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Abstract ContextWildlife biologists accumulate large quantities of images from remote cameras, which can be time- and cost-prohibitive to archive and analyse. Remote-camera projects would benefit from not setting cameras longer than needed and not analysing more images than needed; however, there is a lack of information about optimal deployment time required for remote-camera surveys to estimate ungulate abundance. AimsThe objective was to estimate abundance of adult females in a population of Rocky Mountain bighorn sheep (Ovis canadensis canadensis) in Utah, USA, from 2012 to 2014, and determine whether this type of study can be conducted more efficiently. Because females are the most important cohort for population growth, remote cameras were set at three water sources and mark–resight models in Program MARK were used. MethodsWe compared estimated abundance of collared and uncollared females by number of days cameras were set using 31 replicated abundance estimates from each year starting 1 July. Each replicated estimate used a different number of days and photographs from a 62-day sampling period (1 July to 31 August). Key resultsAbundance estimates ranged from 44 to 98 animals. Precise estimates of abundance, however, were obtained with only 12 days of sampling in each year. By analysing only 12 days of images rather than 62 days in all years, the estimated mean of 58 adult females would have changed by only 7 individuals (±4 individuals, range=3–10 animals), the s.e. would have increased by a mean of only 4 individuals (±1.6, range=2.0–5.2 individuals) and a mean of only 18% (±10.5%, range=8–29%) of images would have been analysed. Across the study, analysis of >23000 (>80%) images could have been avoided, saving time and money. ConclusionsThe results indicate that an asymptotic relationship exists between estimated abundance of female bighorn sheep and remote-camera deployment time. ImplicationsThe mark–resight methods used in the present study would work for other ungulates in which individuals are radio collared or marked using remote cameras set at water sources, trail crossings or mineral licks. These findings can help researchers reduce cost of setting, servicing, archiving and analysing photographs from remote cameras for ungulate population monitoring.

Abstract ContextTranslocation of wildlife has become common practice for wildlife managers charged with management of animals on increasingly modified landscapes. Mule deer (Odocoileus hemionus) is a species of great interest to the public in western North America, and individuals of this species have been translocated several times, but little has been done to document the outcomes of those translocations. AimOur objective was to evaluate the movement, space use and site fidelity of translocated female mule deer in comparison with resident female deer in Utah, USA. MethodsIn January and March 2013, 102 translocated and 50 resident female mule deer were captured and fitted with radio-transmitters. Movement distances, home range sizes and seasonal range sizes were compared, as well as site fidelity between translocated and resident deer. Key resultsMean distance moved and mean annual home range size were significantly larger for translocated than resident deer in 2013, but not in 2014. Translocated deer demonstrated high site fidelity to their release areas. In total, 75% of surviving deer returned during the fall (September–November) migration to winter range within 7km of release sites. ConclusionsOur results indicate that home range sizes and movements of translocated deer are larger than those of resident deer during the first year after release, but during the second year after release, home range sizes and movements of translocated deer are similar to those of resident deer. ImplicationsThe similar home range sizes and movements of translocated and resident deer >1 year after release, as well as the high site fidelity we observed, suggests that translocation is a strategy managers could use to establish or augment populations of mule deer on winter range.

Context Human activities can affect habitat selection by ungulates during parturition. Minimising human–wildlife conflicts during the birthing period can be critical in national and state parks that receive high numbers of human visitors. American bison (Bison bison) are an iconic species in North America, and many conservation herds of bison occupy national and state parks and wildlife refuges. Aims We investigated timing of births and birth-site selection of bison on Antelope Island State Park, Utah, at multiple spatial scales to determine the relative influence of surrounding vegetation, topography and distance to anthropogenic features (i.e. trails, roads or structures) on selection of birthing habitat. Methods We used vaginal implant transmitters to determine timing of births and to identify birth sites of bison. We used logistic regression within a model-selection framework to differentiate between birth sites and random locations, based on potential explanatory variables. We then used model-averaged coefficients to produce and project a GIS model of birthing habitat onto Antelope Island. Key results During 2010 and 2011, we quantified variables surrounding 35 birth sites and 101 random sites. Variables in top models of birth-site selection for bison included landscape curvature and elevation, averaged at a 500-m radius around birth sites, as well as distance to nearest trails, roads or structures. Five-fold cross validation (rho = 0.89; P

