CONSERVATION IMPLICATIONS OF LONG-TERM POPULATION TRENDS, ENVIRONMENTAL CORRELATES AND PREDICTIVE MODELS FOR NAMAQUA SANDGROUSE PTEROCLES NAMAQUA

Hunting bag data for Namaqua sandgrouse Pterocles namaqua from an esta te near Kimberley, South Africa, for the period 1907-1992 were analyse d to investigate population trends, environmental correlates and to de velop predictive models for population fluctuations An apparent popula tion decline between 1950 and 1992 may be an artifact of increased san dgrouse dispersion in response to an increased number of artificial wa tering points on the estate, and in the surrounding area, during this latter period. Peaks in sandgrouse abundance are significantly negativ ely correlated with December rainfall and significantly positively cor related with March rainfall. Furthermore, annual sandgrouse abundance and March rainfall showed similar peaks at four-year cycles during 190 9-1939. Therefore, a rainfall 'score' which takes cognizance of both D ecember and March rainfall is useful for predicting annual sandgrouse abundance before the forthcoming hunting season. However, correct pred ictions of low sandgrouse abundance were more common than correct pred ictions of high sandgrouse abundance. These environmental correlates a nd predictive models are useful for forecasting the annual viability o f commercial hunting of these populations.