In June 2009, we used a novel technique to quantify dispersion patterns among a large group of calling male
Epomophorus wahlbergi congregated around five neighboring and synchronously fruiting sycamore fig trees (Ficus
sycomorus) in Kruger National Park, South Africa by using the physics of sound attenuation over distance to monitor and
map positions of calling males without disturbing their mating behavior. The lack of fruiting sycamore fig trees across the
area concentrated males among five fruiting trees along a 10 km stretch of riverine corridor that paralleled the river road.
We hypothesized that the patterns of dispersion among calling males would be clumped in relation to fruiting fig trees that
attract foraging females. Results show that the distribution of calling perches were clumped (R = 0.75) as opposed to
randomly or equally dispersed. In addition, we found that a 2 km section of the corridor contained the majority of calling
males and in this area calling males were more tightly clumped (R = 0.58) than across the other 6 kms of corridor. In
addition, distances among calling males and their nearest neighbor were significantly less on average (25m) in the higherdensity
area, than in the lower density areas (315m)(P < 0.001). Although most males were near fruiting figs, they
maintained a minimum dispersion and never were observed calling from the same tree. In addition, some males appeared
dominant over others and consistently positioned themselves closest to ripe fig trees where females were foraging. Our
data give previously unobserved insights into how male Wahlberg's epauletted fruit bats position their calling roosts in
relation to one another and fruiting fig trees under conditions of extreme drought and limited local food availability.