Aritri Sarkar, S. S. Sailas, S. Babu, P. Karunakaran, H. N. Kumara, Sureshmarimuthu Shanmugavel, Padmanaban Pramod
Abstract. Community Reserves, which are Community Conserved Areas, form the majority of the Protected Area Network in northeast India. Because this biodiverse region is threatened by a variety of anthropogenic activities, Community Reserves likely serve as refugia sites for stenotopic, cavity-nesting species such as some owls. To test this hypothesis, we conducted nocturnal surveys in 11 Community Reserves comprised of primary or secondary forest and outside Community Reserves in Meghalaya state, northeast India. We then used nonparametric tests to assess differences in the occurrence of owls among these three categories. We found that on average, occurrence of owls was higher inside Community Reserves. Inside Community Reserves with secondary forests, we found significantly higher occurrence of the Asian Barred Owlet (Glaucidium cuculoides) and Collared Scops-Owl (Otus lettia), while in Community Reserves with primary forest, we found significantly higher occurrence of the Brown Wood-Owl (Strix leptogrammica), a declining old-growth forest specialist. Hence, Community Reserves are serving as sites of refugia for owls in northeast India. However, anthropogenic pressures such as logging, shifting cultivation, and developmental activities threaten the forests of the region. Old-growth forests are also scarce in Meghalaya and were present in only two of the Community Reserves. Therefore, we find it of prime importance to conserve these reserves, especially those containing primary forests, and to allocate more areas as Community Reserves in the region. Resumen. Las Reservas Comunitarias son Áreas Conservadas por las Comunidades locales y constituyen la mayor parte de la Red de Áreas Protegidas en el noreste de India. Debido a que esta región biodiversa está amenazada por una variedad de actividades antropogénicas, las Reservas Comunitarias probablemente sirvan como sitios de refugio para especies estenotópicas que anidan en cavidades, como algunos búhos. Para probar esta hipótesis, realizamos censos nocturnos en 11 Reservas Comunitarias compuestas por bosques primarios o secundarios, y fuera de las Reservas Comunitarias, en el estado de Meghalaya, al noreste de India. Utilizamos pruebas no paramétricas para evaluar las diferencias en la presencia de búhos entre estas tres categorías. Encontramos que, en promedio, la presencia de búhos era mayor dentro de las Reservas Comunitarias. Dentro de las Reservas Comunitarias con bosques secundarios, encontramos una presencia significativamente mayor de Glaucidium cuculoides y Otus lettia, mientras que en las Reservas Comunitarias con bosque primario encontramos una presencia significativamente mayor de Strix leptogrammica, un especialista de bosques maduros en declive. Por lo tanto, las Reservas Comunitarias están sirviendo como sitios de refugio para los búhos en el noreste de India. Sin embargo, las presiones antropogénicas como la tala, el cambio en los cultivos y las actividades de desarrollo amenazan lo
摘要社区保护区，即社区保护区，构成了印度东北部保护区网络的大部分。由于这一生物多样性地区受到各种人为活动的威胁，社区保护区可能成为一些狭窄、洞穴筑巢物种(如猫头鹰)的避难所。为了验证这一假设，我们在印度东北部梅加拉亚邦的11个由原生林或次生林组成的社区保护区和社区保护区外进行了夜间调查。然后，我们使用非参数测试来评估这三类猫头鹰发生的差异。我们发现，平均而言，猫头鹰在社区保护区的发生率更高。在有次生林的社区保护区内，我们发现亚洲斑Owlet (Glaucidium cuculoides)和颈颈鸮(Otus lettia)的发生率显著较高，而在有原生林的社区保护区内，我们发现褐木鸮(Strix leptogrammica)的发生率显著较高。因此，社区保护区在印度东北部成为猫头鹰的避难所。然而，人为的压力，如伐木、转移耕作和开发活动，威胁着该地区的森林。梅加拉亚邦的原始森林也很稀少，只有两个社区保护区有原始森林。因此，我们认为保护这些保护区，特别是含有原始森林的保护区，并在该地区分配更多的区域作为社区保护区是至关重要的。Resumen。Las Reservas communitarias son Áreas Conservadas poror Las communidades locales y constituyen la mayor partite de la Red de Áreas Protegidas en el noreste de India。Debido a que esta región生物多样性评估和人类个体的各种活动，如保留地社区，可能的情况，如难民的情况estenotópicas和生物多样性评估，como algunos búhos。Para probar esta hipótesis，实现11个共产主义保留地的人口普查，包括初级和次级的人口普查，以及所有共产主义保留地的人口普查，包括梅加拉亚邦州的人口普查，印度的人口普查。在现有的búhos资料中心和数据中心categorías资料中心中，利用pruza和pruza之间的差别。在社区保留区市长的领导下，在临时会议上通过了búhos。社区保留区与第二地区的人口普查结果一致，社区保留区与第一地区的人口普查结果一致，社区保留区与第二地区的人口普查结果一致，社区保留区与第一地区的人口普查结果一致，社区保留区的人口普查结果一致，社区保留区的人口普查结果一致。穷人穷人穷人穷人穷人穷人穷人穷人穷人穷人穷人穷人穷人穷人穷人穷人穷人búhos穷人穷人穷人。罪禁运,拉斯维加斯人antropogenicas科莫la塔拉,埃尔卡:在洛杉矶cultivos y拉斯维加斯对于de desarrollo amenazan洛杉矶博斯克de la地区。在梅加拉亚邦，有两名男子在梅加拉亚邦的私人住宅里居住。可怜的tanto，没有足够的资源来保护自然保护区，特别是原始大陆的水生动物，通过指定más áreas comcomreservas commununarias en la región。[Traducción del equipo社论]
{"title":"Community Reserves Serve as Refugia Sites for Cavity-Nesting Owls in Northeast India","authors":"Aritri Sarkar, S. S. Sailas, S. Babu, P. Karunakaran, H. N. Kumara, Sureshmarimuthu Shanmugavel, Padmanaban Pramod","doi":"10.3356/JRR-21-48","DOIUrl":"https://doi.org/10.3356/JRR-21-48","url":null,"abstract":"Abstract. Community Reserves, which are Community Conserved Areas, form the majority of the Protected Area Network in northeast India. Because this biodiverse region is threatened by a variety of anthropogenic activities, Community Reserves likely serve as refugia sites for stenotopic, cavity-nesting species such as some owls. To test this hypothesis, we conducted nocturnal surveys in 11 Community Reserves comprised of primary or secondary forest and outside Community Reserves in Meghalaya state, northeast India. We then used nonparametric tests to assess differences in the occurrence of owls among these three categories. We found that on average, occurrence of owls was higher inside Community Reserves. Inside Community Reserves with secondary forests, we found significantly higher occurrence of the Asian Barred Owlet (Glaucidium cuculoides) and Collared Scops-Owl (Otus lettia), while in Community Reserves with primary forest, we found significantly higher occurrence of the Brown Wood-Owl (Strix leptogrammica), a declining old-growth forest specialist. Hence, Community Reserves are serving as sites of refugia for owls in northeast India. However, anthropogenic pressures such as logging, shifting cultivation, and developmental activities threaten the forests of the region. Old-growth forests are also scarce in Meghalaya and were present in only two of the Community Reserves. Therefore, we find it of prime importance to conserve these reserves, especially those containing primary forests, and to allocate more areas as Community Reserves in the region. Resumen. Las Reservas Comunitarias son Áreas Conservadas por las Comunidades locales y constituyen la mayor parte de la Red de Áreas Protegidas en el noreste de India. Debido a que esta región biodiversa está amenazada por una variedad de actividades antropogénicas, las Reservas Comunitarias probablemente sirvan como sitios de refugio para especies estenotópicas que anidan en cavidades, como algunos búhos. Para probar esta hipótesis, realizamos censos nocturnos en 11 Reservas Comunitarias compuestas por bosques primarios o secundarios, y fuera de las Reservas Comunitarias, en el estado de Meghalaya, al noreste de India. Utilizamos pruebas no paramétricas para evaluar las diferencias en la presencia de búhos entre estas tres categorías. Encontramos que, en promedio, la presencia de búhos era mayor dentro de las Reservas Comunitarias. Dentro de las Reservas Comunitarias con bosques secundarios, encontramos una presencia significativamente mayor de Glaucidium cuculoides y Otus lettia, mientras que en las Reservas Comunitarias con bosque primario encontramos una presencia significativamente mayor de Strix leptogrammica, un especialista de bosques maduros en declive. Por lo tanto, las Reservas Comunitarias están sirviendo como sitios de refugio para los búhos en el noreste de India. Sin embargo, las presiones antropogénicas como la tala, el cambio en los cultivos y las actividades de desarrollo amenazan lo","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"1 1","pages":"22 - 29"},"PeriodicalIF":1.7,"publicationDate":"2022-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75378075","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}
E. Buechley, D. Oleyar, Jesse L. Watson, Jennifer Bridgeman, S. Volker, D. A. Goldade, C. Swift, B. Rattner
Although there is extensive evidence of declines in the American Kestrel (Falco sparverius) population across North America, the cause of such declines remains a mystery. One hypothesized driver of decline is anticoagulant rodenticide (AR) exposure, which could potentially cause mortality or reduced fitness. We investigated AR exposure in wild American Kestrels in Utah, USA. We collected and tested for AR residues in liver samples (n = 8) from kestrels opportunistically encountered dead and in blood samples (n = 71) from live wild kestrels, both nestlings and adults. We found high detection rates in both tissues. Adult kestrels were more likely to exhibit exposure than juveniles sampled in nests. Three-quarters (six of eight) of tested liver samples from adult kestrels exhibited evidence of AR exposure. Additionally, liver samples (n = 19) opportunistically collected from seven species of raptors within our study area had detectable levels of AR residues, with seven of eight raptor species evidencing exposure; across all raptors, five ARs were detected in liver samples, with brodifacoum the most prevalent, being found in over half (14 of 27) of samples. Over half (7 of 12) of the blood samples from adult kestrels had detectible levels of ARs, while only one of 59 juvenile nest samples tested positive. The difference in exposure rates between adults and juveniles could indicate differential exposure pathways by age class. Based on these findings, we recommend that ARs be further investigated as a potential cause of kestrel declines. Future research could focus on expanding sampling to provide sufficient sample sizes to test for potential nonlethal effects of AR exposure (e.g., fecundity, nesting success), identifying potential exposure pathways, and developing methods for passive sampling of ARs in excreta.
