Pub Date : 2023-01-01DOI: 10.1017/s0959270923000254
Tulsi R. Subedi, Juan M. Pérez-García, Sandesh Gurung, Hem S. Baral, Aishwarya Bhattacharjee, José D. Anadón, Munir Z. Virani, Simon Thomsett, Ralph Buij
Summary Raptors play a unique role in ecosystem services and are regarded as effective indicators of ecosystem health. In recent years, varieties of anthropogenic factors have threatened the majority of raptor species worldwide. Nepal is considered a global hotspot for threatened and declining raptor species, but there is limited information on the direct human threats to the raptor populations living in the country. In this paper, we identify important anthropogenic threats to raptors in Nepal based on raptor mortality data collected by powerline surveys and from monitoring of GPS-tagged raptors, complete various reports, and social media. We found that powerlines, poisoning, and persecution, mainly shooting, are significant threats to raptors in Nepal that were largely overlooked previously. We report 54 electrocuted raptors affecting eight species, 310 poisoned raptors of 11 species, and five persecuted raptors of four species; among them vultures are the most affected (>88%). Based on our findings, to safeguard the future of Nepal’s raptors, we propose the retrofitting of power poles and the use of flight diverters on powerlines in the most affected areas to reduce raptor interactions with powerlines, as well as an effective conservation education programme to prevent the use of unintentional poisoning.
{"title":"Human-induced mortality an overlooked threat for raptors in Nepal","authors":"Tulsi R. Subedi, Juan M. Pérez-García, Sandesh Gurung, Hem S. Baral, Aishwarya Bhattacharjee, José D. Anadón, Munir Z. Virani, Simon Thomsett, Ralph Buij","doi":"10.1017/s0959270923000254","DOIUrl":"https://doi.org/10.1017/s0959270923000254","url":null,"abstract":"Summary Raptors play a unique role in ecosystem services and are regarded as effective indicators of ecosystem health. In recent years, varieties of anthropogenic factors have threatened the majority of raptor species worldwide. Nepal is considered a global hotspot for threatened and declining raptor species, but there is limited information on the direct human threats to the raptor populations living in the country. In this paper, we identify important anthropogenic threats to raptors in Nepal based on raptor mortality data collected by powerline surveys and from monitoring of GPS-tagged raptors, complete various reports, and social media. We found that powerlines, poisoning, and persecution, mainly shooting, are significant threats to raptors in Nepal that were largely overlooked previously. We report 54 electrocuted raptors affecting eight species, 310 poisoned raptors of 11 species, and five persecuted raptors of four species; among them vultures are the most affected (>88%). Based on our findings, to safeguard the future of Nepal’s raptors, we propose the retrofitting of power poles and the use of flight diverters on powerlines in the most affected areas to reduce raptor interactions with powerlines, as well as an effective conservation education programme to prevent the use of unintentional poisoning.","PeriodicalId":9275,"journal":{"name":"Bird Conservation International","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135402141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-12DOI: 10.1017/S0959270922000399
David C. Hille, D. Wiedenfeld, M. Lezama-López, D. Brightsmith, M. Patten
Summary Monitoring parrot populations is of high importance because there is a general lack of quantified population trends for one of the most threatened avian orders. We surveyed parrots in Nicaragua in 1995, 1999, 2004, and 2013 at a minimum of 227 points within 56 sites stratified among the Pacific, Central Highlands, and Caribbean biogeographical regions to assess population trends. From point-count data we calculated encounter rate, flock rate, and flock size metrics and we used presence/absence data to generate species-specific occupancy estimates. Encounter rate, flock rate, and flock size data suggested family-level declines from 1995 to 2004 with some recovery between 2004 and 2013. Patterns of parrot occupancy varied among species with four decreasing, five increasing, and two with no detectable change. Six species of conservation concern are identified, including the Critically Endangered Great Green Macaw and Yellow-naped Parrot, additionally Olive-throated Parakeet, Scarlet Macaw, Brown-hooded Parrot, and White-crowned Parrot, only listed as Least Concern. All six are likely suffering from deforestation and potential unchecked trade activity in the Caribbean. Differing population trends of the regionally disjunct Yellow-naped Parrot subspecies suggest a link to variable deforestation and trade pressure experienced between the Pacific and Caribbean. Our results highlight the importance of actively monitoring changing parrot populations, even when considered Least Concern, so that directed conservation actions can be taken if needed.
