Determination of individual home range size and group composition of the main giraffe population at Entabeni Game Reserve

Large variations in giraffe home range size have been reported in previous studies, where individual home ranges usually overlap. The social structure of giraffe populations is complex and not much research has been done on their group size and group composition. To be able to identify the individual giraffe roaming the lower escarpment of Entabeni Game Reserve (EGR), Limpopo, South Africa an identification catalogue was initially created in February 2011.

A total number of 45 giraffe were individually identified in the lower escarpment of EGR. Between 9 February 2011 and 30 April 2011 there were 271 giraffe sightings, with an average number of 3.93 observations per day. The home range size of individual giraffe was determined by calculating a Mean Convex Polygon (MCP) around the data collected with a GPS. The home range of individual giraffe covered the whole lower escarpment of EGR except for the cliff areas and no difference in male and female home range size was found.

The group size ranged from 1 to 24 individuals, with small group sizes observed more frequently and 25.5% of the sightings were of a single giraffe. The group composition was mostly mixed, with males, females, and juveniles (20.5%), followed by the combination of females and juveniles/calves (16.8%), and single males (14.7%). The social structure consisted of a fission-fusion system, in which all the individual giraffe are connected, although there were some connections between certain individuals with very few intrazonal interactions, like mothers and calves. This study shows that on a small game reserve of 6200 hectares there is no difference in individual home range sizes of male and female giraffe. Their group size and composition constantly changes, but the group size is usually 1 to 5 animals. The connections between two individuals indicate the existence of social bonds.

These results should be taken into account when translocating individuals and when keeping giraffe in captivity.

Publish DateApril 23, 2021
Last UpdatedApril 23, 2021
Size0.00 KB
Download