Controlling tsetse with targets

What's the best target for controlling tsetse?

Targets come in various shapes and colours. Which is the best?

Target colour

In general tsetse are attracted from a distance by blue and black colours, with blue being slightly more attractive than black (see references by Green). However, tsetse will land on a black surface in preference to a blue one and they also land on horizontal oblongs in preference to vertical ones. These basic responses provide the principles that underly the design of targets in common use.

When blue and black targets are used, the insecticide is applied to the black portion only, where most of the tsetse will land. This selective application allows the amount of insecticide required to be reduced.

Types of target that have been used to control various species of tsetse are shown below.

All black	Suitable for all species
All blue	Riverine species,G. austeni
Blue-black vertical panels	G. morsitans, G. pallidipes
Blue-black Horizontal panels	G. morsitans
Black-blue-black, vertical panels	G. palpalis, G. brevipaplis, G. austeni
Blue-black-blue, vertical panels	G. morsitans, G. pallidipes

Target Shape

Larger targets are more effective than small ones (Hargrove, 1980), but larger targets are also more expensive. In general, consider having a target of about 1 - 1.5 square metres, with the length being 100-170% of height (Vale, 1993). Examine the widths of cloth available in the market and adjust the dimensions to allow minimal cutting and wastage of cloth.

Target support

You can use either steel or wooden poles to support the target. Wooden poles are cheaper but less durable.

Tsetse Plan will help you choose a target that suits your local situation.

References
Green, C.H. (1986) Effects of colours and synthetic odours on the attraction of Glossina pallidipes and G. morsitans morsitans to traps and screens. Physiological Entomology, 11, 411-421.

Green, C.H. (1988) The effect of colour in trap- and screen-orientated responses in Glossina palpalis palpalis (Robineau-Desvoidy)(Diptera: Glossinidae). Bulletin of Entomological Research, 78, 591-604.

Green, C.H. (1989) The use of two-coloured screens for catching Glossina palpalis palpalis (Robineau-Desvoidy)(Diptera: Glossinidae). Bulletin of Entomological Research, 79, 81-93.

Green, C.H. (1990) The effect of colour on the numbers, age and nutritional status of Glossina tachinoides (Diptera: Glossinidae) attracted to targets. Physiological Entomology, 15, 317-329.

Green, C.H. (1994) Baits methods for tsetse fly control. Advances in Parasitology, 34, 229-291.

Green, C.H. & Cosens, D. (1983) Spectral responses of the tsetse fly Glossina morsitans morsitans. Journal of Insect Physiology, 29, 795-800.

Green, C.H. & Flint, S. (1986) An analysis of colour effects in the performance of the F2 trap against Glossina pallidipes Austen and G. morsitans morsitans Westwood (Diptera: Glossinidae). Bulletin of Entomological Research, 76, 409-418.

Hargrove, J.W. (1980) The effect of model size and ox odour on the alighting responses of Glossina morsitans Westwood and G. pallidipes Austen (Diptera: Glossinidae). Bulletin of Entomological Research 70, 229-234.

Vale, G.A. (1993) Development of baits for tsetse flies (Diptera: Glossinidae) in Zimbabwe. Journal of Medical Entomology 30, 831-842.