Understanding future threats to western rangelands: Modeling the performance of grazing strategies in the face of environmental change

Authors: TORELL, GREGORY - Texas A&M University; LEE, KATHERINE - University Of Idaho; STEELE, CAITI - New Mexico State University

Submitted to: Western Agricultural Economics Association
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/15/2018
Publication Date: 4/1/2019
Citation: Torell, G.L., Lee, K.D., Steele, C. 2019. Understanding future threats to western rangelands: Modeling the performance of grazing strategies in the face of environmental change. Western Economics Forum. 17(1):40-45.

Interpretive Summary: Understanding and modeling how climate change and stocking rate decisions will affect primary production of beneficial species is critical to maintaining rangeland health and sustaining future ranching on western rangelands. Managers must focus not only on maximizing economic returns from livestock grazing, but also how stocking decisions will impact inter-species competition between edible forage species, undesirable native species and non-native invader species. This piece discusses how climate change, species ecology, and human decision making simultaneously impact rangeland health and economic returns.

Technical Abstract: Rangeland ecosystems comprise 30% of the land area in the United States (Havstad et al. 2009), the health and resilience of which produce a variety of economic and social benefits. Rangelands are a dynamic resource; decisions made today affect range conditions over subsequent seasons, and conditions realized today are the product of past management decisions. Therefore, rangelands really must be managed over time. Historically, the economics literature on rangelands has focused predominantly on selecting livestock grazing strategies (namely stocking rates) to maximize economic net benefits. More recently, economic studies have incorporated insights from ecological research into models, adding ecological feedbacks to models as well as the effects of, for example, stochastic weather and invasive species. As changing climates alter the risks to rangeland ecology, through establishment and spread of invasive species and transition of rangelands away from native perennial grasses, the economic performance of existing livestock grazing strategies may need to be re-evaluated. While economists seek out grazing strategies that maximize profit, livestock producers and land management agencies often rely on rules of thumb, such as “take half, leave half” or “50% utilization” rule. The dynamic, economic, and ecological impacts that arise from rangeland managers using this rule of thumb are still poorly understood, especially under changing environmental conditions. So, the question arises: will continued use of the traditional 50% utilization rule of thumb benefit or harm the health of rangeland ecosystems and producers in the face of a changing climate and invasive plant species?