Journal articles on the topic 'Raptors'
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1
Pratt, Mike. "Raptor Hacking." Wildlife Rehabilitation Bulletin 29, no. 1 (June 30, 2011): 34–38. http://dx.doi.org/10.53607/wrb.v29.78.
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In the raptor rehabilitation field, hacking is a special procedure for raising juvenile raptors that simulates natural fledging and allows young raptors—those that cannot yet fly and either are still restricted to or just leaving the nest—a gradual acclimation to independence. Hacking also is known as a ‘soft release.’ This paper focuses on hacking raptors and discusses advantages, disadvantages, hacking age, procedures, hack box design and construction, site selection, fledging age of raptor species, and hack release.
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BUIJ, RALPH, and BARBARA M. CROES. "Raptor habitat use in the Lake Chad Basin: insights into the effect of flood-plain transformation on Afrotropical and Palearctic raptors." Bird Conservation International 23, no. 2 (April 8, 2013): 199–213. http://dx.doi.org/10.1017/s0959270913000014.
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SummaryWest African flood-plains have undergone major land-use transformations in the second half of the 20th century. To obtain insight in the effect of flood-plain development for irrigated rice cultivation on the abundance, richness, and diversity of Palearctic and Afrotropical raptors, we conducted monthly transect surveys covering dry and wet seasons in four major habitats on the Waza-Logone flood-plain of Cameroon: dry grasslands, cultivated grasslands, rice fields, and seasonally flooded grasslands resembling natural flood-plain vegetation. We recorded 36 raptor species among 2,533 individuals, dominated by Black Kite Milvus migrans, which comprised 42% of counts. Although richness and diversity were not related to land-use for Palearctic raptors, Afrotropical raptor diversity was higher on the flooded grasslands compared to the newly created cultivated habitats and dry grasslands. The abundance of Afrotropical raptors did not significantly differ across habitats but was lower in rice-fields when Black Kite and Hooded Vulture Necrosyrtes monachus were excluded. Conversely, Palearctic raptor abundance was highest in post-harvest rice fields, demonstrating the importance of the rice fields as foraging habitat for Palearctic raptors. Further transformation of West Africa’s flood-plains is expected, reducing their capacity for Afrotropical raptors, while Palearctic raptors may benefit from expansion of rice-fields, but more research is needed on their vulnerability to pesticide use.
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Kumar, Sudesh, Asha Sohil, Muzaffar A. Kichloo, and Neeraj Sharma. "Landscape heterogeneity affects diurnal raptor communities in a sub-tropical region of northwestern Himalayas, India." PLOS ONE 17, no. 4 (April 28, 2022): e0246555. http://dx.doi.org/10.1371/journal.pone.0246555.
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Raptors are highly sensitive to environmental and human-induced changes. In addition, several species of raptors exist in considerably small numbers. It is thus critical to conserve raptors and their habitats across relatively larger landscapes. We examined the diurnal raptor assemblages and seasonality in a subtropical habitat in India’s northwestern Himalayas. Quantitative data on diurnal birds of prey and their habitat features across six distinct habitat types were collected from 33 sample sites. We observed 3,434 individuals of 28 diurnal raptors belonging to two orders and three families during a two-year survey from December 2016 to November 2018. A significant variation in bird species richness and abundance was found across habitats and seasons, with farmlands and winters being the most diverse and speciose. The generalized linear model, used to determine raptor community responses, indicated that elevation and proximity to dumping sites significantly affected the raptor abundance. The non-metric multidimensional scaling (NMDS) revealed significant differences in raptor assemblages across the habitat types. The study concluded that raptors’ persistence is largely determined by their preference for favourable feeding, roosting, and nesting opportunities. The presence of protected and habitat-exclusive species validates the high conservation importance of these ecosystems, particularly the forest patches and farmlands, necessitating robust conservation and management measures in this part of northwestern Himalaya.
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Fitzsimons, James A., and Jack Leighton. "Frugivory in Raptors: New Observations from Australia and a Global Review." Birds 2, no. 4 (October 19, 2021): 338–50. http://dx.doi.org/10.3390/birds2040025.
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The diets of raptors are some of the best studied and well-known of all bird groups. Raptors are typically carnivores, hunting and feeding on vertebrates and, for some species, invertebrates. Here, we described instances of the Black Kite (Milvus migrans) and Whistling Kite (Haliastur sphenurus) consuming non-native avocado (Persea americana) fruit in commercial orchards in northern Australia, over multiple years. This appears to be the first instance of frugivory by raptors in Australia. We review instances of frugivory for other raptor species globally. This review finds that 29 species of raptor from the families Falconidae, Accipitridae and Cathartidae have been recorded consuming fruit, significantly more than previous reviews.
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Jurisevic, Mark A., and Ken J. Sanderson. "Acoustic discrimination of passerine anti-predator signals by Australian raptors." Australian Journal of Zoology 46, no. 4 (1998): 369. http://dx.doi.org/10.1071/zo97052.
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Acoustic discrimination of anti-predator calls was examined in 11 species of Australian raptors, including 5 Falco species and 2 species of Elanus kites, by their responses to the playback of alarm and distress calls of Australian passerines. The present study investigated the ability of raptors to discriminate between alarm and distress calls that have different acoustic properties and are emitted in different behavioural contexts. The raptors were tested with broad-band calls (containing a wide range of frequencies) given as distress calls, mobbing calls and alarm calls to terrestrial predators, and with narrow-band calls (comprising a narrow range of frequencies) typically given as a response to flying predators. Raptor responses were categorised into three classes based on head orientation (or lack thereof) towards the sound source (i.e. one of 2 or 4 speakers positioned in the cage set-up); (1) ‘correct response’ – the raptor looked directly at the speaker; (2) ‘incorrect response’ – the raptor detected the sound, but oriented the head in a direction other than towards the sound source; (3) ‘no response’. All raptor species showed a higher percentage of correct responses (60–100%) for broad-frequency vocalisations and a lower percentage of correct responses (usually 0–40%) and more incorrect responses for narrow-band vocalisations. Further, all raptors showed a greater rate of overall responsiveness to broad-band alarm and distress calls than narrow-band calls, indicating a higher interest level in the former. The behavioural implications of acoustic discrimination by Australian raptors to different types of alarm call are discussed.
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Ringim, Abubakar S., Samuel T. Ivande, Sulaiman I. Muhammad, Paul T. Apeverga, and Harry Hanson Jr. "Only one vulture was detected during transect surveys in northern Nigeria." Vulture News 82 (September 13, 2022): 14–22. http://dx.doi.org/10.4314/vulnew.v82i1.2.
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Vulture and raptor populations have declined across West Africa during recent decades due to numerous and widespread anthropogenic threats. To estimate encounter rates of vultures and raptors in northern Nigeria, we conducted a total of 248 km driven transects on 195 km and 53 km of paved and unpaved roads, respectively. We also conducted walked surveys beneath 79 km of power transmission lines to search for dead vultures and raptors; and visited 12 abattoirs, 11 slaughterhouses, and 12 dumpsites to assess the occurrence of vultures and raptors. All fieldwork was done between October and December 2018. Overall, 357 individuals of 23 species were detected, most of which were recorded at low encounter rates. Only one Hooded Vulture Necrosyrtes monachus was recorded across all surveys, and no other vulture species were seen. Yellow-billed Kite Milvus aegyptius, Grasshopper Buzzard Butastur rufipennis, and Black-winged Kite Elanus caeruleus had the highest encounter rates of 0.351, 0.262, and 0.189 individuals km-1, respectively. In contrast, the largest raptor species, Booted Eagle Hieraaetus pennatus, Short-toed Snake Eagle Circaetus gallicus, Beaudouin's Snake-eagle, and Bateleur Terathopius ecaudatus had the lowest encounter rate of 0.004 individuals km-1 (one individual each). No dead vultures or raptors were found during the walked surveys beneath power lines. Although historical data about vulture and raptor distribution and abundance in northern Nigeria are limited, our results show an apparent absence of vultures from the wider landscape and a low density of raptors. Support among local stakeholders for the conservation of vultures and raptors should be encouraged through wider dissemination of information about the importance of these birds, as well as stronger deterrents again illegal killing and trade.
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Giry Xavira Putri, Bambang Agus Suripto, and Asman Adi Purwanto. "Keanekaragaman dan Kemelimpahan Burung Pemangsa (Raptor) Migran di Kawasan Bukit 76 Kaliurang, Yogyakarta." Biotropic : The Journal of Tropical Biology 5, no. 1 (February 27, 2021): 1–8. http://dx.doi.org/10.29080/biotropic.2021.5.1.1-8.
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Migratory birds are birds that fly or move from their breeding place to their non-breeding location. Migratory birds usually migrate to the southern part of the earth or tropical regions to avoid limited resources during winter in their breeding areas (Bildstein, 2006). Bird of Prey or Raptors are a group of birds that frequently migrate. Raptors carry out-migration in several areas which are commonly referred to as flyways. Indonesia is also part of the flight path for migratory birds (Sukmantoro et al., 2007). At this time there were approximately 17 types of migrant raptors in Indonesia. Research on raptor migration has been carried out for a long time in various regions. In the Yogyakarta area, there have been observations of a migrant raptor, but there are no official publications and research on migrant raptor in the Bukit 76 Kaliurang area, Yogyakarta. Therefore this research was conducted to know about migratory raptor in Yogyakarta. This research was conducted at Bukit 76 Kaliurang, Hargobinangun, Pakem, Yogyakarta. The research was conducted in December 2019-March 2020, July-August 2020, and October-November 2020. This research was conductes through observations in the morning at 07.00-11.00 WIB using birdwatching techniques and purposive methods. The results of this study recorded 1 species of migrant raptor, namely the Oriental Honey-buzzard (Pernis ptilorhynchus) and 2 species of resident raptors, namely the Crested Serpent Eagle (Spilornis cheela) and the Brahminy Kite (Haliastur indus).
