Potential future economic impact of Vespula germanica (Fabricius) (Hymenoptera, Vespidae) in South Africa

The potential economic effects of the introduced German wasp, Vespula germanica (Fabricius), on fruit and vegetable industries and households in South Africa were estimated over several decades if it continues to spread. The model described was used to simulate impacts on horticulture and wine grape production and household pest control services. The results suggest that, if unmanaged, the value of damage caused by this important pest could amount to US$160–300 million over the next 50 years. This implies that the investment ceiling for a prospective eradication program is approximately US$3–6 million per year. The results were highly sensitive to the rate of spread, indicating high potential returns on investments in spread-mitigation activities if eradication is not technically feasible.