implants, the mean T plasma levels were assayed (average 3.21 ng/mL in T‐birds and 0.33 ng/mL in C‐birds). In T‐birds, body moult progression was suspended, and moult was resumed 33 days after implant removal. Moult duration from implant date, excluding suspension, did not differ between treatments and controls. T had a negative effect on UV coloration only in plumage that started growing exclusively during the treatment (right lesser wing‐coverts), and not in other UV/blue plumage. In contrast, the carotenoid‐based yellow coloration of the breast increased in T‐birds, suggesting an immediate effect of T on the mobilization of carotenoids available for ornamentation. Despite sexual dichromatism, T treatment had similar effects in the two sexes. Our results highlight the importance of considering the effect of T on moult speed and possibly moult suspension in the interpretation of the results of studies based on T manipulation.
羽毛颜色可以通过羽毛微观结构的组织、色素沉积（主要是黑色素和类胡萝卜素）或两者共同作用产生。羽毛颜色的表现通常会受到睾酮（T）水平的影响，这种影响会通过几种相互作用的机制产生。首先，高水平的睾酮会对鸟类的状态产生负面影响，从而影响与状态相关的羽毛颜色（如类胡萝卜素颜色）的表现。其次，高水平的睾丸激素可减缓蜕皮速度，进而使羽毛颜色更鲜艳，因为蜕皮速度与羽毛颜色的表现呈负相关。第三，T 会影响与羽毛颜色有关的色素的生物利用率。因此，根据这些机制的相对重要性和所涉及的着色类型，实验操作 T 水平的效果可能会对羽毛颜色的表达产生积极或消极的影响。我们通过实验研究了一岁的欧亚蓝山雀（Cyanistes caeruleus）的羽毛颜色是否受 T 的影响。我们在 11 只雄鸟和 11 只雌鸟幼鸟蜕皮初期植入了 T（T-鸟），并将其结构性紫外线（UV）/蓝色（冠羽和上小翼盖）和类胡萝卜素黄色（胸羽）的光谱反射率与假植入的对照鸟（C-鸟）（12 只雄鸟，16 只雌鸟）进行了比较。在植入日，拔掉两组实验组的所有右侧小翼盖，以测试 T 对治疗期间生长的羽毛的影响。40 天后，取出植入物。移除植入物前两周，检测血浆中 T 的平均水平（T 组鸟类平均为 3.21 纳克/毫升，C 组鸟类平均为 0.33 纳克/毫升）。T 型鸟的蜕皮过程被中止，在植入物移除 33 天后恢复蜕皮。从植入之日起（不包括暂停）的蜕皮持续时间在处理和对照之间没有差异。类胡萝卜素只对处理期间开始生长的羽毛（右侧小翼盖）的紫外线颜色有负面影响，而对其他紫外线/蓝色羽毛没有影响。与此相反，T 型鸟胸部的类胡萝卜素黄色增加，这表明 T 型对可用于装饰的类胡萝卜素的调动有直接影响。尽管存在性二色性，但T处理对雌雄鸟的影响相似。我们的研究结果突出表明，在解释基于T操纵的研究结果时，考虑T对蜕皮速度的影响以及可能对蜕皮暂停的影响非常重要。
{"title":"Elevated testosterone levels during moult have contrasting effects on structural and carotenoid‐based plumage colours in Eurasian Blue Tits","authors":"Lorenzo Serra, Matteo Griggio, Giulia Casasole, Simone Pirrello, Leonida Fusani, Andrea Pilastro","doi":"10.1111/ibi.13347","DOIUrl":"https://doi.org/10.1111/ibi.13347","url":null,"abstract":"Feather colours can be produced by the organization of feather microstructure, by pigmentation (mainly due to melanins and carotenoids) or both. The expression of feather colours is usually influenced by testosterone (T) levels through several interacting mechanisms. First, high T levels can negatively affect bird condition and hence the expression of condition‐dependent feather colours (e.g. carotenoid‐based colours). Secondly, high levels of T can slow moult progression, which in turn may result in brighter colours, as moult speed has been shown to be negatively correlated with the expression of feather colours. Thirdly, T can affect the bioavailability of pigments that are involved in feather colours. The effect of experimental manipulation of T levels may therefore influence, either positively or negatively, feather colour expression according to the relative importance of these mechanisms and the type of coloration involved. We experimentally investigated whether plumage coloration is affected by T in yearling Eurasian Blue Tits <jats:italic>Cyanistes caeruleus.</jats:italic> We implanted 11 males and 11 females with T (T‐birds) at the onset of their post‐juvenile moult and compared the spectral reflectance of their structural ultraviolet (UV)/blue colour (crown feathers and upper lesser wing‐coverts) and carotenoid‐based yellow colour (breast feathers) with those of control birds (C‐birds) that were sham‐implanted (12 males, 16 females). At the implant date, all the right lesser wing‐coverts were plucked in both experimental groups to test the effect of T on feathers grown exclusively during our treatment. After 40 days, the implants were removed. Two weeks before removing the implants, the mean T plasma levels were assayed (average 3.21 ng/mL in T‐birds and 0.33 ng/mL in C‐birds). In T‐birds, body moult progression was suspended, and moult was resumed 33 days after implant removal. Moult duration from implant date, excluding suspension, did not differ between treatments and controls. T had a negative effect on UV coloration only in plumage that started growing exclusively during the treatment (right lesser wing‐coverts), and not in other UV/blue plumage. In contrast, the carotenoid‐based yellow coloration of the breast increased in T‐birds, suggesting an immediate effect of T on the mobilization of carotenoids available for ornamentation. Despite sexual dichromatism, T treatment had similar effects in the two sexes. Our results highlight the importance of considering the effect of T on moult speed and possibly moult suspension in the interpretation of the results of studies based on T manipulation.","PeriodicalId":13254,"journal":{"name":"Ibis","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141871842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：