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Hockett, Bryan Scott. "Archaeological Significance of Rabbit-Raptor Interactions in Southern California." North American Archaeologist 10, no. 2 (October 1989): 123–39. http://dx.doi.org/10.2190/vpyb-e14b-fyx9-xapa.
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Taphonomy of small fauna is not as well known as actualistic studies performed with large faunal remains. Yet small fauna like rabbit may dominate an archaeological assemblage. Small fauna was a primary meat source for many prehistoric groups in North America. Raptors also damage and disperse rabbit bones. Taphonomic research with rabbit-raptor interactions was undertaken in a lacustrine environment in southern California to determine the role played by raptors in damaging and dispersing rabbit bones which may subsequently be introduced into archaeological sites. Raptors often damage, disperse, and accumulate rabbit bones in a number of areas, including open-air localities and within abandoned human structures. Potential diagnostic characteristics of rabbit bones damaged by raptors are offered as baseline end-effects of raptors exploiting rabbit carcasses. Archaeologists can compare rabbit bones excavated from archaeological sites to these bones known to be damaged by raptors. This information is crucial to archaeologists for accurately interpreting rabbit bones modified by human action, and thus past subsistence strategies over time.
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Nourani, Elham, Kamran Safi, Noriyuki M. Yamaguchi, and Hiroyoshi Higuchi. "Raptor migration in an oceanic flyway: wind and geography shape the migratory route of grey-faced buzzards in East Asia." Royal Society Open Science 5, no. 3 (March 2018): 171555. http://dx.doi.org/10.1098/rsos.171555.
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Flapping flight is relatively costly for soaring birds such as raptors. To avoid costly flight, migrating raptors generally avoid flying over water. As a result, all but one of the global raptor migration flyways are largely over land. The East Asian oceanic flyway for raptors is the exception. Raptor species using this flyway migrate by island-hopping, flying over open ocean for distances of up to 300 km between islands. We used satellite telemetry data for grey-faced buzzards Butastur indicus , a species that dominates the southern part of the flyway, to investigate the geographical and atmospheric factors responsible for the suitability of this flyway for raptor migration. Using a combination of least-cost path analysis and a step selection function, we found that the occurrence of numerous islands and also suitable wind support along the oceanic flyway are responsible for route selection in grey-faced buzzards. These results confirm the role of islands, but also wind, in shaping the East Asian oceanic flyway of long-distance raptor migration.
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Denac, Katarina. "Census of migrating raptors at Breginjski Stol (NW Slovenia) - the first confirmed bottleneck site in Slovenia." Acrocephalus 31, no. 145-146 (January 1, 2010): 77–92. http://dx.doi.org/10.2478/v10100-010-0005-6.
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Census of migrating raptors at Breginjski Stol (NW Slovenia) - the first confirmed bottleneck site in Slovenia From 4 to 31 May 2010, raptor migration was monitored daily between 9.00 and 17.00 hrs CET at Breginjski Stol (NW Slovenia). In all, 2,385 raptor passes were counted, belonging to at least 17 species that were divided into resident and migratory birds. Residents (n = 875 passes) foraged, bred or daily migrated over the area. Among them, Griffon Vulture Gyps fulvus was the most frequent species (n = 575 passes) with the largest observed group of 35 individuals on 26 May. In the morning, Griffon Vultures were flying from west to east in search of food, whereas in the afternoon they were returning in the opposite direction to their colony in Forgaria nel Friuli (Italy). Their numbers increased after 15 May, when Croatian Griffons joined those from Italy. Altogether, 1,510 individuals of migratory raptors were counted, belonging to at least nine species. Among them, Honey Buzzard Pernis apivorus was the most common (1,368 ind., 90.6% of migratory raptors). The migration peak was reached on 14 May, with 552 individuals. Most raptors were seen migrating solitarily or in small flocks (2-4 ind.), whereas on five days (4, 7, 11, 13, 14 May) over 20% of all observed flocks were either medium-sized (5-15 ind.) or large (> 15 ind.). Raptors mostly migrated between 9.00 and 13.00 hrs. Taking into consideration several factors - short observation period and limited number of observation hours per day, overlooked raptors due to human- and topography-related causes, movements of observers between observation points, extremely bad weather and night migration of raptors - we estimate that the actual number of migratory raptors that passed Breginjski Stol in spring 2010 was 3,060-4,660 individuals. Thus, Breginjski Stol is the first confirmed bottleneck site of European importance for migratory raptors in Slovenia, as defined by BirdLife International IBA criterion B1iv, and a natural continuation of migratory pathways from northern Italy.
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Baril, Lisa M., David B. Haines, Lauren E. Walker, and Douglas W. Smith. "Autumn Raptor Migration in Yellowstone National Park, 2011–2015." Canadian Field-Naturalist 131, no. 4 (May 23, 2018): 303–11. http://dx.doi.org/10.22621/cfn.v131i4.1909.
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Raptors are wide-ranging, vagile avian predators whose populations can be difficult and costly to monitor on their breeding or winter range. However, monitoring raptors during their annual northbound or southbound migration is a cost-effective and efficient alternative to time-intensive, single-species breeding surveys. In 2010, we observed numerous Swainson’s Hawks (Buteo swainsoni) and Red-tailed Hawks (Buteo jamaicensis) migrating through the Hayden Valley in central Yellowstone National Park, prompting an investigation into raptor migration patterns in the park. Our objectives were to monitor annual autumn raptor migration in Hayden Valley from 2011 to 2015 and to determine the relative role of this undocumented migration site by comparing our observations to simultaneously collected migration data from three other sites in the Rocky Mountain Flyway. From 2011 to 2015, we observed 6441 raptors of 17 species across 170 d and 907 h of observation. Red-tailed Hawks, Swainson’s Hawks, and Golden Eagles (Aquila chrysaetos) accounted for 51% of the total individuals observed over five years. Overall counts from Hayden Valley were comparable to counts from the three migration sites in the Rocky Mountains, although abundance of individual species varied by site. Data from this study suggest that Hayden Valley may serve as a stopover site for migrating raptors and presents an opportunity for future research. By improving our understanding of where raptors migrate and the characteristics of stopover areas in the Rocky Mountains, land managers may develop effective strategies for protecting raptor populations and habitat from threats including development and climate change.
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Han, Chun-Hua, Jian Lin, Xiuqing Wang, Jing-Wen Han, Hui-Juan Duan, Jie Pan, and Yue-Huan Liu. "Sialic acid profiles in the respiratory tracts of selected species of raptors: evidence for potential binding sites for human and avian influenza A viruses." Wildlife Research 38, no. 8 (2011): 647. http://dx.doi.org/10.1071/wr11003.
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Context The ability of influenza A viruses to recognise and bind to cell surface receptors such as sialic acid linked to galactose by an α2,3 linkage (SAα2,3-gal) and sialic acid linked to galactose by an α2,6 linkage (SAα2,6-gal) is a major determinant of influenza A virus infection. Although the epidemiological surveys of influenza A virus infection in raptors suggest that some raptor species are susceptible to influenza A viruses under natural conditions, the sialic acid profiles in the respiratory and intestinal tracts of raptors are unknown. Aims To examine the sialic acid receptor profiles in the respiratory tracts of the selected raptor species and assess the potential susceptibility of raptors to avian and human influenza viruses and the role of raptors in the epidemiology and evolution of influenza A viruses. Methods The lectin immunohistochemistry staining method was used to examine the sialic acid profiles in the respiratory tracts of eight different species of raptors. Key results A strong staining with Maackia amurensis agglutinin (MAA), specific for sialic acid linked to galactose by an α2,3 linkage (SAα2,3-gal), was observed in the epithelial cells of the respiratory tract of Accipiter nisus and Falco tinnunculus. However, a positive staining for both MAA and Sambucus nigra agglutinin (SNA), specific for sialic acid linked to galactose by an α2,6 linkage (SAα2,6-gal), was detected in the epithelial cells of the upper respiratory tract of Accipiter gularis, Buteo buteo, Otus sunia, Bubo bubo and Asio otus, and in the epithelial cells of the alveoli of Buteo buteo, Falco peregrinus, Otus sunia and Bubo bubo. Conclusions Both avian and human influenza A virus receptors are expressed in six species of raptors examined. There are some variations in the type and distribution of sialic acid receptor expression among different raptor species. No correlation between phylogeny of birds and their sialic acid receptor distributions was observed. Implications Since SAα2,3-gal and SAα2,6-gal are often considered as the primary receptors for avian influenza A viruses and human influenza A viruses, respectively, our data suggest that raptors could be a potential host for avian and human influenza A viruses.
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Espín, Silvia, Jovan Andevski, Guy Duke, Igor Eulaers, Pilar Gómez-Ramírez, Gunnar Thor Hallgrimsson, Björn Helander, et al. "A schematic sampling protocol for contaminant monitoring in raptors." Ambio 50, no. 1 (May 12, 2020): 95–100. http://dx.doi.org/10.1007/s13280-020-01341-9.
