Water developments have been considered a fundamental tool for dispersing livestock and reducing livestock impact on riparian and aquatic habitats associated with perennial streams. Quantifying the efficacy of water developments has been difficult because of the need to continuously monitor water sources for the timing and intensity of use. The advent of global positioning system (GPS) tracking technology has largely overcome this hurdle and presented new research opportunities. We conducted a five-year study to quantify and evaluate the relative use of existing water developments by cattle on three extensive study areas in northeastern Oregon, United States. Ten randomly selected beef cows from herds grazing each study area were fitted with GPS collars recording animal positions at five-minute intervals throughout the grazing season. Cattle occupancy in 60 m (196.9 ft) buffers around water developments was determined monthly and annually. Use of water developments was contrasted with that of riparian zones. Cattle use of water developments varied substantially from site-to-site, month-to-month, and year-to-year. In some months, cattle watered exclusively from off-stream developments, and in others, cattle watered nearly exclusively from streams. Substantial differences in the relative use of individual water developments were also seen by season and year. Some developments received no use at all during the five-year study while others were visited frequently. Our results suggest off-stream water development is a useful managerial strategy, but careful placement is required to improve the likelihood that cattle will find and use these water sources and thus decrease their dependence and use of permanent streams and associated riparian areas. Key words: cattle riparian use-livestock water placement-off-stream water developmentsDevelopment of wells, reservoirs, springs, and seeps to control livestock distribution has been a primary focus of the rangeland management profession since its inception (Stoddart and Smith 1943; Sampson 1952; Williams 1954). Lack of available drinking water sources restricts the extent of landscape use by livestock (Bailey et al. 1996;Vallentine 2001). Establishment of new water sources at strategic locations can disperse cattle into areas where forages were previously under-utilized (Heady and Child 1994;Ganskopp 2001). Water development can thus simultaneously reduce daily travel distances and improve foraging efficiency of livestock (Valentine 1947). Development of off-stream water sources can also aid in making other tools (e.g., range riding and tree/brush control) for livestock distribution management more effective (Williams 1954; Clark et al. 2014). Water development may also reduce livestock use and consequent impacts on riparian areas, aquatic habitats, and stream water quality (Gillen et al. 1984;Vallentine 2001).Concentrated livestock use can damage riparian vegetation, stream banks, and channel morphology (Skovlin 1984;Kauffman et al. 1983aKauffman et al. , 1983bBe...

Stream and riparian health is a major concern for state and federal land management agencies that are charged with oversight of extensive land holdings in the mountain west of the United States. Several federal agencies in the 1980s and 1990s determined that livestock grazing had adversely impacted a majority of federal lands in this region. In response, management was changed on grazing allotments to focus on stream system health. Recent advanced global positioning system (GPS) logging capabilities, both accuracy and frequency/ duration of logging, coupled with rapidly developing geographic information system (GIS) analytical capabilities allowed evaluation of livestock use of streams and riparian zones on mountain rangelands. This study was undertaken to clarify spatiotemporal characteristics of cattle use of perennial streams and associated riparian areas under current US Forest Service (USFS) management and to suggest managerial strategies with the potential to maintain or improve riverine environments. We initiated a five year study in 2008 to evaluate the use by cattle of 30 m (98.4 ft) and 60 m (196.9 ft) buffers on permanent streams on three extensive study sites in northeastern Oregon. The three study sites cover 43,972 ha (108,700 ac) within a broader region 120 km (74.5 mi) north-south by 50 km (31 mi) east-west. Ten randomly selected cows from herds grazing each site were fitted with GPS collars that recorded position, date, and time at approximately five minute intervals throughout the grazing season. Nearly 3,750,000 cow positions were collected on the allotments during the study. The relative occupancy of cattle in buffers along both sides of perennial streams were determined on an annual and monthly basis by site. Each position was tagged with the date and time of occurrence. Relative use within 30 m of the stream varied substantially from site to site (0.74% to 2.54%), month to month (0.00% to 5.21%), and year to year (0.86% to 2.13%). In some months, GPS data indicated that watering was nearly exclusive from streams. In other months, stream use was low or nil, and watering was from water developments, small springs, seeps, puddles, or other source. Cattle preferred to access streams at specific locations where streambank slope, the lack of physical obstructions, and solid footing facilitated water access.

The spatial occupancy patterns and activity of cattle grazing three riparian pastures was investigated in northeastern Oregon using Global Positioning System (GPS) collars logging at 1-sec intervals. Cattle consistently selected plant communities as grazing areas that had forage in sufficient volume to meet their requirements and favored communities as resting areas that were dry and open. Cattle were stationary for more than 50% of the time in each pasture and consistently rested between dark and 04:00 hours. Interaction with stream channels was found to be 1-2% of total occupancy time and occurred on less than 10% of channel length. Cattle were indifferent or avoided channel areas relative to their area and, when in this zone, they spent most of their time moving not resting. Cattle did not prefer the stream bank zone and spent only 2% of their time in that zone. When occupied, the stream bank zone was used as a travel corridor to gain access to water or cross the channel to access other pasture areas. These results are in contrast with the general belief that cattle are a primary occupant of the stream bank/channel area; additional research is needed to define factors influencing cattle occupancy.