Reunion in wild cheetah: How do separated companions meet again?
Hubel1, T.Y., Shotton, J., Wilshin, S.D., Horgan, J., Klein, R., McKenna, R., Wilson, A.M. (2016) Cheetah reunion - the challenge of finding your friends again. PLoS ONE 11(12)
This study investigated separation and reunion behaviour in cheetahs by tracking the movements of three bonded individuals in the Botswanan Ghanzi farmland area over six months. The purpose of the research was to investigate possible strategies utilised by this species to facilitate reunion with known conspecifics after a period of protracted separation, and understand challenges in effecting such a reunion in an extensive home range.
The movements of three male cheetahs, believed to be siblings, were recorded using global positioning system (GPS) data, transmitted via neck collars. The cheetahs remained together for the duration of the observations, with the exception of a 31-day period when one individual separated from the others, after which they reunited. The size of the cheetahs’ home range was estimated to be 819km2, 637km2 of which were utilised during the separation period. Based on the authors’ proposal of a recognition distance of 300m (at which the animals were expected to be able to identify each other), the probability of a random encounter of this proximity during the separation period was calculated as 1.06%.
Was a cheetah reunion likely?
The lone cheetah was recorded as being within 770m of the others on one occasion and 1110m on another, and the tracks of the two groups crossed on 31 occasions without resulting in reunion. The cheetahs were not observed to directly follow others’ tracks; however, the reunion was immediately preceded by the lone cheetah moving in a looping pattern after encountering tracks left by the other group within 2.4 hours prior. A similar looping pattern was recorded on one previous occasion of track crossing, but five days had elapsed since the previous group had passed. The reunion did not occur in the vicinity of the place of initial separation, nor in an area frequently visited by any of the cheetahs either before or after the reunion (during the observation period), suggesting no particular significance of the site.
Whilst the reasons for separation and reunion in cheetahs are not fully understood, and this was a small study of only three subjects, the findings indicated that free-ranging cheetahs do not appear to track conspecifics using scent alone, as evidenced by the lack of linear tracking; nor use extensive vocalisation to contact conspecifics, as evidenced by the failure to identify others at distances of 770m or 1110m. The cheetah in this study appeared to respond to recent scents by utilising a looping search pattern to facilitate the detection of others, following coincidental but timely encounter of conspecifics’ tracks.
World Animal Protection’s view
As the first to yield such detailed positional data on a coalition of free-ranging cheetah, this study provides valuable insight into both ranging and social behaviour of the species. More research is necessary to fully understand the welfare significance of separation and reunion behaviour in cheetahs, and, associated with this, the impact that any events likely to disturb these natural behaviours may potentially incur.