Pub Date : 2022-04-03DOI: 10.1080/00063657.2022.2139814
H. Hanmer, D. Dadam, G. Siriwardena
ABSTRACT Capsule: Blue Tits Cyanistes caeruleus and Great Tits Parus major wintering in rural areas tended to move further to breed the following breeding season and more frequently cross the urban–rural boundary, than did those wintering in urban gardens. Aims: To explore and quantify the movements of birds from winter to breeding season locations across the urban–rural ecotone at the boundary of a large urban area. Methods: Birds were colour-ringed at rural and urban/suburban garden ringing sites during the winter. This was followed by breeding season surveys and resighting in the surrounding areas to quantify the movements of colour-ringed birds and changes in habitat selection between seasons. Results: Blue Tits and Great Tits ringed in winter in rural areas tended to move further and selected more urbanized breeding territories the following spring than did urban/suburban garden-ringed conspecifics. This shows that the populations were connected across the urban–rural ecotone by the seasonal movements of individuals, but that net movement was from rural wintering areas to urban breeding habitat. Conclusion: The results suggest that rural populations may not be subsidized by urban wintering birds and winter supplementary feeding, but that the resources in gardens within urban areas, perhaps spring/summer feeding and nestboxes, draw birds in to breed. Combined with independent evidence for lower breeding success in urban areas, this may show the operation of source-sink dynamics. The results suggest important implications for connections between populations, the conservation value of urban areas and potential for the spread of disease, but further work is required to extend evidence and inference to other regions and species. Nevertheless, the approach used here provides a scalable study model that can be applied in other contexts.
{"title":"Evidence that rural wintering bird populations supplement suburban breeding populations","authors":"H. Hanmer, D. Dadam, G. Siriwardena","doi":"10.1080/00063657.2022.2139814","DOIUrl":"https://doi.org/10.1080/00063657.2022.2139814","url":null,"abstract":"ABSTRACT Capsule: Blue Tits Cyanistes caeruleus and Great Tits Parus major wintering in rural areas tended to move further to breed the following breeding season and more frequently cross the urban–rural boundary, than did those wintering in urban gardens. Aims: To explore and quantify the movements of birds from winter to breeding season locations across the urban–rural ecotone at the boundary of a large urban area. Methods: Birds were colour-ringed at rural and urban/suburban garden ringing sites during the winter. This was followed by breeding season surveys and resighting in the surrounding areas to quantify the movements of colour-ringed birds and changes in habitat selection between seasons. Results: Blue Tits and Great Tits ringed in winter in rural areas tended to move further and selected more urbanized breeding territories the following spring than did urban/suburban garden-ringed conspecifics. This shows that the populations were connected across the urban–rural ecotone by the seasonal movements of individuals, but that net movement was from rural wintering areas to urban breeding habitat. Conclusion: The results suggest that rural populations may not be subsidized by urban wintering birds and winter supplementary feeding, but that the resources in gardens within urban areas, perhaps spring/summer feeding and nestboxes, draw birds in to breed. Combined with independent evidence for lower breeding success in urban areas, this may show the operation of source-sink dynamics. The results suggest important implications for connections between populations, the conservation value of urban areas and potential for the spread of disease, but further work is required to extend evidence and inference to other regions and species. Nevertheless, the approach used here provides a scalable study model that can be applied in other contexts.","PeriodicalId":55353,"journal":{"name":"Bird Study","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44081798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-04-03DOI: 10.1080/00063657.2022.2144129
L. Mander, I. Nicholson, R. Green, Steve G. Dodd, R. Forster, N. Burton
ABSTRACT Capsule: Eurasian Curlews Numenius arquata were faithful to foraging and roosting areas on their coastal wintering grounds, including a habitat creation site. Home range sizes were greater at night than during the day, and showed high inter-individual variability which was not related to sex. Aims: To examine factors affecting variation in the winter home range size of the largest European wader species: the near-threatened Eurasian Curlew Numenius arquata. Methods: We examined individual, sexual and temporal (day/night, seasonal and annual) variation in the size of the home ranges of 18 GPS tagged Curlews captured at two sites on the Humber Estuary, UK. Results: Home ranges were small (mean ± SD = 555.5 ± 557.9 ha) and varied slightly in size through the non-breeding season (September–March). We found some annual differences in home range size, and there was some evidence that home range size was greater at night compared to daytime. There was strong inter-individual variation in home range size, which was not related to the species’ sexual size dimorphism and thus potential differences in resource use. Conclusions: Our results highlight that wintering Curlews on the Humber Estuary maintain small home ranges which vary strongly between individuals. Knowledge of the home range size of wintering waders is vital to inform management responses to the potential impacts of environmental changes such as sea-level rise and improving the efficacy of compensatory habitats.
