Accepted Manuscripts / The effect of capture on ranging behaviour and ...
The effect of capture on ranging behaviour and activity of the European roe deer Capreolus capreolus
Nicholas Morellet, Hélène Verheyden, Jean-Marc Angibaut, Bruno Cargnelutti, Bruno Lourtet & Mark A. J. Hewison
Locating and monitoring animals using tracking devices is a method commonly used for many taxa to study characteristics such as home range size, habitat selection, movement patterns and other aspects of ranging behaviour. Fitting such devices requires the capture and handling of the study organism and researchers must then assume that a monitored animal behaves in a “normal” way. We investigated whether the capture and handling of roe deer Capreolus capreolus induces behavioural alterations. In particular, we expected that the roe deer would express a “seeking a refuge and waiting before returning” strategy immediately after release, taking shelter far from the capture scene, in closed habitat, and exhibiting a reduced activity level. We evaluated the effect of capture and handling on 112 roe deer equipped with GPS collars, considering a period of 50 days after release. We compared the first ten days after release with the subsequent days for the following behavioural parameters: the distance to the barycentre of their GPS fixes, presence in forest habitat, distance to the nearest forest patch, distance to a source of human disturbance and activity level. We found pronounced differences in terms of spatial behaviour, habitat use and overall activity level between these two periods in GPS monitored roe deer. We also found differences in terms of spatial displacement between the sexes, with females responding less than males, and among age classes, with yearlings responding the most and fawns the least, to the capture and handling event. Finally, spatial displacement of roe deer increased with openness of the habitat due, in part, to the scarcity of available shelter in open areas. We conclude that the roe deer expressed a strategy consisting of seeking a refuge and waiting before returning after capture, handling and fitting of a collar, with displacement towards a refuge habitat, in or near woodland, avoidance of sources of human disturbance and reduced activity levels. From a practical point of view, we recommend removing data during the first days of monitoring when behavioural alterations due to capture and handling may be pronounced.
Key words: capture and handling effects, disturbance, home range, shelter, space use, stress, telemetry