| flexibility in a changing arctic food web: can rough-legged buzzards cope with changing small rodent communities? | indirect effects of climate change are often mediated by trophic interactions and consequences for individual species depend on how they are tied into the local food web. here we show how the response of demographic rates of an arctic bird of prey to fluctuations in small rodent abundance changed when small rodent community composition and dynamics changed, possibly under the effect of climate warming. we observed the breeding biology of rough-legged buzzards (buteo lagopus) at the erkuta tundra ... | 2019 | 31390125 |
| dde residues and eggshell changes in alaskan falcons and hawks. | eggshell thickness after exposure to ddt was reduced by 21.7 percent in alaskan tundra peregrines, by 16.8 percent in taiga peregrines, by 7.5 percent in aleutian peregrines, by 3.3 percent in rough-legged hawks, and not at all in gyrfalcons. tundra peregrine eggs contain an average of 889 parts of dde per million (lipid basis); taiga peregrine eggs contain 673 parts per million; aleutian peregrine eggs contain 167 parts per million; rough-legged hawk eggs contain 22.5 parts per million; and gyr ... | 1971 | 5573569 |
| cranial nerve deficits in a rough-legged hawk. | | 1980 | 6245347 |
| visceral gout in a rough legged hawk (buteo lagopus). | visceral gout is reported for the first time in a rough legged hawk (buteo lagopus). urate crystals were present on the pericardium, thoracic and abdominal air sacs, and the ventral surface of the liver. the liver and spleen also had urate crystals throughout the parenchyma. there was no indication of articular or renal involvement. the immediate cause of death in this hawk was not identified, but appeared to result from multiple factors, including the visceral gout. | 1987 | 3625918 |
| fluctuations of observed breeding rough-legged hawks and gyrfalcons: regularity reconsidered. | we recently assessed regularity in fluctuation of annual numbers of breeding pairs observed for several raptor species, and found no indication of reputed regular or cyclic fluctuations in our colville river, alaska sample for gyrfalcons (falco rusticolus) or rough-legged hawks (buteo lagopus) (mindell et al. 1987). discussions with colleagues have prompted us to expand our analysis and clarify key points. we present time series analyses, using the colville river sample size and interval (13 sur ... | 1988 | 28312308 |
| functional responses of the rough-legged buzzard in a multi-prey system. | the functional response is a key element of predator-prey interactions. basic functional response theory explains foraging behavior of individual predators, but many empirical studies of free-ranging predators have estimated functional responses by using population-averaged data. we used a novel approach to investigate functional responses of an avian predator (the rough legged-buzzard buteo lagopus pontoppidan, 1763) to intra-annual spatial variation in rodent density in subarctic sweden, using ... | 2014 | 24448699 |
| the mitochondrial genomes of aquila fasciata and buteo lagopus (aves, accipitriformes): sequence, structure and phylogenetic analyses. | the family accipitridae is one of the largest groups of non-passerine birds, including 68 genera and 243 species globally distributed. in the present study, we determined the complete mitochondrial sequences of two species of accipitrid, namely aquila fasciata and buteo lagopus, and conducted a comparative mitogenome analysis across the family. the mitogenome length of a. fasciata and b. lagopus are 18,513 and 18,559 bp with an a + t content of 54.2% and 55.0%, respectively. for both the two acc ... | 2015 | 26295156 |
| correction: the mitochondrial genomes of aquila fasciata and buteo lagopus (aves, accipitriformes): sequence, structure and phylogenetic analyses. | | 2015 | 26469400 |
| breeding population fluctuations in some raptors. | we investigated differences in annual breeding population stability and its relationship to diversity in food habits for several species of raptors. chi-square tests showed no significant differences between observed and expected (based on logistic growth equation) breeding population sizes for peregrine falcons (falco peregrinus) during recovery from pesticide induced declines in 4 alaskan populations. this indicates that no major peregrine falcon population fluctuations occurred aside from the ... | 1987 | 28311134 |
| new host records for parasitic mites of the family syringophilidae from accipitriform birds (aves: accipitriformes). | four accipitriform bird species of the family accipitridae are reported as new hosts for quill mites (acari: cheyletoidea: syringophilidae): megasyringophilus aquilus skoracki, lontkowski and stawarczyk, 2010 was collected from hieraaetus pennatus gmelin, 1788 in france and spain, and buteo jamaicensis gmelin, 1788 in canada; peristerophila accipitridicus skoracki, lontkowski and stawarczyk, 2010 was collected from circaetus gallicus gmelin, 1788 in france, and buteo lagopus pontoppidan, 1763 in ... | 2015 | 26878628 |
| predation pressure by avian predators suggests summer limitation of small-mammal populations in the canadian arctic. | predation has been suggested to be especially important in simple food webs and less productive ecosystems such as the arctic tundra, but very few data are available to evaluate this hypothesis. we examined the hypothesis that avian predators could drive the population dynamics of two cyclic lemming species in the canadian arctic. a dense and diverse suite of predatory birds, including the snowy owl (bubo scandiacus), the rough-legged hawk (buteo lagopus), and the long-tailed jaeger (stercorariu ... | 2014 | 24649646 |
