Data from: Effects of predator recovery and climate change on the long-term demography of a flagship herbivore

Studies using spatial variation have explored the broad patterns of top-down and bottom-up forces in large herbivores. However, temporal changes in a population provide the most direct evidence for predicting future effects, and long-term studies spanning variation in top-down and bottom-up forces remain rare.</p> <p>We used 36 years of data on elk (<em>Cervus canadensis</em>) in the western United States in an integrated population model to test the effects of top-down (<em>Puma concolor</em> recovery) and bottom-up (drought) forces on pregnancy rates and age-based survival across a range of elk densities in the context of human harvest.

We then quantified the proportion of variance in population growth attributable to those forces relative to the influences of harvest, age-structure, and unmodelled variation in demographic rates.</p> <p>Both top-down and bottom-up forces had measurable effects on elk population dynamics, with puma recovery reducing survival in the first two years of life and drought reducing pregnancy probability and survival at all ages.