{"title":"Parrot population trends in Nicaragua revealed by long-term monitoring","authors":"David C. Hille, D. Wiedenfeld, M. Lezama-López, D. Brightsmith, M. Patten","doi":"10.1017/S0959270922000399","DOIUrl":"https://doi.org/10.1017/S0959270922000399","url":null,"abstract":"Summary Monitoring parrot populations is of high importance because there is a general lack of quantified population trends for one of the most threatened avian orders. We surveyed parrots in Nicaragua in 1995, 1999, 2004, and 2013 at a minimum of 227 points within 56 sites stratified among the Pacific, Central Highlands, and Caribbean biogeographical regions to assess population trends. From point-count data we calculated encounter rate, flock rate, and flock size metrics and we used presence/absence data to generate species-specific occupancy estimates. Encounter rate, flock rate, and flock size data suggested family-level declines from 1995 to 2004 with some recovery between 2004 and 2013. Patterns of parrot occupancy varied among species with four decreasing, five increasing, and two with no detectable change. Six species of conservation concern are identified, including the Critically Endangered Great Green Macaw and Yellow-naped Parrot, additionally Olive-throated Parakeet, Scarlet Macaw, Brown-hooded Parrot, and White-crowned Parrot, only listed as Least Concern. All six are likely suffering from deforestation and potential unchecked trade activity in the Caribbean. Differing population trends of the regionally disjunct Yellow-naped Parrot subspecies suggest a link to variable deforestation and trade pressure experienced between the Pacific and Caribbean. Our results highlight the importance of actively monitoring changing parrot populations, even when considered Least Concern, so that directed conservation actions can be taken if needed.","PeriodicalId":9275,"journal":{"name":"Bird Conservation International","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2022-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44732543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-01DOI: 10.1017/S0959270922000417
L. Lopes, Ricardo C. de Meireles, H. Peixoto, J. P. Teixeira, T. L. D. S. S. Machado, V. Lombardi
Summary Understanding the types of movements exhibited by a threatened species is paramount for creating conservation and management strategies. The Campo Miner (Geositta poeciloptera) is a threatened obligate grassland bird endemic to the South American Cerrado. Literature disagrees about its movement ecology, with authors suggesting strategies as contradictory as residency and nomadism. The species requires short and sparse grass cover to breed and seems to be associated with fires, tracking recently burned grassland patches. We studied the movement ecology of marked Campo Miners for seven years, integrating our results with information from citizen science data, museum specimens, and the literature. After investigating every main movement strategy exhibited by bird populations, we found no evidence of regular migration in the species (e.g. altitudinal, short- or long-distance). The Campo Miner is a resident species with territorial behaviour restricted to the breeding season, which apparently results in seasonal variation in its detectability, biasing our perception about its seasonal abundance and distribution. We propose a theoretical framework for understanding local movements in the species, which predicts that Campo Miners: (1) establish their territories at the beginning of the breeding season in patches of suitable habitat; (2) stop defending their territories after the breeding season; (3) stay during the non-breeding season in their home ranges, also wandering across neighbouring home ranges; (4) abandon their home ranges if the grass cover becomes high and dense or when a better quality habitat patch becomes available, using fires as a cue for locating recently burned patches that will soon
{"title":"Movement ecology of the threatened Campo Miner Geositta poeciloptera and its implications for the conservation of tropical open grassland birds","authors":"L. Lopes, Ricardo C. de Meireles, H. Peixoto, J. P. Teixeira, T. L. D. S. S. Machado, V. Lombardi","doi":"10.1017/S0959270922000417","DOIUrl":"https://doi.org/10.1017/S0959270922000417","url":null,"abstract":"Summary Understanding the types of movements exhibited by a threatened species is paramount for creating conservation and management strategies. The Campo Miner (Geositta poeciloptera) is a threatened obligate grassland bird endemic to the South American Cerrado. Literature disagrees about its movement ecology, with authors suggesting strategies as contradictory as residency and nomadism. The species requires short and sparse grass cover to breed and seems to be associated with fires, tracking recently burned grassland patches. We studied the movement ecology of marked Campo Miners for seven years, integrating our results with information from citizen science data, museum