{"title":"Preliminary Evidence of Anticoagulant Rodenticide Exposure in American Kestrels (Falco sparverius) in the Western United States","authors":"E. Buechley, D. Oleyar, Jesse L. Watson, Jennifer Bridgeman, S. Volker, D. A. Goldade, C. Swift, B. Rattner","doi":"10.3356/jrr-22-18","DOIUrl":"https://doi.org/10.3356/jrr-22-18","url":null,"abstract":"\u0000 Although there is extensive evidence of declines in the American Kestrel (Falco sparverius) population across North America, the cause of such declines remains a mystery. One hypothesized driver of decline is anticoagulant rodenticide (AR) exposure, which could potentially cause mortality or reduced fitness. We investigated AR exposure in wild American Kestrels in Utah, USA. We collected and tested for AR residues in liver samples (n = 8) from kestrels opportunistically encountered dead and in blood samples (n = 71) from live wild kestrels, both nestlings and adults. We found high detection rates in both tissues. Adult kestrels were more likely to exhibit exposure than juveniles sampled in nests. Three-quarters (six of eight) of tested liver samples from adult kestrels exhibited evidence of AR exposure. Additionally, liver samples (n = 19) opportunistically collected from seven species of raptors within our study area had detectable levels of AR residues, with seven of eight raptor species evidencing exposure; across all raptors, five ARs were detected in liver samples, with brodifacoum the most prevalent, being found in over half (14 of 27) of samples. Over half (7 of 12) of the blood samples from adult kestrels had detectible levels of ARs, while only one of 59 juvenile nest samples tested positive. The difference in exposure rates between adults and juveniles could indicate differential exposure pathways by age class. Based on these findings, we recommend that ARs be further investigated as a potential cause of kestrel declines. Future research could focus on expanding sampling to provide sufficient sample sizes to test for potential nonlethal effects of AR exposure (e.g., fecundity, nesting success), identifying potential exposure pathways, and developing methods for passive sampling of ARs in excreta.","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"52 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2022-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76916376","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}
Age-related differences in reproductive or breeding success, as measured by clutch size, hatching rate, nestling survival, and number of fledglings produced, have been well documented in many species of birds. The experience gained through successive breeding attempts can improve foraging abilities, survival skills, access to resources through social dominance, and familiarity with each stage of reproduction. We examined 696 breeding attempts by American Kestrels (Falco sparverius) from a population that bred in nest boxes in northwestern New Jersey from 1995 to 2021. We tested the hypothesis that older kestrels have greater breeding success than those in their first breeding season. Clutch size, nestling survival rate, and the number of fledglings varied significantly and positively with the age of one or both parents. These trends were significantly correlated with the date of clutch initiation; older birds initiated clutches earlier than those in their first breeding attempt. However, after we controlled for laying date, older birds still had larger clutch sizes, higher nestling survival rates, and greater numbers of fledglings. The relationship between age and breeding success was more pronounced for males than females. This difference is consistent with the behavioral roles of each sex during a breeding attempt. After laying a clutch, females perform most of the incubation and brood young nestlings. In contrast, males provide food for females prior to egg laying and throughout incubation, and to the entire family until the nestlings no longer are brooded by the female. Females paired with older males had significantly greater body mass index values (weight/wing chord) than those paired with second-year males. Pairs where both adults were older had significantly greater breeding success than mixed or young pairs, and we never observed an older female paired to a male during his first breeding attempt.
{"title":"Reproductive Success Increases with Age in American Kestrels, Especially in Males","authors":"Emilie R. Snyder, John A. Smallwood","doi":"10.3356/jrr-22-15","DOIUrl":"https://doi.org/10.3356/jrr-22-15","url":null,"abstract":"\u0000 Age-related differences in reproductive or breeding success, as measured by clutch size, hatching rate, nestling survival, and number of fledglings produced, have been well documented in many species of birds. The experience gained through successive breeding attempts can improve foraging abilities, survival skills, access to resources through social dominance, and familiarity with each stage of reproduction. We examined 696 breeding attempts by American Kestrels (Falco sparverius) from a population that bred in nest boxes in northwestern New Jersey from 1995 to 2021. We tested the hypothesis that older kestrels have greater breeding success than those in their first breeding season. Clutch size, nestling survival rate, and the number of fledglings varied significantly and positively with the age of one or both parents. These trends were significantly correlated with the date of clutch initiation; older birds initiated clutches earlier than those in their first breeding attempt. However, after we controlled for laying date, older birds still had larger clutch sizes, higher nestling survival rates, and greater numbers of fledglings. The relationship between age and breeding success was more pronounced for males than females. This difference is consistent with the behavioral roles of each sex during a breeding attempt. After laying a clutch, females perform most of the incubation and brood young nestlings. In contrast, males provide food for females prior to egg laying and throughout incubation, and to the entire family until the nestlings no longer are brooded by the female. Females paired with older males had significantly greater body mass index values (weight/wing chord) than those paired with second-year males. Pairs where both adults were older had significantly greater breeding success than mixed or young pairs, and we never observed an older female paired to a male during his first breeding attempt.","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"07 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2022-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86083215","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}
The American Kestrel (Falco sparverius), a small, cavity-nesting falcon that breeds across most of North America, is experiencing an apparent population decline across much of the United States that has yet to be sufficiently explained. With landscape change as a potential factor, the association of landscape composition with kestrel reproduction may assist not only in managing declines but also in improving the effectiveness and efficiency of nest box programs, which can bolster local populations and support monitoring and research efforts. We monitored 163 unique American Kestrel nest boxes over a 12-yr study period (2008–2019) in western Virginia to investigate the factors influencing kestrel reproductive success and we documented relatively high rates of both box occupancy (80%) and nest success (78.9%). In a study area dominated by both high- and low-intensity agriculture, we focused on identifying patterns in land cover composition that may limit reproductive success and associated each box with land cover composition metrics at four spatial scales. Generalized linear mixed models indicated nest boxes with a lower proportion of developed land within 500 m, and a higher proportion of crops and pasture/hay within 3 km were more likely to be occupied by kestrels. Although probability of kestrel nest success increased with reduced proportions of developed land within 100 m, the primary factors influencing success were clutch initiation date and the presence of European starlings (Sturnus vulgaris), with earlier nesting and the absence of starling activity resulting in higher nest success. Overall, cover-type associations with nest success and box occupancy were not strong and establishment of nest boxes in targeted kestrel habitat, while likely maximizing reproductive output, limits research opportunities to identify critical land cover thresholds for the species.
