Pub Date : 2023-03-19DOI: 10.1080/01584197.2023.2182224
Trey C. Hendrix, Facundo Fernandez‐Duque, Sarah Toner, Lauren G. Hitt, Robin G. Thady, Megan Massa, Samantha J. Hagler, Margaux Armfield, Nathalie Clarke, Phoebe Honscheid, Sarah Khalil, C. Hawkins, Samantha M. Lantz, Joseph F. Welklin, J. Swaddle, M. S. Webster, J. Karubian
ABSTRACT During the breeding season, male Red-backed Fairywrens (Malurus melanocephalus) can exhibit ornamented (red-black) or unornamented (brown, resembling females and juveniles) plumage. These distinct plumage types represent alternative reproductive tactics and are associated with behavioural differences during the breeding season. However, we lack an understanding of whether and how these plumage types may be associated with behavioural differences during non-reproductive parts of the year. To fill this knowledge gap, we carried out behavioural observations during the nonbreeding season across three years. We hypothesised that ornamented plumage remains associated with mate attraction behaviours outside of the breeding season. We examined the investment of ornamented, moulting, and unornamented males in social behaviours and found that the three plumage types were largely similar in their behaviour except ornamented males courted and, to a lesser extent, allopreened at higher rates than unornamented males. Since concurrent work in the same study population demonstrates increased extra-pair fitness for males who moult into ornamented plumage early, we speculate that ornamentation and courtship behaviour may serve a mate attraction function outside of the breeding season. We argue that future studies should consider individual-level behavioural monitoring throughout the annual cycle to better quantify the complex selection pressures that lead to the coevolution of plumage moult and alternative reproductive tactics in this system.
{"title":"Behavioural differences between ornamented and unornamented male Red-backed Fairywrens (Malurus melanocephalus) in the nonbreeding season","authors":"Trey C. Hendrix, Facundo Fernandez‐Duque, Sarah Toner, Lauren G. Hitt, Robin G. Thady, Megan Massa, Samantha J. Hagler, Margaux Armfield, Nathalie Clarke, Phoebe Honscheid, Sarah Khalil, C. Hawkins, Samantha M. Lantz, Joseph F. Welklin, J. Swaddle, M. S. Webster, J. Karubian","doi":"10.1080/01584197.2023.2182224","DOIUrl":"https://doi.org/10.1080/01584197.2023.2182224","url":null,"abstract":"ABSTRACT During the breeding season, male Red-backed Fairywrens (Malurus melanocephalus) can exhibit ornamented (red-black) or unornamented (brown, resembling females and juveniles) plumage. These distinct plumage types represent alternative reproductive tactics and are associated with behavioural differences during the breeding season. However, we lack an understanding of whether and how these plumage types may be associated with behavioural differences during non-reproductive parts of the year. To fill this knowledge gap, we carried out behavioural observations during the nonbreeding season across three years. We hypothesised that ornamented plumage remains associated with mate attraction behaviours outside of the breeding season. We examined the investment of ornamented, moulting, and unornamented males in social behaviours and found that the three plumage types were largely similar in their behaviour except ornamented males courted and, to a lesser extent, allopreened at higher rates than unornamented males. Since concurrent work in the same study population demonstrates increased extra-pair fitness for males who moult into ornamented plumage early, we speculate that ornamentation and courtship behaviour may serve a mate attraction function outside of the breeding season. We argue that future studies should consider individual-level behavioural monitoring throughout the annual cycle to better quantify the complex selection pressures that lead to the coevolution of plumage moult and alternative reproductive tactics in this system.","PeriodicalId":50532,"journal":{"name":"Emu-Austral Ornithology","volume":"48 1","pages":"176 - 181"},"PeriodicalIF":1.3,"publicationDate":"2023-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86200002","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 : 2023-03-16DOI: 10.1080/01584197.2023.2181185
Elen Shute, Alice M. Clement, G. Prideaux
ABSTRACT The Night Parrot Pezoporus occidentalis is a critically endangered, elusive, nocturnal bird that is difficult to study in the field. Much is unknown about its biology, including how it navigates at night. A previous investigation of the eye and brain revealed that it likely has poor nocturnal vision, but its other sensory abilities, and overall skull anatomy, have not yet been investigated. This osteological study, based on micro-CT-scans of the holotype, describes and compares the anatomy of the Night Parrot skull, and identifies its possible ecological adaptations. Specialised ear anatomy suggests that the Night Parrot has enhanced acoustic abilities, in contrast with its diurnal congener P. wallicus and the only other nocturnal parrot, the Kakapo Strigops habroptila. The Night Parrot’s uniquely enlarged exoccipital bones may amplify sound, and bilateral ear asymmetry, not identified in any other parrot species, likely enhances its directional hearing, as in many species of owl. Enlarged exoccipitals displace the zygomatic processes and constrain orbit size, suggesting an evolutionary trade-off between hearing and vision. The auditory abilities of the species require deeper investigation, but our anatomical observations indicate that the potential impacts of noise disturbance may warrant consideration in Night Parrot conservation strategies as a precaution.