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AbstractBirds of prey, owls and falcons are widely used as sentinel species in raptor biomonitoring programmes. A major current challenge is to facilitate large-scale biomonitoring by coordinating contaminant monitoring activities and by building capacity across countries. This requires sharing, dissemination and adoption of best practices addressed by the Networking Programme Research and Monitoring for and with Raptors in Europe (EURAPMON) and now being advanced by the ongoing international COST Action European Raptor Biomonitoring Facility. The present perspective introduces a schematic sampling protocol for contaminant monitoring in raptors. We provide guidance on sample collection with a view to increasing sampling capacity across countries, ensuring appropriate quality of samples and facilitating harmonization of procedures to maximize the reliability, comparability and interoperability of data. The here presented protocol can be used by professionals and volunteers as a standard guide to ensure harmonised sampling methods for contaminant monitoring in raptors.
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Vrezec, Al, Guy Duke, András Kovács, Pertti Saurola, Chris Wernham, Ian Burfield, Paola Movalli, and Irena Bertoncelj. "Overview of raptor monitoring activities in Europe." Acrocephalus 33, no. 154-155 (December 1, 2012): 145–57. http://dx.doi.org/10.2478/v10100-012-0003-y.
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Abstract Despite the key role of raptors (including birds of prey Falconiformes and owls Strigiformes) in ecosystems and their sensitivity to environmental change, a well coordinated, Europe-wide monitoring of raptors is lacking. EURAPMON, a Research Networking Programme of the European Science Foundation, was launched with the aim of establishing a sustainable Europewide network for monitoring of raptors. An overview of current monitoring schemes for raptor populations in 28 European countries, as reported by EURAPMON National Coordinators at the workshop in Murcia (Spain) in 2012, showed existing monitoring schemes to be limited to a restricted number of species (mostly diurnal and rare raptor species). The most widely monitored species are the Golden Eagle Aquila chrysaetos amongst diurnal raptors and the Eagle Owl Bubo bubo amongst owls. Broad coverage of a species range across Europe is reached only for restricted-range species. The key driver for monitoring, which is mostly coordinated by NGOs, is conservation, and the main end users are governmental institutions. International collaboration in the field of monitoring of raptors is mainly regional and not yet pan-European in scale. The involvement of volunteers in raptor monitoring was perceived as the main strength of many schemes, but insufficient manpower and a focus on rare species were recognised as the main weaknesses across Europe as a whole. Among priorities identified for the future development of monitoring schemes are: improvements to national coordination; support to increase the number of volunteers; and assurances of stable funding. Further analysis of EURAPMON questionnaires will identify knowledge gaps, which will steer good practice guidance on survey methodologies; the need for the latter was identified as the main benefit that National Coordinators expect to gain from international networking
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Moore, Adele. "Principles of Raptor Cage Design." Wildlife Rehabilitation Bulletin 32, no. 1 (June 30, 2014): 12–16. http://dx.doi.org/10.53607/wrb.v32.23.
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Constructing a cage for raptors in rehabilitation requires planning to ensure the cage will have all the components required for training raptors and for a successful release back into the wild. The author explores a checklist of what is needed both in the planning and in the construction stages. TreeHouse just designed and completed a Raptor Rehabilitation Complex in which all the cage elements are under one roof and flexible.
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Gao, Kai, Bing Zhou, Li-Xing Yang, Lu Dong, Xi Huang, and Wen-Hong Deng. "How Does Circadian Rhythm Shape Host-Parasite Associations? A Comparative Study on Infection Patterns in Diurnal and Nocturnal Raptors." Diversity 13, no. 8 (July 23, 2021): 338. http://dx.doi.org/10.3390/d13080338.
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Infection patterns of parasites, including their prevalence, diversity and host specificity, can be impacted by many biological and environmental factors, but no study has focused on the circadian rhythms of vertebrate hosts, which may affect susceptibilities and encounter rates between hosts and vectors and further shape host-parasite associations. In this study, we focused on avian haemosporidians, a classical model in studies of host-parasite associations, and investigated the infection patterns in rescued raptors brought to the Beijing Raptor Rescue Center during 2007–2020. We first assessed the association between prevalence and host biotic traits; haemosporidian prevalence was higher in the nocturnal raptors than in the diurnal raptors, and the prevalence of Haemoproteus and Leucocytozoon in the nocturnal raptors was significantly higher than that in the diurnal raptors. Furthermore, we analysed the phylogenetic relationship and host-parasite network-level differences of haemosporidian parasites in diurnal and nocturnal raptors, and demonstrated that the lineages infecting the diurnal and nocturnal raptors were not clearly separated, but the nocturnal lifestyle led to a more specialized host-parasite network structure. These variations in host-parasite associations may be driven by different susceptibilities of the hosts and the diversity or abundance of vectors during the day and night. Our study provides new insight into host-parasite associations shaped by circadian rhythm and calls for more studies on the underlying mechanisms of parasite infection.
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Viteri, Maria C., Mary Allison Stegner, and Elizabeth A. Hadly. "Assessing the reliability of raptor pellets in recording local small mammal diversity." Quaternary Research 106 (October 21, 2021): 1–10. http://dx.doi.org/10.1017/qua.2021.59.
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AbstractUnderstanding how raptors select prey is important to determine taphonomic biases both in modern and paleo pellet assemblages. We tested whether pellets more closely represent raptor dietary specialization or local small mammal diversity by sampling pellets from seven raptor species across four study sites in Yellowstone National Park, Wyoming, USA. We identified small mammal craniodental elements from each pellet and tested for differences among small mammal assemblages for each raptor species and study site. We found that reconstructed avian predator diets clustered significantly by site but not by predator species. Bray-Curtis diet dissimilarities were also significantly lower when comparing different raptor species within a site than when comparing the same raptor species across different sites. Our results suggest that raptors choose to eat a diversity of small mammal species close to their roosts rather than fly long distances to specialize on a particular prey species. Neontologists and paleoecologists alike can therefore be confident that raptor pellets faithfully represent local small mammal diversity.
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Gunawan, Fajar Aji D.N, Tauhid Nursalim, Danafia Permana, and Susanti Withaningsih. "Comparative Study of Released Javan Hawk-Eagle (Nisaetus bartelsi) And Changeable Hawk-Eagle (Nisaetus cirrhatus) Based On Satellite Tracker Data." E3S Web of Conferences 249 (2021): 03002. http://dx.doi.org/10.1051/e3sconf/202124903002.
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The release of a rehabilitated raptor, defined as an effort to release the raptor back into nature, have been done in Indonesia; however, only about 2% were monitored for more than one year. This is because long time intensive monitoring using simple observation equipment is difficult to do because of limited resources. Thus, more modern equipment – oneof which is satellite radio used in this research – needs to be used. The use of satellite radio to monitor the movement of rehabilitated raptors was carried out for the first time in 2018 for juvenile male Javan hawk-eagles (N.bartelsi) and adult female Changeable hawk-eagles (N.cirrhatus). The results of the monitoring of these two types of raptors showed that they mostly used forested areas close to water sources. Both types of eagles had the farthest flight distance with an average distance of ± 1,000 m / day occurring at week 4. Thus, it can be concluded that the rehabilitation efforts for these eagles were successful and that they had adapted to their new habitats as wild raptors.
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Rodrigues, Patrícia, Marco Mirinha, and Luís Palma. "Diurnal raptors of West Africa woodland-farmland mosaics: Data from walking-transects in eastern Guinea-Bissau." Avian Biology Research 13, no. 1-2 (February 12, 2020): 18–23. http://dx.doi.org/10.1177/1758155920901424.
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Guinea-Bissau is a small country in West Africa, which in spite of its rich biodiversity and the high proportion of protected areas remains under-surveyed in relation to most animal groups, including raptors. The first scientific articles about raptors were only very recently issued. Here, we report raptor occurrence data from eastern Guinea-Bissau. Raptors were surveyed in the dry season along transects walked around 21 villages in a rural woodland-farmland mosaic landscape. The raptor assemblage is composed of 25 species of which the hooded vulture, the lizard buzzard and the African harrier-hawk were the species more often encountered, followed by the African white-backed vulture. The palm-nut vulture, black kite, brown snake-eagle, grasshopper buzzard, African hawk-eagle, grey kestrel and lanner falcon were secondary, although not uncommon species. The remaining species were seldom recorded. The study complements previous knowledge on this bird group, specifically in the central-eastern part of the country, and reaffirms the international relevance of Guinea-Bissau for the conservation of the hooded and African white-backed vultures.
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Saurola, Pertti. "An overview of monitoring for raptors in Finland." Acrocephalus 33, no. 154-155 (December 1, 2012): 203–15. http://dx.doi.org/10.2478/v10100-012-0007-7.
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Abstract In Finland, population monitoring for both diurnal and nocturnal raptors has been almost entirely based on fieldwork carried out by voluntary raptor ringers. Responsible organisations include the Finnish Museum of Natural History, with economic support for administration from the Ministry of Environment, “Metsahallitus” (former National Board of Forestry) and WWF Finland. Since the early 1970s, numbers and productivity of four endangered species, the White-tailed Eagle Haliaeetus albicilla, Golden Eagle Aquila chrysaetos, Osprey Pandion haliaetus and Peregrine Falcon Falco peregrinus have been monitored by country-wide Comprehensive Surveys, with the aim of checking all known nest sites of these species every year. The Gyrfalcon F. rusticolus was included in this group in the late 1990s. Data for monitoring the populations of the other raptor species have been gathered by the Raptor Grid and Raptor Questionnaire projects. The Raptor Grid project produces annual population indices, which are calculated from the data collected from 10 × 10 km study plots (n = ca. 130/year) and quite well reflect the annual population fluctuations and longterm trends of seven common species of diurnal and six species of nocturnal raptors breeding in the southern part of Finland. For the rest of the species, which are either rare all over Finland or breed mostly in the north, outside the good coverage of the distribution of Raptor Grid study plots, conclusions on population changes are based on the total numbers of occupied territories and active nests reported annually by the Raptor Questionnaires
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Spasov, Svetoslav, Volen Arkumarev, Dobromir Dobrev, and Vladimir Dobrev. "An overview of monitoring for raptors in Bulgaria." Acrocephalus 33, no. 154-155 (December 1, 2012): 181–89. http://dx.doi.org/10.2478/v10100-012-0005-9.
