Data from: Exploring movement decisions: can Bayesian movement-state models explain crop consumption behaviour in elephants (Loxodonta africana)?

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