Giovedì, 12 Luglio 2018 dalle ore 14:00 alle ore 15:00
Sala Blu (5312) CTT
Comparing the strength and determinants of green-wave surfing across diverse ecosystems and multiple taxa of migratory ungulates
SPEAKER: Dr. Ellen Aikens, PhD student at the Wyoming Cooperative Fish and Wildlife Research Unit, University of Wyoming, USA.
ABSTRACT: In spring, it is hypothesized that migrating herbivores pace their movements with the progression of “the green wave” or the flush of nutritious plant green-up that sweeps across the landscape. Although there is a body of evidence to suggest that ungulates benefit from moving in response to heterogeneity in plant phenology, the first explicit test of the GWH found that red deer (Cervus elaphus) in Norway did not surf the green wave during migration. Instead, the majority of red deer "jumped" the green wave by moving rapidly from winter range to summer range without matching their movements with peaks in green-up. In contrast, my research demonstrates that migratory mule deer (Odocoileus hemionus) clearly surf the green wave, by matching their migratory movements with peaks in green-up. These conflicting findings beg the question, why do some migratory ungulates surf the green wave during migration, while others do not? In an attempt to answer this question, I am collaborating with a network of North American and European researchers to compile a multi-species, cross-continental dataset of ungulate movement.
HOST: Francesca Cagnacci