Adapting to Climate Change on Western Public Lands: Addressing the Ecological Effects of Domestic, Wild, and Feral Ungulates

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 management strategies for limiting their 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.

Western Land Managers will Need all Available Tools for Adapting to Climate Change, Including Grazing: A Critique of Beschta et al.

“…The research was necessary to determine appropriate timing of grazing and numbers of livestock. These changes have been implemented over large areas, as Beschta et al (2013) show in their Figure 2, with livestock numbers on Bureau of Land Management (BLM) land dropping by 50 % from the 1950s to 2000s (also see Wagner 1978). Yet these authors use many of these decades' old studies to argue that current levels of grazing are inappropriate when in fact the criticism does not apply to landscapes now under accepted grazing practices and stocking rates.…”

“…The impacts of grazing depend on the timing, intensity, and frequency, as well as, type of animal (Heitschmidt and Stuth 1991). The impacts of grazing can be negative as Beschta et al (2013) point out. But there are examples of positive effects of grazing on landscape diversity and habitats of individual species (Austin et al 1994;Clark et al 2000;Fuhlendorf et al 2006), thus broad generalizations do not capture the impacts of grazing, even without the complicating effects of climate change.…”

“…Chaney et al 1993;Wyman et al 2006). Given the emphasis of Beschta et al (2013) on riparian areas and wildlife habitat, it is interesting to note that position statements by the American Fisheries Society (Armour et al 1991, current version available on American Fisheries Society website) and The Wildlife Society (2010) do not advocate removing livestock from western rangelands. Rather the position statements recognize that informed management and the use of appropriate science can result in a positive outcome for a variety of rangeland resources.…”

“…We suggest that Beschta et al (2013) have selected individual studies and parts of studies which support their central thesis rather than presenting a complete synthesis of the topic. For example, they cite publications by Love (1959) and Blackburn (1984) to support their observation that ''livestock have had numerous and widespread negative effects to western ecosystems.''…”

“…Keywords Grazing Á Public lands Á Climate change Á Riparian areas Beschta et al (2013) suggest that grazing on public lands (by livestock, feral herbivores such as ''wild'' horses and burros, and native ungulates) should be greatly reduced or eliminated as a means of improving the capacity of native vegetation communities to cope with climate change. We dispute the notion that eliminating grazing will provide a solution to problems created by climate change, and focus on three primary points: (1) grazing is a complex ecological process and a single recommendation (e.g.…”