specimens, and the literature. After investigating every main movement strategy exhibited by bird populations, we found no evidence of regular migration in the species (e.g. altitudinal, short- or long-distance). The Campo Miner is a resident species with territorial behaviour restricted to the breeding season, which apparently results in seasonal variation in its detectability, biasing our perception about its seasonal abundance and distribution. We propose a theoretical framework for understanding local movements in the species, which predicts that Campo Miners: (1) establish their territories at the beginning of the breeding season in patches of suitable habitat; (2) stop defending their territories after the breeding season; (3) stay during the non-breeding season in their home ranges, also wandering across neighbouring home ranges; (4) abandon their home ranges if the grass cover becomes high and dense or when a better quality habitat patch becomes available, using fires as a cue for locating recently burned patches that will soon","PeriodicalId":9275,"journal":{"name":"Bird Conservation International","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47651151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-21DOI: 10.1017/S0959270922000442
J. Fischer, S. Bose, Cynthia Romero, M. Charteris, P. Crowe, G. Parker, S. Ray, K. Rexer-Huber, P. Sagar, D. Thompson, Elizabeth A Bell, I. Debski, J. Quiñones
Summary Seabirds are highly threatened, including by fisheries bycatch. Accurate understanding of offshore distribution of seabirds is crucial to address this threat. Tracking technologies revolutionised insights into seabird distributions but tracking data may contain a variety of biases. We tracked two threatened seabirds (Salvin’s Albatross Thalassarche salvini n = 60 and Black Petrel Procellaria parkinsoni n = 46) from their breeding colonies in Aotearoa (New Zealand) to their non-breeding grounds in South America, including Peru, while simultaneously completing seven surveys in Peruvian waters. We then used species distribution models to predict occurrence and distribution using either data source alone, and both data sources combined. Results showed seasonal differences between estimates of occurrence and distribution when using data sources independently. Combining data resulted in more balanced insights into occurrence and distributions, and reduced uncertainty. Most notably, both species were predicted to occur in Peruvian waters during all four annual quarters: the northern Humboldt upwelling system for Salvin’s Albatross and northern continental shelf waters for Black Petrels. Our results highlighted that relying on a single data source may introduce biases into distribution estimates. Our tracking data might have contained ontological and/or colony-related biases (e.g. only breeding adults from one colony were tracked), while our survey data might have contained spatiotemporal biases (e.g. surveys were limited to waters <200 nm from the coast). We recommend combining data sources wherever possible to refine predictions of species distributions, which ultimately will improve fisheries bycatch management through better spatiotemporal understanding of risks.
海鸟受到包括渔获物在内的高度威胁。准确了解海鸟的近海分布对应对这一威胁至关重要。追踪技术彻底改变了人们对海鸟分布的认识，但追踪数据可能包含各种偏差。我们跟踪了两种濒临灭绝的海鸟(salin 's Albatross Thalassarche salvini n = 60)和黑海燕(Black petraria parkinsoni n = 46)，从它们在新西兰奥特罗阿(Aotearoa)的繁殖地到南美洲(包括秘鲁)的非繁殖地，同时在秘鲁水域完成了7项调查。然后，我们使用物种分布模型来预测发生和分布，其中一个数据源单独使用，两个数据源结合使用。结果显示，当独立使用数据源时，估计的发生和分布之间存在季节性差异。结合数据可以更平衡地了解发生和分布情况，并减少不确定性。最值得注意的是，这两种物种都被预测在秘鲁水域全年四个季度都有出现:洪堡北部上升流系统中有信天翁，北部大陆架水域中有黑海燕。我们的结果强调，依赖单一数据源可能会在分布估计中引入偏差。我们的跟踪数据可能包含本体学和/或群体相关的偏差(例如，只跟踪了一个群体的繁殖成虫)，而我们的调查数据可能包含时空偏差(例如，调查仅限于距离海岸<200海里的水域)。我们建议尽可能结合数据来源，以完善物种分布的预测，最终通过更好地了解风险的时空，改善渔业副渔获物管理。
{"title":"Combining tracking with at-sea surveys to improve occurrence and distribution estimates of two threatened seabirds in Peru","authors":"J. Fischer, S. Bose, Cynthia Romero, M. Charteris, P. Crowe, G. Parker, S. Ray, K. Rexer-Huber, P. Sagar, D. Thompson, Elizabeth A Bell, I. Debski, J. Quiñones","doi":"10.1017/S0959270922000442","DOIUrl":"https://doi.org/10.1017/S0959270922000442","url":null,"abstract":"Summary Seabirds are highly threatened, including by fisheries bycatch. Accurate understanding of offshore distribution of seabirds is crucial to address this threat. Tracking technologies revolutionised insights into seabird distributions but tracking data may contain a variety of biases. We tracked two threatened seabirds (Salvin’s Albatross Thalassarche salvini n = 60 and Black Petrel Procellaria parkinsoni n = 46) from their breeding colonies in Aotearoa (New Zealand) to their non-breeding grounds in South America, including Peru, while simultaneously completing seven surveys in Peruvian waters. We then used species distribution models to predict occurrence and distribution using either data source alone, and both data sources combined. Results showed seasonal differences between estimates of occurrence