{"title":"Individual, sexual and temporal variation in the winter home range sizes of GPS-tagged Eurasian Curlews Numenius arquata","authors":"L. Mander, I. Nicholson, R. Green, Steve G. Dodd, R. Forster, N. Burton","doi":"10.1080/00063657.2022.2144129","DOIUrl":"https://doi.org/10.1080/00063657.2022.2144129","url":null,"abstract":"ABSTRACT Capsule: Eurasian Curlews Numenius arquata were faithful to foraging and roosting areas on their coastal wintering grounds, including a habitat creation site. Home range sizes were greater at night than during the day, and showed high inter-individual variability which was not related to sex. Aims: To examine factors affecting variation in the winter home range size of the largest European wader species: the near-threatened Eurasian Curlew Numenius arquata. Methods: We examined individual, sexual and temporal (day/night, seasonal and annual) variation in the size of the home ranges of 18 GPS tagged Curlews captured at two sites on the Humber Estuary, UK. Results: Home ranges were small (mean ± SD = 555.5 ± 557.9 ha) and varied slightly in size through the non-breeding season (September–March). We found some annual differences in home range size, and there was some evidence that home range size was greater at night compared to daytime. There was strong inter-individual variation in home range size, which was not related to the species’ sexual size dimorphism and thus potential differences in resource use. Conclusions: Our results highlight that wintering Curlews on the Humber Estuary maintain small home ranges which vary strongly between individuals. Knowledge of the home range size of wintering waders is vital to inform management responses to the potential impacts of environmental changes such as sea-level rise and improving the efficacy of compensatory habitats.","PeriodicalId":55353,"journal":{"name":"Bird Study","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48568178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-04-03DOI: 10.1080/00063657.2022.2138827
R. Fijn, M. Collier
ABSTRACT Flight heights and behaviour of 1460 Sandwich Terns Thalasseus sandvicensis in the Dutch North Sea were recorded with a laser range finder during ship-based surveys in 2020 and 2021. Over 87% of all Sandwich Terns were flying below 20 m, and fewer than 1.5% were recorded above 40 m, leading to a two-fold increase in the collision risk model estimates for the Borssele offshore wind farm in the Netherlands compared to the current standard flight height distributions.
