Understanding the response of wide-ranging
animals to a changing climate is a central and pressing
question in ecology. This is especially true in the Arctic,
which is warming more rapidly than any other place on Earth.
Perhaps the most important to the ecology of the far north is
caribou and reindeer (Rangifer tarandus spp.) - a keystone
herbivore and prey species that is also of immeasurable
material and spiritual value to human communities. Via their
iconic long-distance mass migrations - the longest terrestrial
migrations on Earth - caribou link the "browning" boreal
forest - which is losing biomass to increasing fires, disease
and development - to the "greening" tundra biomes, where
vegetation is shrubifying and expanding. Worryingly, most wild
populations of caribou and reindeer are also declining - in
some places precipitously - but definitive mechanistic links
between climate and caribou populations remain mysterious.
I will present a suite of long-term, large-scaled studies on
the environmental drivers of caribou movements and
populations, obtained from satellite tracking collars on
animals across Alaska, Yukon, Northwest Territories and
Nunavut. Armed with novel modeling techniques, our analyses
have yielded insights into migration timing, seasonal ranging,
calving behavior, sociality and mortality. All of these are
highly variable and dynamic within years, across years, and
across populations and are all influenced - often in
unexpected ways - by climate and weather. The results point
towards specific ecological pathways by which climate change
impacts caribou, while also revealing the complex and adaptive
pulse of animal movements across a dynamic seasonal landscape
at an unprecedented scale.
About the Speaker:
Dr. Elie Gurarie - is a quantitative
wildlife ecologist who combines empirical and theoretical
approaches in the service of answering questions related to
habitat use, spatial distributions, cognition, and population
dynamics of animals in dynamic and heterogeneous environments.
He obtained his BS in Physics from Case Western Reserve
University in Cleveland, OH, a master's in environmental
geosciences from the University of Marseille in France, and a
PhD in Quantitative Ecology and Resource Management from U.
Washington, Seattle. He has conducted post-doctoral research
at the University of Helsinki in Finland, at the Marine Mammal
Laboratory - NOAA, Seattle, and the Universities of Melbourne
and Queensland in Australia prior to joining the Department of
Biology, U. Maryland - College Park as a research scientist.
He is currently a visiting faculty fellow at the Department of
Forest and Wildlife Ecology, U. of Wisconsin, Madison.