Western Osprey (Pandion haliaetus) Science Article 2 abstract This study examined the relationship between brood size and energetic expenditure of male Ospreys. The daily energetic expenditure (DEE) of male Ospreys, provisioning nestlings and providing post-fledging parental care, was estimated using detailed time-energy budgets. Factors affecting DEE were investigated, and DEE and the maximum rate of […]
Category: Worldwide oriental region
Courtship Feeding And Osprey Reproduction
Western Osprey (Pandion haliaetus) Science Article 1 abstract A female Osprey (Pandion haliaetus) usually is fed exclusively by its mate between pair formation and egg-laying. Laying dates and courtship periods, but not clutch size, egg size, breeding success or female weight reserves, were correlated (negatively) with the prelaying feeding rates of 12 females breeding in […]
The occurrence of fault bars in the plumage of nestling Ospreys.
Western Osprey (Pandion haliaetus) Science Article 3 abstract We document the occurrence of fault bars in a population of nestling Ospreys Pandion haliaetus under natural conditions. Ospreys had an average of 9.9 fault bars on their rectrices, however variation was large. Fault bar formation declined linearly with age and increased symmetrically from outer to inner […]
Variation in the quality of parental care at falcon nests in South Africa as evidence for postulated differences in food availabi lity.
Peregrine Falcon (Falco peregrinus) Science Article 1 abstract Parental care by Peregrine Falcons Falco peregrinus an d Lanner Falcons F. biarmicus during the nestling period was studied in two areas of South Africa. Comparisons were made between the quality of care administered to broods of Peregrine Falcons at nests in tropical (the Soutpansberg) an d […]
Identification of natal locales of peregrine falcons (falco peregrinus) by trace-element analysis of feathers
Peregrine Falcon (Falco peregrinus) Science Article 12 abstract Samples of secondary remiges collected from nestling Peregrine Falcons (Falco peregrinus) in Alaska and western Greenland were analyzed for trace-element content using instrumental neutron-activation analysis. Concentrations of 14 trace elements were subjected to a series of multivariate discriminant function analyses to ascertain whether or not these concentrations […]
Kleptoparasitism by Peregrine Falcons on Carrion Crows
Peregrine Falcon (Falco peregrinus) Science Article 4 abstract […]. The study area was Bizkaia, a small province of 2300 km2 located in the north of Spain. In this area we have monitored about 35-38 Peregrine territories since 1997. During this time we have studied the prey of Peregrines in the nests, recording 931 prey of […]
Genetic relationships in the peregrine falcon (Falcoperegrinus) analysed by microsatellite DNA markers
Peregrine Falcon (Falco peregrinus) Science Article 10 abstract Microsatellite DNA markers were developed from a peregrine falcon (Falco peregrinus)and genetic relationships among peregrine falcons in southern Norway were analysedusing the markers. The genomic DNA library was screened for the presence of dinucleotidemicrosatellite repeats. Twelve loci revealed polymorphism through the initial analysis of24 unrelated peregrine falcons, […]
Population size and factors affecting the density of the Peregrine Falcon in Spain
Peregrine Falcon (Falco peregrinus) Science Article 3 abstract By means of bibliographical searches and requests of unpublished information from ornithologists and public administrations all over the country, the population size estimate of the Peregrine Falcon Falco peregrinus in Spain is updated. Spanish population is estimated at 2435-2743 pairs, which represents a mean density of 5.1 […]
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
Peregrine Falcon (Falco peregrinus) Science Article 6 abstract 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 deg to one side to see the prey […]
Rock climbing and Raven Corvus corax ocurrence depress breeding success of cliff-nesting Peregrines Falco peregrinus
Peregrine Falcon (Falco peregrinus) Science Article 5 abstract Aims: To assess the significance of rock climbing-induced disturbance and Raven Corvus corax occurrence on the breeding output of a cliff-nesting Peregrine Falco peregrinus population.Location: Northern Italy- southern Switzerland.Methods: Breeding success, productivity and fledgling rate of 29 Peregrine pairs were analysed in relation to the occurrence of […]