{"title":"Factors Associated with American Kestrel (Falco sparverius) Nest Box Occupancy and Reproductive Success in an Agricultural Landscape","authors":"J. Kolowski, L. Morrow, Jill Morrow","doi":"10.3356/jrr-21-64","DOIUrl":"https://doi.org/10.3356/jrr-21-64","url":null,"abstract":"\u0000 The American Kestrel (Falco sparverius), a small, cavity-nesting falcon that breeds across most of North America, is experiencing an apparent population decline across much of the United States that has yet to be sufficiently explained. With landscape change as a potential factor, the association of landscape composition with kestrel reproduction may assist not only in managing declines but also in improving the effectiveness and efficiency of nest box programs, which can bolster local populations and support monitoring and research efforts. We monitored 163 unique American Kestrel nest boxes over a 12-yr study period (2008–2019) in western Virginia to investigate the factors influencing kestrel reproductive success and we documented relatively high rates of both box occupancy (80%) and nest success (78.9%). In a study area dominated by both high- and low-intensity agriculture, we focused on identifying patterns in land cover composition that may limit reproductive success and associated each box with land cover composition metrics at four spatial scales. Generalized linear mixed models indicated nest boxes with a lower proportion of developed land within 500 m, and a higher proportion of crops and pasture/hay within 3 km were more likely to be occupied by kestrels. Although probability of kestrel nest success increased with reduced proportions of developed land within 100 m, the primary factors influencing success were clutch initiation date and the presence of European starlings (Sturnus vulgaris), with earlier nesting and the absence of starling activity resulting in higher nest success. Overall, cover-type associations with nest success and box occupancy were not strong and establishment of nest boxes in targeted kestrel habitat, while likely maximizing reproductive output, limits research opportunities to identify critical land cover thresholds for the species.","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"24 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2022-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73526044","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}
Abstract. The tail feathers of female American Kestrels (Falco sparverius) are rufous-brown with black bands down the entire length. There is considerable individual variation in the width and shape of these bands. The width of the most distal (subterminal) black band relative to the width of the next proximal black band may change with age. Published empirical data show that juvenal rectrices have either narrow or, less commonly, wide subterminal bands while adult rectrices consistently have wide subterminal bands. Here we review the literature about this characteristic and discuss how it has been used, and potentially misused, to age female American Kestrels. Resumen. Las plumas de la cola de las hembras de Falco sparverius son de color marrón rojizo con bandas negras en toda su longitud. Existe una variación individual considerable en el ancho y la forma de estas bandas. El ancho de la banda negra más distal (subterminal) en relación con el ancho de la siguiente banda negra proximal puede cambiar con la edad. Los datos empíricos publicados muestran que las rectrices de los juveniles tienen bandas subterminales estrechas o, con menos frecuencia, anchas, mientras que las rectrices de los adultos tienen, de forma consistente, bandas subterminales anchas. Aquí revisamos la literatura sobre esta característica y discutimos cómo ha sido utilizada, y potencialmente mal utilizada, para determinar la edad de las hembras de F. sparverius. [Traducción del equipo editorial]
摘要雌性美洲红隼(Falco sparverius)的尾羽是紫褐色的，整个长度上都有黑色的带。这些波段的宽度和形状有相当大的个体差异。最远端(近端)黑带的宽度相对于下一个近端黑带的宽度可能随年龄而变化。已发表的经验数据表明，幼鱼的履历要么窄，要么不太常见，宽的下顶带，而成年履历一直有宽的下顶带。在这里，我们回顾了关于这一特征的文献，并讨论了它是如何被使用的，以及潜在的误用，以使雌性美国红隼变老。Resumen。Las plumas de la cola de Las Las hembras de Falco sparverius son de color marrón rojizo con bandas negras en toda su longitude。存在一个variación个人相当大的规模，以固定的形式存在。El ancho de la banda negra más远端(亚终端)en relación con El ancho de la siguiente banda negra近端(cambiar con edad)。Los datos empíricos publicados muestran que las rectrices de Los juvenile tienen bandas subterminales estrechas, conmenos freuucia, anchas, mientras que las rectrices de Los adult tienen, de forma consistente, bandas subterminales anchas。Aquí对文献进行了修正，全文如下característica y discutimmos cómo，即“利用”，“潜在的利用”，para determinar la edad de las hembras de F. sparverius。[Traducción del equipo社论]
{"title":"The Use, and Misuse, of the Subterminal Black Tail Band to Age Female American Kestrels","authors":"John A. Smallwood, T. Ely, Carole E. Hallett","doi":"10.3356/JRR-22-45","DOIUrl":"https://doi.org/10.3356/JRR-22-45","url":null,"abstract":"Abstract. The tail feathers of female American Kestrels (Falco sparverius) are rufous-brown with black bands down the entire length. There is considerable individual variation in the width and shape of these bands. The width of the most distal (subterminal) black band relative to the width of the next proximal black band may change with age. Published empirical data show that juvenal rectrices have either narrow or, less commonly, wide subterminal bands while adult rectrices consistently have wide subterminal bands. Here we review the literature about this characteristic and discuss how it has been used, and potentially misused, to age female American Kestrels. Resumen. Las plumas de la cola de las hembras de Falco sparverius son de color marrón rojizo con bandas negras en toda su longitud. Existe una variación individual considerable en el ancho y la forma de estas bandas. El ancho de la banda negra más distal (subterminal) en relación con el ancho de la siguiente banda negra proximal puede cambiar con la edad. Los datos empíricos publicados muestran que las rectrices de los juveniles tienen bandas subterminales estrechas o, con menos frecuencia, anchas, mientras que las rectrices de los adultos tienen, de forma consistente, bandas subterminales anchas. Aquí revisamos la literatura sobre esta característica y discutimos cómo ha sido utilizada, y potencialmente mal utilizada, para determinar la edad de las hembras de F. sparverius. [Traducción del equipo editorial]","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"258 1","pages":"1 - 5"},"PeriodicalIF":1.7,"publicationDate":"2022-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77046767","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}