{"title":"Cranial adaptations of the Night Parrot (Psittaculidae: Pezoporus occidentalis), a cryptic nocturnal bird","authors":"Elen Shute, Alice M. Clement, G. Prideaux","doi":"10.1080/01584197.2023.2181185","DOIUrl":"https://doi.org/10.1080/01584197.2023.2181185","url":null,"abstract":"ABSTRACT The Night Parrot Pezoporus occidentalis is a critically endangered, elusive, nocturnal bird that is difficult to study in the field. Much is unknown about its biology, including how it navigates at night. A previous investigation of the eye and brain revealed that it likely has poor nocturnal vision, but its other sensory abilities, and overall skull anatomy, have not yet been investigated. This osteological study, based on micro-CT-scans of the holotype, describes and compares the anatomy of the Night Parrot skull, and identifies its possible ecological adaptations. Specialised ear anatomy suggests that the Night Parrot has enhanced acoustic abilities, in contrast with its diurnal congener P. wallicus and the only other nocturnal parrot, the Kakapo Strigops habroptila. The Night Parrot’s uniquely enlarged exoccipital bones may amplify sound, and bilateral ear asymmetry, not identified in any other parrot species, likely enhances its directional hearing, as in many species of owl. Enlarged exoccipitals displace the zygomatic processes and constrain orbit size, suggesting an evolutionary trade-off between hearing and vision. The auditory abilities of the species require deeper investigation, but our anatomical observations indicate that the potential impacts of noise disturbance may warrant consideration in Night Parrot conservation strategies as a precaution.","PeriodicalId":50532,"journal":{"name":"Emu-Austral Ornithology","volume":"61 1","pages":"129 - 139"},"PeriodicalIF":1.3,"publicationDate":"2023-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83018076","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 : 2023-02-26DOI: 10.1080/01584197.2023.2182223
Elizabeth Dixon, B. Smit
ABSTRACT Birds need to maintain their hydration by either gaining water from their food or by drinking surface water. Many arid-zone birds do not need to consume surface water to maintain body condition. Conservationists need to better understand avian use of surface water sources to inform management plans in a warming world. In this study, we explored the use of Facebook’s image search as a tool to predict interspecific variations in avian surface water use. There was a significant correlation between the proportion of Facebook photographs of each species associated with surface water, and surface water use indices for these species based on published field studies. These findings suggest that Facebook may be a useful source of data for determining the dependence of bird species on surface water. Future research could address the potential for Facebook and other social media platforms for answering a range of ecological questions relating to avian water dependency.