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Abstract Since 1990, nature conservation NGOs are the main players in the running of nation-wide research and monitoring schemes for raptors in Bulgaria. Among them, the Bulgarian Society for the Protection of Birds (BSPB) and Green Balkans are most active, covering the most threatened diurnal raptors in the country. The key species covered by comprehensive monitoring schemes are the Imperial Eagle Aquila heliaca, White-tailed Eagle Haliaeetus albicilla, Egyptian Vulture Neophron percnopterus, Griffon Vulture Gyps fulvus, Black Vulture Aegypius monachus, Saker Falcon Falco cherrug and Red-footed Falcon F. vespertinus. Information on their distribution, numbers, breeding success, productivity, diet, movements etc. is gathered on annual basis. The Buzzard Buteo buteo and Kestrel F. tinnunculus are also regularly monitored at the national level by the Common Bird Monitoring scheme. Distribution of all raptor species has been studied for the purpose of the Atlas of Breeding Birds in Bulgaria. The contemporary satellite telemetry methods revealed important aspects of movements and threats to eagles and vultures from Bulgaria within the country and abroad. Main threats for the raptors in Bulgaria are related to habitat loss, unnatural mortality and disturbance. The main gaps in raptor monitoring in Bulgaria are related to the lack of coverage of most of the diurnal species and owls. There is a strong national and international cooperation in conjunction with the work concerning Imperial Eagle, Egyptian and Griffon Vultures. However, further enhancement of cooperation on other raptor species and issues such as lobbying for implementation of raptor-friendly agricultural practices and enhancement of various economic sectors are needed
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Rossi, Giacomo, Giuliana Terracciano, Riccardo Gherardi, Livio Galosi, and Stefania Perrucci. "Parasites, Bacteria, and Associated Pathological Changes in the Digestive System of Diurnal and Nocturnal Raptors in Central Italy." Pathogens 10, no. 12 (November 30, 2021): 1567. http://dx.doi.org/10.3390/pathogens10121567.
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The knowledge of raptor pathogens and associated lesions may be extremely important to enhancing raptor conservation efforts and reducing pathogen spillover to humans and domesticated animals and vice versa. Parasite infections of the digestive system and associated bacteria and pathological changes were evaluated in deceased diurnal and nocturnal raptors in central Italy. Overall, the prevalence of parasites (nematodes, cestodes, trematodes, acanthocephalans, and protozoa) identified in the examined birds was 72.41%, and most of the positive raptors (71.42%) showed multiple parasite infections. Among bacteria, Salmonella typhimurium, Salmonella enterica subspecies diarizonae, Escherichia coli, Clostridium perfringens, Yersinia enterocolitica, and Pasteurella multocida were identified. The results obtained showed that both parasites and bacteria may cause severe lesions in the digestive system of diurnal and nocturnal raptors; parasites and bacteria may concur in causing these lesions; most severe lesions are caused by the interaction of multiple pathogens, both parasites and bacteria; and the same pathogen taxa are frequently associated with the same pathological changes. This study is the first report of S. typhimurium and S. enterica subspecies diarizonae in Buteo buteo, while Andracantha mergi, Spirocerca spp., Sarcocystis dispersa, Sarcocystis columbae, and Eumonospora spp. were recorded for the first time in Italy.
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Hille, Sabine M., and Nigel J. Collar. "Status assessment of raptors in Cape Verde confirms a major crisis for scavengers." Oryx 45, no. 2 (April 2011): 217–24. http://dx.doi.org/10.1017/s0030605310000682.
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AbstractScavenging raptors have been postulated to be declining at a rate far higher than predatory raptors. To test this hypothesis we reviewed the historical and present status of the seven raptor species—three scavengers (two kites and a vulture), one partial scavenger (a buzzard) and three species (osprey and two falcons) that take live prey—that breed on the Cape Verde islands. Scavenging raptors have experienced steeper declines and more local extinctions than non-scavengers in Cape Verde, with the partial scavenger midway between the two groups. Causes of scavenger decline include incidental poisoning, direct persecution and declines in the availability of carcasses and other detritus. These findings, which highlight the conservation importance of the island of Santo Antão, indicate the priority that needs to be accorded to scavengers, particularly in Europe where many insular populations are reaching unsustainable levels.
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Carneiro, Manuela, Bruno Colaço, Jorge Colaço, Ana I. Faustino-Rocha, Aura Colaço, Santiago Lavin, and Paula A. Oliveira. "Biomonitoring of metals and metalloids with raptors from Portugal and Spain: a review." Environmental Reviews 24, no. 1 (March 2016): 63–83. http://dx.doi.org/10.1139/er-2015-0051.
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The analysis of metals in different tissues of raptors has been an important tool for assessing metal pollution. Several studies using a range of sentinel raptor species have been carried out in Portugal and Spain since the 1980s to identify the adverse effects in the animals themselves and on their populations, to identify the contamination of the food chain, to determine the levels of environmental contamination and to estimate human health risks. The aim of this work is to provide synthesized information of the studies carried out in Portugal and Spain in the direct biomonitoring of metals and metalloids using raptors, through a systematic search of the published literature. The information is summarized taking into account specific issues, such as monitored raptor species, sampling periods, monitored areas, type of samples, analytical techniques used in the determination of the metals and metalloids, the analysed metals and metalloids, and overall analysis of the concentrations obtained. There is a striking difference between the number of studies performed in Portugal and Spain, and most of them have been carried out in Spain. The eagle owl, black kite, and common buzzard were the species from which the greatest number of individuals have been analysed. Among the most analyzed biological samples, the blood and liver samples were used to measure the concentrations of all studied metals, while bone was mainly collected to evaluate chronic exposure to lead and feathers to evaluate exposure to mercury during feather growth. Atomic absorption spectrometry has been the most frequently performed technique to determine the majority of metals and arsenic. In general, the concentrations of metals detected in raptor samples from Portugal and Spain are low and insufficient to produce toxic side effects. Only lead, in certain cases, can be related with toxic side effects. However, particular attention should be given to mercury due to its high toxicity, its transport from an aquatic environment to the adjacent terrestrial food web, and because the mercury toxicity threshold has yet to be established for raptors. This work confirms the need for further biomonitoring studies of metals with raptors, especially in Portugal; the establishing of national programs to conduct long-term studies; and creating a network between Portugal and Spain to study environmental contamination using raptors.
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Karakaș, Recep. "Current status and distribution of diurnal raptor species in the south-eastern Anatolia Region, Turkey." Slovak Raptor Journal 9, no. 1 (June 30, 2015): 105–13. http://dx.doi.org/10.1515/srj-2015-0008.
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Abstract The status and distribution of diurnal raptor bird species were analysed in the south-eastern part of Turkey based on studies and records between 1994 and 2014. Our information about raptor species is very limited in the south-eastern Anatolia Region. The study showed that of 42 diurnal raptor species listed in Turkey, 37 of these species were found in the studied region; 9 of them are certainly, 4 probably and 1 possibly breeding in the area - according to the breeding criteria of the EBCC - while 17 of them were transitory migrating or wintering birds for the region, and the breeding/migratory status of 6 is unknown. Habitats lost and fragmentation related to agricultural intensification together with pesticide applications are the main hazards threatening wildlife including raptors in the region. So as to increase knowledge on raptors in south-eastern Anatolia and evaluate their populations, a coordinated education and research program is essential.
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Elafri, Ali, Okba Boumaaza, Mohamed Dhaya El-Hak Khemis, Khieredin Boucherit, and Moussa Houhamdi. "Population Dynamics and Distribution Patterns of Diurnal Raptors in Northeastern Algeria: Seasonal Variation and Some Nesting Characteristics." Ekológia (Bratislava) 39, no. 1 (March 1, 2020): 58–71. http://dx.doi.org/10.2478/eko-2020-0005.
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AbstractProviding a live data monitoring of raptor abundances and spatial localization of their most important nesting areas is very helpful in building a strong future study and applying a sound strategy for effective safeguarding of these emblematic species. Using geographic information system (GIS) and global positioning system (GPS) techniques, we investigated spatial patterns of raptors distribution in the northeastern areas of Algeria during two consecutive breeding seasons (2014 and 2015). The total area sampled (31,000 km2) host diverse raptor species (14 species), among them, the threatened species Egyptian vulture (Neophron percnopterus; 108 individuals and 19 active nests) and red-footed falcon (Falco vespertinus; 12individuals). The value of the region is attested by the presence of an abundant population of nesting black kite (Milvus migrans; 337 individuals). The large-scale spatial analyses of the studied region illustrate certain similarities in nesting habitat selection among raptors. Almost all species (90% of 209 nests detected) preferred to nest within multispecies assemblages (20 raptor assemblages found) and occupied altitudinal rocky cliffs across the inland region (semi-arid zones) rather than coastal region (sub-humid zones). Among all raptor species, exclusively, the common kestrel (Falco tinnunculus) is relatively synanthropic, because it was found to breed within cities (tolerate human activities). The raptor community in the coastal versus inland regions differed by 14%. The latter area seems to be more preferred in nest building, probably consequence of their semi-arid bioclimatic and landscapes characteristics, where high elevations and grasslands forming mosaics with Oak, Alpine, and Cedar forests are patchily distributed. The study is a first mapping database of important nesting sites dispatched across the northeastern areas of Algeria, and it can be effectively used in future complementary researches that aim to elucidate environmental factors that affect raptors life cycle.