Abstract. I evaluated the breeding biology of Red-headed Falcon (Falco chicquera) by documenting 39 breeding attempts in Surendranagar district of Gujarat, India, from 2006 to 2021. Across years, the Mayfield estimated seasonal nest survival was 0.900 ± 0.016 (95% CI), and productivity was 2.5 ± 1.4 (95% CI) fledglings per breeding attempt. Prey deliveries recorded during the study were exclusively birds, 71% of the order Passeriformes. Of the 39 breeding attempts in 18 territories, 26 nests were on high tension electricity transmission pylons and 13 were in trees. I provide the first baseline data for comparing and evaluating reproductive rate of this species in different environments across the Indian subcontinent and elsewhere. Resumen. Evalué la biología reproductiva de Falco chicquera documentando 39 intentos reproductivos en el distrito de Surendranagar de Gujarat, India, de 2006 a 2021. A lo largo de los años, la supervivencia estacional de los nidos, estimada por el método de Mayfield, fue de 0.900 ± 0.016 (IC del 95%), y la productividad fue de 2.5 ± 1.4 (95% IC) volantones por intento reproductivo. Las entregas de presas registradas durante el estudio fueron exclusivamente aves, con el 71% pertenecientes al Orden Passeriformes. De los 39 intentos reproductivos en 18 territorios, 26 nidos fueron colocados sobre postes eléctricos de alta tensión y 13 en árboles. Proporciono los primeros datos de referencia para comparar y evaluar la tasa reproductiva de esta especie en diferentes ambientes en el subcontinente indio y en otros lugares. [Traducción del equipo editorial]
摘要我通过记录2006年至2021年在印度古吉拉特邦Surendranagar地区的39次繁殖尝试来评估红头猎鹰(Falco chicquera)的繁殖生物学。多年来，Mayfield估计季节性巢存活率为0.900±0.016 (95% CI)，每次繁殖尝试的雏鸟产量为2.5±1.4 (95% CI)。在研究过程中记录的猎物都是鸟类，占雀形目的71%。在18个地区的39个繁殖尝试中，26个巢在高压输电塔上，13个巢在树上。我提供了第一个基线数据，用于比较和评估该物种在印度次大陆和其他地方不同环境下的繁殖率。Resumen。印度古吉拉特邦，印度，2006年至2021年。A lo largo de los años, la supervivencia estacional de los nidos, estimada por el m todo de Mayfield, fue de 0.900±0.016 (IC del 95%)， y la productividad fue de 2.5±1.4 (95% IC) volantones pintento reproductive tivo。在所有的建筑中，有71%的建筑是在公共道路上注册的。De los 39 intentos reproductivos en 18 territorios 26 nido fueron colocados尤其驿站街electricos De alta张力y arboles 13。在不同的环境下，特别是在次大陆和其他地区，对生殖能力的比较评价中，主要参考数据的比例损失。[Traducción del equipo社论]
{"title":"Reproductive Rate of the Red-Headed Falcon (Falco chicquera) in Surendranagar District, Gujarat, India","authors":"N. Bhatt","doi":"10.3356/JRR-21-73","DOIUrl":"https://doi.org/10.3356/JRR-21-73","url":null,"abstract":"Abstract. I evaluated the breeding biology of Red-headed Falcon (Falco chicquera) by documenting 39 breeding attempts in Surendranagar district of Gujarat, India, from 2006 to 2021. Across years, the Mayfield estimated seasonal nest survival was 0.900 ± 0.016 (95% CI), and productivity was 2.5 ± 1.4 (95% CI) fledglings per breeding attempt. Prey deliveries recorded during the study were exclusively birds, 71% of the order Passeriformes. Of the 39 breeding attempts in 18 territories, 26 nests were on high tension electricity transmission pylons and 13 were in trees. I provide the first baseline data for comparing and evaluating reproductive rate of this species in different environments across the Indian subcontinent and elsewhere. Resumen. Evalué la biología reproductiva de Falco chicquera documentando 39 intentos reproductivos en el distrito de Surendranagar de Gujarat, India, de 2006 a 2021. A lo largo de los años, la supervivencia estacional de los nidos, estimada por el método de Mayfield, fue de 0.900 ± 0.016 (IC del 95%), y la productividad fue de 2.5 ± 1.4 (95% IC) volantones por intento reproductivo. Las entregas de presas registradas durante el estudio fueron exclusivamente aves, con el 71% pertenecientes al Orden Passeriformes. De los 39 intentos reproductivos en 18 territorios, 26 nidos fueron colocados sobre postes eléctricos de alta tensión y 13 en árboles. Proporciono los primeros datos de referencia para comparar y evaluar la tasa reproductiva de esta especie en diferentes ambientes en el subcontinente indio y en otros lugares. [Traducción del equipo editorial]","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"25 1","pages":"75 - 80"},"PeriodicalIF":1.7,"publicationDate":"2022-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85611064","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}
Mark S. Martell, A. Archer, Amber Burnette, Mary W. Lee, Frank J. Nicoletti, Kristin A. L. Hall
Abstract. Understanding breeding ground dispersal, migratory timing and routes, and winter distribution of birds that are facing population declines, such as the American Kestrel (Falco sparverius), can provide insight into their life history traits and potentially inform management decisions. We used Lotek NanoTags and CTT LifeTags to track American Kestrels breeding in three locations in Minnesota, USA, across the Motus network. We tagged nine juvenile American Kestrels in July and August 2020 and 24 more kestrels between April and August 2021 (21 adults and three juveniles). We subsequently detected 15 (45%) of the 33 birds tagged. Eleven birds (33%) were detected while still on their breeding grounds; detections on the breeding grounds after tag deployment lasted an average of 64.3 d (SD = 59.7 d) and 19.9 d (SD = 13.2 d) for adults and juveniles, respectively. Two of the three juvenile males left their natal area 44 d after fledging and the third left 68 d after fledging. However, the average date of departure did not differ by age or sex. Twelve of 33 tagged birds (39%) were detected at post-breeding ground locations during flybys (25 events) or stopovers (2 events), and they all followed a relatively consistent migratory pathway from Minnesota through Iowa and Missouri. However, a lack of Motus receiver stations south of Missouri limited our ability to determine wintering areas. The use of the Motus system to determine dispersal and migratory pathways of American Kestrels, while currently limited in the central part of North America by the availability of receiver stations, is a valuable tool in furthering our understanding of American Kestrel life cycles and possibly revealing causes of the species' population decline in North America. Resumen. Comprender la dispersión en las zonas de reproducción, el momento y las rutas migratorias y la distribución invernal de las aves que se enfrentan a una disminución de la población, como Falco sparverius, puede proporcionar información sobre sus rasgos de historia de vida y potencialmente contribuir a las decisiones de gestión. Usamos Lotek NanoTags y CTT LifeTags para rastrear individuos de F. sparverius que se reproducen en tres lugares de Minnesota, EEUU, a través de la red Motus. Marcamos nueve juveniles de F. sparverius en julio y agosto de 2020 y 24 individuos más entre abril y agosto de 2021 (21 adultos y tres juveniles). Posteriormente detectamos 15 (45%) de las 33 aves marcadas. Once aves (33%) fueron detectadas mientras aún se encontraban en sus áreas de reproducción; las detecciones en las áreas reproductivas después de la colocación de las marcas alcanzaron un promedio de 64.3 d (DE = 59.7 d) y 19.9 d (DE = 13.2 d) para adultos y juveniles, respectivamente. Dos de los tres machos juveniles abandonaron su área natal 44 d después de emplumar y el tercero lo hizo 68 d después de emplumar. Sin embargo, la fecha promedio de partida no difirió por edad o sexo. Doce de las 33 aves marcadas (39%
