Abstract
The establishment and spreading of biological populations depends crucially on population growth at low densities. The Allee effect is a problem in those populations where the per capita growth rate at low densities is reduced. We examine stochastic spatial models in which the reproduction rate changes across a gradient so that the population undergoes a 2D-percolation transition. Without the Allee effect, the transition is continuous and the width of the hull scales as in conventional (i.e., uncorrelated) gradient percolation, . However, with a strong Allee effect the transition is first order and .
- Received 22 June 2010
DOI:https://doi.org/10.1103/PhysRevLett.106.128103
© 2011 American Physical Society