Modeling animal movement to manage landscapes

Managing rangelands with livestock grazing is a tool that can be applied to obtain vegetation management objectives. Animals utilize available resources, which vary in quantity and quality, across the landscape. Their movements are adjusted to the spatial and temporal heterogeneity of resource distribution. Controlling livestock distribution is fundamental to economically and ecologically sustainable livestock production systems on range and pasturelands. Having an understanding of animal movements in relations to scale will help develop strategies to better management livestock over entire landscapes. The research site was the Sierra Foothill Research and Extension Center (SFREC) in Marysville, California. The study was conducted on four annual rangeland pastures, average 25 hectares each. Two 20 cow herds grazed one pair of pastures one week and the pair the following week during January, March, April-May and August, during 2001, 2002, and 2003. Beef cow locations, turning angles, travel paths, and travel speed were determined with six cows in each of two herds of 20 cows equipped with global positioning collars. Individual measurements were recorded at five-minute intervals throughout the entire 5-7 days, recording longitude and latitude positions, date, time, elevation and a general measurement of horizontal and vertical activity. Cattle positions were analyzed to determine the fractal dimensions of movement and then modeled to determine what landscape attributes affected this movement. Domains of scale were detected whereas cattle movement at smaller ranges (< 40 meters) was less tortuous than at the larger ranges, 40 to 200 meters. Animal activities (grazing, resting and cruising) were also affected by landscape attributes. The research provided an understanding of how to apply spatial models of livestock movements that will aid in managing cattle distribution. Understanding how the ecological attributes and managerial options can affect distribution can lead to a better understanding of methods to manipulate cattle movement

History of Rangeland Management in California

On the Ground • Spanish colonists brought cattle to California when they landed in San Diego in 1769, with two hundred head of cattle arriving by overland routes. • Mexico, achieving independence, established rules to petition for land grants in California, paving the way for additional settlers by making land grants easier to obtain. • The Gold Rush resulted in cattle numbers quadrupling and sheep numbers increasing more than 60-fold between 1850 and 1860. • Multiple uses, such as agriculture crop production, impacted California rangelands. • Public policies now influence management of approximately 38 million acres of privately and publicly owned rangelands.The Rangelands archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform March 202

Ecology and Management of Annual Rangelands Series:History of Livestock Production

The Ecology and Management of Annual Rangelands Series is a 9-part online publication that provides owners and leasees of California rangelands with a comprehensive source of information pertinent to the management and enjoyment of these lands. This information will help you formulate and implement strategies for achieving your personal goals as a landowner.Range livestock production developed as an enterprise with the colonization of California by the Spanish and their formation of ranches or ranchos, and it expanded rapidly during early statehood. The development of improved animal management and range management practices ensured that the industry would continue its dominance in California agriculture throughout the twentieth century and into the twenty-first century

California’s Rangeland Water Quality Management Plan: An Update

The Rangelands archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform March 202

Estimation of the Requirement for Water and Ecosystem Benefits of Cow-Calf Production on California Rangeland

Beef production is perceived as using large amounts of water, and some studies recommend decreasing or ceasing meat consumption to decrease water use. Water footprints include different types of water, including green water (i.e., precipitation used for plant growth), blue water (i.e., drinking water and irrigation water used to grow alfalfa and irrigated pasture), and grey water (i.e., freshwater required for integrating water pollutants to a level accepted by water quality standards). A static model depicting blue and green water use for cow-calf production on California rangeland was developed. In this study, green water, which is sourced from rainfall and not available for another use, contributed the largest component to the total water footprint of cow-calf production at each location. It is important to consider the water use associated with beef production in the context of ecosystem services cattle provide to rangelands, such as preventing grassland conversion to shrub lands or woodlands, and the role that grazing cattle play in management of rangeland. © 2017 The Society for Range ManagementThe Rangelands archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information

Using Phenology to Optimize Timing of Mowing and Grazing Treatments for Medusahead (Taeniatherum caput-medusae)

The invasive annual grass medusahead (Taeniatherum caput-medusae [L.] Nevski) poses a substantial threat to the health and function of rangelands across the western United States. On rangelands containing other desirable annual grasses, selective control of medusahead is difficult as this invasive species has traits similar to those of desired species. One key trait that differs between medusahead and other annual grasses is the rate and timing of phenological development. In this study we define management states for medusahead on the basis of the patterns of variation of forage palatability and susceptibility of seed production to defoliation over phenological stages. We integrate these management states with field observations to model the rates and timing of phenology-based management states to identify when targeted grazing or mowing treatments are most appropriate using Dirichlet regression and multistate modeling. While defoliation at any phenological stage from V3 (boot) to R8 (milk stage) was effective in reducing medusahead seed head production, clipping after anthesis almost eliminated seed production. However, the observed decline in crude protein at this point (11-8%) suggests that the transition from R4 (emergence of awns) to R5 (anthesis) is also the point at which medusahead becomes both unpalatable and not adequately nutritious to livestock. As a consequence there was a window of 10 to 15 days when 90% or more of medusahead reproductive tillers are susceptible to grazing but could also support nutritional needs of cattle and sheep to prevent avoidance in diet selection. In contrast, the window of opportunity for mowing, on average, extended for about 35 days. In a given year, the timing in which different medusahead populations entered each phenological stage varied at both the landscape and pasture scale, which creates both challenges and opportunities in using grazing animals and other defoliation mechanisms to control medusahead. © 2017 The Society for Range Management.The Rangeland Ecology & Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information

Grazing Nassella: Maintaining Purple Needlegrass in a Sea of Aggressive Annuals

On the Ground • Purple needlegrass responds positively to early spring grazing that reduces competition from invasive annuals. • Rest during flowering allows for seed set and regrowth before soil moisture is depleted. • Dry season grazing can create a harsh soil surface microclimate during germination and seedling establishment of competing annuals the following year. • Purple needlegrass is not preferred by grazing livestock during the dry season, but high stock densities can increase its utilization.The Rangelands archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform March 202