P. Azkona, Carmelo Fernández, Iñigo Moreno, Marta Olalde, Joseba Carreras de Bergareche
ABSTRACT. Throughout Europe, electrocution on distribution power lines is the main cause of mortality for fledgling Bonelli's Eagles (Aquila fasciata) released into the wild through hacking. To attempt to reduce electrocutions, we subjected 17 fledglings that had not previously had any contact with power line pylons to aversive conditioning. To this end, we installed electrified barrier wires on two distribution pylons (one each of the two most common pylon types in northern Spain), which were disconnected from the electric grid. The electrified barriers, which were in place from 2020 through 2022, lightly shocked fledglings alighting on them. We compared the subsequent behavior of conditioned fledglings with that of a control sample of 19 unconditioned fledglings released between 2015 and 2019. The results suggest that conditioning results in (1) a delay in juveniles' use of distribution power line pylons as perches in the wild; (2) juveniles' avoidance of pylons in temporary settlement areas; and (3) a nonsignificant increase in juvenile survival rates during the first year of life. This approach may have applicability in other population reinforcement projects, and in areas with high concentrations (communal roosts and vulture restaurants) of other large raptors.
{"title":"Conditioning Fledgling Bonelli's Eagles (Aquila fasciata) to Avoid Power Line Pylons","authors":"P. Azkona, Carmelo Fernández, Iñigo Moreno, Marta Olalde, Joseba Carreras de Bergareche","doi":"10.3356/JRR-22-00108","DOIUrl":"https://doi.org/10.3356/JRR-22-00108","url":null,"abstract":"ABSTRACT. Throughout Europe, electrocution on distribution power lines is the main cause of mortality for fledgling Bonelli's Eagles (Aquila fasciata) released into the wild through hacking. To attempt to reduce electrocutions, we subjected 17 fledglings that had not previously had any contact with power line pylons to aversive conditioning. To this end, we installed electrified barrier wires on two distribution pylons (one each of the two most common pylon types in northern Spain), which were disconnected from the electric grid. The electrified barriers, which were in place from 2020 through 2022, lightly shocked fledglings alighting on them. We compared the subsequent behavior of conditioned fledglings with that of a control sample of 19 unconditioned fledglings released between 2015 and 2019. The results suggest that conditioning results in (1) a delay in juveniles' use of distribution power line pylons as perches in the wild; (2) juveniles' avoidance of pylons in temporary settlement areas; and (3) a nonsignificant increase in juvenile survival rates during the first year of life. This approach may have applicability in other population reinforcement projects, and in areas with high concentrations (communal roosts and vulture restaurants) of other large raptors.","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"33 1","pages":"533 - 543"},"PeriodicalIF":1.7,"publicationDate":"2023-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139153582","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}
Jason E. Bruggeman, Patricia L. Kennedy, David E. Andersen, Shelly Deisch, E. D. Stukel
ABSTRACT. Conservation of the American Goshawk (Accipiter atricapillus; hereafter goshawk) has been contentious in relation to forest management. Higher quality goshawk nesting habitat is generally considered to consist of contiguous tracts of mature forest, due to goshawks' large home ranges, territoriality, and food requirements. The large trees of mature forest have the greatest economic value to timber companies. We used long-term (1965–2019) data from 281 goshawk nest site locations in the Black Hills National Forest (BHNF), South Dakota, and Wyoming, USA, to evaluate (1) abiotic and biotic factors associated with goshawk nest site habitat suitability (hereafter habitat suitability); (2) changes in habitat suitability over time; and (3) the effect of anthropogenic activities and natural disturbances on habitat suitability. We evaluated forest attributes across five spatial scales relevant to goshawks, used information-theoretic methods to rank and select models, and assessed the predictive capability of the best-approximating models using the concordance statistic. The best-approximating model had excellent predictive capability (concordance = 0.821). Forest attributes at the 12-ha scale were a better predictor of goshawk habitat suitability than covariates evaluated at the point or >12-ha scales, indicating the importance of managing goshawk habitat beyond the nest tree, but within the nest stand. Goshawk habitat suitability was positively related to mean percent canopy cover and median canopy base height, and negatively related to variability in canopy base height within 12 ha of the location. As mean percent canopy cover within 12 ha of a location increased, goshawk habitat suitability increased more slowly in burned compared to unburned areas. Commercial thinning treatments were more likely to occur in closed canopy forest that already had a higher likelihood of goshawk nesting, and we documented a positive relationship between habitat suitability and the interaction of canopy cover with commercial thinning. Goshawk habitat suitability was negatively related to slope and distance to drainage bottoms, and positively related to distance to ridges, which may be related to microclimatic factors. Our results indicate goshawk habitat suitability decreased across the BHNF over the past three decades and much high-quality nesting habitat was lost during this period due to a combination of unsustainable timber harvest and natural disturbances. Minimizing forest management activities that decrease canopy cover and canopy base height, and increase variability in canopy base height in areas of high- and medium-quality goshawk habitat are likely to slow the loss of higher-quality habitat and allow development of future nesting habitat. In addition to informing management, this study demonstrates the value of using existing long-term legacy datasets in conjunction with time series of remotely sensed habitat attributes to evaluate changes in habitat su