摘要了解美国红隼(Falco sparverius)等面临种群减少的鸟类的繁殖地分布、迁徙时间和路线以及冬季分布，可以深入了解它们的生活史特征，并可能为管理决策提供信息。我们使用Lotek NanoTags和CTT LifeTags通过Motus网络在美国明尼苏达州的三个地点跟踪美国红隼的繁殖。我们在2020年7月和8月对9只美国红隼幼鸟进行了标记，并在2021年4月至8月期间对24只红隼(21只成年红隼和3只幼年红隼)进行了标记。随后，我们在标记的33只鸟中检测到15只(45%)。11只(33%)仍在繁殖地被发现;标签投放后，成虫和幼虫在繁殖地的平均探测时间分别为64.3 d (SD = 59.7 d)和19.9 d (SD = 13.2 d)。其中两只在羽化后44天离开了出生地，另一只在羽化后68天离开了出生地。然而，平均离职日期并没有因年龄或性别而异。在33只被标记的鸟类中，有12只(39%)在繁殖后的地点被发现，它们在飞越(25次)或中途停留(2次)期间都遵循从明尼苏达州到爱荷华州和密苏里州的相对一致的迁徙路径。然而，密苏里州南部缺乏Motus接收站限制了我们确定越冬地区的能力。利用Motus系统来确定美洲红隼的扩散和迁徙路径，虽然目前在北美中部地区受接收站可用性的限制，是进一步了解美洲红隼生命周期和可能揭示该物种在北美数量下降的原因的有价值的工具。Resumen。编译器为dispersión，编译器为reproducción，编译器为la distribución，编译器为la distribución，编译器为la población，编译器为Falco sparverius，编译器为información，编译器为编译器为gestión，编译器为编译器为gestión。Usamos Lotek纳米标签(CTT LifeTags)在美国明尼苏达州、欧洲联盟(eeu)的树木上复制了F. sparverius的超光谱个体，并在美国的Motus上进行了实验。Marcamos nueve juvenes de F. sparverius en julio y agostto de 2020 y 24个个体más entre abril y agostto de 2021(21个成人和3个青少年)。后检15例(45%)，共33例。1次(33%)检出率:1次(33%)检出率:1次(33%)检出率:1次(33%)检出率:1次(33%)检出率:aún 1次(33%)检出率:áreas 1次(33%);成年鼠和幼年鼠分别为64.3 d (de = 59.7 d)和19.9 d (de = 13.2 d)。Dos de los trres少年犯被遗弃在área出生后44岁和68岁以下的青少年中。在禁运期间，la fecha promedio de partida no difirió穷得可怜。在明尼苏达州、爱荷华州和密苏里州，有33只山羊(39%)、3只山羊(39%)、3只山羊(33%)、3只山羊(33%)、3只山羊(33%)、3只山羊(33%)、3只山羊(33%)、3只山羊(33%)、3只山羊(33%)、3只山羊(33%)、3只山羊(33%)、3只山羊(33%)、3只山羊(33%)、3只山羊(33%)、3只山羊(33%)、3只山羊(33%)、3只山羊(33%)、3只山羊(33%)、3只山羊(33%)、3只山羊(33%)、3只山羊(33%)、3只山羊(33%)。在禁运期间，密苏里州州的土地资源受体的变化limitó关于确定的新能力áreas关于invernada。El uso del sistema运动对位确定拉斯维加斯太阳migratorias y de色散·德·f·sparverius aunque目前esta limitado en la部分中央de美国del Norte关于disponibilidad de estaciones receptoras, es una herramienta valiosa对位mejorar nuestra称comprension秘鲁de los ciclos de维达·德·f·sparverius y posiblemente对位revelar las起见de la disminucion de la poblacion de la especie del Norte在美国。[Traducción del equipo社论]
{"title":"Using the Motus System to Track Post-Breeding Dispersal of American Kestrels Nesting in Minnesota, USA","authors":"Mark S. Martell, A. Archer, Amber Burnette, Mary W. Lee, Frank J. Nicoletti, Kristin A. L. Hall","doi":"10.3356/JRR-22-27","DOIUrl":"https://doi.org/10.3356/JRR-22-27","url":null,"abstract":"Abstract. Understanding breeding ground dispersal, migratory timing and routes, and winter distribution of birds that are facing population declines, such as the American Kestrel (Falco sparverius), can provide insight into their life history traits and potentially inform management decisions. We used Lotek NanoTags and CTT LifeTags to track American Kestrels breeding in three locations in Minnesota, USA, across the Motus network. We tagged nine juvenile American Kestrels in July and August 2020 and 24 more kestrels between April and August 2021 (21 adults and three juveniles). We subsequently detected 15 (45%) of the 33 birds tagged. Eleven birds (33%) were detected while still on their breeding grounds; detections on the breeding grounds after tag deployment lasted an average of 64.3 d (SD = 59.7 d) and 19.9 d (SD = 13.2 d) for adults and juveniles, respectively. Two of the three juvenile males left their natal area 44 d after fledging and the third left 68 d after fledging. However, the average date of departure did not differ by age or sex. Twelve of 33 tagged birds (39%) were detected at post-breeding ground locations during flybys (25 events) or stopovers (2 events), and they all followed a relatively consistent migratory pathway from Minnesota through Iowa and Missouri. However, a lack of Motus receiver stations south of Missouri limited our ability to determine wintering areas. The use of the Motus system to determine dispersal and migratory pathways of American Kestrels, while currently limited in the central part of North America by the availability of receiver stations, is a valuable tool in furthering our understanding of American Kestrel life cycles and possibly revealing causes of the species' population decline in North America. Resumen. Comprender la dispersión en las zonas de reproducción, el momento y las rutas migratorias y la distribución invernal de las aves que se enfrentan a una disminución de la población, como Falco sparverius, puede proporcionar información sobre sus rasgos de historia de vida y potencialmente contribuir a las decisiones de gestión. Usamos Lotek NanoTags y CTT LifeTags para rastrear individuos de F. sparverius que se reproducen en tres lugares de Minnesota, EEUU, a través de la red Motus. Marcamos nueve juveniles de F. sparverius en julio y agosto de 2020 y 24 individuos más entre abril y agosto de 2021 (21 adultos y tres juveniles). Posteriormente detectamos 15 (45%) de las 33 aves marcadas. Once aves (33%) fueron detectadas mientras aún se encontraban en sus áreas de reproducción; las detecciones en las áreas reproductivas después de la colocación de las marcas alcanzaron un promedio de 64.3 d (DE = 59.7 d) y 19.9 d (DE = 13.2 d) para adultos y juveniles, respectivamente. Dos de los tres machos juveniles abandonaron su área natal 44 d después de emplumar y el tercero lo hizo 68 d después de emplumar. Sin embargo, la fecha promedio de partida no difirió por edad o sexo. Doce de las 33 aves marcadas (39%","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"7 1","pages":"1 - 10"},"PeriodicalIF":1.7,"publicationDate":"2022-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75355256","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}
