1. Averaging the values for whitehanded gibbons in Figure 12.5, a male who can search an area 100 m either side of his route of travel with a mean day journey of 1.463 km and a total range area of 0.453 km2 would be able to search 64.6% of his territory each day. With a probability of locating his female of α= 0 646 his mean return time (i.e. the interval between successive encounters with the female) when searching randomly is 1/α = 1.55 days.