{"title":"Declining American Goshawk (Accipiter atricapillus) Nest Site Habitat Suitability in a Timber Production Landscape: Effects of Abiotic, Biotic, and Forest Management Factors","authors":"Jason E. Bruggeman, Patricia L. Kennedy, David E. Andersen, Shelly Deisch, E. D. Stukel","doi":"10.3356/JRR-22-116","DOIUrl":"https://doi.org/10.3356/JRR-22-116","url":null,"abstract":"ABSTRACT. Conservation of the American Goshawk (Accipiter atricapillus; hereafter goshawk) has been contentious in relation to forest management. Higher quality goshawk nesting habitat is generally considered to consist of contiguous tracts of mature forest, due to goshawks' large home ranges, territoriality, and food requirements. The large trees of mature forest have the greatest economic value to timber companies. We used long-term (1965–2019) data from 281 goshawk nest site locations in the Black Hills National Forest (BHNF), South Dakota, and Wyoming, USA, to evaluate (1) abiotic and biotic factors associated with goshawk nest site habitat suitability (hereafter habitat suitability); (2) changes in habitat suitability over time; and (3) the effect of anthropogenic activities and natural disturbances on habitat suitability. We evaluated forest attributes across five spatial scales relevant to goshawks, used information-theoretic methods to rank and select models, and assessed the predictive capability of the best-approximating models using the concordance statistic. The best-approximating model had excellent predictive capability (concordance = 0.821). Forest attributes at the 12-ha scale were a better predictor of goshawk habitat suitability than covariates evaluated at the point or >12-ha scales, indicating the importance of managing goshawk habitat beyond the nest tree, but within the nest stand. Goshawk habitat suitability was positively related to mean percent canopy cover and median canopy base height, and negatively related to variability in canopy base height within 12 ha of the location. As mean percent canopy cover within 12 ha of a location increased, goshawk habitat suitability increased more slowly in burned compared to unburned areas. Commercial thinning treatments were more likely to occur in closed canopy forest that already had a higher likelihood of goshawk nesting, and we documented a positive relationship between habitat suitability and the interaction of canopy cover with commercial thinning. Goshawk habitat suitability was negatively related to slope and distance to drainage bottoms, and positively related to distance to ridges, which may be related to microclimatic factors. Our results indicate goshawk habitat suitability decreased across the BHNF over the past three decades and much high-quality nesting habitat was lost during this period due to a combination of unsustainable timber harvest and natural disturbances. Minimizing forest management activities that decrease canopy cover and canopy base height, and increase variability in canopy base height in areas of high- and medium-quality goshawk habitat are likely to slow the loss of higher-quality habitat and allow development of future nesting habitat. In addition to informing management, this study demonstrates the value of using existing long-term legacy datasets in conjunction with time series of remotely sensed habitat attributes to evaluate changes in habitat su","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"16 64","pages":"595 - 616"},"PeriodicalIF":1.7,"publicationDate":"2023-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139154479","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}
{"title":"Wildlife Tourism Malpractice Can Lead to Animal Poisoning with Plastics","authors":"Margarita Mulero-Pázmány","doi":"10.3356/JRR-22-00111","DOIUrl":"https://doi.org/10.3356/JRR-22-00111","url":null,"abstract":"","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"58 7","pages":"667 - 670"},"PeriodicalIF":1.7,"publicationDate":"2023-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139153168","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}
Eduardo F. Pavez, Paulo Pascual, Benito A. González
