Data from: Harvest and density-dependent predation drive long-term population decline in a northern ungulate

The relative effect of top-down versus bottom-up forces in regulating and
limiting wildlife populations is an important theme in ecology. Untangling
these effects is critical for a basic understanding of trophic dynamics
and effective management. We examined the drivers of moose (Alces alces)
population growth by integrating two independent sources of observations
within a hierarchical Bayesian population model. This analysis used one of
the largest existing spatiotemporal datasets on ungulate population
dynamics globally. We documented a 20% population decline over the period
examined. Moose population growth was negatively density-dependent.
Although the mechanisms producing density-dependent suppression of
population growth could not be determined, the relatively low densities at
which moose populations were documented suggests it could be due primarily
to density-dependent predation. Predation primarily limited population
growth, except at low density, where it was regulating. Harvest appeared
to be largely additive and contributed to population declines. Our
results, highlight how population dynamics are context dependent and vary
strongly across gradients in climate, forest type, and predator abundance.
These results help clarify long-standing questions in population ecology
and highlight the complex relationships between natural and human-caused
mortality in driving ungulate population dynamics.