Analysis Of Glossina Swynnertoni

Glossina swynnertoni is a tsetse species with extremely limited geographical distribution. It occupies a very small part of East Africa covering northern Tanzania (Arusha and Manyara regions and parts of Shinyanga and Mara regions) and the adjoining Maasai Mara in southwestern Kenya [1-3]. In its area of distribution it inhabits dry woodlands of savannah at an attitude range of 900 – 1800 metres above sea level [4, 5] and has preference for more open vegetation types provided that some small thickets and natural hosts are available [1].
Glossina swynnertoni is one of the most abundant tsetse fly species in its area of distribution in Southwestern Kenya and Northern Tanzania [2, 6], playing an important role as vector of human trypanosomosis
Live bait (involving use of animals) is the cheapest method of tsetse control especially when restricted application of insecticide is adopted [22, 26, 27]. In this case insecticide is sprayed on the legs and belly of larger/older cattle in the herd thus minimizing environmental contamination and cost of insecticide. Taking in mind that restricted or conserved areas are the main habitats [2, 28], such method is not suited for use in long run. This is because conserved areas such as national parks and game reserves are legally cattle-free. Therefore, artificial bait technology become potentially the most feasible and cost effective method of tsetse control. This technology is based on exploitation of host seeking behavior of tsetse flies [29]. It combines visually attractive killing device such as mechanical trap or an insecticide-impregnated cloth target, with olfactory attractants that mimic a natural host [30, 31]. The traps are useful for sampling of tsetse population in a particular area. This is because they provide room for identifying and counting the species caught. On the other hand, the targets expose the flies to the lethal dose of insecticide through contact with insecticide-treated surface and are knockdown, though they might fly away but later die through starvation or predation. This review explores the role of artificial bait technology for control of east African tsetse species
Studies have shown that feeding interval of G. swynnertoni is even shorter (2½ - 3 days) and hence described as being adapted to feeding more frequently [91, 93, 94]. With regard to this behavior, G. swynnertoni can even be suggestively more vulnerable to traps or targets. In addition, whether the flies are hungry or not, they have a tendency to display a phenomenon known as circadium rhythm of activity (flight activity) which is the tendency to explore large objects and settle on them [40, 41]. Being the case, G. swynnertoni has a unique flight activity pattern which is not described in other tsetse flies [42]; it has been observed to be active throughout the day [43]. The flight activity was further characterized by Ndengwa in 2001 as unimodal whereas males were found to be at peak activity at 1100 – 1200 hrs and females at 1400 – 1600hrs. And both sexes remained active in the afternoon and activity decline rapidly towards dusk (1700 – 1800hrs) [1]. During this time its movement is more influenced by a moving object [16, 32, 40, 44]. Observation by Moggridge in 1936 indicated that G. swynnertoni can be attracted by a moving object in an open area up to a distance of 90 - 275 m [45]. Therefore, these characteristic factors aid the daily dispersal rate and hence, increase the probability that tsetse flies such as G. swynnertoni will encounter traps or targets [16,