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T he reintroduction of wolves into their historical ranges in the North American Rocky Mountains and areas of the southwestern United States is possibly one of the most ambitious ecosystem- restoration efforts of the recent past. This initiative has been controversial and has stimulated considerable debate among concerned stakeholders about the feasibility of harmoniz- ing multiple land-use demands when preservation of a large predator becomes a central management goal. In many areas, ranching has taken center stage of this debate as ranchers and land managers seek to develop sustainable ways to manage livestock on landscapes with wolves.

Conserving large carnivores throughout the world will often require that they share the landscape with livestock. Minimizing depredations and increasing tolerance by livestock producers will be critical for conservation efforts. To investigate factors influencing calf mortality and producer detection rates (i.e., number of livestock killed by predators, found by producers, and correctly classified as to cause of death), we monitored radio-tagged domestic calves at two sites in the Mexican wolf recovery area (East Eagle [EE] and Adobe Ranch [AR]). Study areas differed in grazing practices, density of predators (mountain lions, black bears, coyotes, and Mexican wolves), and amount of effort spent monitoring cattle. We radiotagged 618 calves over 3.5 years, and 312 calves over 2 years on the EE and AR, respectively. The overall proportion of radioed calves that died was higher on the EE (6.5%) than on the AR (1.9%). Predators (especially mountain lions) accounted for 85% of mortality on the EE and 0% on the AR. Calves selected by predators were on average 25 days younger than the surviving cohort. Our results indicate that year-round calving, especially in areas with high predator densities, are subject to higher losses primarily because calves are exposed to mortality agents for longer periods of time rather than having higher natural rates of mortality. We found a significant difference in producer detection rates between study sites, likely due to differences in the intensity of monitoring cattle between sites. On the EE, the producer detected 77.5% of mortalities and on the AR, the producer detected 33% of mortalities. Our results support changing husbandry practices to limit calving to a seasonal endeavor and that performance payment may be a better compensation strategy than ex post compensation schemes. Published by Elsevier Ltd.

Vigilant behavior in wild ungulates is critical to guard against predation. However, few studies have examined vigilant behavior in domesticated ungulates. Considering the expansion of large predator populations, understanding vigilant behavior and factors that influence it will help with the management of livestock. We observed adult female cattle (Bos taurus L.) in open-range conditions where large predators (wolves [Canis lupus L.] and mountain lions [Puma concolor (L.).]) were common threats during summers of 2005 and 2006 in eastern Arizona. This study was designed to determine 1) to what extent cattle exhibit vigilant behavior compared to published data on wild ungulates, 2) whether predation events influence vigilance rates of cattle, and 3) whether social and environmental factors affect vigilance of cattle. Cattle exhibited vigilant behavior (3% ± 0.19%) during peak foraging periods, but at a lower rate than wild ungulates. Cows with calves were more than twice as vigilant (4.5% ± 0.46%)...

In the southwestern United States, local weed management programs are increasingly important in weed prevention and control; however, little is known about the effectiveness of different local approaches to weed management. We surveyed coordinators of 53 local weed management programs in Arizona, Colorado, New Mexico, and Utah to determine how 4 key program attributes (interagency coordination, volunteer participation, regulatory authority and enforcement, and the state in which the program was located) were related with 4 performance measures: weed control, public education and outreach, weed monitoring, and integrated weed management. Based on the responses of 42 program coordinators (79%) we found that 1) weed programs that coordinated their activities with other organizations and those with citizen volunteers conducted more monitoring, but programs that did not coordinate or use volunteers treated more of their infested acreage; 2) programs that used a light-handed regulatory approach conducted more weed control than those with more punitive enforcement regimes or no enforcement authority; and 3) Colorado programs conducted more outreach and education than did programs in the other 3 states. Thus, although volunteer involvement and interagency coordination contributed to the performance of the local weed programs studied, particularly in monitoring, they have not compensated for the lack of locally enforceable weed regulations or adequate funding. Successful weed management in southwestern United States will require adequately funded, locally adapted approaches supported by locally enforceable weed regulations.

Many grazing-management challenges stem from poor livestock distribution resulting in overuse of some areas and low utilization of others. Managing livestock-distribution patterns requires knowledge of pasture characteristics and animal behavior patterns. Behavioral patterns result from recognizable processes that include inherited attributes, individual and social learning systems, cue-consequence specificity, predispositions toward novel stimuli, and spatial memory. Through these behavioral mechanisms, animals form and revise preferences and aversions for specific locations in their foraging landscape. To accomplish habitat selection, domestic herbivores use sight and sound cues to seek and return to high-quality foraging locations. Nested within habitat selection are learned diet preferences and aversions by which ungulate herbivores associate taste with positive or negative postingestive feedback. The deliberate and careful modification of animal attributes and habitat characteristics could yield options for adaptive rangeland management. In this article, we describe the basic principles that underlie how animals make decisions about where to forage and how long to stay in a particular habitat. We also suggest management practices designed to modify animal behavior and alter habitat-use patterns.

