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Studying the spatio-temporal distribution of flies within an agroecosystem can provide improved management recommendations for monitoring efforts and reduce management costs (Papadopoulos et al., 2003). It has been further observed that hotspots of C. capitata in Italy can be related to not only the type of host fruit, but also to the stage of development (maturation) and fruit availability on the tree and on the ground (Sciaretta & Trematerra, 2011). If an annual pattern in distribution of certain pest species can be quantified, farmers would greatly benefit from such data as management practices, such as labour-intensive sanitation measures, can then be fine-tuned and ultimately result in the lower input of pesticides into agro-ecosystems. An important requirement for management techniques of C. capitata and C. rosa is to determine the composition of these two species in terms of adult population and fruit infestation, in different fruit growing areas of the Western Cape (Manrakhan & Addison, 2007). This has been quantified to some extent in commercial orchards and non-commercial hosts in the Western Cape (De Villiers et al., 2013), but due to the variety of different non-commercial hosts that have not been sampled, it is important to gather more information for host utilization by fruit flies in home gardens. The aim of this chapter is therefore to establish the population dynamics of C. capitata and C. rosa in home gardens associated with commercial areas in order to quantify the role of alternate hosts more clearly in Western Cape fruit production areas. To further improve monitoring efforts, the influence of different lures was assessed for the monitoring of these two fruit fly species.
Materials and methods
Five non-commercial sites (home gardens) in the Western Cape Province were selected for sampling, based on their close proximity to areas of commercially-grown deciduous fruits (Fig. 2.1). The five sites were located in Stellenbosch, Elgin, Villiersdorp and Worcester: The