{"title":"Distribution and flight heights of Sandwich Terns Thalasseus sandvicensis during different behaviours near wind farms in the Netherlands","authors":"R. Fijn, M. Collier","doi":"10.1080/00063657.2022.2138827","DOIUrl":"https://doi.org/10.1080/00063657.2022.2138827","url":null,"abstract":"ABSTRACT Flight heights and behaviour of 1460 Sandwich Terns Thalasseus sandvicensis in the Dutch North Sea were recorded with a laser range finder during ship-based surveys in 2020 and 2021. Over 87% of all Sandwich Terns were flying below 20 m, and fewer than 1.5% were recorded above 40 m, leading to a two-fold increase in the collision risk model estimates for the Borssele offshore wind farm in the Netherlands compared to the current standard flight height distributions.","PeriodicalId":55353,"journal":{"name":"Bird Study","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41821420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-02DOI: 10.1080/00063657.2022.2103097
M. Engler, Youri van der Horst, Manuela Merling de Chapa, O. Krone
ABSTRACT Capsule: Compared to their rural counterparts, urban Northern Goshawks Accipiter gentilis potentially maximize their energy delivery to the nest by exploiting heavier prey species close to their maximum carrying capacity. Aims: We aimed to assess prey use of a raptor species with distinct reversed sexual size dimorphism from a perspective of physical limitations during foraging and the transportation of prey. Methods: We estimated the theoretical maximum load carrying capacity (MLCC) of fully developed Northern Goshawks based on their flight muscle mass. Additionally, we collected data on the breeding season diet of Northern Goshawks in urban and rural habitats in Germany. By linking MLCC estimates to the diet we explained the relevance of prey size from a viewpoint of load carrying capacity. Results: Estimates for the mean (± sd) additional portable loads were 684 g (± 237) for males and 971 g (± 235) for females, accounting for 96% and 84% of their body mass, respectively. Overall prey weight averaged higher for urban areas compared to rural ones, while the majority of prey items were between 200 and 500 g and below the estimated MLCC of both sexes, with the exception of single heavy species. Results suggest that prey use of Northern Goshawks during the breeding season is barely limited by prey transportability, since both sexes are physically capable of carrying the majority of prey species to their nest. Conclusions: Urban Northern Goshawks can exploit heavier, available prey species compared to their rural counterparts, allowing them to hunt larger prey closer to their MLCC. Ultimately, by maximizing their energy delivery to the nest, this presumably constitutes one key factor why Goshawks successfully colonized European cities. This study is the first to link estimates of physical limitations in prey transportation for a free-living raptor species to its prey composition in the light of colonizing urban environments.
{"title":"How much to carry? Implications of maximum load carrying capacity for prey use of urban and rural Northern Goshawks Accipiter gentilis","authors":"M. Engler, Youri van der Horst, Manuela Merling de Chapa, O. Krone","doi":"10.1080/00063657.2022.2103097","DOIUrl":"https://doi.org/10.1080/00063657.2022.2103097","url":null,"abstract":"ABSTRACT Capsule: Compared to their rural counterparts, urban Northern Goshawks Accipiter gentilis potentially maximize their energy delivery to the nest by exploiting heavier prey species close to their maximum carrying capacity. Aims: We aimed to assess prey use of a raptor species with distinct reversed sexual size dimorphism from a perspective of physical limitations during foraging and the transportation of prey. Methods: We estimated the theoretical maximum load carrying capacity (MLCC) of fully developed Northern Goshawks based on their flight muscle mass. Additionally, we collected data on the breeding season diet of Northern Goshawks in urban and rural habitats in Germany. By linking MLCC estimates to the diet we explained the relevance of prey size from a viewpoint of load carrying capacity. Results: Estimates for the mean (± sd) additional portable loads were 684 g (± 237) for males and 971 g (± 235) for females, accounting for 96% and 84% of their body mass, respectively. Overall prey weight averaged higher for urban areas compared to rural ones, while the majority of prey items were between 200 and 500 g and below the estimated MLCC of both sexes, with the exception of single heavy species. Results suggest that prey use of Northern Goshawks during the breeding season is barely limited by prey transportability, since both sexes are physically capable of carrying the majority of prey species to their nest. Conclusions: Urban Northern Goshawks can exploit heavier, available prey species compared to their rural counterparts, allowing them to hunt larger prey closer to their MLCC. Ultimately, by maximizing their energy delivery to the nest, this presumably constitutes one key factor why Goshawks successfully colonized European cities. This study is the first to link estimates of physical limitations in prey transportation for a free-living raptor species to its prey composition in the light of colonizing urban environments.","PeriodicalId":55353,"journal":{"name":"Bird Study","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2021-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42054188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-02DOI: 10.1080/00063657.2022.2141192
Will T. S. Miles, M. Mellor, S. Gear, P. Harvey, G. Tyler
ABSTRACT Capsule: Numbers of moulting Common Eiders Somateria mollissima counted in Shetland during surveys from 1977 to 2019 decreased from approximately 14,500 to an estimated 3600 individuals, a 75% population decline. Aims: To report results of extensive surveys of Eiders across Shetland during the annual complete moult period, review historical surveys, and evaluate long-term population changes and the possible underlying causes for change. Methods: Extensive areas of coastal Shetland were surveyed for Eiders during the annual moult period from July to September, every one to five years from 1977 to 2019. Spatial sampling was variable between surveys from 1977 to 1993 but more systematic and standardised during all surveys from 1996 to 2019. Overall population change, changes in numbers of birds within areas categorised as either exposed or sheltered coast, and change in the proportion of adult males to females/juveniles were assessed. Results: Surveys from 1977 to 1993 indicated a 55% decrease, from approximately 14,500–6500 individuals, and surveys from 1996 to 2019 showed a 45% decrease, from an estimated 6700–3600 individuals, indicating an overall population decrease of approximately 75% from 1977 to 2019. From 1996 to 2019, Eider numbers decreased in areas of exposed coast by approximately 90% but increased by at least 70% in the more sparsely populated sheltered areas, and the overall proportion of adult males to females/juveniles reduced by one-third. Conclusion: From 1977 to 2019, a substantial decline of approximately 75% occurred in the Shetland Eider population at the time of moult. Shetland Eiders are not S. m. mollissima but morphologically and genetically akin to S. m. faeroeensis, the Faroese subspecies, the rarest subspecies worldwide, so this decline is of high conservation concern. Causes of the decline largely remain unknown, but ecological datasets on Shetland Eiders are few and detailed studies, including remote tracking of individuals’ movements throughout the year, would be worthwhile.
摘要:在1977年至2019年的调查中，设得兰群岛的换羽普通绒鸭(Somateria mollissima)的数量从约14,500只下降到约3,600只，种群数量下降了75%。目的:报告在年度完全换羽期对设得兰群岛的艾德鸭进行的广泛调查的结果，回顾历史调查，并评估长期的种群变化和可能的潜在变化原因。方法:1977 - 2019年，在每年7 - 9月的换羽期，每1 - 5年对设得兰沿海广大地区进行调查。在1977年至1993年的调查中，空间抽样是可变的，但在1996年至2019年的所有调查中，空间抽样更加系统化和标准化。评估了总体种群变化、在暴露海岸或隐蔽海岸区域内鸟类数量的变化，以及成年雄性与雌性/幼鸟比例的变化。结果:从1977年到1993年的调查显示，从大约14500 - 6500只下降了55%，从1996年到2019年的调查显示，从估计的6700-3600只下降了45%，表明从1977年到2019年，总人口减少了大约75%。从1996年到2019年，裸露海岸地区的绒鸭数量减少了约90%，但在人口较少的庇护地区，绒鸭数量增加了至少70%，成年雄性与雌性/幼鸟的总体比例减少了三分之一。结论:从1977年到2019年，设得兰绒鸭换羽时的种群数量大幅下降了约75%。设得兰绒鸭不是S. m. mollissima，但在形态和遗传上与S. m. faeroeensis(法罗亚种，世界上最稀有的亚种)相似，因此这种下降受到高度关注。数量减少的原因大部分仍不清楚，但设得兰绒鸭的生态数据很少，详细的研究，包括全年对个体活动的远程跟踪，将是值得的。