and distribution when using data sources independently. Combining data resulted in more balanced insights into occurrence and distributions, and reduced uncertainty. Most notably, both species were predicted to occur in Peruvian waters during all four annual quarters: the northern Humboldt upwelling system for Salvin’s Albatross and northern continental shelf waters for Black Petrels. Our results highlighted that relying on a single data source may introduce biases into distribution estimates. Our tracking data might have contained ontological and/or colony-related biases (e.g. only breeding adults from one colony were tracked), while our survey data might have contained spatiotemporal biases (e.g. surveys were limited to waters <200 nm from the coast). We recommend combining data sources wherever possible to refine predictions of species distributions, which ultimately will improve fisheries bycatch management through better spatiotemporal understanding of risks.","PeriodicalId":9275,"journal":{"name":"Bird Conservation International","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2022-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44504850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-15DOI: 10.1017/S0959270922000430
Eva Serrano-Davies, J. Traba, B. Arroyo, F. Mougeot, Francesc Cuscó, S. Mañosa, G. Bota, N. Faria, A. Villers, F. Casas, C. Attié, Pierrick Devoucoux, V. Bretagnolle, M. Morales
Summary Adult sex ratios (ASRs) have proved to correlate with population trends, which make them potential useful indicators of a species’ population trajectory and conservation status. We analysed ASRs and proportion of juveniles in flocks of an endangered steppe bird, the Little Bustard Tetrax tetrax, using surveys made during the non-breeding period in seven areas within its Western European range (one in Portugal, four in Spain, and two in France). We found overall male-biased ASRs, as all the seven surveyed areas showed a male-biased ASR mean value. Five areas were below the threshold median value (female sex ratio = 0.4) considered to be consistent with an increased probability of extinction, according to earlier population viability analyses for the species. We also found a significant positive correlation between female ratio and the proportion of young individuals in the non-breeding flocks surveyed. Our results (strongly male-biased ASRs) support the hypothesis that the viability of Little Bustard populations in Western Europe is threatened by an excess of female mortality, something that should be quantified in the future, and emphasise the value of monitoring sex ratio as a population viability indicator in species where monitoring survival is difficult to achieve.
{"title":"Biased adult sex ratios in Western Europe populations of Little Bustard Tetrax tetrax as a potential warning signal of unbalanced mortalities","authors":"Eva Serrano-Davies, J. Traba, B. Arroyo, F. Mougeot, Francesc Cuscó, S. Mañosa, G. Bota, N. Faria, A. Villers, F. Casas, C. Attié, Pierrick Devoucoux, V. Bretagnolle, M. Morales","doi":"10.1017/S0959270922000430","DOIUrl":"https://doi.org/10.1017/S0959270922000430","url":null,"abstract":"Summary Adult sex ratios (ASRs) have proved to correlate with population trends, which make them potential useful indicators of a species’ population trajectory and conservation status. We analysed ASRs and proportion of juveniles in flocks of an endangered steppe bird, the Little Bustard Tetrax tetrax, using surveys made during the non-breeding period in seven areas within its Western European range (one in Portugal, four in Spain, and two in France). We found overall male-biased ASRs, as all the seven surveyed areas showed a male-biased ASR mean value. Five areas were below the threshold median value (female sex ratio = 0.4) considered to be consistent with an increased probability of extinction, according to earlier population viability analyses for the species. We also found a significant positive correlation between female ratio and the proportion of young individuals in the non-breeding flocks surveyed. Our results (strongly male-biased ASRs) support the hypothesis that the viability of Little Bustard populations in Western Europe is threatened by an excess of female mortality, something that should be quantified in the future, and emphasise the value of monitoring sex ratio as a population viability indicator in species where monitoring survival is difficult to achieve.","PeriodicalId":9275,"journal":{"name":"Bird Conservation International","volume":"33 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2022-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41649714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-31DOI: 10.1017/s0959270922000429
Bárbara Freitas, M. Melo, Ceciliano do Bom Jesus, Sátiro R. da Costa, Yodiney dos Santos, A. Crottini, R. D. de Lima
