Reflections on niches and numbers

19 October 2019

Holt, Robert

Environmental factors control spatial distributions and local abundances in distinct – but overlapping – ways. Osorio-Olivera et al. (2019) examine when environments near the geometric center of a species’ ecological niche -- which they assume to be optimal for growth when rare --also harbor the greatest number of individuals on average at equilibrium, and when not. Transient dynamics, Allee effects and metapopulation dynamics can cloud this relationship. In this brief piece I sketch a number of further ways in which this relationship can break down, including asymmetry in the shape of the niche, spatial variation in density dependence, and nonlinear feedbacks with the environment.

10.1111/ecog.04828