Modelling growth rates and developing an age determination tool for nestling Bonelli's Eagle Aquila fasciata

Annals of Applied Biology, Journal Year: 2025, Volume and Issue: unknown

Published: March 13, 2025

Abstract Understanding the growth rate of nestlings is essential for explaining developmental strategies and particularly important birds prey. Given that they have lower reproduction rates than other species, could be one critical factors determining parental fitness influencing individual's condition. Despite variability often resulting from various stress conditions, predictable given ages nestlings, as highlighted here. This study investigates dynamics Bonelli's Eagle ( Aquila fasciata ) in Republic Cyprus, focusing on 13 biometric variables measured over time. We employed logistic generalized additive models to analyse trajectories identify predictors age. Our findings highlight achieve maximum body mass tarsus length early development, followed by primary feathers wing length. Conversely, head width, beak dimensions, talon exhibit slower more gradual growth. Precisely describing pattern individual components enabled us develop a tool predicting found wing, tarsus, middle lengths are most reliable nestling The effectiveness test our predictive model conducted an independent data set showed age estimation error 1 day. Thus, research provides deep insight into eagles’ patterns while offering practical tools field studies conservation efforts.

Language: Английский

Absence of negative effect of GPS‐tags on survival and breeding success in a long‐lived territorial raptor

Ibis, Journal Year: 2025, Volume and Issue: unknown

Published: March 19, 2025

GPS tracking has enabled significant advances in the study of animal movements such as migration and habitat use. However, devices can affect behaviour tagged individuals, especially for flying animals birds, may ultimately impair their reproduction and/or survival. While numerous studies have investigated potential negative effects GPS‐tags on few simultaneously looked at these survival, with latter sometimes suffering from methodological flaws. This GPS‐tagging breeding success survival a medium‐sized raptor, Bonelli's Eagle Aquila fasciata . Forty‐five adults were equipped backpack‐mounted representing 1.2–3.5% individual body mass. Using recently developed capture–mark–recapture model that accounts differences detectability between types tags (metal ring, coloured ring or GPS), our results showed no GPS‐tagged banded individuals. Overall, we did not observe deleterious would warn against use this species, other medium‐to‐large raptors, given relevant information they might provide conservation.

Language: Английский

Both movements and breeding performance are affected by individual experience in the Bonelli's eagle Aquila fasciata

Ecology and Evolution, Journal Year: 2024, Volume and Issue: 14(7)

Published: July 1, 2024

Movement is a key behaviour to better understand how individuals respond their environment. behaviours are affected by both extrinsic factors that face, such as weather conditions, and intrinsic factors, sex experience. Because of the energy costs it entails, movement can have direct consequences on an individual's demographic parameters-and ultimately population dynamics. However, relationship between daily parameters breeding performance poorly known, in particular for central place forager territorial species. We investigated here link French Bonelli's eagle (

Language: Английский