- Resilience-based management in rangelands implies maintaining desirable ecological states and avoiding thresholds to less desirable ones; however, the efficacy of resilience-based management depends upon several driving forces. These forces include management by those who depend upon rangelands for their livelihoods, the current state of ecological health of rangelands, and changing climate conditions. This study is unique in that it considers ranchers’ decisions when ranchers are faced with the possibility of sudden and permanent ecological health changes due to the confluence of multiple drivers. The term “at-risk phase” is often used to describe the phase of ecological health in which there is some likelihood of an ecological system crossing an ecological threshold (that is, transitioning to a reduced state of ecological health for the foreseeable future). This study investigates ranchers’ incentives to avoid crossing an ecological threshold during a drought given that their public land forage source is in the “at-risk phase”.
This study finds conditions under which it is profit-maximizing for ranchers to avoid crossing an ecological threshold by choosing to engage in a resilience-improving management action (e.g., resting some portion of their available forage, termed rest requirement). A model of a representative Eastern Oregon ranch experiencing drought looks forward, observing some probability that the resiliency of their public forage resource will be affected by drought and management, and decides whether or not to rest in the current year. Rest requirements of 25%, 50% and 75% of the typical number (outside of drought) of available animal unit months (AUMs) were considered. Post-threshold forage quantities available considered were 90%, 80% and 70% of typical.
Results show that it is profit-maximizing to rest and avoid crossing the threshold given the lowest rest requirement (25%) considered together with the higher losses that will occur if the threshold is crossed (80% and 70% of typical). It is also profit-maximizing to avoid crossing the threshold at the higher rest requirements if there are sufficiently large quantities of land available for lease while resting. For the 50% rest requirement, 80% of post-threshold forage available, and 50% probability of a drought that affects ecological resilience, 1093 AUMs would be required for the expected net present value (ENPV) of the rest decision to be above that of the rest decision in all years of the drought cycle. Grass banking/forage sharing and subsidies surface in this study as opportunities to reduce the probability of crossing ecological thresholds.
However, as this study recognizes, changes in rangeland health that are outside of the control of the rancher may still occur and may reduce the efficacy of programs that work to reduce the probability of crossing thresholds through ranch management. This may become a more important factor as climate variability increases. For example, in this study, if there is a 10% probability of a resilience-affecting drought occurring in each year of the drought cycle, a subsidy that makes it profit-maximizing to choose rest reduced the probability of crossing a threshold to nearly zero. However, given a 90% probability of a resilience-affecting drought in each year of the drought cycle, even with the subsidy, the probability of crossing a threshold could remain as high as 97%.
The role of subsidies, forage-sharing programs, research, and rancher education are evaluated in this study in light of possible rancher-caused and probabilistic drought-caused changes in ecological health states. Rancher impacts could be significantly reduced by these programs. For example, a rancher faced with the 50% rest requirement, 80% of typical forage available post-threshold, a three-year recovery time, and 50% probability of a drought that affects ecological resilience would see an 83% reduction in the expected financial impact from drought if they had access to 1093 AUMs of private lease land. That is, this ranch would see an increase in the ENPV of the income stream during drought of nearly $100,000 as the result of this opportunity to graze this land at typical private land forage prices.
This study concludes that protecting the health of rangelands, especially those negatively impacted by changes in climate, will require a multi-faceted approach. This approach includes rancher education and incentives in concert with resilience-based management. Resilience-based management that maintains or increases rangeland resistance to drought is shown to be integral to the effectiveness of efforts to protect ecological health through ranch management.