Review of blackfly (Diptera : Simuliidae) control in South Africa

Abstract

The medical, veterinary and economic importance of blackflies in South Africa, and the historical development of blackfly control programmes in various South African rivers, are reviewed in this paper. In 1996 it was estimated that blackflies can cause more than R 88 million damages per annum along the middle and lower Orange River where Simulium chutteri is considered the main pest species. A clear link between the construction of dams and the spread of the blackfly problem was shown. Four phases characterize the development of blackfly control in South Africa: (1) during the 1960s blackflies in the Vaal River were controlled with DDT; (2), during the 1970s and into the 1980s blackflies were controlled using water-flow manipulation; (3) when used at strategic times, water-flow manipulation could be used to enhance the effect of natural predator populations; and (4) during the 1990s the organophosphate temephos and toxins produced by the bacterium Bacillus thuringiensis var. israelensis were tested for their efficacy against blackflies. The larvicides temephos and B. thuringiensis proved to be effective and are still used in several control programmes. The latest research focuses on the factors that influence adult blackfly survival and annoyance, as well as the development of methods that can be used to protect sheep from blackfly attacks.

Notes on distribution of Simulium damnosum s. l. along Atbara River in Galabat sub-focus, eastern Sudan

“…Construction of dams has adverse effects on the physical and biological environment [5, 9, 25]. In this study, aquatic stages of Simulium black flies were collected from 40 breeding sites during 2009 and 2013.…”

Discovering Resilient Pathways for South African Water Management: Two Frameworks for a Vision

“…Water management in South Africa: a timeline of events. Sources: Herold et al 1992, Chutter et al 1996, World Commission on Dams 2000, World Resources Institute (WRI) 2000, Thompson et al 2001, Turton and Meissner 2003, DWAF 2003, Metsi Consultants 2002, Myburgh and Nevill 2003 The MA also defined five constituents of human well-being: basic material for a good life, health, good social relations, security, and freedom of choice and action (MA 2005). Human well-being is influenced by both ecosystem services and drivers of change, and may have feedbacks on indirect drivers, such as when health problems burden a national economy.…”

“…Over time, the ecological change that results from this infrastructure development undermines some of the benefits that this infrastructure was originally intended to secure. For example, the building of the Orange River Development Project in the 1960s improves water availability for the commercial farming sector, but alters river flows so drastically that a prolific pest blackfly (Simulium chutteri) invades a large section of river used by livestock farmers, and requires significant ongoing investment in mitigation (Myburgh and Nevill 2003). During this time, increasing demand for timber drives the commercial planting of non-native tree species in mountain catchments, reducing streamflow (Görgens and van Wilgen 2004) and facilitates the spread of non-commercial invasive alien plant species (Le Maitre et al 2004).…”

Future Ecosystem Services in a Southern African River Basin: a Scenario Planning Approach to Uncertainty

“…Group members cited numerous cases of ecological surprise. For example, massive dams built in the 1960s and 1970s to stabilize the Gariep River's flow regime enabled a blackfly ( Simulium chutteri ) to proliferate and affect livestock operations along the river, imposing severe costs on the precise industry the dams were supposed to benefit (Myburgh & Nevill 2003).…”