We here describe Andean Condors' (Vultur gryphus) use of the biggest landfill in Chile as a food source. We monitored the landfill between 2005 and 2022. Until 2013, there was an increase in the number of condors present in the landfill. Then the number decreased until 2016, coincident with an abundant food supply on a large spatial scale, due to high mortality of cattle that were affected by extreme drought and plentiful rabbit carcasses due to outbreaks of myxomatosis. The same temporal and numerical trends were observed in both sexes and all ages. Compared to published population parameters, in the landfill the proportion of immatures was higher and that of adult males was lower; therefore, the landfill could function as a subsidy mainly for the lower strata of the dominance hierarchy of this species. There was a strong seasonality, with a low presence of condors in the warm season and maximum numbers in the cold season, likely coinciding with seasonal movements of livestock between summer and winter range lands in the high mountains, resulting in lower food abundance for condors during the cold season. This is the first characterization of the use of a landfill by a high number of Andean Condors, use that could have implications for the species' population in central Chile. Despite the apparent positive effect as a subsidy, waste disposals can have detrimental effects due to condors' consumption of potentially dangerous compounds. This study underscores the opportunistic nature of the Andean Condor, a species that can take advantage of rubbish dumps. Long-term Andean Condor monitoring at landfills may serve as an indicator food supply over a large spatial scale, which should be considered in conservation strategies.
{"title":"Landfill Use by Andean Condors in Central Chile","authors":"Eduardo F. Pavez, Paulo Pascual, Benito A. González","doi":"10.3356/JRR-22-00051","DOIUrl":"https://doi.org/10.3356/JRR-22-00051","url":null,"abstract":"We here describe Andean Condors' (Vultur gryphus) use of the biggest landfill in Chile as a food source. We monitored the landfill between 2005 and 2022. Until 2013, there was an increase in the number of condors present in the landfill. Then the number decreased until 2016, coincident with an abundant food supply on a large spatial scale, due to high mortality of cattle that were affected by extreme drought and plentiful rabbit carcasses due to outbreaks of myxomatosis. The same temporal and numerical trends were observed in both sexes and all ages. Compared to published population parameters, in the landfill the proportion of immatures was higher and that of adult males was lower; therefore, the landfill could function as a subsidy mainly for the lower strata of the dominance hierarchy of this species. There was a strong seasonality, with a low presence of condors in the warm season and maximum numbers in the cold season, likely coinciding with seasonal movements of livestock between summer and winter range lands in the high mountains, resulting in lower food abundance for condors during the cold season. This is the first characterization of the use of a landfill by a high number of Andean Condors, use that could have implications for the species' population in central Chile. Despite the apparent positive effect as a subsidy, waste disposals can have detrimental effects due to condors' consumption of potentially dangerous compounds. This study underscores the opportunistic nature of the Andean Condor, a species that can take advantage of rubbish dumps. Long-term Andean Condor monitoring at landfills may serve as an indicator food supply over a large spatial scale, which should be considered in conservation strategies.","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"120 5","pages":"617 - 627"},"PeriodicalIF":1.7,"publicationDate":"2023-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139153939","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}
Matthew J. Bowers, Paula M. Orozco-Valor, Rebecca A. McCabe, J. Therrien
The American Kestrel (Falco sparverius) has been steadily declining throughout most of its eastern North American range, and the cause of this decline is still relatively unknown. As a cavity nesting species, the American Kestrel often competes with other cavity nesters such as the invasive and abundant European Starling (Sturnus vulgaris) over nest boxes. The relationship between European Starling presence at nesting sites and American Kestrel occupancy and nesting success is understudied. We analyzed data from nest boxes monitored in eastern Pennsylvania, USA, from 1992 to 2021 to identify changes in occupancy of American Kestrels and competitors, and to examine the relationship between competition at nest boxes and American Kestrel nesting parameters. We found that American Kestrel occupancy decreased while European Starling occupancy increased over the study period. All other species occupying nest boxes (small mammals, passerines, owls, and snakes) showed no significant occupancy trends. On average 21% of nest boxes remained unoccupied annually, and 7% of occupied nest boxes were used by both American Kestrels and competitors in the same breeding season. The presence of these competitors had negative associations with American Kestrel occupancy, clutch size, number of fledglings produced, and overall nesting success. Specifically, the rate of nesting success decreased by 26% when European Starlings used the same nest box within the same breeding season. In recent years, nesting productivity of American Kestrels has decreased, with the average number of nestlings, fledglings, and nesting success rate all declining, while the average clutch size remained constant. Our results suggest that American Kestrel nesting parameters in eastern Pennsylvania are negatively associated with competition for nest boxes during the breeding season. The opposing trends in occupancy for the European Starling and the American Kestrel in this study area coupled with the declining productivity of American Kestrel nests raise concerns over the future of this raptor species in eastern Pennsylvania.