{"title":"Using Facebook user photos to quantify surface water dependency in Southern African arid-zone bird species","authors":"Elizabeth Dixon, B. Smit","doi":"10.1080/01584197.2023.2182223","DOIUrl":"https://doi.org/10.1080/01584197.2023.2182223","url":null,"abstract":"ABSTRACT Birds need to maintain their hydration by either gaining water from their food or by drinking surface water. Many arid-zone birds do not need to consume surface water to maintain body condition. Conservationists need to better understand avian use of surface water sources to inform management plans in a warming world. In this study, we explored the use of Facebook’s image search as a tool to predict interspecific variations in avian surface water use. There was a significant correlation between the proportion of Facebook photographs of each species associated with surface water, and surface water use indices for these species based on published field studies. These findings suggest that Facebook may be a useful source of data for determining the dependence of bird species on surface water. Future research could address the potential for Facebook and other social media platforms for answering a range of ecological questions relating to avian water dependency.","PeriodicalId":50532,"journal":{"name":"Emu-Austral Ornithology","volume":"185 1","pages":"170 - 175"},"PeriodicalIF":1.3,"publicationDate":"2023-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75767708","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 : 2023-02-21DOI: 10.1080/01584197.2023.2173611
Sara R. Seibert, L. Joseph, Jon Bowers, Philip Lavretsky, A. Drew, I. Mason, D. Roshier, Bulisa Iova, J. Peters
ABSTRACT Biogeographic barriers can restrict gene flow, but variation in ecological drivers of dispersal influences the effectiveness of these barriers among different species. Detailed information about the genetic connectivity and movement of waterfowl across biogeographic barriers in northern Australia and Papua New Guinea is limited. We compared genetic connectivity for four species of Australasian waterfowl that vary in their capacity and predisposition for dispersal: Radjah Shelduck (Radjah radjah), Wandering Whistling Duck (Dendrocygna arcuata), Green Pygmy Goose (Nettapus pulchellus), and Pacific Black Duck (Anas superciliosa). We obtained >3,700 loci from double-digest restriction-associated DNA sequencing for 15 to 40 individuals per species and found idiosyncratic patterns of population structure among the four species. The mostly sedentary Radjah Shelduck exhibited clear genetic differences between New Guinea and Australia as well as among locations within Australia. Although the population structure was consistent with isolation by distance, the Torres Strait and Carpentaria Barrier contributed more to genetic differences than geographic distance alone. In contrast, the presumed sedentary Green Pygmy Goose did not show obvious structure. Likewise, populations of the more dispersive Wandering Whistling Duck and Pacific Black Duck were unstructured and genetically indistinguishable between southern New Guinea and northern Australia. Our data suggest that some Australo-Papuan biogeographical barriers are insufficient to impede gene flow in waterfowl species capable of dispersing great distances. In sedentary species like the Radjah Shelduck, these barriers, perhaps coupled with its ecology and natural history, restrict gene flow. Our findings bring new insight into the population ecology of Australo-Papuan waterfowl.
{"title":"Population genomics and phylogeography of four Australasian waterfowl","authors":"Sara R. Seibert, L. Joseph, Jon Bowers, Philip Lavretsky, A. Drew, I. Mason, D. Roshier, Bulisa Iova, J. Peters","doi":"10.1080/01584197.2023.2173611","DOIUrl":"https://doi.org/10.1080/01584197.2023.2173611","url":null,"abstract":"ABSTRACT Biogeographic barriers can restrict gene flow, but variation in ecological drivers of dispersal influences the effectiveness of these barriers among different species. Detailed information about the genetic connectivity and movement of waterfowl across biogeographic barriers in northern Australia and Papua New Guinea is limited. We compared genetic connectivity for four species of Australasian waterfowl that vary in their capacity and predisposition for dispersal: Radjah Shelduck (Radjah radjah), Wandering Whistling Duck (Dendrocygna arcuata), Green Pygmy Goose (Nettapus pulchellus), and Pacific Black Duck (Anas superciliosa). We obtained >3,700 loci from double-digest restriction-associated