Mechanisms of Population Persistence for a Rare Endemic Plant

Small populations are particularly susceptible to extinction, and the ways that these populations persist over time is a puzzle in conservation and ecology. Understanding the mechanisms that increase the chances for small populations of rare species to persist is important to global biodiversity. Desert yellowhead is a rare endemic plant that occurs in only two small populations in central Wyoming, USA. These populations appear to have persisted with remarkable stability; spatial asynchrony in growth among subpopulations results in a portfolio effect, and negative density dependence allows the population to recover from low numbers. In the future, warmer temperatures and potentially increased variation in precipitation could diminish these stabilizing mechanisms. Photo credit: Reilly Dibner. These photographs illustrate the article “Multiple Mechanisms Confer Stability to Isolated Populations of a Rare Endemic Plant” by Reilly R. Dibner, Megan L. Peterson, Allison M. Louthan, and Daniel F. Doak published in Ecological Monographs. https://doi.org/10.1002/ecm.136