{"title":"American Kestrels Compete with European Starlings over Nest Boxes in Eastern Pennsylvania","authors":"Matthew J. Bowers, Paula M. Orozco-Valor, Rebecca A. McCabe, J. Therrien","doi":"10.3356/jrr-22-88","DOIUrl":"https://doi.org/10.3356/jrr-22-88","url":null,"abstract":"\u0000 The American Kestrel (Falco sparverius) has been steadily declining throughout most of its eastern North American range, and the cause of this decline is still relatively unknown. As a cavity nesting species, the American Kestrel often competes with other cavity nesters such as the invasive and abundant European Starling (Sturnus vulgaris) over nest boxes. The relationship between European Starling presence at nesting sites and American Kestrel occupancy and nesting success is understudied. We analyzed data from nest boxes monitored in eastern Pennsylvania, USA, from 1992 to 2021 to identify changes in occupancy of American Kestrels and competitors, and to examine the relationship between competition at nest boxes and American Kestrel nesting parameters. We found that American Kestrel occupancy decreased while European Starling occupancy increased over the study period. All other species occupying nest boxes (small mammals, passerines, owls, and snakes) showed no significant occupancy trends. On average 21% of nest boxes remained unoccupied annually, and 7% of occupied nest boxes were used by both American Kestrels and competitors in the same breeding season. The presence of these competitors had negative associations with American Kestrel occupancy, clutch size, number of fledglings produced, and overall nesting success. Specifically, the rate of nesting success decreased by 26% when European Starlings used the same nest box within the same breeding season. In recent years, nesting productivity of American Kestrels has decreased, with the average number of nestlings, fledglings, and nesting success rate all declining, while the average clutch size remained constant. Our results suggest that American Kestrel nesting parameters in eastern Pennsylvania are negatively associated with competition for nest boxes during the breeding season. The opposing trends in occupancy for the European Starling and the American Kestrel in this study area coupled with the declining productivity of American Kestrel nests raise concerns over the future of this raptor species in eastern Pennsylvania.","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"336 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86789697","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}
Marek Dostál, I. Literák, D. Horal, J. Svetlik, R. Raab, J. Hohenegger, H. Matušík
The Red Kite (Milvus milvus) is a common raptor in suitable areas of Austria, the Czech Republic, and Slovakia during the nonbreeding season. However, the exact number of birds wintering in these countries remains unknown. Through an integrated approach using satellite telemetry, direct field surveys at nocturnal roosts, and citizen science databases, we estimated the wintering population of Red Kites in this area during the winter of 2020/2021. Based on three surveys taking place at the beginning (28 November 2020), middle (9 January 2021), and end (5 February 2021) of winter, respectively, we counted 566, 558, and 536 Red Kites. The observations from online citizen science databases mostly appeared to correspond with the area of communal roost sites. Using our combined approach, the estimates of wintering Red Kites were determined as minimum numbers in the study area. A comparison of historical data (from the second half of the 20th and beginning of the 21st centuries, respectively) and our own results suggests that the wintering population of Red Kites in the study area has increased substantially. This dynamic could be caused by changes in climatic conditions, a shift of the birds' breeding range in Europe, changes in migration behavior and/or food availability, and/or conservation efforts.
