Figure 2.

RRB of A. herberti populations as a function of catchment size. Dotted lines, regressions with all 15 populations included; solid lines, regressions excluding the two largest catchment populations. (a) Response time (minutes of rainfall required to trigger RRB) as a function of catchment area. Populations inhabiting smaller catchments, where floods are rare, required longer durations of rainfall to exit the water. Error bars show s.e.m. (b) Response rate (percentage of the population that exhibits flood escape behaviour) as a function of catchment size.