The original publication is available at http://africanzoology.journals.ac.za/pubFour lacertid lizards, Pedioplanis laticeps, P. lineo-ocellata, Meroles knoxii and Nucras tessellata,
occur sympatrically on the arid plains of the Tankwa Karoo Basin in South Africa. The aim of
this study was to evaluate the significance of foraging strategy in resource partitioning among
the four species, allowing them to co-occur in a structurally simple system with a limited
number of potential niches. Previous workers already identified P. lineo-ocellata and M. knoxii
as sit-and-wait foragers and N. tessellata as an active forager. We recorded data on three
foraging variables: movements per minute, proportion of time spent moving, and proportion
of attacks on prey whilst moving, for juveniles and adults of P. laticeps. By comparing
the foraging data obtained for P. laticeps to those for other lacertid species, we were able to
demonstrate that adult P. laticeps are ambush foragers.We also noted a significant ontogenetic
shift in foraging behaviour in P. laticeps, and, due to a significantly higher frequency of short
brief movements, we classified juveniles as mixed foragers. The sharing of an ambush foraging
strategy by at least three of the four lacertid species co-occurring on the Tankwa plains,
suggests considerable overlap along the trophic dimension of ecological space. This overlap
presumably promotes occupation of separate microhabitats by the three ambush foragers in
the Tankwa Karoo Basin.Publisher's versio