DNA sequencing for 15 to 40 individuals per species and found idiosyncratic patterns of population structure among the four species. The mostly sedentary Radjah Shelduck exhibited clear genetic differences between New Guinea and Australia as well as among locations within Australia. Although the population structure was consistent with isolation by distance, the Torres Strait and Carpentaria Barrier contributed more to genetic differences than geographic distance alone. In contrast, the presumed sedentary Green Pygmy Goose did not show obvious structure. Likewise, populations of the more dispersive Wandering Whistling Duck and Pacific Black Duck were unstructured and genetically indistinguishable between southern New Guinea and northern Australia. Our data suggest that some Australo-Papuan biogeographical barriers are insufficient to impede gene flow in waterfowl species capable of dispersing great distances. In sedentary species like the Radjah Shelduck, these barriers, perhaps coupled with its ecology and natural history, restrict gene flow. Our findings bring new insight into the population ecology of Australo-Papuan waterfowl.","PeriodicalId":50532,"journal":{"name":"Emu-Austral Ornithology","volume":"72 1","pages":"105 - 117"},"PeriodicalIF":1.3,"publicationDate":"2023-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84990845","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 : 2023-02-19DOI: 10.1080/01584197.2023.2172735
Christopher MacColl, Nick Leseberg, R. Seaton, S. Murphy, J. Watson
ABSTRACT Australia’s Red Goshawk (Erythrotriorchis radiatus) is a taxonomically distinct raptor endemic to the tropics and sub-tropics of eastern and northern Australia, and the Australian mainland’s rarest bird of prey. Classified as Vulnerable when legislation was first enacted in 1992, the species’ status and distribution remain unclear, and it is possibly declining based on limited surveys. However, no comprehensive analysis of its range-wide population trends has ever been undertaken, creating a knowledge gap which potentially delays urgent conservation management. Here, we bridge that knowledge gap. We compile a comprehensive dataset of 1,679 occurrence records spanning the species’ historical range, develop a novel method that overcomes reporting biases centred around nest locations, then identify population trends between 1978 and 2020 at national, state, and regional scales. Our results suggest that the species has declined significantly across eastern Australia and is likely locally extinct in many regions. We estimate the Red Goshawk has disappeared from 34% of its breeding range over the last four decades, and probably persists at extremely low density, if at all, over an additional 29.7% of its breeding range. These results demonstrate the species’ declining population trajectory at multiple scales for the first time and provide further evidence for its up listing under Australian federal legislation to Endangered, using IUCN Red List criterion C2a(ii): small population size and decline. We recommend population surveys and monitoring coupled with targeted research to better understand population trajectories and determine which threats are driving this unique species’ decline.
{"title":"Rapid and recent range collapse of Australia’s Red Goshawk Erythrotriorchis radiatus","authors":"Christopher MacColl, Nick Leseberg, R. Seaton, S. Murphy, J. Watson","doi":"10.1080/01584197.2023.2172735","DOIUrl":"https://doi.org/10.1080/01584197.2023.2172735","url":null,"abstract":"ABSTRACT Australia’s Red Goshawk (Erythrotriorchis radiatus) is a taxonomically distinct raptor endemic to the tropics and sub-tropics of eastern and northern Australia, and the Australian mainland’s rarest bird of prey. Classified as Vulnerable when legislation was first enacted in 1992, the species’ status and distribution remain unclear, and it is possibly declining based on limited surveys. However, no comprehensive analysis of its range-wide population trends has ever been undertaken, creating a knowledge gap which potentially delays urgent conservation management. Here, we bridge that knowledge gap. We compile a comprehensive dataset of 1,679 occurrence records spanning the species’ historical range, develop a novel method that overcomes reporting biases centred around nest locations, then identify population trends between 1978 and 2020 at national, state, and regional scales. Our results suggest that the species has declined significantly across eastern Australia and is likely locally extinct in many