Species baseline information is required for effective biodiversity conservation. Here we provide sound ecological data to support effective conservation of the Principe Scops-owl, Otusbikegila Melo, Freitas, Verbelen, Costa, Pereira, Fuchs, Sangster, Correia, de Lima & Crottini 2022, discovered in 2016. We mapped the observed and potential distribution, inferred habitat associations, estimated population size, and assessed the International Union for Conservation of Nature (IUCN) Red List category for this species. Surveys were carried out across Príncipe Island during the long and short dry seasons, recording owl presence in sampling points along transects. These data were used to model distribution, revealing that the Principe Scops-owl is restricted to 34.4 km2 in the south of the island, inside the Príncipe Obô Natural Park. Most records were in lower altitude native forest. Remoteness was the most important variable to explain presence at island level, followed by land use, which showed that the species is restricted to forest, clearly depending on native forest. Distance sampling using different models suggested a population density ranging between 33.4 individuals/km2 (95% CI: 23.6–47.2) and 46.4 individuals/km2 (95% CI: 29.3–73.6), which extrapolates to an estimated population size ranging from 1,149 individuals (95% CI: 813–1,623) to 1,597 individuals (95% CI: 1,007–2,533). We propose that the species is classified as “Critically Endangered” due to the small extent of occurrence, coupled with occurrence in a single location and inferred continuing declines in the extent of occurrence, area of occupancy, number of mature individuals and area, extent, and quality of habitat. Effective conservation of the Principe Scops-owl requires regular monitoring and further studies focusing on reproduction and potential nest predation by introduced mammals. Widespread support for the conservation of the Natural Park is vital to ensure the protection of this species and the endemic-rich native forests of Príncipe on which it depends.
{"title":"The recently discovered Principe Scops-owl is highly threatened: distribution, habitat associations, and population estimates","authors":"Bárbara Freitas, M. Melo, Ceciliano do Bom Jesus, Sátiro R. da Costa, Yodiney dos Santos, A. Crottini, R. D. de Lima","doi":"10.1017/s0959270922000429","DOIUrl":"https://doi.org/10.1017/s0959270922000429","url":null,"abstract":"\u0000 Species baseline information is required for effective biodiversity conservation. Here we provide sound ecological data to support effective conservation of the Principe Scops-owl, Otusbikegila Melo, Freitas, Verbelen, Costa, Pereira, Fuchs, Sangster, Correia, de Lima & Crottini 2022, discovered in 2016. We mapped the observed and potential distribution, inferred habitat associations, estimated population size, and assessed the International Union for Conservation of Nature (IUCN) Red List category for this species. Surveys were carried out across Príncipe Island during the long and short dry seasons, recording owl presence in sampling points along transects. These data were used to model distribution, revealing that the Principe Scops-owl is restricted to 34.4 km2 in the south of the island, inside the Príncipe Obô Natural Park. Most records were in lower altitude native forest. Remoteness was the most important variable to explain presence at island level, followed by land use, which showed that the species is restricted to forest, clearly depending on native forest. Distance sampling using different models suggested a population density ranging between 33.4 individuals/km2 (95% CI: 23.6–47.2) and 46.4 individuals/km2 (95% CI: 29.3–73.6), which extrapolates to an estimated population size ranging from 1,149 individuals (95% CI: 813–1,623) to 1,597 individuals (95% CI: 1,007–2,533). We propose that the species is classified as “Critically Endangered” due to the small extent of occurrence, coupled with occurrence in a single location and inferred continuing declines in the extent of occurrence, area of occupancy, number of mature individuals and area, extent, and quality of habitat. Effective conservation of the Principe Scops-owl requires regular monitoring and further studies focusing on reproduction and potential nest predation by introduced mammals. Widespread support for the conservation of the Natural Park is vital to ensure the protection of this species and the endemic-rich native forests of Príncipe on which it depends.","PeriodicalId":9275,"journal":{"name":"Bird Conservation International","volume":"1 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2022-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46741448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-27DOI: 10.1017/S0959270922000387
A. Raine, S. Driskill, Jennnifer Rothe, M. Travers