{"title":"Integrated Approach Improves Monitoring of Wintering Red Kites in Central Europe","authors":"Marek Dostál, I. Literák, D. Horal, J. Svetlik, R. Raab, J. Hohenegger, H. Matušík","doi":"10.3356/jrr-22-97","DOIUrl":"https://doi.org/10.3356/jrr-22-97","url":null,"abstract":"\u0000 The Red Kite (Milvus milvus) is a common raptor in suitable areas of Austria, the Czech Republic, and Slovakia during the nonbreeding season. However, the exact number of birds wintering in these countries remains unknown. Through an integrated approach using satellite telemetry, direct field surveys at nocturnal roosts, and citizen science databases, we estimated the wintering population of Red Kites in this area during the winter of 2020/2021. Based on three surveys taking place at the beginning (28 November 2020), middle (9 January 2021), and end (5 February 2021) of winter, respectively, we counted 566, 558, and 536 Red Kites. The observations from online citizen science databases mostly appeared to correspond with the area of communal roost sites. Using our combined approach, the estimates of wintering Red Kites were determined as minimum numbers in the study area. A comparison of historical data (from the second half of the 20th and beginning of the 21st centuries, respectively) and our own results suggests that the wintering population of Red Kites in the study area has increased substantially. This dynamic could be caused by changes in climatic conditions, a shift of the birds' breeding range in Europe, changes in migration behavior and/or food availability, and/or conservation efforts.","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"120 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77444454","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}
J. Kolowski, Caylen Wolfer, Megan McDaniels, Alan Williams, J. Harris
Long-term monitoring data indicate a persistent decline in American Kestrel populations across North America. Loss or alteration of habitat have been listed as potential causal factors, but basic information on kestrel space use, including breeding home range size, is lacking. No study has provided robust estimates of the ranging behavior of breeding kestrels based on tracking data of any resolution. We fitted 19 adult female kestrels with solar-powered GPS transmitters during the incubation period in northern Virginia. High-resolution tracking began during the early nestling stage for 17 birds. We collected an average of 1710 locations per bird through the end of the breeding season (31 August), with 13 birds tracked through the fledging of their young. Autocorrelated kernel density home range estimation showed that female kestrels used breeding home ranges that were smaller (average: 0.32 km2) than most previously published range sizes. Home ranges did not vary significantly in size across breeding stages and demonstrated little overlap with the ranges of neighboring kestrels. Five females shifted their territories in the post-breeding stage (i.e., after disappearance or dispersal of fledglings) between 1.5 and 12.3 km from their nest box; they maintained these new ranges at least to the migration period. We also documented home range excursion forays (n = 128) by all 12 consistently tracked females. Mean (4.0 km) and maximum (127.7 km) foray distances were some of the largest reported among birds and mammals relative to home range size. Weekly foray rates were highest during the nestling stage, and for birds that ultimately shifted from their breeding home range. The existence of long-distance foray behavior and the use of multiple summer home ranges, both shown here for the first time for this species, has a direct impact on interpretation of kestrel nest-site and habitat selection data, and on the assessment of potential threats to this species in the breeding season.