Golden Eagles (Aquila chrysaetos) are uncommon residents in the densely populated south San Francisco Bay area, California, USA, especially within the city of San Jose (Bousman 2007). Nesting Golden Eagles have not been reported within the city limits since 1892 (Barlow 1893, California Department of Fish and Wildlife 2021). Contributing factors for this absence might include limited foraging and nesting habitat. Golden Eagles typically nest on cliffs and tall trees (Katzner et al. 2020) such as pine trees (Pinus spp.), oaks (Quercus spp.), and eucalyptus (Eucalyptus spp.; Bousman 2007). Regionally, they nest in remote areas at higher elevations in the adjacent ranges and foothills to the east and west of San Jose. Here we describe our observations of Golden Eagles nesting in a Canary Island date palm tree (Phoenix canariensis) on the valley floor in approximately 202 ha of open grasslands adjacent to the San Jose–Santa Clara Regional Wastewater Facility (RWF) within the city of San Jose (37.42469468N, 121.95074798W). A pair has nested in the same stand of trees there for five consecutive years, 2018–2022. The RWF is located north of Highway 237 and south of the Don Edwards National Wildlife Refuge at the southern end of the San Francisco Bay. The ridgeline of the Diablo Range is approximately 10 km to the east and the Santa Cruz Mountains ridge is approximately 24 km to the west of the site. The ruderal grassland adjacent to the RWF formerly provided a safety zone (hereafter, bufferlands) between the RWF and surrounding residential areas when large quantities of chlorine were stored at the facility as part of its normal operations. At present, the bufferlands provide foraging and nesting habitat for several raptor species including White-tailed Kites (Elanus leucurus), American Kestrels (Falco sparverius), and Burrowing Owls (Athene cunicularia). Since 2013, we have conducted yearround monthly surveys for Burrowing Owls at this location. We conducted surveys during a 4–5 hr time-period, and we performed other tasks during additional opportunistic site visits during the peak of the Burrowing Owl breeding season (April–August). During these surveys, we occasionally observed a single Golden Eagle foraging, usually during fall and winter. However, starting November 2017, we regularly observed a pair of Golden Eagles hunting for California ground squirrels (Otospermophilus beecheyi) and roosting in a small stand of Canary Island date palm trees located in the center of the site at an elevation of approximately 10 m above mean sea level. We confirmed a large nest among the fronds of the biggest palm tree (diameter at breast height: 108 cm) in May 2018. The nest was approximately 10 m above ground on the northeast side of the tree. We inspected the nest structure using binoculars and examined nest material we found on the ground in January 2021 after a high-wind event. The nest was constructed primarily of eucalyptus branches, most likely from two tree
金雕(Aquila chrysaetos)是美国加利福尼亚州人口稠密的南旧金山湾区的罕见居民，特别是在圣何塞市(Bousman 2007)。自1892年以来，在城市范围内没有发现筑巢的金雕(Barlow 1893, California Department of Fish and Wildlife 2021)。造成这种缺失的因素可能包括觅食和筑巢栖息地的限制。金雕通常在悬崖和高大的树木上筑巢(Katzner et al. 2020)，如松树(Pinus spp.)、橡树(Quercus spp.)和桉树(eucalyptus spp.);Bousman 2007)。从地区上看，它们在圣何塞东部和西部邻近的山脉和丘陵地带的高海拔偏远地区筑巢。在这里，我们描述了我们在圣何塞市(37.42469468N, 121.95074798W)内圣何塞-圣克拉拉地区污水处理设施(RWF)附近约202公顷的开放草地上的加那利岛椰枣树(Phoenix canariensis)上对金雕筑巢的观察。从2018年到2022年，一对大熊猫已经连续五年在同一片树林里筑巢。RWF位于237号高速公路以北，旧金山湾南端的唐·爱德华兹国家野生动物保护区以南。迪亚波罗山脉(Diablo Range)的山脊线以东约10公里，圣克鲁斯山脉(Santa Cruz Mountains)的山脊以西约24公里。毗邻RWF的原始草原以前在RWF和周围居民区之间提供了一个安全区(以下简称缓冲区)，作为其正常运作的一部分，大量氯被储存在该设施中。目前，这片缓冲地带为白尾鸢(Elanus leucurus)、美洲红隼(Falco sparverius)和穴鸮(Athene culcularia)等几种猛禽提供了觅食和筑巢的栖息地。自2013年以来，我们每年都会在这个地方对穴鸮进行月度调查。我们在4-5小时的时间内进行了调查，并在穴鸮繁殖季节(4 - 8月)的高峰期进行了额外的机会性实地考察。在这些调查中，我们偶尔会观察到一只金鹰在觅食，通常是在秋天和冬天。然而，从2017年11月开始，我们定期观察到一对金雕捕食加利福尼亚地松鼠(otospermoophilus beecheyi)，并栖息在位于遗址中心的加那利岛枣椰树的一小片林里，海拔约为平均海拔10米。我们于2018年5月在最大的棕榈树(胸高直径:108厘米)的叶子中确认了一个大巢。巢在离地面大约10米的地方，在树的东北侧。我们使用双筒望远镜检查了巢结构，并检查了2021年1月大风事件后在地面上发现的巢材料。巢主要是用桉树树枝建造的，很可能是棕榈树旁边的两棵树。其他筑巢材料包括棕榈叶和芥菜(芸苔属)茎。在掉落的巢穴材料中，我们发现了大约31具加利福尼亚地松鼠的尸体，这是金雕的常见猎物(Wiens et al. 2018, Brown et al. 2021)。我们没有发现任何其他物种的猎物残骸。据我们所知，这是第一次在城市环境中发现金鹰在棕榈树上筑巢。离鸟巢最近的发展是东北366米的RWF设施。办公大楼沿着西南394米的围栏排列，高速公路与南面的缓冲区接壤，距离鸟巢578米。繁殖期金雕的活动范围很少超过距离其领地中心3公里的范围(Watson et al. 2014)。巢3.2公里范围内的大部分地区都是密集开发的土地，包括两条主要高速公路、商业和住宅开发、一个垃圾填埋场和一个回收中心。圣克鲁斯掠食性鸟类研究小组(1999)在加利福尼亚利弗莫尔以东的阿尔塔蒙特山口(RWF东北约65公里)研究了金雕的种群，发现除了几对外，所有的金雕都有一个电子邮件地址:philip.higgins@talonecological.org
{"title":"Golden Eagles Nesting in an Urban Setting in a Canary Island Date Palm Tree, San Jose, California","authors":"Philip G. Higgins, S. Menzel","doi":"10.3356/JRR-21-57","DOIUrl":"https://doi.org/10.3356/JRR-21-57","url":null,"abstract":"Golden Eagles (Aquila chrysaetos) are uncommon residents in the densely populated south San Francisco Bay area, California, USA, especially within the city of San Jose (Bousman 2007). Nesting Golden Eagles have not been reported within the city limits since 1892 (Barlow 1893, California Department of Fish and Wildlife 2021). Contributing factors for this absence might include limited foraging and nesting habitat. Golden Eagles typically nest on cliffs and tall trees (Katzner et al. 2020) such as pine trees (Pinus spp.), oaks (Quercus spp.), and eucalyptus (Eucalyptus spp.; Bousman 2007). Regionally, they nest in remote areas at higher elevations in the adjacent ranges and foothills to the east and west of San Jose. Here we describe our observations of Golden Eagles nesting in a Canary Island date palm tree (Phoenix canariensis) on the valley floor in approximately 202 ha of open grasslands adjacent to the San Jose–Santa Clara Regional Wastewater Facility (RWF) within the city of San Jose (37.42469468N, 121.95074798W). A pair has nested in the same stand of trees there for five consecutive years, 2018–2022. The RWF is located north of Highway 237 and south of the Don Edwards National Wildlife Refuge at the southern end of the San Francisco Bay. The ridgeline of the Diablo Range is approximately 10 km to the east and the Santa Cruz Mountains ridge is approximately 24 km to the west of the site. The ruderal grassland adjacent to the RWF formerly provided a safety zone (hereafter, bufferlands) between the RWF and surrounding residential areas when large quantities of chlorine were stored at the facility as part of its normal operations. At present, the bufferlands provide foraging and nesting habitat for several raptor species including White-tailed Kites (Elanus leucurus), American Kestrels (Falco sparverius), and Burrowing Owls (Athene cunicularia). Since 2013, we have conducted yearround monthly surveys for Burrowing Owls at this location. We conducted surveys during a 4–5 hr time-period, and we performed other tasks during additional opportunistic site visits during the peak of the Burrowing Owl breeding season (April–August). During these surveys, we occasionally observed a single Golden Eagle foraging, usually during fall and winter. However, starting November 2017, we regularly observed a pair of Golden Eagles hunting for California ground squirrels (Otospermophilus beecheyi) and roosting in a small stand of Canary Island date palm trees located in the center of the site at an elevation of approximately 10 m above mean sea level. We confirmed a large nest among the fronds of the biggest palm tree (diameter at breast height: 108 cm) in May 2018. The nest was approximately 10 m above ground on the northeast side of the tree. We inspected the nest structure using binoculars and examined nest material we found on the ground in January 2021 after a high-wind event. The nest was constructed primarily of eucalyptus branches, most likely from two tree","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"18 1","pages":"114 - 115"},"PeriodicalIF":1.7,"publicationDate":"2022-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86093982","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}
