Movement- and attack-based indices of foraging mode and ambush foraging insome gekkonid and agamine lizards from southern Africa

Two lizard foraging modes, ambush and active foraging, are usually quantifi ed by the variables MPM (movements per minute) and PTM (proportion of time spent moving), but both variables may be affected by behaviors other than f oraging. We introduce PAM, the proportion of attacks on prey discovered whi le lizards are moving (in relation to total attacks). PAM focuses exclusive ly on foraging behavior Preliminary data reveal a very high, significant ra nk correlation between PAM and PTM, and a fairly high, but nonsignificant c orrelation between PAM and MPM. Collection of PAM data can be very time-con suming. In the absence of PAM, PTM appears to be a superior index of foragi ng activity to MPM, but all three indices provide valuable information on d ifferent aspects of foraging. We additionally present data for four agamine and five gekkonid species from southern Africa. The first quantitative dat a for agamines (all for Agama) agree with previous qualitative assessments that members of several agamine genera are ambush foragers. All the gekkoni ds, including three species of Rhotropus and one each of Pachydactylus and Phyllodactylus, are ambush foragers, like most geckos studied to date.