Exploring Dietary Patterns of Migratory Avifauna in the the Galite Archipelago (Tunisia) through Stable Isotope Analysis

Abstract

This research examines the dietary preferences of prey species targeted by Falco eleonorae, with a focus on analyzing isotopic signatures including δ¹³C, δ¹⁵N and δ³⁴S values. Our study uncovers significant variations in isotopic signatures among prey species, reflecting their distinct trophic levels and geographical origins. The δ¹³C values of European storm petrel notably is associated with marine sources. Conversely, the spotted flycatcher exhibits unexpectidely high δ¹³C and δ¹⁵N values, warranting further investigation into its dietary habits. Interestingly, the European greenfinch demonstrates fluctuations in intrafeather amplitude during molting season suggesting dietary shift despite its primarily granivorous nature. While some prey species align with existing literature, caution is advised in generalizing these findings due to sample size limitations. The acquisition of a substantial sample size is imperative for discerning subtle variations and thoroughly examining stable isotope signatures, thereby enhancing our understanding of prey dietary patterns. Consequently, this study underscores the necessity of further robust analysis to attain a nuanced comprehension of ecological dynamics within avian community.