2.2.2 Bushpig relative abundance using the transects
Bushpigs are crepuscular and nocturnal and seldom observed. Therefore the only realistic method of assessing bushpig abundance is the use of indirect evidence provided by tracks, as well as photographs obtained by static camera traps. Bushpig track transect counts, using the eight transects used for warthogs, were conducted on a separate occasion (June 2018 to December 2018). In order to maximise statistical reliability, each transect was walked 21 times recording bushpig tracks encountered. The researcher was assisted by game scouts with experience in animal tracking. Bushpigs tracks, when compared to those of warthog, have broader hoofs and their claw mark show clearly on the tracks. To avoid the risk of double-counting, tracks were erased using branches. For each observation the following data were entered in MS Excel : date, repetition, transect number, vegetation type, length of that particular vegetation type in a transect, GPS coordinates of where the observation was made, number of tracks and, number of events (an event is a discrete cluster of tracks on a particular transect). Tracks indicated the total count of tracks recorded per event. A linear mixed-effects regression model was performed to predict the mean number of events and tracks based upon habitat (Pinheiro & Bates, 2006), allowing an assessment of relative bushpig abundance indicators (tracks an events) in each of the four habitat categories in NGR.