regions. We estimate the Red Goshawk has disappeared from 34% of its breeding range over the last four decades, and probably persists at extremely low density, if at all, over an additional 29.7% of its breeding range. These results demonstrate the species’ declining population trajectory at multiple scales for the first time and provide further evidence for its up listing under Australian federal legislation to Endangered, using IUCN Red List criterion C2a(ii): small population size and decline. We recommend population surveys and monitoring coupled with targeted research to better understand population trajectories and determine which threats are driving this unique species’ decline.","PeriodicalId":50532,"journal":{"name":"Emu-Austral Ornithology","volume":"86 11 1","pages":"93 - 104"},"PeriodicalIF":1.3,"publicationDate":"2023-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84005172","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 : 2023-02-06DOI: 10.1080/01584197.2023.2174882
Lolita Rynkowski, Matthew Bennion, C. Browne, J. Cockrem, P. Ross
ABSTRACT In northern New Zealand, there is speculation that predation by a recovering shorebird, the South Island Pied Oystercatcher (Haematopus finschi), has caused the continuing decline of an endemic surf clam, the toheroa (Paphies ventricosa). Consequently, there have been requests by the public for these protected birds to be culled to protect and restore the toheroa. To better inform management and decision-making for these species we set out to understand the impact of oystercatcher predation on toheroa at Ripiro Beach in New Zealand. A study was conducted to establish the spatio-temporal overlap of toheroa and oystercatcher distributions, determine oystercatcher prey selection, and assess the impacts of oystercatcher predation on toheroa population size structure. Monthly surveys over a 12-month period indicated limited spatial overlap between the two species, and that most toheroa beds on Ripiro Beach are not subjected to oystercatcher predation. In areas where oystercatchers and toheroa co-occurred, oystercatchers consumed a variety of prey including polychaetes, small and medium-sized toheroa and a non-threatened surf clam (P. subtriangulata). While oystercatchers do feed on toheroa (and may be capable of locally reducing abundance of small toheroa in a population), feeding on larger individuals (>50 mm in length) was not observed. These results suggest that culling of oystercatchers would be of no benefit for the recovery of toheroa populations. It is likely that less obvious factors are impeding the recovery of toheroa in New Zealand. This study highlights the importance of understanding predator-prey interactions before implementing management actions such as lethal control.
{"title":"The impact of predation by South Island Pied Oystercatchers (Haematopus finschi) on a protected shellfish, the toheroa (Paphies ventricosa), in northern New Zealand","authors":"Lolita Rynkowski, Matthew Bennion, C. Browne, J. Cockrem, P. Ross","doi":"10.1080/01584197.2023.2174882","DOIUrl":"https://doi.org/10.1080/01584197.2023.2174882","url":null,"abstract":"ABSTRACT In northern New Zealand, there is speculation that predation by a recovering shorebird, the South Island Pied Oystercatcher (Haematopus finschi), has caused the continuing decline of an endemic surf clam, the toheroa (Paphies ventricosa). Consequently, there have been requests by the public for these protected birds to be culled to protect and restore the toheroa. To better inform management and decision-making for these species we set out to understand the impact of oystercatcher predation on toheroa at Ripiro Beach in New Zealand. A study was conducted to establish the spatio-temporal overlap of toheroa and oystercatcher distributions, determine oystercatcher prey selection, and assess the impacts of oystercatcher predation on toheroa population size structure. Monthly surveys over a 12-month period indicated limited spatial overlap between the two species, and that most toheroa beds on Ripiro Beach are not subjected to oystercatcher predation. In areas where oystercatchers and toheroa co-occurred, oystercatchers consumed a variety of prey including polychaetes, small and medium-sized toheroa and a non-threatened surf clam (P. subtriangulata). While oystercatchers do feed on toheroa (and may be capable of locally reducing abundance of small toheroa in a population), feeding on larger individuals (>50 mm in length) was not observed. These results suggest that culling of oystercatchers would be of no benefit for the recovery of toheroa populations. It is likely that less obvious factors are impeding the recovery of toheroa in New Zealand. This study highlights the importance of understanding predator-prey interactions before implementing management actions such as lethal control.","PeriodicalId":50532,"journal":{"name":"Emu-Austral Ornithology","volume":"94 1","pages":"118 - 128"},"PeriodicalIF":1.3,"publicationDate":"2023-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85255653","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 : 2023-01-02DOI: 10.1080/01584197.2022.2160358
