Abstract:
Climate change affects public land ecosystems and services throughout the American West and these effects
are projected to intensify. Even if greenhouse gas emissions are reduced, adaptation strategies for public lands
are needed to reduce anthropogenic stressors of terrestrial and aquatic ecosystems and to help native species
and ecosystems survive in an altered environment. Historical and contemporary livestock production—the
most widespread and long-running commercial use of public lands—can alter vegetation, soils, hydrology,
and wildlife species composition and abundances in ways that exacerbate the effects of climate change on
these resources. Excess abundance of native ungulates (e.g., deer or elk) and feral horses and burros add to
these impacts. Although many of these consequences have been studied for decades, the ongoing and
impending effects of ungulates in a changing climate require new ungulate management strategies for limiting
threats to the long-term supply of ecosystem services on public lands. Removing or reducing livestock across
large areas of public land would alleviate a widely recognized and long-term stressor and make these lands
less susceptible to the effects of climate change. Where livestock use continues, or where significant densities
of wild or feral ungulates occur, management should carefully document the ecological, social, and economic
consequences (both costs and benefits) to better ensure management that minimizes ungulate impacts to plant
and animal communities, soils, and water resources. Reestablishing apex predators in large, contiguous areas
of public land may help mitigate any adverse ecological effects of wild ungulates.