{"title":"High-resolution GPS Tracking of American Kestrels Reveals Breeding and Post-breeding Ranging Behavior in Northern Virginia, USA","authors":"J. Kolowski, Caylen Wolfer, Megan McDaniels, Alan Williams, J. Harris","doi":"10.3356/jrr-22-106","DOIUrl":"https://doi.org/10.3356/jrr-22-106","url":null,"abstract":"\u0000 Long-term monitoring data indicate a persistent decline in American Kestrel populations across North America. Loss or alteration of habitat have been listed as potential causal factors, but basic information on kestrel space use, including breeding home range size, is lacking. No study has provided robust estimates of the ranging behavior of breeding kestrels based on tracking data of any resolution. We fitted 19 adult female kestrels with solar-powered GPS transmitters during the incubation period in northern Virginia. High-resolution tracking began during the early nestling stage for 17 birds. We collected an average of 1710 locations per bird through the end of the breeding season (31 August), with 13 birds tracked through the fledging of their young. Autocorrelated kernel density home range estimation showed that female kestrels used breeding home ranges that were smaller (average: 0.32 km2) than most previously published range sizes. Home ranges did not vary significantly in size across breeding stages and demonstrated little overlap with the ranges of neighboring kestrels. Five females shifted their territories in the post-breeding stage (i.e., after disappearance or dispersal of fledglings) between 1.5 and 12.3 km from their nest box; they maintained these new ranges at least to the migration period. We also documented home range excursion forays (n = 128) by all 12 consistently tracked females. Mean (4.0 km) and maximum (127.7 km) foray distances were some of the largest reported among birds and mammals relative to home range size. Weekly foray rates were highest during the nestling stage, and for birds that ultimately shifted from their breeding home range. The existence of long-distance foray behavior and the use of multiple summer home ranges, both shown here for the first time for this species, has a direct impact on interpretation of kestrel nest-site and habitat selection data, and on the assessment of potential threats to this species in the breeding season.","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"135 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81713146","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}
{"title":"Trio of Aplomado Falcons Captures a Swallow-tailed Kite","authors":"Kennedy Borges, J. O. Coulson","doi":"10.3356/jrr-23-01","DOIUrl":"https://doi.org/10.3356/jrr-23-01","url":null,"abstract":"","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"27 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82646372","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}
Sandra Goded, Nathaniel N. D. Annorbah, O. Boissier, Kristen M. Rosamond, Samuel Boakye Yiadom, Zébigou Kolani, A. Mahama, N. Arcilla
Vultures are among the most threatened species in Africa, with several critically endangered species surviving mainly or only in protected areas. West African vulture declines are correlated with steep losses of natural habitat and mammalian wildlife. Major factors driving vulture extirpations include wildlife trade for traditional medicine, belief-based rituals, and bushmeat. Current data on vulture abundance and breeding ecology are crucial for conservation but lacking in many countries, including Ghana. Between 2020 and 2022, we conducted 761 km of surveys for critically endangered vultures in Mole National Park (Mole NP), a 4840 km2 protected savanna in northern Ghana. Using our count data, we estimated populations of 29–36 Hooded Vultures (Necrosyrtes monachus), 25–73 White-backed Vultures (Gyps africanus), and 3–4 White-headed Vultures (Trigonoceps occipitalis) in the southern region of Mole NP. We also documented 17 occupied vulture nests, including six Hooded Vulture nests, 10 White-backed Vulture nests, and one White-headed Vulture nest. Our findings include the first nest records for Hooded Vultures in Mole NP, the first nest description of White-backed Vultures in Ghana, and the first nest records for White-headed Vultures in Ghana, confirming the importance of Mole NP for conserving critically endangered vultures. Reducing poaching, preventing the killing of vultures for wildlife trade, and protecting vulture habitat and food resources will be paramount to the survival of critically endangered vultures in Ghana and West Africa.
