Data from: Exploring movement decisions: can Bayesian movement-state models explain crop consumption behaviour in elephants (Loxodonta africana)?
Vogel, Susanne et al. (2020), Data from: Exploring movement decisions: can Bayesian movement-state models explain crop consumption behaviour in elephants (Loxodonta africana)?, Dryad, Dataset, https://doi.org/10.5061/dryad.dr7sqv9v9
1. Animal movements towards goals or targets are based upon either maximization of resources or risk avoidance, and the way animals move can reveal information about their motivation for movement. 2. We use Bayesian movement models and hourly GPS-fixes to distinguish animal movements into movement states and analyse the influence of environmental variables on being in and switching to a state. Specifically, we apply our models to understand elephant movement decisions surrounding agricultural fields and crop consumption. As it is unclear what the role of habitat features are on this complex issue, we analyse whether elephants target agricultural crops for consumption, or simply pass through them in search of water. 3. Our Hidden-Markov models divide elephant movements into two states: exploratory movements that are fast and directional, and encamped movements that are slow and meandering. For each elephant, we ran 16 models with each possible combination of habitat features (river, elephant corridor, agricultural field, trees), and repeated these analyses including interaction effects with both season and time of day. We used cross-validation to select the best performing model, and GLMMs to analyse the influence of habitat features on being in and switching to a state. 4. Our results show that in corridors, exploratory movements are dominant. Elephants mainly showed encamped movements at the river during the dry season, when temporary water sources have dried out and elephants rely on this permanent water source. In fields, males most often exhibited exploratory movements to and from the river, while females showed an increase in the frequency of encamped movements at night –when most crop consumption and movements through fields occur- and during the dry season. 5. The predation-risk hypothesis could explain this behaviour, since foraging in fields might be less risky under the cover of darkness and during the dry season when farmers are absent from fields. This sexual segregation in elephant movement decisions highlights the importance of risk in movement patterns, while the increase in encamped movements in the dry season suggests the importance of agricultural timing. Taking this into account could increase efficiency of elephant crop consumption mitigation. 08-Jan-2020
Natural Environment Research Council, Award: DTP Student award Susanne Marieke Vogel
Pembroke College, University of Oxford, Award: DTP Student award Susanne Marieke Vogel
Dr. Hendrik Muller’s Vaderlandsch Fonds, Award: Student award Susanne Marieke Vogel