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Leveau, Lucas M. "The Harris Hawk (Parabuteo unicinctus) in Urban Areas of Argentina: Arrival in Mar Del Plata City and Green Area Use in Buenos Aires City." Animals 11, no. 4 (April 5, 2021): 1023. http://dx.doi.org/10.3390/ani11041023.
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Urbanization has a negative impact on raptor species diversity and abundance. However, some species can adapt to urban areas, and the process of city colonization by raptors has been documented scarcely in the Northern Hemisphere. Information about city colonization by raptors in the Southern Hemisphere is null, and studies about habitat use by raptors are scarce. The objectives of this study were: (1) to describe an event of Harris Hawk (Parabuteo unicinctus) arrival in Mar del Plata city, Argentina, and (2) to analyze its green area use in a recently colonized city, Buenos Aires. Long-term data collected during 2002–2019, along an urbanization gradient of Mar del Plata, was used to describe the city arrival by the Harris Hawk. Surveys of green areas in Buenos Aires were used to model the Harris Hawk occurrence in relation to green area size and isolation to other green spaces. The Harris Hawk arrival was observed during 2019, mainly in periurban areas of Mar del Plata, and at least three pairs were breeding. In Buenos Aires, the occurrence of the Harris Hawk in green areas was related to the proximity to other large green areas. The results obtained suggest the importance of green areas for raptor colonization in cities.
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Hadad, Ezra, Piotr Zduniak, and Reuven Yosef. "Sustaining Increasing Wintering Raptor Populations in Central Israel: A 38 Years Perspective." Sustainability 14, no. 19 (September 30, 2022): 12481. http://dx.doi.org/10.3390/su141912481.
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Censusing wintering raptors has proved useful in detecting changes in populations. Israel is a well-known bottleneck for soaring birds in the autumn and the spring. Despite the many studies on migratory raptors in Israel, none have undertaken the study of the overwintering raptors consistently over extended periods, such as 1985–2022, a period of 38 years. During the study, conducted in central Israel, we recorded 44,120 individuals from 32 species. The most frequently observed species were Black Kite (Milvus migrans; 59.1%), Common Kestrel (Falco tinnunculus; 18.1%), and Steppe Buzzard (Buteo vulpinus; 6.6%). We found an increase in the total number of individuals, where the mean increase compared to the starting year was 851.6 ± 1071.2%, and the average annual growth was 43.7 ± 158.8%, respectively. A similar pattern was found in the number of species during the study period, where the mean annual increase was 17.1 ± 20.5%, and the average annual growth rate of species richness was 2.2 ± 16.2%. However, an evaluation of the mortality from power lines of two listed species suggests that the wintering raptors are not well protected in the study area. The conservation of these raptors and the possible sustainability of their wintering populations into the future, some of which are on the IUCN Red List, are of great importance, and the authorities should try and understand the human demographics and mesohabitat changes that appear to influence the wintering capabilities of the raptor populations.
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Eduardo, Carlos, Alencar Carvalho, and Miguel Ângelo Marini. "Distribution patterns of diurnal raptors in open and forested habitats in south-eastern Brazil and the effects of urbanization." Bird Conservation International 17, no. 4 (December 2007): 367–80. http://dx.doi.org/10.1017/s0959270907000822.
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AbstractDiurnal raptors may be highly sensitive to anthropogenic disturbances. We evaluated the diversity and abundance of diurnal raptors at an Atlantic Forest–cerrado transition zone in relation to two habitat types (forest fragments and open habitats) and to urbanization, comparing natural open and forested habitats with corresponding habitats within a large urban area. We sampled 80 points, 20 in each of four habitats (semi-natural and urban forests, semi-natural and urban open areas), during 12 months. Diurnal raptors recorded (21 species) included only three out of 10 species with some level of threat in the region. Forested habitats had more species (17) than open habitats (12). Urban areas had only 14 (67%) species, whereas semi-natural areas had all 21 species. Diurnal raptors were as abundant in urban areas as in semi-natural areas in spite of a loss in species richness in urban areas. A re-analysis without Caracara plancus showed that urban areas had a lower mean number of individuals per point than semi-natural areas. Overall species richness usually fluctuated from 14 to 16 species, being slightly higher between January and May than in other months. Overall abundance of diurnal raptors was much higher during summer than during winter. Local extinction may have already occurred for some species of diurnal raptors in the region and will probably shortly include several others. At least C. plancus, a habitat generalist, requires further studies and eventually management actions, since it is able to reach high population numbers in urbanized areas. Furthermore, highly sensitive species that were not recorded require further investigation regarding their conservation status.ResumoRaptores diurnos podem ser altamente sensíveis a perturbações antropogênicas. Avaliamos a diversidade e a abundância de raptores diurnos em uma região de transição entre Floresta Atlântica e Cerrado em relação a dois tipos de hábitats (fragmentos florestais e hábitats abertos) e è urbanização, comparando hábitats abertos e florestais aos hábitats correspondentes dentro de uma área urbana. Amostramos 80 pontos, 20 em cada um dos quatro hábitats (florestas semi-naturais e urbanas, áreas abertas semi-naturais e urbanas) durante 12 meses. Entre os raptores diurnos registrados (21 espécies) estão apenas três das 10 espécies com algum nível de ameaça na região. Mais espécies foram registradas nos hábitats florestados (17) do que nos hábitats abertos (12). Apenas 14 (67 %) espécies foram registradas nas áreas urbanas, enquanto as 21 espécies foram registradas nas áreas semi-naturais. Os raptores diurnos foram igualmente abundantes nas áreas urbanas e nas áreas semi-naturais independentemente da perda de espécies nas áreas urbanas. Uma nova análise sem Caracara plancus mostrou que as áreas urbanas tiveram um menor número médio de indivíduos por ponto do que as áreas semi-naturais. A riqueza total de espécies foi de 14 e 16 espécies, em geral, sendo um pouco mais alta entre janeiro e maio do que nos outros meses. A abundância total de raptores diurnos foi muito maior durante o verão do que no inverno. Algumas espécies de raptores diurnos já podem estar localmente extintas na região, o que ainda pode ocorrer para várias outras espécies em breve. Pelo menos C. plancus, uma espécie generalista de hábitat, necessita de mais estudos e eventualmente ações de manejo uma vez que pode atingir grandes tamanhos populacionais em áreas urbanizadas. Além disso, espécies altamente sensíveis que não foram registradas necessitam de mais investigações sobre seus status de conservação.
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Seibert, Brittany A., Michael K. Keel, Terra R. Kelly, Roger A. Nilsen, Paula Ciembor, Denise Pesti, Christopher R. Gregory, Branson W. Ritchie, and Michelle G. Hawkins. "Chlamydia buteonis in birds of prey presented to California wildlife rehabilitation facilities." PLOS ONE 16, no. 10 (October 13, 2021): e0258500. http://dx.doi.org/10.1371/journal.pone.0258500.
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Chlamydial infections, caused by a group of obligate, intracellular, gram-negative bacteria, have health implications for animals and humans. Due to their highly infectious nature and zoonotic potential, staff at wildlife rehabilitation centers should be educated on the clinical manifestations, prevalence, and risk factors associated with Chlamydia spp. infections in raptors. The objectives of this study were to document the prevalence of chlamydial DNA shedding and anti-chlamydial antibodies in raptors admitted to five wildlife rehabilitation centers in California over a one-year period. Chlamydial prevalence was estimated in raptors for each center and potential risk factors associated with infection were evaluated, including location, species, season, and age class. Plasma samples and conjunctiva/choana/cloaca swabs were collected for serology and qPCR from a subset of 263 birds of prey, representing 18 species. Serologic assays identified both anti-C. buteonis IgM and anti-chlamydial IgY antibodies. Chlamydial DNA and anti-chlamydial antibodies were detected in 4.18% (11/263) and 3.14% (6/191) of patients, respectively. Chamydial DNA was identified in raptors from the families Accipitridae and Strigidae while anti-C.buteonis IgM was identified in birds identified in Accipitridae, Falconidae, Strigidae, and Cathartidae. Two of the chlamydial DNA positive birds (one Swainson’s hawk (Buteo swainsoni) and one red-tailed hawk (Buteo jamaicensis)) were necropsied, and tissues were collected for culture. Sequencing of the cultured elementary bodies revealed a chlamydial DNA sequence with 99.97% average nucleotide identity to the recently described Chlamydia buteonis. Spatial clusters of seropositive raptors and raptors positive for chlamydial DNA were detected in northern California. Infections were most prevalent during the winter season. Furthermore, while the proportion of raptors testing positive for chlamydial DNA was similar across age classes, seroprevalence was highest in adults. This study questions the current knowledge on C. buteonis host range and highlights the importance of further studies to evaluate the diversity and epidemiology of Chlamydia spp. infecting raptor populations.
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Kindangen, Nicky. "KEPADATAN DAN FREKUENSI JENIS BURUNG PEMANGSA DI HUTAN GUNUNG EMPUNG, TOMOHON, SULAWESI UTARA." JURNAL ILMIAH SAINS 11, no. 1 (April 1, 2011): 36. http://dx.doi.org/10.35799/jis.11.1.2011.38.