{"title":"Abundance and Breeding Ecology of Critically Endangered Vultures in Mole National Park, Ghana","authors":"Sandra Goded, Nathaniel N. D. Annorbah, O. Boissier, Kristen M. Rosamond, Samuel Boakye Yiadom, Zébigou Kolani, A. Mahama, N. Arcilla","doi":"10.3356/jrr-22-54","DOIUrl":"https://doi.org/10.3356/jrr-22-54","url":null,"abstract":"\u0000 Vultures are among the most threatened species in Africa, with several critically endangered species surviving mainly or only in protected areas. West African vulture declines are correlated with steep losses of natural habitat and mammalian wildlife. Major factors driving vulture extirpations include wildlife trade for traditional medicine, belief-based rituals, and bushmeat. Current data on vulture abundance and breeding ecology are crucial for conservation but lacking in many countries, including Ghana. Between 2020 and 2022, we conducted 761 km of surveys for critically endangered vultures in Mole National Park (Mole NP), a 4840 km2 protected savanna in northern Ghana. Using our count data, we estimated populations of 29–36 Hooded Vultures (Necrosyrtes monachus), 25–73 White-backed Vultures (Gyps africanus), and 3–4 White-headed Vultures (Trigonoceps occipitalis) in the southern region of Mole NP. We also documented 17 occupied vulture nests, including six Hooded Vulture nests, 10 White-backed Vulture nests, and one White-headed Vulture nest. Our findings include the first nest records for Hooded Vultures in Mole NP, the first nest description of White-backed Vultures in Ghana, and the first nest records for White-headed Vultures in Ghana, confirming the importance of Mole NP for conserving critically endangered vultures. Reducing poaching, preventing the killing of vultures for wildlife trade, and protecting vulture habitat and food resources will be paramount to the survival of critically endangered vultures in Ghana and West Africa.","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"217 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86950075","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}
D. Bell, S. Snyder, Joseph E. Didonato, K. S. Smallwood
Assessing impacts of wind farms on volant animals requires conducting fatality monitoring studies that incorporate integrated carcass detection trials to account for searcher detection probability and carcass persistence and to reduce biases in the estimated number of fatalities (Smallwood et al. 2018). These trials involve placing a wide range of volant animal carcasses that mimic the expected species composition and actual spatial and temporal patterns of fatalities deposited by the wind turbines and measuring rates of carcass detection (Smallwood et al. 2018). When combined with remote cameras, carcass placement trials can reveal the suite of local scavengers that affect carcass persistence. We report here on an incident of conspecific carcass removal by a Great Horned Owl (Bubo virginianus) documented during a study designed to assess scavenger removal rates of avian carcasses at a wind energy project (Smallwood et al. 2009, 2010). We conducted the scavenger removal study from 12 December 2006 to 28 September 2007 on a 250ha parcel of land administered by the East Bay Regional Park District in the Altamont Pass Wind Resource Area, California, USA. The study area contained 52 functional wind turbines situated in rows along ridgelines within a landscape dominated by annual grasses. Sixty-three avian carcasses representing diverse avian species and body sizes, including two Great Horned Owls, were used for this study. Carcasses were obtained fresh-dead as either road kills or from animal rehabilitation hospitals and were kept frozen until used. To avoid scavenger swamping, from one to five carcasses were placed each week at randomly chosen locations within 60-m radii of wind turbine bases throughout the facility. Infrared, motion-activated cameras (Reconyxt, Holmen, WI, USA) were attached to metal posts approximately 1 m above the ground and 1.5 m away from each carcass. When activated, the cameras were set to take five pictures in rapid succession, with a recovery phase of approximately 1 sec between firings. All scavenging trial locations were monitored with cameras for 21 d after carcass placement or until a carcass was removed by scavengers, whichever came first. In some instances, camera removals were delayed beyond 21 d due to field conditions. After cameras were removed, all trial locations with either partial carcasses or feathers continued to be monitored weekly by biologists until the end of the study. For more details on this study, see Smallwood et al. (2009). A Great Horned Owl carcass was placed on 19 December 2006 at 1500 H in front of a remote camera set-up. On 13 January 2007, at 1843 H, a Great Horned Owl was photographed landing on
