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Monitoring anthropogenic impacts on wildlife can be challenging, particularly when human activities affecting wildlife are cryptic. Using anti-predator behaviors as proxies for perceived pressure is appealing because of the relative ease with which they can be recorded and the presumed relationship between the threat of interest and a predator stimulus. However, behaviors are plastic and affected by factors unrelated to human activity. Consequently, it is critical to assess the relationship between behavioral indicators and their context before interpretation. In this study we used a combination of behavior, movement and demography from a threatened population of African elephants in northern Kenya to determine whether reaction to research vehicles was indicative of poaching pressure. We used mixed-effects models predicting reaction of elephants to observer vehicle approaches in which we treated individuals as random effects and included ecological, anthropogenic, spatial, social and demographic predictor variables. Contrary to our hypothesis, recorded levels of reactive behavior did not increase with poaching levels in either a population-level dataset or a data subset of individuals whose spatial behavior was precisely known via radio-tracking. Rather, primary productivity positively predicted reactive behavior in both datasets. This relationship was heightened by the presence of musth males in the radio-collar dataset. Reactivity was not related to the time since entering the protected areas, but increased among groups that spent less time in the protected areas. Inter-individual differences were apparent, suggesting the importance of inherent differences (e.g. personality) across groups. In our study, elephants plagued by a severe human threat did not react defensively to humans in another context, suggesting nuanced discrimination of threats. Our study demonstrates the caution that should be taken in designing studies that use behavioral indices to represent threat and contributes to a growing body of literature employing behavioral indicators to monitor wildlife populations of conservation concern. [ABSTRACT FROM AUTHOR]

Resident white-bearded wildebeest (Connochaetes taurinus) have experienced widespread population declines across much of their range over the past few decades, the drivers of which are attributed to landscape changes. Despite the ecological significance of this decline, surprisingly little is known about the resource needs and habitat use of these animals. Using global positioning system data collected from 2010 to 2013, we assessed resource selection of wildebeest inhabiting three study areas in Kenya with varying degrees of natural and anthropogenic disturbance to identify potential behavioral mechanisms underlying potential landscape-driven declines. Wildebeest were observed to consistently avoid anthropogenic features and dense woody cover, irrespective of season, suggestive of avoidance of landscape features that would likely be associated with increased predation risk. Wildebeest also avoided primary roads, particularly across the Athi-Kaputiei Plains where human density and landscape alteration was greatest. The strongest response to normalized difference vegetation index was observed across the Amboseli Basin, the least productive and anthropogenically altered of our three study areas, leading to pronounced seasonal shifts in space use. Selection of natural and anthropogenic features was similar across the Mara and Athi-Kaputiei Plains, with the exception of the response to roads which likely relates to differences in road use. We also observed strong shifts in space use between day and night periods, particularly in relation to anthropogenic features and likely related to human circadian activity patterns. The observed variability in selection provides detailed information to how wildebeest react to local environmental factors across landscapes, and provides insight to how landscape fragmentation amplifies habitat loss for wildebeest by driving spatial avoidance, a likely mechanism contributing to population declines in this species. The quantified responses of wildebeest to landscape features can aid future conservation management efforts and planning to sustain imperiled wildebeest populations. [ABSTRACT FROM AUTHOR]

Two hundred years of elephant hunting for ivory, peaking in 1970–1980s, caused local extirpations and massive population declines across Africa. The resulting genetic impacts on surviving populations have not been studied, despite the importance of understanding the evolutionary repercussions of such human-mediated events on this keystone species. Using Bayesian coalescent-based genetic methods to evaluate time-specific changes in effective population size, we analysed genetic variation in 20 highly polymorphic microsatellite loci from 400 elephants inhabiting the greater Samburu-Laikipia region of northern Kenya. This area experienced a decline of between 80% and 90% in the last few decades when ivory harvesting was rampant. The most significant change in effective population size, however, occurred approximately 2500 years ago during a mid–Holocene period of climatic drying in tropical Africa. Contrary to expectations, detailed analyses of four contemporary age-based cohorts showed that the peak poaching epidemic in the 1970s caused detectable temporary genetic impacts, with genetic diversity rebounding as juveniles surviving the poaching era became reproductively mature. This study demonstrates the importance of climatic history in shaping the distribution and genetic history of a keystone species and highlights the utility of coalescent-based demographic approaches in unravelling ancestral demographic events despite a lack of ancient samples. Unique insights into the genetic signature of mid-Holocene climatic change in Africa and effects of recent poaching pressure on elephants are discussed. [ABSTRACT FROM AUTHOR]

Individual based demographic records of the elephants utilizing Samburu and Buffalo Springs National Reserves were collected from 1998 through 2003 and indicate that this elephant population was increasing at an average rate of 4.6% per year. Although the majority of carcasses were not found, known sources of mortality include disease, injury, and predation by lions and humans. Poaching did occur during the study period, however the population is increasing and thus our findings indicate ivory poaching has limited impact on the demographic status of these elephants. This population is part of the Samburu/Laikipia MIKE Site and thus its status is relevant to CITES ligislation. [ABSTRACT FROM AUTHOR]