Search

Experiments investigating grazing systems have often excluded ranch-scale decision making, which has limited our understanding of the processes and consequences of adaptive management. We conducted interviews and vegetation monitoring on 17 ranches in eastern Colorado and eastern Wyoming to investigate rancher decision-making processes and the associated ecological consequences. Management variables investigated were grazing strategy, grazing intensity, planning style, and operation type. Ecological attributes included the relative abundance of plant functional groups and categories of ground cover. We examined the environmental and management correlates of plant species and functional group composition using nonmetric multidimensional scaling and linear mixed models. After accounting for environmental variation across the study region, species composition did not differ between grazing management strategy and planning style. Operation type was significantly correlated with plant community composition. Integrated cow-calf plus yearling operations had greater annual and less key perennial cool-season grass species cover relative to cow-calf − only operations. Integrated cow-calf plus yearling ranches were able to more rapidly restock following drought compared with cow-calf operations. Differences in types of livestock operations contributed to variability in plant species composition across the landscape that may support diverse native faunal species in these rangeland ecosystems. Three broad themes emerged from the interviews: 1) long-term goals, 2) flexibility, and 3) adaptive learning. Stocking-rate decisions appear to be slow, path-dependent choices that are shaped by broader social, economic, and political dynamics. Ranchers described having greater flexibility in altering grazing strategies than ranch-level, long-term, annual stocking rates. These results reflect the complexity of the social-ecological systems ranchers navigate in their adaptive decision-making processes. Ranch decision-making process diversity within these environments precludes development of a single “best” strategy to manage livestock grazing. [ABSTRACT FROM AUTHOR]

Rangelands of the western Great Plains of North America are complex social-ecological systems where management objectives for livestock production, grassland bird conservation, and vegetation structure and composition converge. The Collaborative Adaptive Rangeland Management (CARM) experiment is a 10-year collaborative adaptive management (CAM) project initiated in 2012 that is aimed at fostering science-management partnerships and data-driven rangeland management through a participatory, multistakeholder approach. This study evaluates the decision-making process that emerged from the first 4 yr of CARM. Our objectives were to 1) document how diverse stakeholder experiences, epistemologies, and resulting knowledge contributed to the CARM project, 2) evaluate how coproduced knowledge informed management decision making through three grazing seasons, and 3) explore the implications of participation in the CARM project for rangeland stakeholders. We evaluated management decision making as representatives from government agencies and conservation nongovernmental organizations, ranchers, and interdisciplinary researchers worked within the CARM experiment to 1) prioritize desired ecosystem services; 2) determine objectives; 3) set stocking rates, criteria for livestock movement among pastures, and vegetation treatments; and 4) select monitoring techniques that would inform decision making. For this paper, we analyzed meeting transcripts, interviews, and focus group data related to stakeholder group decision making. We find two key lessons from the CARM project. First, the CAM process makes visible, but does not reconcile differences between, stakeholder experiences and ways of knowing about complex rangeland systems. Second, social learning in CAM is contingent on the development of trust among stakeholder and researcher groups. We suggest future CAM efforts should 1) make direct efforts to share and acknowledge managers’ different rangeland management experiences, epistemologies, and knowledge and 2) involve long-term research commitment in time and funding to social, as well as experimental, processes that promote trust building among stakeholders and researchers over time. [ABSTRACT FROM AUTHOR]

Highlights: [•] Heavy stocking makes cattle more sensitive to weather patterns. [•] Kentucky bluegrass invasion changed cattle response to seasonal weather patterns. [•] Results have much utility for decision support tools. [Copyright &y& Elsevier]

Abstract: Quantifying the effects of seasonal temperature and precipitation on cow–calf production on rangelands is challenging, as few long-term (>20yrs) studies have been reported. However, an understanding of how seasonal weather inconsistency affects beef production is needed for beef producers to better manage their herds on native rangelands to minimize enterprise risk with respect to climatic variability. Cow–calf beef production data collected at the USDA-ARS High Plains Grasslands Research Station near Cheyenne, WY, USA from 1975 to 2012 were tested using model averaging for effects of spring (April–June) and summer (July–September) temperature and precipitation, as well as prior winter (October–March) and prior growing season (April–September) precipitation on beef production. Two breeds were used at different times during the study period (Herefords from 1975 to 2001 and a Red Angus×Charolais×Salers cross from 2003 to 2012; there was no grazing in 2002) and examined separately to test for differential effects of seasonal weather by breed. Herefords were more sensitive to seasonal weather patterns than the crossbreds, with Hereford pair total beef production showing the largest effect sizes and Hereford cows showing the highest R 2 value (0.66) among models. Wet springs and wet winters particularly increased Hereford beef production in this northern mixed-grass prairie, whereas beef production from the crossbreds did not show any weather effect patterns. The model structure used maximizes utility of these data to be built into decision support tools to help ranchers optimize stocking rates and minimize enterprise risk in advance of the grazing season. [Copyright &y& Elsevier]

• Toxic plants negatively affect livestock production but detection is difficult. • Fecal DNA (fDNA) metabarcoding technology is an emerging but untested method. • We quantified diets for 2 Rambouillet flocks in western Wyoming, USA with fDNA. • 3 toxic plants and 6 lichens identified; M. species in diets concurrently. • fDNA challenges include discerning between species and georeferencing is required. Toxic plants can negatively affect livestock production due to acute or chronic toxicosis. Detecting toxic plants in free-ranging animal diets has been a persistent challenge as toxicosis may only be noted with acute toxicity and subsequent mortality – but not necessarily when signs are sub-clinical. New fecal DNA (fDNA) metabarcoding technology can quantify diet composition of free-ranging livestock without the need for gathering/handling animals or the use of invasive procedures to determine hepatotoxicity and could inform more proactive toxic plant management. We quantified sheep diet composition in extensive rangeland environments with the specific aim of estimating toxic plant consumption using fDNA technology. Diets for 2 Rambouillet flocks in western Wyoming, USA [HSC flock: 1,800 ewes (+ lambs), 3,328 ha allotment, 1,829–2,438 m elevation; SBT flock: 1,010 ewes (+ lambs), a 4,262 ha allotment, 2,438–3,048 m elevation] were quantified with fDNA in the 2017 summer months. A total of 93 plant species were identified. HSC diets were dominated by grasses (51%) and forbs (31%) but SBT diets were dominated by forbs (42%) with minor contributions from shrubs (14%) and grasses (13%). Three potentially toxic species were identified: Short's milkvetch (Astragalus shortianus), chokecherry (Prunus virginiana), and larkspur (Delphinium species). In addition and problematically, one Operational Taxonomic Unit (OTU) could be attributed to either 3 different selenium accumulating plant species in the Asteraceae family or the toxic plant deathcamas (Zigadenus venenosus var. gramineus) in the Liliaceae family, was also detected. Six genera of lichens were also identified in diets. Challenges with fDNA technology include (1) an OTU might be shared by several plant species, and (2) reconciling fDNA laboratory data with georeferenced plant data is necessary to ensure correct interpretations. Finally, fDNA could be used for adaptive grazing management to enhance livestock nutrition and as a proactive tool to increase awareness of potential toxicosis problems before clinical signs or mortalities occur. [ABSTRACT FROM AUTHOR]