While surveys utilizing variable circular plots
may be less likely to violate distance
sampling assumptions and are easier to implement, they require a large number of
points (>2000) for uncommon species, and typically do not work as well for highly
mobile, relatively rare species (Lloyd et al. 1998). Although non-random selection of
Figure 1. The Bala portion of the Hala-Bala Wildlife Sanctuary. Part of the paved road was also
used as a transect and sections of some of the transects occur outside the sanctuary boundaries.
6