You are here

Predicting the effects of climate change on cattle production in western U.S. rangelands

Date: September 13, 2018


Background

Cattle on western rangelands
Cattle on western rangelands
Cattle production capacity on western rangelands is potentially vulnerable to climate change through impacts on the amount of forage, changes in vegetation type, heat stress, and year-to-year forage variability. The researchers in this study projected climate change effects to rangelands through the year 2100 and compared them to a present-day baseline to estimate vulnerability of cattle operations. The analysis predicted: 

  1. an increase in forage quantity in northern regions;
  2. a move from woody dominance toward grassier vegetation types overall but with considerable variability between areas;
  3. a substantial increase in the number of heat-stress days across all regions beginning as early as 2020–2030;
  4. higher year-to-year variability of forage quantity for most regions. 

All four factors combined to predict declining grazing capacity in southwestern regions. In northern and interior regions of the West, the benefits of increased forage are mostly offset by increases in heat stress and forage variability. The predicted increased vulnerability of cattle production in the Southwest provides strong impetus for adaptation by livestock producers and public land managers in anticipation of these changes. This study can be used by range managers to begin to think about long-term planning and communication with stakeholders (such as grazing permit holders) about what kinds of conditions to expect in the future.

The four indicators used in this model were combined into one overall measure of vulnerability to climate change (graphic by M. Reeves).
The four indicators used in this model (forage quality, forage dependability, changes in vegetation type, and heat stress index) were combined into one overall measure of vulnerability to climate change (graphic by M. Reeves).

Key Findings

  • Potential climate change scenarios can be used to model the future vulnerability of cattle production in the western United States to warmer, drier conditions, and more variable conditions.
  • Under future climate change scenarios, the southwestern United States rangelands are projected to have a diminished capacity to support cattle due to greater moisture deficits and high temperatures that affect forage and stress livestock.
  • Projections for the northern rangelands are less clear cut, but the modeled effects of climate change indicate mostly neutral to positive changes for rangeland’s ability to support livestock due to warmer and possibly wetter conditions. 


Principal Investigators: 
Principal Investigators - External: 
Karen Bagne - Kenyon College
John Tanaka - Wyoming Agricultural Experiment Station