Ranging Behavior of Non-Breeding and Breeding Adult White-Tailed Eagles

Abstract

Space utilization by animals is vital for species ecology but also a valuable predictor of habitat conditions and environment capacity for a given species. We investigated the ranging behavior of the white-tailed eagle, an apex predator experiencing a significant population increase and saturation. Comparing five adult floaters and two breeding males tracked with GPS loggers in Poland for 1–5 years, we observed substantial differences in space utilization. Breeding males occupied approximately 63 to 122 km2 (using 90% kernel density), while floaters ranged over roughly 6000 to 60,000 km2. Breeding males expanded their home ranges during successful breeding, with one male frequently flying 29 km to a foraging site when raising chicks but hardly doing so in other seasons. Both breeding males revisited nests more frequently in April and May (up to seven times daily, typically two to four), exhibiting distinct seasonal daily movement patterns. Floaters had slightly higher daily movement rates with a weak seasonal pattern. We conclude that breeding males’ ranging behavior depended on proximity to optimal foraging sites, while adult floaters engaged in prolonged wandering.

GPS Tracking Reveals the White-Tailed Eagle Haliaeetus albicilla as an Ambassador for the Natura 2000 Network

“…By using dBBMMs to analyze GPS telemetry data, we measured, in a relatively unbiased way, the selection of protected areas by white-tailed eagles in our study area [11,41]. We assume that the use of areas by white-tailed eagles is mainly determined by habitat quality and food availability, and in some cases, perhaps, intra-specific competition [15,42].…”

“…In Austria, about 70 breeding pairs of white-tailed eagles existed in 2023 (R. Probst et al, in prep.). While nesting pairs are known to be sedentary, juvenile, immature, and non-breeding, floating adults [11] move over large parts of central and eastern Europe in the course of their natal dispersion [12], which typically lasts several years in this delayedmaturity species [13]. Several studies have examined the process of natal dispersal in whitetailed eagles, and have recorded details such as timing [14], distances travelled [15,16], habitat use [17], degree of fidelity to the natal area upon recruitment [18], and the potential of human-wildlife conflicts associated with wind energy [19].…”

Are Current Protection Methods Ensuring the Safe Emancipation of Young Black Storks? Telemetry Study of Space Use by Black Storks (Ciconia nigra) in the Early Post-Breeding Period

“…The rapid development of telemetry, resulting in smaller transmitter sizes and lower costs, in recent years has allowed its wider use in the study of the biology of mainly large animal species, such as large raptors [ 1 , 2 , 3 , 4 , 5 ] and storks ( Ciconia sp.) [ 6 , 7 , 8 ].…”

“…Mobility during the initial period of independence of young BSs at the end of the breeding season until the day they definitively leave the nest and begin their migration has not yet been analyzed. This process is relatively well understood in raptors, in which several phases preceding dispersal have been identified [ 5 , 35 ]. One of these is a long period of flocking to parental territories under the care of adult birds, where the young are taught to forage for food.…”