| high exposure rates of anticoagulant rodenticides in predatory bird species in intensively managed landscapes in denmark. | the extensive use of anticoagulant rodenticides (ars) for rodent control has led to widespread secondary exposure in nontarget predatory wildlife species. we investigated exposure rates and concentrations of five ars in liver samples from five raptors and six owls from denmark. a total of 430 birds were analysed. ars were detected in 84-100 % of individual birds within each species. multiple ar exposure was detected in 73 % of all birds. average number of substances detected in individual birds ... | 2012 | 22588365 |
| regional distribution shifts help explain local changes in wintering raptor abundance: implications for interpreting population trends. | studies of multiple taxa across broad-scales suggest that species distributions are shifting poleward in response to global climate change. recognizing the influence of distribution shifts on population indices will be an important part of interpreting trends within management units because current practice often assumes that changes in local populations reflect local habitat conditions. however, the individual- and population-level processes that drive distribution shifts may occur across a lar ... | 2014 | 24466253 |
| network topology of stable isotope interactions in a sub-arctic raptor guild. | predation is an ecologically important process, and intra-guild interactions may substantially influence the ecological effects of predator species. despite a rapid expansion in the use of mathematical graph theory to describe trophic relations, network approaches have rarely been used to study interactions within predator assemblages. assemblages of diurnal raptors are subject to substantial intra- and interspecific competition. here we used the novel approach of applying analyzes based on netw ... | 2016 | 27209296 |
| vulnerability of subarctic and arctic breeding birds. | recent research predicts that future climate change will result in substantial biodiversity loss associated with loss of habitat for species. however, the magnitude of the anticipated biodiversity impacts are less well known. studies of species vulnerability to climate change through species distribution models are often limited to assessing the extent of species' exposure to the consequences of climate change to their local environment, neglecting species sensitivity to global change. the likel ... | 2017 | 28052503 |
| fatal pox infection in a rough-legged hawk. | natural pox infection occurred in a free-living rough-legged hawk (buteo lagopus) in northeastern north dakota. gross, histological and electron microscopic findings were typical of pox infection, and characteristic lesions developed in red-tailed hawks (buteo jamaicensis) but not in great horned owls (bubo virginianus) following inoculation with case material. death of the rough-legged hawk was attributed to starvation rsulting from inability to capture prey and to blood loss from foot lesions. | 2003 | 167207 |
| serological and parasitological prevalence of toxoplasma gondii in wild birds from colorado. | ground-feeding birds are considered important in the epidemiology of toxoplasma gondii because they serve as indicators of soil contamination by oocysts, and birds of prey are indicators of t. gondii prevalence in rodents and other small mammals. cats excrete environmentally resistant oocysts after consuming tissues of t. gondii -infected birds. in the present study, sera and tissues from 382 wild birds from colorado were tested for t. gondii infection. antibodies to t. gondii were found in 38 b ... | 2010 | 20950101 |
| lesions associated with pasteurella multocida infection in raptors. | several case reports attest to the pathogenicity of pasteurella multocida in raptors; however, the pathologic syndromes have not been fully described. we describe here the lesions encountered in 22 avian cholera cases in raptors. besides septicemia-related lesions, a unique syndrome of esophageal abscesses was noted in 8 of the 11 (73%) buteo hawks that succumbed to avian cholera. esophageal abscesses were not noted in birds belonging to the order strigiformes (owls) or family falconidae (falcon ... | 1997 | 9087338 |
| isolation of a mycoplasma sp. from three buzzards (buteo spp.). | mycoplasma spp. were isolated from the respiratory tissues of three buzzards. bird i, a rough-legged buzzard (buteo lagopus), showed airsacculitis, catarrhal-fibrinous pneumonia, and catarrhal tracheitis. bird ii, a common buzzard (buteo buteo), revealed mycotic airsacculitis, bronchitis and pneumonia. bird iii was a healthy rough-legged buzzard. all isolates metabolized glucose but not arginine and were serologically identical by immunofluorescence and growth-inhibition tests. no serological cr ... | 1982 | 7049150 |
| tularemia in a rough-legged buzzard (buteo lagopus) and a ural owl (strix uralensis). | | 1983 | 6644938 |
| resource partitioning among avian predators of the arctic tundra. | interspecific competition can play a key role in structuring ecological communities. the arctic tundra is a low productivity ecosystem supporting simple food webs, but several predators often feed on the same prey species, lemmings, known for their large-amplitude population fluctuations. we examined mechanisms involved in reducing intra-guild competition and allowing coexistence of four avian predators (snowy owls, glaucous gulls, rough-legged hawks and long-tailed jaegers) feeding on a pulsed ... | 2020 | 32965060 |