Lia Nahomi Kajiki, Mariana de-Carvalho, Paulo Victor Resende Dos Santos, Samara de Albuquerque Teixeira, R. Macedo
ABSTRACT Neotropical manakins exhibit polygynous lekking systems in which males do not provide paternal care and exhibit elaborate courtship displays. Despite familial patterns, some historical field observations suggested that the Helmeted Manakin (Antilophia galeata) has evolved territoriality rather than lekking and a socially monogamous mating system. Furthermore, the evidence so far does not allow a clear understanding of the role played by resources, such as nesting sites and male behaviour in shaping the mating system in this species. Our objectives were to verify whether territorial behaviour occurs in the Helmeted Manakin and to provide a preliminary assessment of this species’ hypothesised social monogamy. Using an experimental approach with simulated territorial intrusions, we demonstrated that males in this species hold individual territories with nesting sites but do not provide parental care, similar to its congener, the Araripe Manakin (Antilophia bokermanni). Males’ responses occurred more aggressively in central areas of territories. Larger home ranges encompassed the smaller defended territories and the male display consists of repeated circular flights within the territory. Our results indicate that the Helmeted Manakin has a polygamous mating system. However, we suggest the species is better classified within the continuum of a resource-defence exploded-lek mating system. The distinct environmental conditions in which the species evolved may have played a significant role in modifying its behaviour, resulting in patterns that deviate from the typical lekking system found among manakins. This study highlights the importance of investigating atypical manakins to further our understanding of alternative reproductive tactics among birds.
{"title":"Individual territoriality in lekking species: the case of the Helmeted Manakin","authors":"Lia Nahomi Kajiki, Mariana de-Carvalho, Paulo Victor Resende Dos Santos, Samara de Albuquerque Teixeira, R. Macedo","doi":"10.1080/01584197.2022.2160358","DOIUrl":"https://doi.org/10.1080/01584197.2022.2160358","url":null,"abstract":"ABSTRACT Neotropical manakins exhibit polygynous lekking systems in which males do not provide paternal care and exhibit elaborate courtship displays. Despite familial patterns, some historical field observations suggested that the Helmeted Manakin (Antilophia galeata) has evolved territoriality rather than lekking and a socially monogamous mating system. Furthermore, the evidence so far does not allow a clear understanding of the role played by resources, such as nesting sites and male behaviour in shaping the mating system in this species. Our objectives were to verify whether territorial behaviour occurs in the Helmeted Manakin and to provide a preliminary assessment of this species’ hypothesised social monogamy. Using an experimental approach with simulated territorial intrusions, we demonstrated that males in this species hold individual territories with nesting sites but do not provide parental care, similar to its congener, the Araripe Manakin (Antilophia bokermanni). Males’ responses occurred more aggressively in central areas of territories. Larger home ranges encompassed the smaller defended territories and the male display consists of repeated circular flights within the territory. Our results indicate that the Helmeted Manakin has a polygamous mating system. However, we suggest the species is better classified within the continuum of a resource-defence exploded-lek mating system. The distinct environmental conditions in which the species evolved may have played a significant role in modifying its behaviour, resulting in patterns that deviate from the typical lekking system found among manakins. This study highlights the importance of investigating atypical manakins to further our understanding of alternative reproductive tactics among birds.","PeriodicalId":50532,"journal":{"name":"Emu-Austral Ornithology","volume":"228 1","pages":"35 - 48"},"PeriodicalIF":1.3,"publicationDate":"2023-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79574322","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 : 2023-01-02DOI: 10.1080/01584197.2022.2161914
