Vlastimil Křivan
Faculty of Science, University of South Bohemia, and Biology Center CAS, Ceske Budejovice
Competition driven spatial animal distribution
[When and where]
In my talk I will discuss the effect of competition on species distribution and population dynamics in heterogeneous environments consisting of two or more patches. I will assume that dispersal is density dependent and in direction of increasing fitness. When the per capita population growth rate is negatively density dependent, this means that individuals disperse to patches where intra-/inter-specific competition is weaker. For a single species the resulting distribution is known as the Ideal Free Distribution (IFD). In fact, the IFD is an evolutionarily stable strategy of the underlying Habitat Selection Game. The single species IFD was extended to two competing species in two patches using a two-species ESS. In contrast to the single species distribution, the resulting two-species distribution may not be unique. At high population densities, it can lead to complete species segregation with species occupying different patches. Such competition driven species separation has been called ``ghost of competition past’’. Then I will study consequences of the IFD on the Lotka-Volterra population dynamics of two competing species. I will show that fast adaptive animal dispersal can destabilize a stable population equilibrium leading to fluctuations in population densities. I will also discuss apparent competition and I will show that fast directed density-dependent dispersal of consumers among two resource patches promotes species coexistence when compared with density-independent dispersal.
Invited talk Mini-symposium 2
Updated May 13, 2015, by Minus