{"title":"Long-term decline and geographical variation in the numbers of moulting Common Eiders Somateria mollissima in Shetland","authors":"Will T. S. Miles, M. Mellor, S. Gear, P. Harvey, G. Tyler","doi":"10.1080/00063657.2022.2141192","DOIUrl":"https://doi.org/10.1080/00063657.2022.2141192","url":null,"abstract":"ABSTRACT Capsule: Numbers of moulting Common Eiders Somateria mollissima counted in Shetland during surveys from 1977 to 2019 decreased from approximately 14,500 to an estimated 3600 individuals, a 75% population decline. Aims: To report results of extensive surveys of Eiders across Shetland during the annual complete moult period, review historical surveys, and evaluate long-term population changes and the possible underlying causes for change. Methods: Extensive areas of coastal Shetland were surveyed for Eiders during the annual moult period from July to September, every one to five years from 1977 to 2019. Spatial sampling was variable between surveys from 1977 to 1993 but more systematic and standardised during all surveys from 1996 to 2019. Overall population change, changes in numbers of birds within areas categorised as either exposed or sheltered coast, and change in the proportion of adult males to females/juveniles were assessed. Results: Surveys from 1977 to 1993 indicated a 55% decrease, from approximately 14,500–6500 individuals, and surveys from 1996 to 2019 showed a 45% decrease, from an estimated 6700–3600 individuals, indicating an overall population decrease of approximately 75% from 1977 to 2019. From 1996 to 2019, Eider numbers decreased in areas of exposed coast by approximately 90% but increased by at least 70% in the more sparsely populated sheltered areas, and the overall proportion of adult males to females/juveniles reduced by one-third. Conclusion: From 1977 to 2019, a substantial decline of approximately 75% occurred in the Shetland Eider population at the time of moult. Shetland Eiders are not S. m. mollissima but morphologically and genetically akin to S. m. faeroeensis, the Faroese subspecies, the rarest subspecies worldwide, so this decline is of high conservation concern. Causes of the decline largely remain unknown, but ecological datasets on Shetland Eiders are few and detailed studies, including remote tracking of individuals’ movements throughout the year, would be worthwhile.","PeriodicalId":55353,"journal":{"name":"Bird Study","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2021-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46529747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-02DOI: 10.1080/00063657.2022.2124954
D. Dementavičius, Saulius Rumbutis, Rimgaudas Treinys
ABSTRACT Capsule: We found no evidence of decreased reproductive performance of the White-tailed Eagle Haliaeetus albicilla, despite ongoing population increases in an environment characterized by different types of utilized habitats. Aim: To characterize temporal and spatial variations in several components of breeding performance in an increasing White-tailed Eagle population. Methods: The breeding performance and number of pairs located in the region east of the Baltic Sea was monitored between 2005 and 2020. We analysed the trends in the numbers of pairs and several reproduction parameters for 16 years, and compared variation in breeding performance in four different habitats through application of generalized linear (mixed) models. Results: The number of White-tailed Eagle pairs increased three-fold locally between 2005 and 2020, but we found no evidence for a deterioration in breeding performance parameters (nesting success, brood size, proportion of females among nestlings, body condition of nestlings). The probability of successful nesting, nestling sex and number of nestlings in a brood were found to be similar between pairs associated with different habitats, ranging from coastal lagoons to natural waterbodies within an inland landscape. The body condition of the nestlings, however, was habitat-dependent, with the best body condition evident in nestlings reared near the Curonian Lagoon. Conclusion: Results indicate that the abundance of this predator population will continue to grow in the region east of the Baltic Sea.