H. Schultz, P. Battley, S. Bury, Kevin Chang, S. M. Ismar-Rebitz, A. Gaskett, T. Dennis, R. Hohnhold, GRAEME A. Taylor, R. Paul Scofield, M. Rayner, A. Tennyson, A. Hemmings, C. Millar
ABSTRACT Long-term changes in the life history and behaviour of seabirds during the non-breeding season can reflect shifts in environmental conditions. However, long-term marine studies are scarce, particularly on southern hemisphere seabirds. Here, we used moult scores from 86 Brown Skuas (Stercorarius antarcticus lonnbergi), a large predatory seabird breeding on the Chatham Islands, Aotearoa/New Zealand to model both the timing and duration of primary feather moult. In addition, we analysed stable isotope values (δ13C and δ15N) from 62 modern (2014–16) and ten museum tail feathers. These data provide insights into the non-breeding behaviour of Brown Skua. Interestingly, our results show that the primary feather moult occurred prior to birds departing the colony, starting on average on 2 January ± 5 days (SE). The average start of primary feather moult occurred five days prior to the end of breeding (7 January ± 10 days (SD)) and 42 days before the birds departed the colony (13 February ± 11 days (SD)). The average duration of primary feather moult was 189 ± 14 days (SE). Importantly, low δ13C values in four females suggested that tail feather moult might also occur while skuas are at the colony. There was no difference in tail feather δ13C and δ15N values between any pairwise comparison of modern and museum years. However, values of δ15N from tail feathers sampled in 2014 were different from those sampled in 2015 and 2016. This large annual variation in δ15N values from tail feathers over such a short period makes long-term comparisons difficult to interpret, particularly between years with low sample sizes. While the stable isotope analyses of tail feathers are informative, we recommend future studies of skuas sample the primary coverts rather than tail feathers.
在非繁殖季节,海鸟的生活史和行为的长期变化可以反映环境条件的变化。然而,长期的海洋研究很少,特别是对南半球海鸟的研究。在这里,我们使用了86只棕色贼鸥(Stercorarius antarcticus lonnbergi)的换羽评分,这是一种在新西兰奥特罗阿查塔姆群岛繁殖的大型掠食性海鸟,以模拟初级羽毛换羽的时间和持续时间。此外,我们分析了62根现代(2014 - 2016)和10根博物馆尾羽的稳定同位素值(δ13C和δ15N)。这些数据提供了对褐贼鸥非繁殖行为的深入了解。有趣的是,我们的研究结果表明,初生羽毛蜕皮发生在鸟类离开群落之前,平均在1月2日±5天(SE)开始。初生羽毛平均在繁殖结束前5天(1月7日±10天)和离群前42天(2月13日±11天)开始换羽。初生羽毛平均换羽时间为189±14 d (SE)。重要的是,4只母贼鸥的低δ13C值表明,当贼鸥在殖民地时,尾羽也可能发生换羽。现代年和博物馆年的尾羽δ13C和δ15N值两两比较无显著差异。然而,2014年尾羽的δ15N值与2015年和2016年不同。在如此短的时间内,尾羽δ15N值的年变化如此之大,使得长期比较难以解释,特别是在样本量小的年份之间。虽然尾羽的稳定同位素分析提供了丰富的信息,但我们建议未来的贼鸥研究取样于主要的转换层,而不是尾羽。
{"title":"Non-breeding behaviour in the Brown Skua (Stercorarius antarcticus lonnbergi): insights from modelling moulting patterns and stable isotope analyses","authors":"H. Schultz, P. Battley, S. Bury, Kevin Chang, S. M. Ismar-Rebitz, A. Gaskett, T. Dennis, R. Hohnhold, GRAEME A. Taylor, R. Paul Scofield, M. Rayner, A. Tennyson, A. Hemmings, C. Millar","doi":"10.1080/01584197.2022.2161914","DOIUrl":"https://doi.org/10.1080/01584197.2022.2161914","url":null,"abstract":"ABSTRACT Long-term changes in the life history and behaviour of seabirds during the non-breeding season can reflect shifts in environmental conditions. However, long-term marine studies are scarce, particularly on southern hemisphere seabirds. Here, we used moult scores from 86 Brown Skuas (Stercorarius antarcticus lonnbergi), a large predatory seabird breeding on the Chatham Islands, Aotearoa/New Zealand to model both the timing and duration of primary feather moult. In addition, we analysed stable isotope values (δ13C and δ15N) from 62 modern (2014–16) and ten museum tail feathers. These data provide insights into the non-breeding behaviour of Brown Skua. Interestingly, our results show that the primary feather moult occurred prior to birds departing the colony, starting on average on 2 January ± 5 days (SE). The average start of primary feather moult occurred five days prior to the end of breeding (7 January ± 10 days (SD)) and 42 days before the birds departed the colony (13 February ± 11 days (SD)). The average duration of primary feather moult was 189 ± 14 days (SE). Importantly, low δ13C values in four females suggested that tail