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Tujuan penelitian ini adalah untuk menentukan kepadatan dan frekuensi jenis-jenis burung pemangsa yang hidup di hutan Gunung Empung, Tomohon, Sulawesi Utara. Penelitian ini dilaksanakan selama kurang lebih 2 bulan, yaitu dari awal bulan Oktober hingga akhir November 2010. Penelitian ini menggunakan metode Titik Hitung yang ditempatkan secara acak mulai dari ketinggian 1000 m di atas permukaan laut (dpl) hingga ke puncak gunung. Hasil penelitian menunjukkan bahwa di hutan Gunung Empung terdapat 3 jenis burung pemangsa, yaitu Accipiter griseiceps, Accipiter gularis dan Milvus migrans. Burung pemangsa dengan kepadatan tertinggi adalah Milvus migrans, sedangkan burung pemangsa dengan frekuensi kehadiran tertinggi adalah Accipiter gularis. DENSITY AND FREQUENCY OF RAPTORS SPECIESAT MOUNT EMPUNG’S FOREST, TOMOHON, NORTH SULAWESIABSTRACTThe aim of this research was to determine the density and frequency of raptors at Mount Empung, Tomohon, North Sulawesi. This research was carried out for approximately 2 months, from early October until the end of November 2010. The method used for this research was Spot Count Method that was randomly placed from the altitude 1000 m above the sea surface to the top of the mount. The result showed that 3 species of raptors inhabited Empung’s forest, i.e. Accipiter griseiceps, Accipiter gularis and Milvus migrans. Raptor with the highest density rate was Milvus migrans, whereas the most frequent raptor was Accipiter gularis.
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Mazal, Vlatka Dumbović, and Krešimir Mikulić. "A preliminary overview of monitoring for raptors in Croatia." Acrocephalus 33, no. 154-155 (December 1, 2012): 191–201. http://dx.doi.org/10.2478/v10100-012-0006-8.
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Abstract There are 40 regularly occurring raptor species in Croatia (diurnal raptors and owls), but only for two species (Griffon Vulture Gyps fulvus and Eleonora’s Falcon F. eleonorae) long-term monitoring (more than 10 years) of significant parts (i.e. > 80%) of their national population has been implemented. For 23 species (58%), the coverage of monitoring is limited to several locations (often within borders of given protected area), involving small percentage of national population or/and has started recently. Therefore, they do not satisfy the main purpose of national monitoring programmes, i.e. to draw conclusions about the trend of the species’ national population and to support the decision-making process about conservation measures to be applied. Besides the Institute of Ornithology and several ornithological NGOs, which are recognized as main actors for the implementation of raptors monitoring, the State Institute for Nature Protection (SINP) is setting up a framework for the nationwide bird monitoring complying with the legal provisions of the EU Birds Directive and the Natura 2000 network. The highest priority is to improve the coordination between state institutions, scientific and non-governmental organizations involved in raptor conservation with the final aim to develop a national raptor conservation strategy that sets priority target species and standardized monitoring systems
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Craighead, Derek, and Roger Smith. "Breeding Raptor Census in Grand Teton National Park, 2001." UW National Parks Service Research Station Annual Reports 25 (January 1, 2001): 51–62. http://dx.doi.org/10.13001/uwnpsrc.2001.3453.
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We documented abundance and diversity of raptors in a relatively undisturbed landscape in Grand Teton National Park, Wyoming, from February through August 2001. We located a total of 38 nesting pairs / 31.1 km, and a total of 8 raptor species. The American kestrel (Falco sparverius) and the Common raven (Corvus corax) were the two most abundant species on the study area. In this study, we considered Common ravens as an ecological and trophic level equivalent of raptors. Five of the eight species migrate, and two of the eight species are known neotropical migrants. The mean number of young fledged for all species was 1.9 (range=0.2 to 3.1, SD=1.3). We located the territory but not a nest for three Great horned owl (Bubo virginianus) pairs. Low precipitation and warm temperatures characterized weather during the last two years. Effects of weather conditions and human disturbance on raptor abundance within the study area were examined.
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Craig, Tim, and Erica H. Craig. "Changes in Diurnal Cliff-Nesting Raptor Occurrence on the Ungalik River in Western Alaska: 1977, 1979, and 2008." ARCTIC 69, no. 3 (September 2, 2016): 225. http://dx.doi.org/10.14430/arctic4574.
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Diurnal cliff-nesting raptors were inventoried on the Ungalik River, Alaska, in 1977 and 1979. In 2008 we resurveyed the drainage, replicating the techniques used in 1979. The density of nesting raptors during the late nesting season has doubled in the past three decades, from six occupied territories detected in 1977 and four in 1979 to 12 in 2008. A single Peregrine Falcon (Falco peregrinus) was sighted during aerial surveys in 1977, and a pair of Peregrine Falcons was detected during a boat survey in 1979; however, nesting by these birds was not confirmed. In contrast, we detected five occupied Peregrine Falcon territories along the Ungalik River in 2008. Other changes in cliff-nesting raptor occurrence included a decrease in occupied Gyrfalcon (Falco rusticolus) territories from four in 1977 to one in 1979 and two in 2008, a decrease in Rough-legged Hawk (Buteo lagopus) nests from one in 1979 (none in 1977) to none in 2008, and increases in Golden Eagle (Aquila chrysaetos) nests, from two in 1977 and 1979 to five in 2008. Changes in the number of nests of cliff-nesting raptors in this small population may have resulted, in part, from natural variation associated with changes in weather or prey abundance. However, it is likely that the increase in nesting Peregrine Falcons is related to global population recovery. Our data indicate that factors other than available nesting sites limit cliff-nesting raptor numbers along the Ungalik River. Spatial analysis indicated that cliff-nesting raptor nests were most often on hills or cliffs that face away from the coast, which is the source of most storms.
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Bosakowski, Thomas, and Dwight G. Smith. "Comparative diets of sympatric nesting raptors in the eastern deciduous forest biome." Canadian Journal of Zoology 70, no. 5 (May 1, 1992): 984–92. http://dx.doi.org/10.1139/z92-140.
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Diets and food-niche metrics of nesting raptors were studied in the eastern deciduous forest biome of northern New Jersey, southeastern New York, and northwestern Connecticut. Raptor diets were determined from 2506 prey individuals recovered from prey remains and pellets collected from nest sites of a community consisting of five hawk and four owl species. Food-niche overlaps were higher on average in the hawk guild (0.422) than in the owl guild (0.342), correlating with increased species packing and decreased body size differences in the hawk guild. Differences in activity times (diurnal versus nocturnal) did not result in reduced food-niche overlap between diurnal and nocturnal raptors. The lack of interference-type competition probably allowed greater exploitative-type competition but was offset by nearly exclusive use of certain prey types by several raptor species. Thus, temporal niche differences ultimately did aid in the resource partitioning of food between hawks and owls. Overall, the forest raptor community displayed significant food-niche overdispersion, with 35 of 36 food-niche overlap values below the 0.6 "competition" threshold. This result would be expected in a community structured by competition.
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ALMEIDA-ROCHA, JULIANA MONTEIRO DE, JULIO AMARO BETTO MONSALVO, and LEONARDO DE CARVALHO OLIVEIRA. "Diet specialisation reduces the occupancy of cocoa agroforests by diurnal raptors." Bird Conservation International 29, no. 4 (March 5, 2019): 558–74. http://dx.doi.org/10.1017/s0959270919000017.
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SummaryHabitat loss and fragmentation, especially due to agriculture expansion, pose the main threats to biodiversity conservation. While some species are able to survive and proliferate in human-modified habitats (winner species), others are highly dependent on well-preserved habitats, being more vulnerable to extinction (losers). Many raptors can be considered loser species due to their high trophic position, large home ranges, and low reproductive rates. Consequently, this group is frequently used to reflect the environmental quality of habitats and the biodiversity status of communities. Here we describe the diurnal raptor assemblages found in shaded-cocoa agroforests (cabrucas) of Southern Bahia, Brazil, and the determinants of raptor occupancy in this system. We systematically surveyed diurnal raptors in 16cabrucasites using complementary sampling methods – active search, playback, and point-count – and modeled species occupancy using covariates related to vegetation structure, landscape, management intensity, and biological traits (body mass, trophic level, and diet specialisation). We found a high number of species (at least 18) as able to usecabrucasand a negative relationship between species occupancy and the degree of diet specialisation. Thus, our results suggest thatcabrucashave a high potential to mitigate the effects of forest loss and fragmentation on diurnal raptors, but this system alone may not support complete assemblages of this group. It highlights the need for the maintenance of forest remnants in the landscapes to increase species diversity at a regional scale and to assure the conservation of this group in Southern Bahian Atlantic Forest.
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Wilson, David, Simon Hulka, and Leon Bennun. "A review of raptor carcass persistence trials and the practical implications for fatality estimation at wind farms." PeerJ 10 (November 15, 2022): e14163. http://dx.doi.org/10.7717/peerj.14163.
