Effects of a predator control experiment on Grey-winged Francolin (Scleroptila africanus) populations

Abstract

One of the key findings of the Grey-winged Francolin Research Project conducted on the Stormberg Plateau, Eastern Cape Province, South Africa during 1988–1992 was that predation, particularly by small mammals on incubating female Greywinged Francolin Scleroptila africanus and their nests, was a major cause of mortality. To assess the response to this predation, small mammal predators were trapped intensively during the francolin breeding season in two 500ha plots, one on the farm Buffels Fontein and one on the farm Boschoff's Kraal. Trapping was not simultaneous on the two plots, but rather during 1992–1994 on Buffels Fontein and during 1995 and 1996 on Boschoff's Kraal. The Yellow Mongoose Cynictis penicillata was the most commonly trapped predator species (83%) in both plots. Grey-winged Francolin numbers during trapping in the plot at Buffels Fontein declined less during a drought than those in the untrapped control plot at Boschoff's Kraal. This suggests that the control of predators may buffer the negative effects of drought on Grey-winged Francolin reproductive success. However, the increases of populations in both plots during a period of higher-than-average rainfall indicate that Grey-winged Francolin can withstand predation during normal rainfall years.