{"title":"Spatial and temporal variation in breeding performance in the increasing White-tailed Eagle Haliaeetus albicilla population to the east of the Baltic Sea","authors":"D. Dementavičius, Saulius Rumbutis, Rimgaudas Treinys","doi":"10.1080/00063657.2022.2124954","DOIUrl":"https://doi.org/10.1080/00063657.2022.2124954","url":null,"abstract":"ABSTRACT Capsule: We found no evidence of decreased reproductive performance of the White-tailed Eagle Haliaeetus albicilla, despite ongoing population increases in an environment characterized by different types of utilized habitats. Aim: To characterize temporal and spatial variations in several components of breeding performance in an increasing White-tailed Eagle population. Methods: The breeding performance and number of pairs located in the region east of the Baltic Sea was monitored between 2005 and 2020. We analysed the trends in the numbers of pairs and several reproduction parameters for 16 years, and compared variation in breeding performance in four different habitats through application of generalized linear (mixed) models. Results: The number of White-tailed Eagle pairs increased three-fold locally between 2005 and 2020, but we found no evidence for a deterioration in breeding performance parameters (nesting success, brood size, proportion of females among nestlings, body condition of nestlings). The probability of successful nesting, nestling sex and number of nestlings in a brood were found to be similar between pairs associated with different habitats, ranging from coastal lagoons to natural waterbodies within an inland landscape. The body condition of the nestlings, however, was habitat-dependent, with the best body condition evident in nestlings reared near the Curonian Lagoon. Conclusion: Results indicate that the abundance of this predator population will continue to grow in the region east of the Baltic Sea.","PeriodicalId":55353,"journal":{"name":"Bird Study","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2021-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49208991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-02DOI: 10.1080/00063657.2022.2113855
D. Jarrett, J. Calladine, A. Cook, A. Upton, Jim Williams, Stuart Williams, Jared M. Wilson, Mark W. Wilson, Ian D. Woodward, E. Humphreys
ABSTRACT Capsule: Recording of behavioural responses to ferry traffic for 11 target species showed that Red-throated Diver Gavia stellata, Slavonian Grebe Podiceps auratus, and Black-throated Diver Gavia arctica were most likely to react to passing vessels. Aim: To provide information on how responses to marine traffic vary between waterbird species to inform marine spatial planning and environmental impact assessments in the near-shore environment. Methods: We recorded behavioural responses to ferry traffic for 11 target species in near-shore waters: Common Eider Somateria mollissima, Goldeneye Bucephala clangula, Long-tailed Duck Clangula hyemalis, Velvet Scoter Melanitta fusca, Red-breasted Merganser Mergus serrator, Black-throated Diver, Great Northern Diver Gavia immer, Red-throated Diver, European Shag Gulosus aristotelis, Slavonian Grebe and Black Guillemot Cepphus grylle. Responses were analysed using generalized linear models and mixed models. Results: Red-throated Diver, Black-throated Diver and Slavonian Grebe were the most likely species to exhibit a response to passing vessels. While Red-throated Divers and Slavonian Grebes were highly likely to flush, Black-throated Divers and Great Northern Divers rarely took flight, instead favouring swim or dive responses. In rougher sea conditions birds were more likely to take flight, and the propensity to respond declined across the wintering period. Conclusions: This research provides comparative evidence on the behavioural responses of waterbirds to marine traffic. The results support previous studies which highlighted the high sensitivity of diver species to disturbance and provide new evidence that Slavonian Grebe may also be a high sensitivity species.
{"title":"Behavioural responses of non-breeding waterbirds to marine traffic in the near-shore environment","authors":"D. Jarrett, J. Calladine, A. Cook, A. Upton, Jim Williams, Stuart Williams, Jared M. Wilson, Mark W. Wilson, Ian D. Woodward, E. Humphreys","doi":"10.1080/00063657.2022.2113855","DOIUrl":"https://doi.org/10.1080/00063657.2022.2113855","url":null,"abstract":"ABSTRACT Capsule: Recording of behavioural responses to ferry traffic for 11 target species showed that Red-throated Diver Gavia stellata, Slavonian Grebe Podiceps auratus, and Black-throated Diver Gavia arctica were most likely to react to passing vessels. Aim: To provide information on how responses to marine traffic vary between waterbird species to inform marine spatial planning and environmental impact assessments in the near-shore environment. Methods: We recorded behavioural responses to ferry traffic for 11 target species in near-shore waters: Common Eider Somateria mollissima, Goldeneye Bucephala clangula, Long-tailed Duck Clangula hyemalis, Velvet Scoter Melanitta fusca, Red-breasted Merganser Mergus serrator, Black-throated Diver, Great Northern Diver Gavia immer, Red-throated Diver, European Shag Gulosus aristotelis, Slavonian Grebe and Black Guillemot Cepphus grylle. Responses were analysed using generalized linear models and mixed models. Results: Red-throated Diver, Black-throated Diver and Slavonian Grebe were the most likely