Summary The ‘a‘o, or Newell’s Shearwater Puffinus newelli, is an endangered shearwater species endemic to the Hawaiian Islands, with 90% of the world population found on Kaua‘i. Understanding the breeding phenology of the species is vital for identifying key periods for colony management actions and the timing and exposure frequency to infrastructure threats such as powerline collisions and light attraction. We used a combination of direct burrow monitoring and remote cameras at multiple colonies between 2012 and 2019 for a detailed assessment of the breeding phenology for this species. Breeding adults started arriving at the burrow in mid-April, some (but not all) underwent a two-week exodus in May and returned at the end of May to commence incubation. Incubation continued until mid-July. The chick-rearing period ran until the end of September. Fledging peaked in October with the last birds fledging towards the middle of November. Breeding was not synchronised, with a 59-day gap between the first and last fledging birds. The importance of this information to management actions is discussed, particularly in terms of directing management actions to key periods of vulnerability to introduced predators (such as peak incubation, chick emergence, and exercising prior to fledging), the precise timing of fledgling fallout related to light attraction, and directing colony-monitoring actions and translocation projects. We also consider the utility of the data in assessing species composition of powerline collisions and collision risk. Future work using acoustic monitoring is recommended for assessing the phenology of non-breeders and prospectors at colonies.
{"title":"Evaluating the breeding phenology of the endangered ‘a‘o (Newell’s Shearwater Puffinus newelli) on Kaua‘i to better focus conservation actions and management decisions","authors":"A. Raine, S. Driskill, Jennnifer Rothe, M. Travers","doi":"10.1017/S0959270922000387","DOIUrl":"https://doi.org/10.1017/S0959270922000387","url":null,"abstract":"Summary The ‘a‘o, or Newell’s Shearwater Puffinus newelli, is an endangered shearwater species endemic to the Hawaiian Islands, with 90% of the world population found on Kaua‘i. Understanding the breeding phenology of the species is vital for identifying key periods for colony management actions and the timing and exposure frequency to infrastructure threats such as powerline collisions and light attraction. We used a combination of direct burrow monitoring and remote cameras at multiple colonies between 2012 and 2019 for a detailed assessment of the breeding phenology for this species. Breeding adults started arriving at the burrow in mid-April, some (but not all) underwent a two-week exodus in May and returned at the end of May to commence incubation. Incubation continued until mid-July. The chick-rearing period ran until the end of September. Fledging peaked in October with the last birds fledging towards the middle of November. Breeding was not synchronised, with a 59-day gap between the first and last fledging birds. The importance of this information to management actions is discussed, particularly in terms of directing management actions to key periods of vulnerability to introduced predators (such as peak incubation, chick emergence, and exercising prior to fledging), the precise timing of fledgling fallout related to light attraction, and directing colony-monitoring actions and translocation projects. We also consider the utility of the data in assessing species composition of powerline collisions and collision risk. Future work using acoustic monitoring is recommended for assessing the phenology of non-breeders and prospectors at colonies.","PeriodicalId":9275,"journal":{"name":"Bird Conservation International","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2022-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49616036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-03DOI: 10.1017/S095927092200034X
Lisa J. Paguntalan, Andrew R. T. Reintar, Godfrey C. Jakosalem, Gabrielle Peña, Alona Villarojo
Summary The Endangered Black Shama Kittacincla cebuensis is endemic to the island of Cebu, Philippines. We surveyed 11 forest patches from February 2018 to March 2020 to determine current distribution, habitat requirements, and population density of the Black Shama. A total of 111 point count stations was surveyed resulting in 93 Black Shama detections. Using point count Distance sampling, the population density was estimated at 313 individuals/km2 for a total population of 11,839 individuals (9,160–15,415). The largest sub-population (10,470) was in Alcoy, followed by Argao (711), and Dalaguete (325). Our total population estimate and sub-population estimates were higher than the estimate of 6,650 individuals made by BirdLife International for the International Union for the Conservation of Nature. The species was found to survive in a variety of habitats in at least 20 localities covering roughly 37 km2 of karst forest. We did not encounter the bird in seven areas of its former range. Protection of the remaining forests of Cebu and the establishment of plantations of native tree species in between forest patches are crucial to the survival of the species.
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