Context Little is known about the consequences of sexual segregation (differential use of resources by the sexes outside of the mating season) for the conservation of large mammals. Roadways (i.e. the strip of land over which a road or route passes) are ubiquitous around the world, and are a major cause of wildlife mortality, as well as habitat loss and fragmentation. Many populations of bighorn sheep (Ovis canadensis) occur at low densities and in a metapopulation structure. Roadways could affect movements of males and females differentially, an outcome that has not been considered previously. Aims We investigated the propensity of the sexes to cross a paved two-lane road and a single-lane, maintained dirt route and predicted that adult males, because of their life-history characteristics, would cross those roadways more often than females. Methods We investigated movements of male and female bighorn sheep from 1986 to 1990. We used a fixed-wing aircraft with an H-antenna on each wing strut to locate individuals each week from October 1986 to December 1990. We estimated the degree of overlap among 50% core areas of use by males and females with the utilisation distribution overlap index (UDOI). Key results We relocated male and female bighorn sheep on 948 occasions during sexual aggregation and on 1951 occasions during sexual segregation. More males than females were likely to cross both types of roadways during segregation, and the dirt route during aggregation. Propensity of males and females to cross roadways was strongly influenced by time of year (i.e. whether the period of sexual aggregation or sexual segregation). The lowest overlap in 50% core areas was between females and males during periods of segregation (UDOI = 0.1447). Conclusions More males than females crossed Kelbaker Road and the unnamed dirt route during segregation, as well as the unnamed route during aggregation. Both of those features could affect males more than females, and could result in reductions in the use of habitat or increased mortality of bighorn sheep from vehicle collisions as a result of spatial segregation of the sexes. Implications During environmental review, biologists should consider sexual segregation when assessing potential anthropogenic effects on movements of bighorn sheep. Biologists also should consider sexual segregation and how roadways, even lightly traveled routes, affect movements of male and female ungulates differently before manipulating habitat, translocating animals, or constructing or modifying roadways.

Context.Timing (mean birthdate) and synchrony (variance around that date) of births can influence survival of young and growth in ungulate populations. Some restored populations of ungulates may not adjust these life-history characteristics to environments of release sites until several years after release, which may influence success of reintroductions. Aims. We quantified timing and synchrony of births from 2005 to 2007 in four populations of reintroduced bighorn sheep(Oviscanadensis)occupyingtwoecoregions(CentralBasinandRangeandWasatchandUintaMountains)inUtah, USA,toinvestigatewhetherbighornswouldadjusttheselife-historycharacteristicstoenvironmentalconditionsofthetwo ecoregions. We also compared timing and synchrony of births for bighorns in their source herd (Antelope Island) with bighorns in an ecologically similar release site (Stansbury Mountains) during 2006 and 2007. Methods. We relocated female bighorns to record birthdates of young, and observed groups of collared bighorns to quantify use of elevation by those ungulates. We also calculated the initiation, rate and timing of peak green-up by ecoregion, using the normalised difference vegetation index. Key results.We quantified 274 birthdates, and although only separatedby 57km, bighorn populations occupying the Central Basin and Range Mountains gave birth an average of 29 days earlier than did those on the Wasatch and Uinta Mountains,which corresponded with the initiation of vegetation green-up.Additionally, bighorn sheep on the Stansbury Mountains (ecologically similar release site) gave birth at similar times as did bighorns on Antelope Island (source area). Conclusions.Populationsofbighornsheepthatwerereintroducedintoadjacentecoregionsadjustedtimingofbirthsto environments and green-up of vegetation in restoration areas. Timing and synchrony of births for reintroduced bighorn sheep in an ecologically similar release site were the same as those of their source area. Implications. Consideration should be given to the adjustment of timing and synchrony of births when reintroducing bighorns, especially when animals are released into different ecoregions. Also, biologists should select release sites that are ecologically similar to source areas, thereby reducing potential negative effects of animals adjusting timing and synchrony of births to environmental conditions of restoration areas. Additional keywords: birthing period, Ovis canadensis, parturition, restoration, translocation.