Habitat use and spatial interactions of cattle, wild horses, mule deer, and California bighorn sheep in the Owyhee breaks of southeast Oregon

The objectives of this study were to quantify and describe: (1) the major plant communities and their distribution, (2) the distribution and movement patterns of large herbivores relative to water, topography, and plant communities, (3) the daily activity patterns of each herbivore, and (4) the borne range size of wild horse bands and studs on a 376 km² area in southeast Oregon. Distribution of plant communities about the area was indicative of a history of overgrazing and fire. Communities in low ecologic condition were associated with relatively level terrain and basin areas. Wild horses and bighorn sheep were year-around study area residents. Cattle occupancy was from April through October, and intensive deer use occurred from October through April. Deer movement to and from the area was correlated with, but probably not caused by cattle activities. Deer, however, preferred cheatgrass communities previously grazed by livestock. Ellipse estimates of home ranges for bands and studs averaged 28.3 and 25.8 km², respectively. Polygon estates for band and stud home ranges averaged 11.8 and 12.3 km², respectively. Home ranges of bands and studs overlapped substantially, and no territorial behavior was observed. Home range size showed a significant, but weak, negative correlation with water hole density. With the exception of bighorn sheep, habitat use by large herbivores was negatively correlated with increasing slope. Species order for progressively greater use of slopes was cattle, horses, deer, and bighorn sheep. Of the 4 herbivores studied bighorn sheep were the most restricted in distribution. Progressive rankings of greater spatial distribution were: bighorn sheep, cattle, horses, and deer. Patterns of resource use by large herbivores did not always conform to mathmatical expectations

Effects of grazing and drought on range grasses

Published June 1980. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalo

Abundances of Coplanted Native Bunchgrasses and Crested Wheatgrass after 13 Years

Crested wheatgrass (Agropyron cristatum [L] Gaertm) has been seeded on more than 5 million hectares in western North America because it establishes more readily than native bunchgrasses. Currently, there is substantial interest in reestablishing native species in sagebrush steppe, but efforts to reintroduce native grasses into crested wheatgrass stands have been largely unsuccessful, and little is known about the long-term dynamics of crested wheatgrass/native species mixes. We examined the abundance of crested wheatgrass and seven native sagebrush steppe bunchgrasses planted concurrently at equal low densities in nongrazed and unburned plots. Thirteen years post establishment, crested wheatgrass was the dominant bunchgrass, with a 10-fold increase in density. Idaho fescue (Festuca idahoensis Elmer), Thurber’s needlegrass (Achnatherum thurberianum (Piper) Barkworth), basin wildrye (Leymus cinereus [Scribn. & Merr.] A. Löve), and Sandberg bluegrass (Poa secunda J. Presl) maintained their low planting density, whereas bluebunch wheatgrass (Pseudoroegneria spicata [Pursh] A. Löve), needle-and-thread (Hesperostipa comata [Trin. & Rupr.] Barkworth), and squirreltail (Elymus elymoides [Raf.] Swezey) densities declined. Our results suggest that densities of native bunchgrasses planted with crested wheatgrass are unlikely to increase and that some species may only persist at low levels. The high recruitment of crested wheatgrass suggests that coplanting of some native bunchgrasses may be a viable way of avoiding crested wheatgrass monocultures when this species is necessary for rehabilitation or restoration.Keywords: Agropyron cristatum, Revegetation, Sagebrush steppe, Restoratio

Cheatgrass and its relationship to climate : a review

Published October 1979. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalo

Where eagles soar: Fine-resolution tracking reveals the spatiotemporal use of differential soaring modes in a large raptor

Unlike smaller raptors, which can readily use flapping flight, large raptors are mainly restricted to soaring flight due to energetic constraints. Soaring comprises of two main strategies: thermal and orographic soaring. These soaring strategies are driven by discrete uplift sources determined by the underlying topography and meteorological conditions in an area. High‐resolution GPS tracking of raptor flight allows the identification of these flight strategies and interpretation of the spatiotemporal occurrence of thermal and orographic soaring. In this study, we develop methods to identify soaring flight behaviors from high‐resolution GPS tracking data of Verreaux’s eagle Aquila verreauxii and analyze these data to understand the conditions that promote the use of thermal and orographic soaring. We use these findings to predict the use of soaring flight both spatially (across the landscape) and temporally (throughout the year) in two topographically contrasting regions in South Africa. We found that topography is important in determining the occurrence of soaring flight and that thermal soaring occurs in relatively flat areas which are likely to have good thermal uplift availability. The predicted use of orographic soaring was predominately determined by terrain slope. Contrary to our expectations, the topography and meteorology of eagle territories in the Sandveld promoted the use of soaring flight to a greater extent than in territories in the more mountainous Cederberg region. Spatiotemporal mapping of predicted flight behaviors can broaden our understanding of how large raptors like the Verreaux’s eagle use their habitat and how that links to energetics (as the preferential use of areas that maximize net energy gain is expected), reproductive success, and ultimately population dynamics. Understanding the fine‐scale landscape use and environmental drivers of raptor flight can also help to predict and mitigate potential detrimental effects of anthropogenic developments, such as mortality via collision with wind turbines.Publisher PDFPeer reviewe

