EVALUATION OF LOW-STRESS HERDING AND SUPPLEMENT PLACEMENT TO MODIFY CATTLE DISTRIBUTION AND IMPROVE PRONGHORN HABITAT

THE STORY IN BRIEF: A study was conducted to determine if prescribed cattle grazing could be used to improve pronghorn habitat without fencing. Seven of 87 cows were tracked with global positioning system (GPS) collars for 6 weeks in the summer of 2006. These cows were herded to 20-ha (50-acre) target areas that were at least 2.2 km (1.4 miles) from water and contained decadent vegetation. Cows were herded daily for half of the study and weekly the remainder of the study. Low-moisture block supplement was placed in target areas. Twenty pronghorn were fitted with very-high frequency (VHF) radio collars and visually observed from May 2006 through December 2006. Cattle spent more time (P = 0.002) within target areas (14.9 ± 1.8%) than control areas (0.3 ± 1.8%). Fecal abundance of cattle was greater (P = 0.06) within the target areas than in the control indicating higher preference for the target areas. Daily herding was more successful than herding once per week (P = 0.05) in holding cattle within the target areas. Cattle readily stayed in or near target areas during the first 3 weeks when the study area faced severe drought conditions. During the second 3 weeks, the study site received above average rainfall, and cattle spent less time near target areas. The abundance of scarlet globe mallow was greater in target areas than within the control (P = 0.09). Annual forb cover was higher within the target areas that were treated during drought conditions and the grazing impact was greater. Distribution of pronghorn was influenced by target areas. Pronghorn pellet groups were more abundant in target areas (P = 0.125) in 5 of 6 comparisons with control areas, which also suggests that pronghorn spent more time within the target areas than in the controls. THE PROBLEM: Livestock distribution in extensive or rugged pastures is often uneven with many areas receiving little grazing. Forage in underutilized areas becomes decadent and is avoided by wildlife. Pronghorn prefer areas with greater abundances of forbs and other high quality forage. Wildlife managers traditionally use prescribed fire, herbicides, or mechanical treatments to improve habitat. Prescribed livestock grazing can also be used to improve wildlife habitat, but it is difficult to focus cattle grazing without extensive fencing and water development.