We determined the cattle distribution patterns of dams (and foster dams) and their offspring while grazing a 1030 ha (about 3 km by 5 km) allotment during the summers of 1990–1993. Our primary objective in this 4-year field study was to determine whether yearling and adult offspring (and foster offspring) would return to the initial locations and associated habitat types that they were exposed to by their dams (or foster dams) early in life. We observed the dams' offspring for four consecutive summers (1990–1993) and the foster-dams' offspring for 3 consecutive summers (1991–1993). Cross-fostering was conducted to learn the relative importance of natural dams vs. foster dams as social models in influencing distribution patterns of offspring. Offspring were reared mostly in two different locations on the allotment by their dams or foster dams. Centroid analyses indicated that offspring in all 4 groups remained near the general location where they were reared as calves when they returned to the allotment as older animals (mean 0.5 to 1.2 km from dams' or foster dams' centroid). Peers apparently attenuated the dams' (and foster dams') influence on location and habitat use when offspring were yearlings. The effect of peers was manifested by an increase in distance from dams' or foster dams' centroid, and by a higher association index among yearlings, both of which reflected the collective experiences of offspring in the peer groups. Drought weakened the dams' and foster dams' influence on location and habitat use as water became scarce near their centroids, but drought amplified the dams' and foster dams' influence when water was not limited near their centroids. By the final year of the study, offspring in 3 of the 4 groups monitored were within 0.7 km from the dams' or foster dams' centroid (offspring in the fourth group were within 1.1 km from the foster dams' centroid). Collectively, our results suggest that experiences early in life affected cattle distribution, and that distribution at any point in time was a ‘snapshot’ of ongoing behavioral changes that were developing according to each individual's antecedent experiences and current environmental and social conditions. These results support the ‘working hypotheses’ that herding, selective culling, and water and shade development are important management techniques that can enhance dispersion and decrease use of sensitive areas on rangelands (e.g., riparian areas).

We evaluated fecal nitrogen (FN) and fecal phosphorus (FP) concentrations as indicators of different dietary nitrogen (DN) and dietary phosphorus (DP) levels fed to 11 penned, white-tailed deer does (Odocoileus virginianus) during summer 1985. We fed deer pelleted rations containing 2 levels of DN (2.64 and 1.18%) or DP (0.49 and 0.30%) during 2 consecutive, 16-day trials. We collected fecal pellets from each animal during the last 6 days of each trial. Pooled mean FN concentrations for corresponding high and low DN levels were as follows: total FN = 2.26 and 1.45% (P = 0.003), neutral detergent FN = 0.60 and 0.39% (P = 0.019), and metabolic FN = 1.67 and 1.06% (P = 0.001). Pooled mean FP concentrations for corresponding high and medium DP levels were as follows: total FP = 1.23 and 0.44% (P = 0.002), neutral detergent FP = 0.12 and 0.10% (P = 0.022), and endogenous FP = 1.11 and 0.33% (P = 0.002). Under controlled conditions FN and FP concentrations can be used to discern relatively large differences in DN and DP levels of whitetailed deer. J. WILDL. MANAGE. 54(3):383-389 Nutrient levels of hand-collected forages have been used as indicators of dietary quality (Cook 1964), but this is generally an unreliable method for determining diet quality of free-ranging ungulates (Theurer et al. 1976) due to the apparent ability of ungulates to select the most nutritious forage available (Swift 1948). Esophageal fistulization is usually impractical for studying diet quality of free-ranging wild ungulates (Leslie and Starkey 1985) and, moreover, is unsuitable for DP assessment due to salivary phosphorus (P) contamination (Holechek et al. 1985). Blood samples require manual restraint or death of animals and, given the complex effects of homeostatic regulation of mineral metabolism, blood P concentrations may not be sufficiently sensitive to assess P status (Underwood 1981). The use of fecal nutrient levels to study diet quality may be a feasible noninvasive alternative to other techniques that require disturbance, stress, or death of wild ungulates (Leslie and Starkey 1985). Researchers have used fecal nutrient levels to predict dietary nutrient levels in elk (Cervus elaphus) (Mould and Robbins 1981, Leslie and Starkey 1985), black-tailed deer (Odocoileus hemionus columbianus) (Leslie and Starkey 1985, Mubanga et al. 1985), white-tailed deer (Jenks et al. 1989, Leslie et al. 1989), moose (Alces alces) (Leslie et al. 1989), and domestic livestock (Belonje and Van den Berg 1980a,b; Holechek et al. 1982, 1985). The advantages (Leslie and Starkey 1987) and disadvantages (Hobbs 1987) of FN as an indicator of DN in free-ranging deer diets have been discussed, but little controlled research has been conducted to determine the utility of using fecal indices for nutrient assessment of wild ungulate diets, particularly for white-tailed deer. Leslie and Starkey (1987) argued for continued research toward refining the use of fecal indices to measure the quality of wild ungulate diets. We conducted a controlled study involving 2 consecutive feeding trials to determine whether FN and FP concentrations could be used to detect differences in DN and DP levels fed to penned, white-tailed deer does. We thank C. Schreiner IV and the Y. O. Ranch employees of Mountain Home, Texas, for their kindness, cooperation, and generous use of study pens and other facilities. Critically constructive comments on the manuscript were provided by T. J. DeLiberto, S. Demarais, and F. C. Bryant. We are grateful to E. A. Howery for assistance with data collection and tabulation and to G. R. Scott and N. C. Jordan for lab assistance. Financial support was provided by the Caesar Kleberg Foundation for Wildlife Conservation and Texas Tech University. This is publication T-9577 of The College of Agricultural Sciences, Texas Tech University, Lubbock. 'Present address: Range Science Department, Utah State University, Logan, UT 84322-5230.