Network for Biological Invasions and Dispersal Research

MITACS Seminar at the University of New Brunswick, Fredericton

Thursday, 29 March, 2007,

Frithjof Lutscher

of the University of Ottawa

will speak on

Life in the flow: Persistence, Invasions and Competition in Rivers

3:00 PM, Tilley Hall 404

Abstract: Spatial patterns of community composition and species replacement in rivers emerge from complex interplays of hydrological, geochemical, biological, and ecological factors. While these processes are well understood locally, a mechanistic basis for large-scale emerging patterns is lacking. We study invasion speeds, range limits, and spatially-mediated coexistence in reaction-advection-diffusion equations for single species and two competitors in homogeneous and heterogeneous environments. We demonstrate that several variants of the "Fisher-speed" predict the respective invasion speeds. We show that emergent patterns have plausible spatial scales, given parameter estimates for certain algae (periphyton).