As secondary cavity nesters, American Kestrels (Falco sparverius) adapt readily to nest boxes, so most documentations and enumerations of their prey have been from boxes during the approximately 30-d nestling period (Smallwood and Bird 2020). Sherrod (1978), summarizing six North American studies of American Kestrel prey by numbers, not mass, showed that invertebrates (74%) were most often captured, though mammals (16%), birds (9%), and reptiles (1%) were also taken. However, in 2017 at 975 m elevation in the semi-arid southern Great Plains of northwestern Texas, reptiles (74.8%) were by far the most frequent kestrel prey recorded on motion-activated video cameras, while invertebrates, mammals, and birds made up 18.2%, 4.4%, and 2.9%, respectively (Boal et al. 2021). Of 187 mammals documented, 121 (64.7%) recorded were .42 g and ,75 g (Boal et al. 2021), which represented 38– 68% of the mass of an average 110-g American Kestrel male (Smallwood and Bird 2020). Thus, the capability of this species to repeatedly capture prey up to two-thirds their own mass has been previously reported. From 1995 to 2020 American Kestrels occupied one (n1⁄4 14) or both (n1⁄4 11) of two nest boxes 250 m apart in the Eldorado at Santa Fe (ESF) subdivision 15 km south of Santa Fe, New Mexico, USA. They successfully fledged young on 35 of 36 (97.2% fledging success) attempts during 50 (72% occupancy rate) nest box years; the second box became available in 1997. ESF is at 2000–2100 m elevation in piñon pine (Pinus edulis)-juniper (Juniperus spp.) savannah with groundcover dominated by blue grama (Bouteloua gracilis); it was converted from ranchland to housing starting in 1972. Large lots (0.5–1 ha), limits to yard/garden size, and extensive greenbelts resulted in a largely intact, ungrazed, natural habitat and prey base. Prey deliveries to one box regularly observed were approximately 67% (n1⁄4 29) reptilian between 1996 and 2009, though observations were opportunistic rather than standardized (Stahlecker and Cartron 2010). I visited nest boxes to band nestlings 2–3 wk after I began to see prey deliveries. I usually ignored the conglomeration of prey remains, particularly legs and carapaces of invertebrates, to complete the banding in a minimal time. However, on 8 July 2018, I found five tails of Ord’s kangaroo rats (Dipodomys ordii) in Box 1, and an additional tail in Box 2. The typical mass of D. ordii is approximately 52 g (Jones 1985), or 47% of the mass of an average American Kestrel male. The young in Box 1 were 13–15 d old and those in Box 2 were 7–10 d old, based on a photographic guide (Griggs and Steenhof 1993). The D. ordii were likely brought to the boxes by the males, as females forage very little early in the nestling period, but instead brood, feed, and defend the nestlings (Smallwood and Bird 2020). No species of kangaroo rat has, to my knowledge, been previously reported as prey of the American Kestrel. All 20 species in the genus Dipodomys are primarily
作为次级腔巢，美洲红隼(Falco sparverius)很容易适应巢箱，因此大多数对其猎物的记录和计数都是在大约30天的雏鸟期间从箱中进行的(Smallwood and Bird 2020)。Sherrod(1978)总结了北美对红隼猎物数量而非质量的六项研究，表明无脊椎动物(74%)最常被捕获，尽管哺乳动物(16%)，鸟类(9%)和爬行动物(1%)也被捕获。然而，2017年，在德克萨斯州西北部半干旱的大平原南部海拔975米的地方，运动激活摄像机记录到的红隼最常见的猎物是爬行动物(74.8%)，而无脊椎动物、哺乳动物和鸟类分别占18.2%、4.4%和2.9% (Boal et al. 2021)。在记录的187只哺乳动物中，121只(64.7%)的体重分别为0.42 g和0.75 g (Boal et al. 2021)，占美国红隼平均体重(110 g)的38 - 68% (Smallwood and Bird 2020)。因此，这一物种有能力反复捕获高达自身体重三分之二的猎物。从1995年到2020年，美国红隼在美国新墨西哥州圣达菲以南15公里的Eldorado at Santa Fe (ESF)分区占据了两个相距250米的巢箱中的一个(n1⁄4 14)或两个(n1⁄4 11)。50年(占巢率72%)中，36次羽化尝试中有35次羽化成功(97.2%);第二个盒子于1997年上市。piñon松(Pinus edulis)-杜松(Juniperus spp.)热带稀树草原的ESF在海拔2000-2100 m，地被植物以蓝草(boueloua gracilis)为主;从1972年开始，它从牧场变成了住宅。大片土地(0.5-1公顷)，限制庭院/花园的大小，以及广泛的绿地形成了一个基本完整的、未放牧的自然栖息地和猎物基地。1996年至2009年期间，定期观察到大约67% (n1 / 4 29)的爬行动物被送到一个盒子里，尽管观察是机会性的，而不是标准化的(Stahlecker和Cartron 2010)。在我开始看到猎物分娩后的2-3周，我去了巢箱给雏鸟戴上了绷带。我通常忽略了猎物残骸的聚集，特别是无脊椎动物的腿和甲壳，以便在最短的时间内完成绑带。然而，在2018年7月8日，我在盒子1中发现了五条Ord 's袋鼠鼠(Dipodomys ordii)的尾巴，在盒子2中又发现了一条尾巴。红隼的典型体重约为52克(Jones 1985)，是美洲红隼雄性平均体重的47%。根据图片指南(Griggs and Steenhof 1993)，盒1的幼崽年龄为13-15天，盒2的幼崽年龄为7-10天。ordii可能是由雄性带到盒子里的，因为雌性在雏鸟时期很少觅食，而是孵蛋、喂养和保护雏鸟(Smallwood and Bird 2020)。据我所知，以前没有任何一种袋鼠鼠被报道为美洲红隼的猎物。Dipodomys属的所有20种主要是夜间花岗岩动物(Lockard and Owings 1974, Reichman and Price 1993)，这些似乎是白天活动的猛禽所没有的。Dipodomys可能是从附近筑巢的大角猫头鹰(Bubo virginianus)那里捡来的(Stahlecker 2015)，但我看到成年猫头鹰和3周大的猫头鹰幼崽都吞下了Dipodomys的后腿，包括整个尾巴，所以它们可能没有留下任何东西可以吃。此外，美国红隼的食腐事件只发表过两次，都发生在冬天;被吃掉的是一只腐烂的东方尖嘴猫头鹰(Megascops);Ganis 1976)和一只大型家火鸡(Meleagris gallopavo;Schulwitz et al. 2019)。据报道，袋鼠鼠是四种昼行性猛禽的猎物，包括斯温森鹰(Buteo swainsonii;Bednarz 1988;Dipodomys spp。Snyder and Snyder 1991;独角鹰(Parabuteo unicinctus);Bednarz 1988;铁锈鹰(B. regalis;Olendorff 1993;92.5%弓形虫;Cartron et al. 2004;草原隼(Falco mexicanus);Steenhof 2020;Dipodomys spp)。类似地，Daley et al.(2000)报告了Loggerhead的捕食行为，其电子邮件地址为:dale@eagleenvironmental.net
{"title":"Largely Nocturnal Kangaroo Rats Preyed Upon by Diurnal American Kestrels in New Mexico","authors":"D. Stahlecker","doi":"10.3356/JRR-22-33","DOIUrl":"https://doi.org/10.3356/JRR-22-33","url":null,"abstract":"As secondary cavity nesters, American Kestrels (Falco sparverius) adapt readily to nest boxes, so most documentations and enumerations of their prey have been from boxes during the approximately 30-d nestling period (Smallwood and Bird 2020). Sherrod (1978), summarizing six North American studies of American Kestrel prey by numbers, not mass, showed that invertebrates (74%) were most often captured, though mammals (16%), birds (9%), and reptiles (1%) were also taken. However, in 2017 at 975 m elevation in the semi-arid southern Great Plains of northwestern Texas, reptiles (74.8%) were by far the most frequent kestrel prey recorded on motion-activated video cameras, while invertebrates, mammals, and birds made up 18.2%, 4.4%, and 2.9%, respectively (Boal et al. 2021). Of 187 mammals documented, 121 (64.7%) recorded were .42 g and ,75 g (Boal et al. 2021), which represented 38– 68% of the mass of an average 110-g American Kestrel male (Smallwood and Bird 2020). Thus, the capability of this species to repeatedly capture prey up to two-thirds their own mass has been previously reported. From 1995 to 2020 American Kestrels occupied one (n1⁄4 14) or both (n1⁄4 11) of two nest boxes 250 m apart in the Eldorado at Santa Fe (ESF) subdivision 15 km south of Santa Fe, New Mexico, USA. They successfully fledged young on 35 of 36 (97.2% fledging success) attempts