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Bird and bat turbine collision fatalities are a principal biodiversity impact at wind energy facilities. Raptors are a group at particular risk and often the focus of post-construction fatality monitoring programs. To estimate fatalities from detected carcasses requires correction for biases, including for carcasses that are removed or decompose before the following search. This is addressed through persistence trials, where carcasses are monitored until no longer detectable or the trial ends. Sourcing sufficient raptor carcasses for trials is challenging and surrogates that are typically used often have shorter persistence times than raptors. We collated information from raptor carcass persistence trials to evaluate consistencies between trials and assess the implications of using persistence values from other studies in wind facility fatality estimates. We compiled individual raptor carcass persistence times from published sources along with information on methods and location, estimated carcass persistence using GenEst and ran full fatality estimates using the carcass persistence estimates and mock datasets for other information. We compiled results from 22 trials from 17 sites across four terrestrial biomes, with trials lasting between 7 and 365 days and involving between 11 and 115 carcasses. Median carcass persistence was estimated at 420 days (90% confidence interval (CI) of 290 to 607 days) for the full dataset. Persistence time varied significantly between trials (trial-specific persistence estimates of 14 (5–42) days to 1,586 (816–3,084) days) but not between terrestrial biomes. We also found no significant relationship between either the number of carcasses in the trial or trial duration and estimated carcass persistence. Using a mock dataset with 12 observed fatalities, we estimated annual fatalities of 25 (16–33) or 26 (17–36) individuals using a 14- or 28-day search interval respectively using global dataset. When using trial-specific carcass persistence estimates and the same mock dataset, estimated annual fatalities ranged from 22 (14–30) to 37 (21–63) individuals for a 14-day search interval, and from 22 (15–31) to 47 (26–84) individuals for a 28-day search interval. The different raptor carcass persistence rates between trials translated to small effects on fatality estimates when using recommended search frequencies, since persistence rates were generally much longer than the search interval. When threatened raptor species, or raptors of particular concern to stakeholders are present, and no site-specific carcass persistence estimates are available, projects should use the lowest median carcass persistence estimate from this study to provide precautionary estimates of fatalities. At sites without threatened species, or where the risk of collision to raptors is low, the global median carcass persistence estimate from this review could be used to provide a plausible estimate for annual raptor fatalities.
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Slobodník, Vladimír, Roman Slobodník, and Miroslav Dravecký. "Summary on raptors and owls ringing in Slovakia in 2007 and 2008." Slovak Raptor Journal 3, no. 1 (January 1, 2009): 63–72. http://dx.doi.org/10.2478/v10262-012-0035-1.
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Summary on raptors and owls ringing in Slovakia in 2007 and 2008This article provides brief information about the number, species and reports about ringed raptors and owls in Slovakia during the period 2007-2008. It is a continuation of similar results of the ringing of raptors and owls in the periods 2002-2004, 2005-2006. In 2007, from 1346 individuals of raptorial birds, 941 raptors and 405 owls of 24 species (16 species of raptors and 8 species of owls) including 805 raptors' and 218 owls' nestlings were ringed. In 2008, a total of 856 individuals were ringed, including 542 raptors and 314 owls of 25 species (15 species of raptors and 10 species of owls) including 421 raptors' and 113 owls' nestlings. Also in 2008, the number of ringed raptors and owls decreased by 36.4% in comparison to 2007.
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Hallingstad, Eric, Daniel Riser-Espinoza, Samantha Brown, Paul Rabie, Jeanette Haddock, and Karl Kosciuch. "Game bird carcasses are less persistent than raptor carcasses, but can predict raptor persistence dynamics." PLOS ONE 18, no. 1 (January 3, 2023): e0279997. http://dx.doi.org/10.1371/journal.pone.0279997.
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Researchers conduct post-construction fatality monitoring (PCFM) to determine a wind energy facility’s direct impacts on wildlife. Results of PCFM can be used to evaluate compliance with permitted take, potentially triggering adaptive management measures or offsetting mitigation; reducing uncertainty in fatality rates benefits wind companies, wildlife agencies, and other stakeholders. As part of PCFM, investigators conduct carcass persistence trials to account for imperfect detection during carcass surveys. In most PCFM studies, pen-raised game birds and other non-raptor surrogates have been used to estimate persistence of all large birds, including raptors. However, there is a growing body of evidence showing carcass persistence varies by bird type; raptor fatality estimates based on game bird carcass persistence may therefore be biased high. We conducted raptor and game bird carcass persistence field trials for 1 year at 6 wind energy facilities. Raptor carcass persistence varied by habitat and season, whereas the best-supported game bird model only included habitat. Raptor persistence probabilities were higher than corresponding game bird persistence probabilities for 13 of the 16 habitat and season combinations. Analysis of a curated large bird persistence meta-dataset showed that raptor carcass persistence varied by season, habitat, and region. The probability of persisting through a 30-day search interval ranged from 0.44 to 0.99 for raptors and from 0.16 to 0.79 for game birds. Raptor persistence was significantly higher than game bird persistence for 95% of the sampled strata. We used these carcass persistence estimates to develop linear mixed-effects models that predict raptor persistence probabilities based on estimated game bird persistence probabilities. Our scaling model provides an important statistical method to address gaps in raptor persistence data at sites in a broad range of landscape contexts in the continental United States and should be used to inform fatality estimation when site-specific raptor persistence data are limited or absent.
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Ruszkowski, Jakub J., Anetta Hanć, Marcin Komosa, Małgorzata Dzierzęcka, Tadeusz Mizera, Maciej Gogulski, and Anita Zaworska-Zakrzewska. "Profile of Selected Mineral Elements in Tibiotarsal Bone of the White-Tailed Sea Eagle in Its Natural Habitat." Animals 12, no. 20 (October 13, 2022): 2744. http://dx.doi.org/10.3390/ani12202744.
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Mineral bone composition (dry matter, bones ash, P, Ca, Zn, Mn, Mg, and Cu) and Pb levels of tibiotarsi of seven White-Tailed Sea Eagles were assessed. Lead intoxication in different bird species including waterfowl and raptors is being studied worldwide. The bones were analyzed for Pb by mass spectrometry with excitation in inductively coupled plasma (ICP-MS Elan DRC II) and for bone composition by Atomic Emission Spectrometer (Agilent 4100 Microwave Plasma). Pb levels ranging from 3.54 µg/g to 74.6 µg/g DM suggest that some of the investigated birds might have been intoxicated by Pb. Results of this analysis were divided into two groups of bones, with bone Pb levels higher and lower than Pb toxicity levels, and mineral bone compositions of both groups were compared. The present study shows the differentiation of bone mineral composition among seven examined White-Tailed Sea Eagles, considered a specific species in raptors. Pb intoxication may not have a major influence on mineral bone composition in raptors. It also suggests that assessing bone composition of raptor bones may help finding the possible cause of their deaths.
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DIXON, ANDREW, ROLLER MAMING, AMARKHUU GUNGA, GANKHUYAG PUREV-OCHIR, and NYAMBAYAR BATBAYAR. "The problem of raptor electrocution in Asia: case studies from Mongolia and China." Bird Conservation International 23, no. 4 (October 29, 2013): 520–29. http://dx.doi.org/10.1017/s0959270913000300.
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SummaryWe report a large number of raptors electrocuted on recently erected electricity distribution lines in the open landscapes of the Mongolian steppe and Qinghai-Tibetan plateau, China. Upland Buzzards Buteo hemilasius and Saker Falcons Falco cherrug, characteristic raptors of these bioregions, were among those found to be electrocuted. Raptor electrocution was a consequence of poorly designed hardware configurations on anchor poles along surveyed lines on the Qinghai-Tibetan Plateau and, additionally, on line poles in the Mongolian steppe. The design flaws were upright pin-insulators on earthed crossarms and the use of jump wires that passed over crossarms via pin insulators on anchor poles. Targeted mitigation of anchor poles could significantly reduce the incidence of electrocution on the lines surveyed on the Qinghai-Tibetan Plateau, whilst all poles on the lines surveyed in the Mongolian steppe require remediation to make them safe for raptors. The Mongolian steppe and the Qinghai-Tibetan Plateau are bioregions that hold the largest breeding and wintering populations of the globally threatened Saker Falcon. The existing and growing network of dangerous electricity distribution lines in these regions may potentially impact the Saker Falcon population, thus we suggest that preventative and/or mitigation measures are implemented.
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McClure, Christopher J. W., Denis Lepage, Leah Dunn, David L. Anderson, Sarah E. Schulwitz, Leticia Camacho, Bryce W. Robinson, et al. "Towards reconciliation of the four world bird lists: hotspots of disagreement in taxonomy of raptors." Proceedings of the Royal Society B: Biological Sciences 287, no. 1929 (June 17, 2020): 20200683. http://dx.doi.org/10.1098/rspb.2020.0683.
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There are currently four world bird lists referenced by different stakeholders including governments, academic journals, museums and citizen scientists. Consolidation of these lists is a conservation and research priority. In reconciling lists, care must be taken to ensure agreement in taxonomic concepts—the actual groups of individual organisms circumscribed by a given scientific epithet. Here, we compare species-level taxonomic concepts for raptors across the four lists, highlighting areas of disagreement. Of the 665 species-level raptor taxa observed at least once among the four lists, only 453 (68%) were consistent across all four lists. The Howard and Moore Checklist of the Birds of the World contains the fewest raptor species (528), whereas the International Ornithological Community World Bird List contains the most (580) and these two lists are in the most disagreement. Of the disagreements, 67% involved owls, and Indonesia was the country containing the most disagreed upon species (169). Finally, we calculated the amount of species-level agreement across lists for each avian order and found raptor orders spread throughout the rankings of agreement. Our results emphasize the need to reconcile the four world bird lists for all avian orders, highlight broad disagreements across lists and identify hotspots of disagreement for raptors, in particular.
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Fuller, Mark. "Migrating Raptors." Ecology 89, no. 4 (April 2008): 1176–77. http://dx.doi.org/10.1890/0012-9658(2008)89[1176:mr]2.0.co;2.
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Tucker, V. A. "Gliding flight: drag and torque of a hawk and a falcon with straight and turned heads, and a lower value for the parasite drag coefficient." Journal of Experimental Biology 203, no. 24 (December 15, 2000): 3733–44. http://dx.doi.org/10.1242/jeb.203.24.3733.
