- Open Access
Greedy nearest-neighbor approach to quantify site revisitation: Comparing two sympatric raven species
Phys. Rev. Research 8, 043149 – Published 10 November, 2026
DOI: https://doi.org/10.1103/z84g-799z
Abstract
A central challenge in movement ecology is to describe ecologically meaningful residence sites from raw tracking data due to heterogeneous sampling frequency and uncertain site boundaries. Here, we develop a greedy nearest-neighbor clustering approach with local reassignment and polygon-based site construction that generates timestamped sequences of site visits for each tracked individual, and apply it to 9 years of global positioning system (GPS) data from two sympatric raven species in the Dead Sea region—the fan-tailed raven (Corvus rhipidurus) and the brown-necked raven (C. ruficollis). Using the resulting visitation sequences, we quantify recursion patterns using the non-Markovian individual mobility model (IMM), which captures the balance between novel-site discovery and preferential return . The inferred dynamics are consistent with IMM predictions and reveal clear interspecific differences: brown-necked ravens continue to discover new sites at a higher rate (lower ), whereas fan-tailed ravens show a steeper concentration of visits among top-ranked sites. Entropy analyses further separate the species, with brown-necked ravens exhibiting higher site entropy and higher conditional entropy of site-to-site transitions. Together, these results provide a robust framework for describing interspecific differences in movement strategies that can be used to infer memory from GPS data and suggest distinct space-use strategies in two closely related sympatric species.
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