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Accelerometers can be used to monitor animal behavior remotely, but validation is required for each species. Previously, we showed that accelerometer data in collars could be used to identify specific behaviors in African elephants Loxodonta africana, using complex analytical methods. Here, we show that simple methods can also be used to identify elephant activity levels and body orientation. Subjects were 6 African elephants: 3 at Disneyís Animal KingdomÆ, Florida, USA, and 3 in Samburu-Laikipia, Kenya. Each elephant wore a collar containing a tri-axial accelerometer positioned on top of the neck. Simultaneous video recordings allowed validation of accelerometer data against observed behavior. The standard deviation of the total acceleration was shown to be a valid measure of dynamic acceleration, differentiating activity levels associated with resting, feeding, bathing, walking, and rapid walking. The mean of the total acceleration was shown to be a valid measure of static acceleration, and indicated upright and recumbent orientations. Simulations showed how accuracy was affected by sample rate, number of axes examined, and analysis window lengths. Based on 34 continuous 24 h acceleration streams, the 6 elephants exhibited an average of 2.5 h of overnight recumbence associated with minimal movement, indicating sleep. Daily activity budgets exhibited periods of minimal activity (e.g. resting, 17%), low activity (e.g. feeding, 68%), medium activity (e.g. walking, 13%), and high activity (e.g. rapid walking, 2%). Kenyan elephants were slightly more active and exhibited less restful recumbence compared to zoo elephants. Accelerometers in elephant collars can detect activity levels that are associated with specific behaviors, and can detect body orientation as a proxy for sleep. more...

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] more...

Land outside of gazetted protected areas is increasingly seen as important to the future of elephant persistence in Africa. However, other than inferential studies on crop raiding, very little is understood about how elephants Loxodonta africana use and are affected by human-occupied landscapes. This is largely a result of restrictions in technology, which made detailed assessments of elephant movement outside of protected areas challenging. Recent advances in radio telemetry have changed this, enabling researchers to establish over a 24-h period where tagged animals spend their time. We assessed the movement of 13 elephants outside of gazetted protected areas across a range of land-use types on the Laikipia plateau in north-central Kenya. The elephants monitored spent more time at night than during the day in areas under land use that presented a risk of mortality associated with human occupants. The opposite pattern was found on large-scale ranches where elephants were tolerated. Furthermore, speed of movement was found to be higher where elephants were at risk. These results demonstrate that elephants facultatively alter their behaviour to avoid risk in human-dominated landscapes. This helps them to maintain connectivity between habitat refugia in fragmented land-use mosaics, possibly alleviating some of the potential negative impacts of fragmentation. At the same time, however, it allows elephants to penetrate smallholder farmland to raid crops. The greater the amount of smallholder land within an elephant's range, the more it was utilized, with consequent implications for conflict. These findings underscore the importance of (1) land-use planning to maintain refugia; (2) incentives to prevent further habitat fragmentation; (3) the testing and application of conflict mitigation measures where fragmentation has already taken place. [ABSTRACT FROM AUTHOR] more...

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] more...

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Abstract Few data exist on the ranging behaviour of forest elephants. A feasibility study on the use of GPS telemetry as a tool to study ranging, seasonal movements and distribution was implemented in the Dzanga-Sangha and Nouabalé-Ndoki National Parks Complex of Central African Republic and Congo. The study consisted of two parts – a thorough hand-held testing of an elephant GPS telemetry collar under tropical forest conditions and the deployment of collars on two elephants. During the feasibility study the system performance was satisfactory; GPS fix acquisition success rate, VHF and UHF collar–researcher communications were adequate. Two elephants, a mature bull and an adult female, were immobilized and fitted with GPS collars in October 1998. After deployment, the female's GPS collar performed well initially, but in less than a month the GPS within the collar stopped acquiring fixes. She was subsequently located using VHF tracking. The male was never relocated strongly suggesting complete failure of the collar. Despite these setbacks, the small amount of data retrieved provide an important first insight into forest elephant ranging and daily activity patterns, with significant conservation implications. When technical difficulties of reliability are overcome, GPS telemetry will provide an exceptionally useful tool in forest elephant research and management. [ABSTRACT FROM AUTHOR] more...