RT journal article
T1 Moving beyond curve fitting: using complementary data to assess alternative explanations for long movements of three vulture species
A1 Spiegel, Orr
A1 Harel, Roi
A1 Centeno Cuadros, Alejandro
A1 Hatzofe, Ohad
A1 Getz, Wayne M.
A1 Nathan, Ran
A2 BiomedicinaBiotecnología y Salud Pública
K1 movement ecology
K1 Lévy flight foraging hypothesis
K1 sex-biased dispersal
K1 fat-tailed step-size distribution
K1 wildlife biotelemetry
K1 3-D accelerometers
AB Animal movements exhibit an almost universal pattern of fat-tailed step-size distributions, mixing short and very long steps. The Lévy flight foraging hypothesis (LFFH) suggests a single optimal food search strategy to explain this pattern, yet mixed movement distributions are biologically more plausible and often convincingly fit movement data. To confront alternative explanations for these patterns, we tracked vultures of three species in two very different ecosystems using high-resolution global positioning system/accelerometer tags accompanied by behavioral, genetic, and morphological data. The Lévy distribution fitted the data sets reasonably well, matching expectations based on their sparsely distributed food resources; yet the fit of mixed models was considerably better, suggesting distinct movement modes operating at three different scales. Specifically, long-range forays (LRFs)—rare, short-term, large-scale circular journeys that greatly exceed the typical foraging range and contribute to the tail-fatness of the movement distribution in all three species—do not match an optimal foraging strategy suggested by the LFFH. We also found no support for preferred weather conditions or population genetic structure as alternative explanations, so the hypothesis that LRFs represent failed breeding dispersal attempts to find mates remains our most plausible explanation at this time. We conclude that inference about the mechanisms underlying animal movements should be confronted with complementary data, and suggest that mixed behavioral modes likely explain commonly observed fat-tailed movement distributions.
PB The University of Chicago Press
SN 0003-0147
YR 2015
FD 2015-02
LK http://hdl.handle.net/10498/29929
UL http://hdl.handle.net/10498/29929
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 12-nov-2026