Assessment of a global positioning system to evaluate activities of organic chickens at pasture

The aims of the present study were to assess the use of a global positioning system (GPS) monitoring device to evaluate the activities of organic chickens at pasture. Two hundred male birds from 2 strains (100 slow-growing and 100 fast-growing birds) were reared separately in 4 indoor pens (0.10 m2/bird), each with access to a grass paddock (10 m2/bird; 2 replications/ genotype). During the last week of age (from 73 to 80 d of age), the kinetic activity of chickens was monitored by behavioral observations (n = 20; focal bird sampling method) and a GPS (n = 10; Super Trackstick, Atex International, Route d'Esch, Luxembourg) equipped with a universal serial bus port for quick viewing on Google Earth's 3-D model, giving information concerning the date, hour, environmental conditions, and coordinates of monitored birds. Based on the focal bird sampling method, fast-growing birds tended to stay indoors rather than forage in the pasture, whereas slow-growing birds spent more time outdoors (P < 0.05). Moreover, visual observations confirmed GPS records, whereas slow growing birds were observed to perform more active behaviors stand less, and spend more time outdoors than indoors. Based on GPS tracks, slow-growing chickens covered an average daily distance of 1,230 m, whereas fastgrowing birds covered only 125 m. In conclusion, GPS appears to be a suitable way to evaluate the kinetic activity of chickens. We also concluded that locomotor activity, which requires a high energy consumption, is low in fast-growing birds compared with slow-growing ones, allowing the fast-growing birds to reallocate energy to productive traits

Seasonal Migration of Sika Deer in the Oku-Chichibu Mountains, Central Japan

Movements and seasonal home ranges of 6 GPS collared sika deer were investigated at the Oku-Chichibu Mountains, central Honshu, from April 2009 to March 2010. All deer migrated between discrete summer and winter home ranges. The linear migration distance ranged from 2.5 to 31.9 km. Mean elevation during the summer and the winter ranged from 980 to 1,782 m, and from 1,204 to 1,723 m, respectively. Two deer were upward migrants and 4 deer were downward migrants. Taking into consideration of the relatively small snow accumulation in the summer home range, the possibility of autumn migration to avoid deep snow is low. The percentage of steep slope in the winter home range was higher than that in the summer. Bamboo grass was not found in the summer home range, but was predominant in the winter home range. Road density decreased in the winter home range compared to the summer. Only 2 out of 6 deer stayed mainly in the wildlife protection area during the winter. Our results indicate that the autumn migration was affected by winter forage and human disturbance, thereby assured the survival of the deer during winter.ArticleMAMMAL STUDY. 37(2):127-137 (2012)journal articl

Prescribed fire effects on resource selection by cattle in mesic sagebrush steppe. Part 1: Spring grazing

Prescribed fire is commonly applied world-wide as a tool for enhancing habitats and altering resource-selection patterns of grazing animals. A scientific basis for this practice has been established in some ecosystems but its efficacy has not been rigorously evaluated on mesic sagebrush steppe. Beginning in 2003, resource-selection patterns of beef cows were investigated using global positioning system (GPS) collars for 2 years before and for 5 years after a fall prescribed burn was applied to mesic sagebrush steppe in the Owyhee Mountains of southwestern Idaho, USA. Resource-selection functions (RSF) developed from these data indicated cattle selected for lightly to moderately burned areas for all 5 postfire years. Cattle had been neutral towards these areas prior to the fire when their distribution was primarily affected by slope, sagebrush dominance, and distance to upland water. Resource-selection responses to the fire lasted 2-3 years longer than would be expected for fire-induced, forage-quality improvement effects. Although this is a case study and caution should be taken in extrapolating these results, if applied under conditions similar to this study, livestock producers and natural resource managers can likely use fall prescribed fire in the mesic sagebrush steppe to affect cattle resource-use patterns for 5 years postfire.KEYWORDS: Modeling, Livestock distribution, Habitat use, GPS tracking, Burning, Rangeland improvementThis is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/journal-of-arid-environments

The Relationship Between GPS Sampling Interval and Estimated Daily Travel Distances in Chacma Baboons (Papio ursinus)

Modern studies of animal movement use the Global Positioning System (GPS) to estimate animals’ distance traveled. The temporal resolution of GPS fixes recorded should match those of the behavior of interest; otherwise estimates are likely to be inappropriate. Here, we investigate how different GPS sampling intervals affect estimated daily travel distances for wild chacma baboons (Papio ursinus). By subsampling GPS data collected at one fix per second for 143 daily travel distances (12 baboons over 11–12 days), we found that less frequent GPS fixes result in smaller estimated travel distances. Moving from a GPS frequency of one fix every second to one fix every 30 s resulted in a 33% reduction in estimated daily travel distance, while using hourly GPS fixes resulted in a 66% reduction. We then use the relationship we find between estimated travel distance and GPS sampling interval to recalculate published baboon daily travel distances and find that accounting for the predicted effect of sampling interval does not affect conclusions of previous comparative analyses. However, if short-interval or continuous GPS data—which are becoming more common in studies of primate movement ecology—are compared with historical (longer interval) GPS data in future work, controlling for sampling interval is necessary