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Raptors - falcons, hawks and eagles in this study - such as peregrine falcons (Falco peregrinus) that attack distant prey from high-speed dives face a paradox. Anatomical and behavioral measurements show that raptors of many species must turn their heads approximately 40 degrees to one side to see the prey straight ahead with maximum visual acuity, yet turning the head would presumably slow their diving speed by increasing aerodynamic drag. This paper investigates the aerodynamic drag part of this paradox by measuring the drag and torque on wingless model bodies of a peregrine falcon and a red-tailed hawk (Buteo jamaicensis) with straight and turned heads in a wind tunnel at a speed of 11.7 m s(−)(1). With a turned head, drag increased more than 50 %, and torque developed that tended to yaw the model towards the direction in which the head pointed. Mathematical models for the drag required to prevent yawing showed that the total drag could plausibly more than double with head-turning. Thus, the presumption about increased drag in the paradox is correct. The relationships between drag, head angle and torque developed here are prerequisites to the explanation of how a raptor could avoid the paradox by holding its head straight and flying along a spiral path that keeps its line of sight for maximum acuity pointed sideways at the prey. Although the spiral path to the prey is longer than the straight path, the raptor's higher speed can theoretically compensate for the difference in distances; and wild peregrines do indeed approach prey by flying along curved paths that resemble spirals. In addition to providing data that explain the paradox, this paper reports the lowest drag coefficients yet measured for raptor bodies (0.11 for the peregrine and 0.12 for the red-tailed hawk) when the body models with straight heads were set to pitch and yaw angles for minimum drag. These values are markedly lower than value of the parasite drag coefficient (C(D,par)) of 0.18 previously used for calculating the gliding performance of a peregrine. The accuracy with which drag coefficients measured on wingless bird bodies in a wind tunnel represent the C(D,par) of a living bird is unknown. Another method for determining C(D,par) selects values that improve the fit between speeds predicted by mathematical models and those observed in living birds. This method yields lower values for C(D,par) (0.05-0.07) than wind tunnel measurements, and the present study suggests a value of 0.1 for raptors as a compromise.
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Kay, BJ, LE Twigg, TJ Korn, and HI Nicol. "The use of artifical perches to increase predation on house mice (mus domesticus) by raptors." Wildlife Research 21, no. 1 (1994): 95. http://dx.doi.org/10.1071/wr9940095.
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Changes in raptor and mouse abundance over time in response to the introduction of artificial perches for raptors were analysed using generalised linear models. The placement of artificial perches around the perimeter of irrigated soybean crops significantly increased the number of diurnal raptors visiting and hunting over these crops compared with untreated crops. This increased hunting pressure reduced (a) the rate at which the mouse population increased in the crops and (b) the maximum mouse population density. These effects were greater when artificial perches were placed at 100-m spacings rather than 200-m spacings. No significant reductions in mouse damage were detected as mice failed to reach threshold densities for crop damage on the untreated plots. Despite this, the use of artificial perches to attract birds of prey may be a useful addition to rodent management strategies.
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Tucker, V. A. "The deep fovea, sideways vision and spiral flight paths in raptors." Journal of Experimental Biology 203, no. 24 (December 15, 2000): 3745–54. http://dx.doi.org/10.1242/jeb.203.24.3745.
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Raptors - falcons, hawks and eagles in this study - have two regions of the retina in each eye that are specialized for acute vision: the deep fovea and the shallow fovea. The line of sight of the deep fovea points forwards and approximately 45 degrees to the right or left of the head axis, while that of the shallow fovea also points forwards but approximately 15 degrees to the right or left of the head axis. The anatomy of the foveae suggests that the deep fovea has the higher acuity. Several species of raptors in this study repeatedly moved their heads among three positions while looking at an object: straight, with the head axis pointing towards the object; or sideways to the right or left, with the head axis pointing approximately 40 degrees to the side of the object. Since raptors do not rotate their eyes noticeably in the sockets, these movements presumably cause the image of the object to fall on the shallow and deep foveae. The movements occurred approximately every 2 s on average in hawks and falcons, and approximately every 5 s in bald eagles. The proportion of time that the raptors spent looking straight or sideways at an object depended on how far away the object was. At a distances closer than 8 m, they spent more time looking at the object straight, but as the distance increased to 21 m, they spent more time looking at it sideways. At distances of 40 m or more, raptors looked sideways at the object 80 % or more of the time. This dependence of head position on distance suggests that raptors use their more acute sideways vision to look at distant objects and sacrifice acuity for stereoscopic binocular vision to look at close objects. Having their most acute vision towards the side causes a conflict in raptors such as falcons, which dive at prey from great distances at high speeds: at a speed of 70 m s(−)(1), turning their head sideways to view the prey straight ahead with high visual acuity may increase aerodynamic drag by a factor of 2 or more and slow the raptor down. Raptors could resolve this conflict by diving along a logarithmic spiral path with their head straight and one eye looking sideways at the prey, rather than following the straight path to the prey with their head turned sideways. Although the spiral path is longer than the straight path, a mathematical model for an ‘ideal falcon’ shows that the falcon could reach the prey more quickly along the spiral path because the speed advantage of a straight head more than compensates for the longer path.
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Steen, Ronny, Line M. Løw, and Geir A. Sonerud. "Delivery of Common Lizards (Zootoca (Lacerta) vivipara) to nests of Eurasian Kestrels (Falco tinnunculus) determined by solar height and ambient temperature." Canadian Journal of Zoology 89, no. 3 (March 2011): 199–205. http://dx.doi.org/10.1139/z10-109.
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Recent development in video monitoring has allowed collecting of data on prey deliveries at raptor nests, and this offers an opportunity to relate prey selection to short-term changes in environmental factors on a scale of hours. Whereas raptors may specialize on ectothermic prey at southern latitudes, only some generalist raptors may include such prey in their diet at northern latitudes. In particular, at northern latitudes the activity pattern of ectothermic reptiles is strongly dependent on the prevailing weather conditions. To test whether this dependence affects the exposure of reptiles to raptors, we used video recording of prey deliveries at nests of the Eurasian Kestrel ( Falco tinnunculus L., 1758) at 61°N in Norway, where the Common Lizard ( Zootoca ( Lacerta ) vivipara (Jacquin, 1787)) is the only lizard available to kestrels. The probability that a prey item delivered at a kestrel nest was a lizard increased towards midday and also increased independently with increasing ambient temperature, which on average, was 20.2 °C when lizards were delivered compared with 15.7 °C when other types of prey were delivered. Thus, the delivery of lizards by kestrels in our study may be regarded as a functional response, where the abundance of lizards is determined by solar height and ambient temperature.
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Slobodník, Vladimír. "Summary on raptors and owls ringing in Slovakia in the period 2005-2006." Slovak Raptor Journal 2, no. 1 (January 1, 2008): 113–17. http://dx.doi.org/10.2478/v10262-012-0025-3.
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Summary on raptors and owls ringing in Slovakia in the period 2005-2006This report provides a summary on raptors and owls ringing in Slovakia in 2005-2006. In 2005, from a total of 21 132 ringed birds, raptors and owls represented 964 ind. (4.5 %). There were 26 species of raptors and owls, which equates 15.5 % of all species recorded. In 2006, there were 29 075 ringed in Slovakia, from this number raptors and owls were represented by 703 ind. (2.4 %) and 23 species (14 %). This paper also contains a summary on the ringing recoveries including data on raptors and owls.
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Hoffman, Rob. "The contribution of raptorial birds to patterning in small mammal assemblages." Paleobiology 14, no. 1 (1988): 81–90. http://dx.doi.org/10.1017/s0094837300011817.
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Seven taxa of raptorial birds were experimentally fed a controlled sample of 50 house mice (Mus musculus). Bones recovered from the pellets were examined for interspecies variability in preservation to assess the potential contribution of specific raptors to patterning in fossil assemblages. Quantitative analyses demonstrate that patterns in bone fragmentation may assist in the identification of particular raptor species as depositional agents in small mammal assemblages.
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Fülöp, Attila, Lőrinc Bărbos, Gábor M. Bóné, Szilárd J. Daróczi, Luca A. Dehelean, Réka B. Kiss, István Kovács, Attila Nagy, and Tamás Papp. "Autumn migration of soaring birds in North Dobrogea, Romania: a study with implications for wind farm development." Ornis Hungarica 20, no. 2 (December 1, 2012): 73–85. http://dx.doi.org/10.2478/orhu-2013-0009.
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Abstract In Dobrogea, a core area for wind energy exploitation in Romania, existing knowledge regarding the intensity and pattern of bird migration is limited. In the absence of enumerated data, wind farms may be constructed in areas where large aggregations of migrants pass. In this study we recorded the intensity of the autumn migration of soaring birds in three locations within the Măcin Mountains, where wind farms are planned to be built. The locations chosen were at Văcăreni, Greci and Cerna villages. Furthermore we categorized all migrating individuals as threatened or non-threatened by the planned wind farms, based on their migration routes and height at local scale. At Văcăreni 4.716 individuals were counted, 3.394 raptors and 1.322 non-raptors, at Greci 2.387 individuals, 2.064 raptors and 323 non-raptors, and finally at Cerna, 5.268 individuals, 4.529 raptors and 739 non-raptors. At all three sites a significant proportion of birds, both raptors and non-raptors, were found to be threatened by the proposed wind farms. At Văcăreni 68.33% of raptors and 84.95% of non-raptors were at threat, at Greci 44.48% and 54.18% respectively, and at Cerna 59.37% and 94.86%. As such we conclude that intensive migration occurs in North Dobrogea and wind farms would have a considerable negative impact on migrants in the studied areas