species to exhibit a response to passing vessels. While Red-throated Divers and Slavonian Grebes were highly likely to flush, Black-throated Divers and Great Northern Divers rarely took flight, instead favouring swim or dive responses. In rougher sea conditions birds were more likely to take flight, and the propensity to respond declined across the wintering period. Conclusions: This research provides comparative evidence on the behavioural responses of waterbirds to marine traffic. The results support previous studies which highlighted the high sensitivity of diver species to disturbance and provide new evidence that Slavonian Grebe may also be a high sensitivity species.","PeriodicalId":55353,"journal":{"name":"Bird Study","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2021-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47255928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-02DOI: 10.1080/00063657.2022.2113856
D. Mazzoni, J. Pascual, L. Arroyo, T. Montalvo, J. González‐Solís, J. C. Senar
ABSTRACT Capsule: Previous observations in Barcelona and other cities showed that approximately 40% of the food ingested by adult Monk Parakeets Myiopsitta monachus is of anthropogenic origin. Here we show that this type of food source is also used for feeding nestlings. Aims: To quantify the proportion of anthropogenic food within the diet of nestling Monk Parakeets, a non-native species in Barcelona. Methods: We analysed stable isotopes of 13C and 15N in feathers of Monk Parakeet nestlings collected in the Barcelona city area. We also sampled potential food sources ingested by Monk Parakeets to reconstruct the nestling diet using Bayesian mixing models with MixSIAR. Results: Almost 30% of the nestlings’ diet was composed of anthropogenic food. Conclusions: Since food availability is a major factor regulating population growth, we propose educating the general public to reduce the food supply for the species and ultimately limit its population growth.
{"title":"The diet of Monk Parakeet Myiopsitta monachus nestlings in an urban area: a study using stable isotopes","authors":"D. Mazzoni, J. Pascual, L. Arroyo, T. Montalvo, J. González‐Solís, J. C. Senar","doi":"10.1080/00063657.2022.2113856","DOIUrl":"https://doi.org/10.1080/00063657.2022.2113856","url":null,"abstract":"ABSTRACT Capsule: Previous observations in Barcelona and other cities showed that approximately 40% of the food ingested by adult Monk Parakeets Myiopsitta monachus is of anthropogenic origin. Here we show that this type of food source is also used for feeding nestlings. Aims: To quantify the proportion of anthropogenic food within the diet of nestling Monk Parakeets, a non-native species in Barcelona. Methods: We analysed stable isotopes of 13C and 15N in feathers of Monk Parakeet nestlings collected in the Barcelona city area. We also sampled potential food sources ingested by Monk Parakeets to reconstruct the nestling diet using Bayesian mixing models with MixSIAR. Results: Almost 30% of the nestlings’ diet was composed of anthropogenic food. Conclusions: Since food availability is a major factor regulating population growth, we propose educating the general public to reduce the food supply for the species and ultimately limit its population growth.","PeriodicalId":55353,"journal":{"name":"Bird Study","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2021-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42968564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-03DOI: 10.1080/00063657.2022.2103514
S. P. Campbell, Michael E. Akresh, Neil A. Gifford, David I. King
ABSTRACT Capsule In a single-year study, attaching geolocators to male Prairie Warblers Setophaga discolor, one of the smallest species to date to carry geolocators, decreased return rates but had no effect on inter-annual territory fidelity. Aims To examine the effects of light-level geolocators on return rates and inter-annual territory fidelity of adult, male Prairie Warblers migrating to and from their non-breeding grounds. Methods During the 2016 breeding season we captured adult male Prairie Warblers at two sites in northeastern USA and attached geolocators and colour rings to one group of birds, and only colour rings to another group of birds. During the 2017 breeding season, we estimated return rates to the sites and inter-annual territory fidelity (i.e. distance between territory locations from one year to the next) for the birds that returned to the sites. We compared return rates and territory fidelity between birds with and without geolocators. Results Geolocators significantly decreased return rates of male Prairie Warblers to the study sites by 0.18 (95% credible interval [CI]: −0.37 to 0.01) from 2016 to 2017. Birds that returned exhibited a range of distances between estimated locations of territories in each year (7–2104 m), but the differences in distances between birds with and without geolocators were not statistically significant. Conclusion Although return rates were lower for Prairie Warblers with geolocators, these effects should not necessarily disqualify their use. Rather, the magnitude of the negative effects on individuals needs to be considered against the benefits and reliability of the information gained for the population or species. We recommend the effects of geolocators and other tracking tags should be studied and reported in conjunction with the main objectives of the study for which the tags are being used.
