For conservationists working with ranchers to implement grazing practices that promote biodiversity, a new study in the journal Rangeland Ecology and Management shows that these well-intentioned efforts can hurt long-term profits.
From a conservation perspective, the higher quality grasslands that arise from less intensive grazing are desirable for numerous reasons - they potentially have higher plant diversity, provide better wildlife habitat, sequester more carbon, etc. Some in the conservation field have assumed that these environmental objectives align with ranchers' economic interests.
"Conventional wisdom suggests that grazing livestock over long periods of time on lower condition rangeland is not biologically or economically sustainable," the study authors write. However, as their study findings show, ranchers earn greater sustained profits over time from more intensive grazing that leaves the rangeland in a poorer condition.
Barry Dunn from Texas A & M and fellow researchers from South Dakota State University looked at the results from a 34-year trial in which cattle were managed on 6 separate experimental pastures in South Dakota under 3 different management regimes. For each paired pasture, the cattle were grazed at variable stocking rates from year-to-year to maintain the grassland at either "low-fair," "good," or "excellent" condition.
The researchers measured the hypothetical costs and income from each pasture over the 34-year period and found that the pastures in "excellent" condition earned less sustained profit over time than those in either "fair" or "good" condition. In addition, over the course of the study net profit increased steadily in both the "fair" and "good" condition pastures while it remained constant for the "excellent" sites.
These results may help explain why the "generally observed rancher behavior is to maintain rangelands and pasturelands in condition classes lower than recommended."
As the study authors note, when grazing intensifies in the northern mixed-grass prairie region, the vegetation shifts from midgrass to shortgrass dominated communities. Conservationists generally prefer midgrass communities for their increased plant diversity and superior wildlife habitat.
However, as these study findings show, if conservationists want to promote greater mixed-grass prairie, ranchers may need to be compensated to shift their economic incentives away from more intensive grazing.
--Reviewed by Rob Goldstein
Dunn, B., Smart, A., Gates, R., Johnson, P., Beutler, M., Diersen, M., & Janssen, L. (2010). Long-Term Production and Profitability From Grazing Cattle in the Northern Mixed Grass Prairie Rangeland Ecology & Management, 63 (2), 233-242 DOI: 10.2111/REM-D-09-00042.1