feather moult might also occur while skuas are at the colony. There was no difference in tail feather δ13C and δ15N values between any pairwise comparison of modern and museum years. However, values of δ15N from tail feathers sampled in 2014 were different from those sampled in 2015 and 2016. This large annual variation in δ15N values from tail feathers over such a short period makes long-term comparisons difficult to interpret, particularly between years with low sample sizes. While the stable isotope analyses of tail feathers are informative, we recommend future studies of skuas sample the primary coverts rather than tail feathers.","PeriodicalId":50532,"journal":{"name":"Emu-Austral Ornithology","volume":"34 1","pages":"49 - 59"},"PeriodicalIF":1.3,"publicationDate":"2023-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81971290","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 : 2023-01-02DOI: 10.1080/01584197.2022.2153700
M. S. Vazquez, G. Amico
ABSTRACT Multiple factors influence predation risk, ranging from habitat conditions to the composition and behaviour of predators. Although these factors are well documented for forest ecosystems, there is little evidence for wetlands, especially within Patagonia. Using artificial nests and camera traps, we documented the nest predation rates and predator assemblage of birds nesting in wetlands of the Patagonian steppe. We also determined the effect of vegetation cover on nest survival and studied the variation in predator groups according to nest placement: nests located in an open wetland, peripheral grassland to the wetland, and nests located in shrubs at different heights. We found 84% of nests failed, counting birds, mice, and armadillos as the main predators. Vegetation cover affected predation events of birds and small mammals, but not those of larger mammals. In turn, small mammals preyed on nests exclusively located in peripheral grassland, medium mammals preferred nests placed in open wetlands, and predation by birds was irrespective of open wetlands and grassland. We also found differences in nest predator assemblage between nests placed on the ground and in shrubs, with birds being the main predators of nests located above ground. These results can be attributed to differential habitat use and movement patterns specific to each predator group. Therefore, the identity, density, and behaviour of predators should be taken into account when planning conservation strategies for birds breeding in wetlands.
{"title":"Nest predation in Patagonian wetlands: predator assemblage and microhabitat characteristics","authors":"M. S. Vazquez, G. Amico","doi":"10.1080/01584197.2022.2153700","DOIUrl":"https://doi.org/10.1080/01584197.2022.2153700","url":null,"abstract":"ABSTRACT Multiple factors influence predation risk, ranging from habitat conditions to the composition and behaviour of predators. Although these factors are well documented for forest ecosystems, there is little evidence for wetlands, especially within Patagonia. Using artificial nests and camera traps, we documented the nest predation rates and predator assemblage of birds nesting in wetlands of the Patagonian steppe. We also determined the effect of vegetation cover on nest survival and studied the variation in predator groups according to nest placement: nests located in an open wetland, peripheral grassland to the wetland, and nests located in shrubs at different heights. We found 84% of nests failed, counting birds, mice, and armadillos as the main predators. Vegetation cover affected predation events of birds and small mammals, but not those of larger mammals. In turn, small mammals preyed on nests exclusively located in peripheral grassland, medium mammals preferred nests placed in open wetlands, and predation by birds was irrespective of open wetlands and grassland. We also found differences in nest predator assemblage between nests placed on the ground and in shrubs, with birds being the main predators of nests located above ground. These results can be attributed to differential habitat use and movement patterns specific to each predator group. Therefore, the identity, density, and behaviour of predators should be taken into account when planning conservation strategies for birds breeding in wetlands.","PeriodicalId":50532,"journal":{"name":"Emu-Austral Ornithology","volume":"32 1","pages":"24 - 34"},"PeriodicalIF":1.3,"publicationDate":"2023-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90554766","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}