评估风电场对流浪动物的影响需要进行死亡率监测研究，其中包括综合尸体检测试验，以考虑搜索者发现概率和尸体持久性，并减少估计死亡人数的偏差(Smallwood et al. 2018)。这些试验包括放置各种挥发性动物尸体，模拟预期的物种组成和风力涡轮机沉积的实际死亡时空模式，并测量尸体检测率(Smallwood等人，2018)。当与远程摄像机相结合时，尸体放置试验可以揭示影响尸体持久性的当地食腐动物。我们在此报告了一项研究中记录的大角猫头鹰(Bubo virginianus)清除同种尸体的事件，该研究旨在评估风能项目中鸟类尸体的清除率(Smallwood et al. 2009, 2010)。我们于2006年12月12日至2007年9月28日在美国加利福尼亚州Altamont Pass风力资源区东湾地区公园区管理的一块250公顷的土地上进行了清除研究。研究区域包含52个功能风力涡轮机，沿山脊线排列，在一年生草为主的景观中。这项研究使用了63具鸟类尸体，代表了不同的鸟类种类和体型，其中包括两只大角猫头鹰。尸体是从新鲜的道路死亡或动物康复医院获得的，并冷冻保存直到使用。为了避免食腐动物淹没，每周将一到五具尸体随机放置在整个设施内风力涡轮机基地半径60米范围内的位置。红外运动激活摄像机(Reconyxt, Holmen, WI, USA)安装在距地面约1米，距每具尸体1.5米的金属柱子上。激活后，相机被设置为快速连续拍摄五张照片，每次拍摄之间的恢复阶段约为1秒。在屠体放置后或直至屠体被食腐动物移走之前，以先到者为准，用摄像机监测所有食腐动物试验地点21 d。在某些情况下，由于现场条件的原因，相机的移除被推迟到21天以后。在移除摄像机后，生物学家继续每周监测所有有部分尸体或羽毛的试验地点，直到研究结束。关于这项研究的更多细节，请参见Smallwood et al.(2009)。2006年12月19日下午15时，一只大角猫头鹰的尸体被放置在远程摄像机前。2007年1月13日，1843时，一只大角猫头鹰被拍到降落在
{"title":"Conspecific Carcass Removal from a Wind Project Study Plot by a Great Horned Owl (Bubo virginianus)","authors":"D. Bell, S. Snyder, Joseph E. Didonato, K. S. Smallwood","doi":"10.3356/JRR-21-65","DOIUrl":"https://doi.org/10.3356/JRR-21-65","url":null,"abstract":"Assessing impacts of wind farms on volant animals requires conducting fatality monitoring studies that incorporate integrated carcass detection trials to account for searcher detection probability and carcass persistence and to reduce biases in the estimated number of fatalities (Smallwood et al. 2018). These trials involve placing a wide range of volant animal carcasses that mimic the expected species composition and actual spatial and temporal patterns of fatalities deposited by the wind turbines and measuring rates of carcass detection (Smallwood et al. 2018). When combined with remote cameras, carcass placement trials can reveal the suite of local scavengers that affect carcass persistence. We report here on an incident of conspecific carcass removal by a Great Horned Owl (Bubo virginianus) documented during a study designed to assess scavenger removal rates of avian carcasses at a wind energy project (Smallwood et al. 2009, 2010). We conducted the scavenger removal study from 12 December 2006 to 28 September 2007 on a 250ha parcel of land administered by the East Bay Regional Park District in the Altamont Pass Wind Resource Area, California, USA. The study area contained 52 functional wind turbines situated in rows along ridgelines within a landscape dominated by annual grasses. Sixty-three avian carcasses representing diverse avian species and body sizes, including two Great Horned Owls, were used for this study. Carcasses were obtained fresh-dead as either road kills or from animal rehabilitation hospitals and were kept frozen until used. To avoid scavenger swamping, from one to five carcasses were placed each week at randomly chosen locations within 60-m radii of wind turbine bases throughout the facility. Infrared, motion-activated cameras (Reconyxt, Holmen, WI, USA) were attached to metal posts approximately 1 m above the ground and 1.5 m away from each carcass. When activated, the cameras were set to take five pictures in rapid succession, with a recovery phase of approximately 1 sec between firings. All scavenging trial locations were monitored with cameras for 21 d after carcass placement or until a carcass was removed by scavengers, whichever came first. In some instances, camera removals were delayed beyond 21 d due to field conditions. After cameras were removed, all trial locations with either partial carcasses or feathers continued to be monitored weekly by biologists until the end of the study. For more details on this study, see Smallwood et al. (2009). A Great Horned Owl carcass was placed on 19 December 2006 at 1500 H in front of a remote camera set-up. On 13 January 2007, at 1843 H, a Great Horned Owl was photographed landing on","PeriodicalId":16927,"journal":{"name":"Journal of Raptor Research","volume":"47 3 1","pages":"489 - 492"},"PeriodicalIF":1.7,"publicationDate":"2023-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84866319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：