during 50 (72% occupancy rate) nest box years; the second box became available in 1997. ESF is at 2000–2100 m elevation in piñon pine (Pinus edulis)-juniper (Juniperus spp.) savannah with groundcover dominated by blue grama (Bouteloua gracilis); it was converted from ranchland to housing starting in 1972. Large lots (0.5–1 ha), limits to yard/garden size, and extensive greenbelts resulted in a largely intact, ungrazed, natural habitat and prey base. Prey deliveries to one box regularly observed were approximately 67% (n1⁄4 29) reptilian between 1996 and 2009, though observations were opportunistic rather than standardized (Stahlecker and Cartron 2010). I visited nest boxes to band nestlings 2–3 wk after I began to see prey deliveries. I usually ignored the conglomeration of prey remains, particularly legs and carapaces of invertebrates, to complete the banding in a minimal time. However, on 8 July 2018, I found five tails of Ord’s kangaroo rats (Dipodomys ordii) in Box 1, and an additional tail in Box 2. The typical mass of D. ordii is approximately 52 g (Jones 1985), or 47% of the mass of an average American Kestrel male. The young in Box 1 were 13–15 d old and those in Box 2 were 7–10 d old, based on a photographic guide (Griggs and Steenhof 1993). The D. ordii were likely brought to the boxes by the males, as females forage very little early in the nestling period, but instead brood, feed, and defend the nestlings (Smallwood and Bird 2020). No species of kangaroo rat has, to my knowledge, been previously reported as prey of the American Kestrel. All 20 species in the genus Dipodomys are primarily ","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"504 1","pages":"1 - 3"},"PeriodicalIF":1.7,"publicationDate":"2022-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77072070","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}
K. Biles, J. Bednarz, S. Schulwitz, Jeff A. Johnson
Abstract. The American Kestrel (Falco sparverius) is a small falcon whose population is declining across North America, but drivers of this decline have yet to be identified. Conservationists have called for greater understanding of kestrels' migratory connectivity to identify potential causes of decline that may occur during various parts of their annual cycle. For many bird species, the most common and direct way to determine migratory connectivity is by attaching a tracking device that documents their locations over time. However, American Kestrels present a challenge when attaching tracking devices due to their small size and aggressive biting capabilities. We used two attachment methods (backpack and leg-loop harnesses) commonly used for raptors on a wintering population of American Kestrels in north Texas to test whether there were differences in observed return rates the following year. Of 20 American Kestrels fit with devices, significantly more of the kestrels fit with backpack harnesses were observed the following winter than the birds fit with leg-loop harnesses. Eight of the 10 kestrels we fit with backpacks were observed to return to their winter territories compared to only two of 10 kestrels fit with leg-loops. Overall return frequency data of kestrels with both harnessing methods (50%, n = 20) was similar to the frequency we observed on marked birds without devices (52%, n = 190), though this was heavily skewed due to the high return of birds with backpack harnesses (80%). Although our sample size was limited, the disparity between the return rates of birds with the two harness types suggests that backpack harnesses are the preferred method of attaching tracking devices to American Kestrels, and also potentially to similar small raptor species. Resumen. Falco sparverius es un pequeño halcón cuya población está disminuyendo en América del Norte, pero aún no se han identificado los factores que causan esta disminución. Los conservacionistas han abogado por una mayor comprensión de la conectividad migratoria de esta especie para identificar las posibles causas de disminución que pueden ocurrir durante varias partes de su ciclo anual. Para muchas especies de aves, la forma más común y directa de determinar la conectividad migratoria es colocando sobre ellas un dispositivo de seguimiento que documente sus ubicaciones a lo largo del tiempo. Sin embargo, F. sparverius presenta un desafío al momento de fijar los dispositivos de seguimiento, debido a su pequeño tamaño y su capacidad para picotear agresivamente. Usamos dos métodos de fijación (arneses de mochila y pélvicos), comúnmente empleados para aves rapaces, en una población de F. sparverius invernante en el norte de Texas, para probar si había diferencias en las tasas de retorno observadas al año siguiente. De los 20 individuos equipados con dispositivos, se observaron significativamente más ejemplares provistos con arneses de mochila en el invierno siguiente que aves provistas con a
摘要美洲红隼(Falco sparverius)是一种小型猎鹰，其数量在北美各地正在下降，但这种下降的原因尚未确定。环保人士呼吁对红隼的迁徙连通性进行更深入的了解，以确定在其年度周期的不同阶段可能发生的数量下降的潜在原因。对于许多鸟类来说，确定迁徙连通性的最常见和最直接的方法是通过附加跟踪设备记录它们随时间的位置。然而，美国红隼在安装跟踪设备时提出了一个挑战，因为它们体积小，咬人能力强。我们使用了两种通常用于猛禽的附着方法(背包和腿环安全带)，以测试在德克萨斯州北部的美国红隼越冬种群中观察到的次年的返回率是否存在差异。在20只安装了装置的美国红隼中，在接下来的冬天，我们观察到更多的红隼安装了背包背带，而不是腿环背带。我们观察到，背着背包的10只红隼中有8只会返回它们的冬季领地，而背着腿环的10只红隼中只有2只会返回。使用两种方法的红隼的总体返回频率数据(50%，n = 20)与我们在没有装置的标记鸟(52%，n = 190)上观察到的频率相似，尽管由于使用双肩式背带的鸟的高返回率(80%)，这一数据严重倾斜。尽管我们的样本量有限，但使用两种背带的鸟类返回率之间的差异表明，背包背带是美国红隼(kestretel)和类似小型猛禽(raptor)的首选跟踪设备。Resumen。Falco sparverius unpequeño halcón cuya población estminuyenddo en amsamica del Norte, pero aún没有发现任何确定的因素，但没有发现任何原因disminución。环保主义者认为，每年在不同的地方都有可能发生类似的情况，例如:comprensión de la conectividad migratoria de esta。在大多数情况下，通过直接确定迁徙者的迁徙行为的形式más común可以确定迁徙者的迁徙行为，但不确定迁徙者的迁徙行为是否具有决定性，因此不确定迁徙者的迁徙行为是否具有决定性，因此不确定迁徙者的迁徙行为是否具有决定性。在禁运期间，斯帕维里乌斯提出了一项建议，即desafío所有的时间都是关于如何处理这些问题的，如何处理这些问题pequeño tamaño是关于如何处理这些问题的。Usamos dos msamododos fijación (mochila和psamovicos)， comúnmente empleados para - rapaces，以及población de F. sparverius inverente和北德克萨斯州，para - probar si había不同的是，Usamos dos msamodododos fijación siguente。在这20个人中，我们观察到有重大意义的情况(más)，我们观察到有重大意义的情况(例如，我们观察到有重大意义的情况(例如，我们观察到有重大意义的情况)，我们观察到有重大意义的情况(例如，有重大意义的情况)。10个个人供应者从墨西哥境内的三个领土出发，从墨西哥境内的10个个人供应者到墨西哥境内的10个个人供应者到墨西哥境内的10个个人供应者。Los datos generales de frerecuencia de rereno de F. sparverius obtenidos con ambos msamotodos de arneses (50%， n = 20)，与la freuencia que observamos en las marcadas persinpositivevos (52%， n = 190)， unque esto estuvo muresgado debido al alto rereno de aves conneses de mochila(80%)相似。1 .特别报告员tamaño，特别报告员的资料，特别报告员的资料，特别报告员的资料，特别报告员的资料，特别报告员的资料，特别报告员的资料，特别报告员的资料，特别报告员的资料，特别报告员的资料，特别报告员的资料，特别报告员的资料，特别报告员的资料，特别报告员的资料，特别报告员的资料，特别报告员的资料，特别报告员的资料，特别报告员的资料，特别报告员的资料，特别报告员的资料，特别报告员的资料，特别报告员的资料，特别报告员的资料，特别报告员的资料tamaño类似。[Traducción del equipo社论]
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