KEYWORDSCalifornia, home range, forage, mountain sheep, Ovis canadensis nelsmi population persistence, precipitation. SUMMARYWe compared sizes of home ranges and other ecological variables for female mountain sheep (Ovis canadensis nelsoni) inhabiting climatologically distinct areas in the Mojave Desert, California, USA. We also examined the relationship between size of home range and body size and age of mountain sheep. The pattern of precipitation was uni-modal in the more xeric Panamint Range, and bimodal at Old Dad Peak. Density of female sheep was about four times greater at Old Dad Peak than in the Panamint Range; Old Dad Peak also had more shrubs and perennial grasses than the Panamint Range. Home ranges and core areas were nearly twice as large in the Panamint Range than at Old Dad Peak, and females at Old Dad Peak were consistently nearer water. We detected no relationships between size of body or age and size of home-ranges for female mountain sheep. Females at Old Dad Peak foraged predominantly on perennial grasses and forbs, whereas those in the more xeric Panamint Range consumed mostly shrubs, perennial forbs, and succulents. In general, quality of forage was higher at Old Dad Peak than in the Panamint Range. Fecal nitrogen did not differ between areas in spring, but was higher in the Panamint Range during summer and autumn. We conclude that mountain sheep from the Panamint Range MAMMALIA, t. 67, n° 3 · 2003 · 385-401 385 Brought to you by | University of Georgia Libraries Authenticated Download Date | 5/28/15 6:47 PMOehlerM.W. et ai had larger home ranges because of lower availability and quality of forage, ostensibly a consequence ofthat precipitation regime. Use of cacti by mountain sheep in the Panamint Range likely enhanced the ability of females to increase the area in which they foraged in that depauperate and xeric environment. We hypothesize that pattern and amount of precipitation, and subsequent productivity of plants, affect the distribution of mountain sheep, and ultimately probabilities of persistence for populations of these mountain ungulates. RESUMELes dimensions des domaines des femelies de mouflons de montagne habitant des zones climatiques distinctes du desert Mohave (Californie, USA) ont ete comparees, ainsi que les relations entre la taille des territoires et le poids et Tage des animaux. Le patron de precipitations est unimodal dans la zone la plus seche, Panamint Range, et bimodal ä Old Dad Peak oil la densitc des femelles est environ quatre fois plus elevee. Cette derniere zone se caracterise egalement par une plus forte proportion de buissons et d'herbes vivaces et une meilleure qualite de fourrage. Les domaines et aires centrales de Panamint Range sont deux fois plus grands que ceux de Old Dad Peak oil les femelles sont nettement plus proches de l'eau. Aucune relation n'a pu etre mise en evidence entre la taille du corps ou Tage et les dimensions du domaine des mouflons femelles. Les femelles de Old Dad Peak se nourrissent surtout d'herbes vivaces et de forbs, tandis que ce...

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Wildlife and humans are increasingly competing for resources worldwide, and a diverse, innovative, and effective set of management tools is needed. Controlling abundance of wildlife species that are simultaneously protected, abundant, competitive for resources, and in conflict with some stakeholders but beloved by others, is a daunting challenge. Free-ranging horses (Equus caballus) present such a conundrum and managers struggle for effective tools for regulating their abundance. Controlling reproduction of female horses presents a potential alternative. During 2009–2017, we determined the long-term effectiveness of GnRH vaccine (GonaCon-Equine) both as a single immunization and subsequent reimmunization on reproduction and side effects in free-ranging horses. At a scheduled management roundup in 2009, we randomly assigned 57 adult mares to either a GonaCon-Equine treatment group (n = 29) or a saline control group (n = 28). In a second roundup in 2013, we administered a booster vaccination to these same mares. We used annual ground observations to estimate foaling proportions, social behaviors, body condition, and injection site reactions. We found this vaccine to be safe for pregnant females and neonates, with no overt deleterious behavioral side effects during the breeding season. The proportion of treated mares that foaled following a single vaccination was lower than that for control mares for the second (P = 0.03) and third (P = 0.08) post-treatment foaling seasons but was similar (P = 0.67) to untreated mares for the fourth season, demonstrating reversibility of the primary vaccine treatment. After two vaccinations, however, the proportion of females giving birth was lower (P <0.001) than that for control mares for three consecutive years and ranged from 0.0–0.16. The only detectable adverse side effect of vaccination was intramuscular swelling at the vaccination site. Regardless of vaccine treatment (primary/secondary), approximately 62% (34/55) of immunized mares revealed a visible reaction at the vaccine injection site. However, none of these mares displayed any evidence of lameness, altered gait or abnormal range of movement throughout the 8 years they were observed in this study. Our research suggests that practical application of this vaccine in feral horses will require an initial inoculation that may provide only modest suppression of fertility followed by reimmunization that together could result in greater reduction in population growth rates over time.