{"title":"Effects of light-level geolocators on return rates and inter-annual territory fidelity of Prairie Warblers Setophaga discolor","authors":"S. P. Campbell, Michael E. Akresh, Neil A. Gifford, David I. King","doi":"10.1080/00063657.2022.2103514","DOIUrl":"https://doi.org/10.1080/00063657.2022.2103514","url":null,"abstract":"ABSTRACT Capsule In a single-year study, attaching geolocators to male Prairie Warblers Setophaga discolor, one of the smallest species to date to carry geolocators, decreased return rates but had no effect on inter-annual territory fidelity. Aims To examine the effects of light-level geolocators on return rates and inter-annual territory fidelity of adult, male Prairie Warblers migrating to and from their non-breeding grounds. Methods During the 2016 breeding season we captured adult male Prairie Warblers at two sites in northeastern USA and attached geolocators and colour rings to one group of birds, and only colour rings to another group of birds. During the 2017 breeding season, we estimated return rates to the sites and inter-annual territory fidelity (i.e. distance between territory locations from one year to the next) for the birds that returned to the sites. We compared return rates and territory fidelity between birds with and without geolocators. Results Geolocators significantly decreased return rates of male Prairie Warblers to the study sites by 0.18 (95% credible interval [CI]: −0.37 to 0.01) from 2016 to 2017. Birds that returned exhibited a range of distances between estimated locations of territories in each year (7–2104 m), but the differences in distances between birds with and without geolocators were not statistically significant. Conclusion Although return rates were lower for Prairie Warblers with geolocators, these effects should not necessarily disqualify their use. Rather, the magnitude of the negative effects on individuals needs to be considered against the benefits and reliability of the information gained for the population or species. We recommend the effects of geolocators and other tracking tags should be studied and reported in conjunction with the main objectives of the study for which the tags are being used.","PeriodicalId":55353,"journal":{"name":"Bird Study","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2021-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45588596","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-03DOI: 10.1080/00063657.2022.2096874
R. Valle, A. Baaloudj, F. Scarton
ABSTRACT This study describes a new method for counting breeding Purple Herons Ardea purpurea on a large wetland complex (Po Delta, Italy) using Google Earth satellite imagery in comparison to traditional ground counts in 2017. Google Earth counts provide an accurate, rapid, and inexpensive method for estimating the breeding population of Purple Herons, both saving time and increasing count accuracy in comparison to ground counts.
{"title":"A new method for surveying Purple Heron Ardea purpurea colonies using Google Earth","authors":"R. Valle, A. Baaloudj, F. Scarton","doi":"10.1080/00063657.2022.2096874","DOIUrl":"https://doi.org/10.1080/00063657.2022.2096874","url":null,"abstract":"ABSTRACT This study describes a new method for counting breeding Purple Herons Ardea purpurea on a large wetland complex (Po Delta, Italy) using Google Earth satellite imagery in comparison to traditional ground counts in 2017. Google Earth counts provide an accurate, rapid, and inexpensive method for estimating the breeding population of Purple Herons, both saving time and increasing count accuracy in comparison to ground counts.","PeriodicalId":55353,"journal":{"name":"Bird Study","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2021-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42604822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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：