Bottle fly trap - Kenya
Practical Action
around it and place it in hot water (3 parts boiling to 1 part cold). Remove the string; it should keep its
shape. Make a hole in the screw top by holding it over a candle, allowing the plastic to darken and
soften. Push a pencil through and enlarge the hole. Push the tube up and through this hole, leaving
the frill emerging beneath the cap. The frill should now be pinched between the bottle top and the
cap when the cap is screwed onto the bait bottle.
Other Fly Traps: The Tsetse Problem
Farmers and nomadic pastoralists in Kenya face a constant battle against a particular pest – the
tsetse fly. This tiny insect carries a disease called trypanosomosis, which can devastate whole herds
of cattle and destroy the livelihoods of farmers and pastoralists and their families.
Research carried out by the Kenya Trypanosomiasis
Research Institute, the national research
A Tsetse fly trap used in Kenya. Photo:
Practical Action / Zul.
organization mandated to research and control
tsetse and trypanosomosis in Kenya has shown that
the tsetse fly hide and breed in thickets. The
Kathekani tsetse flies are commonly found in game
parks, where they are carried by buffaloes and
elephants. The fly then moves on to cows on
neighbouring villages in Kathekani, with devastating
effects for local farmers. The research had also
shown that the tsetse fly could be tricked into
thinking that a cloth model of a cow is a real
animal. The flies are attracted by the smell from two
bottles hanging on the model, one containing
acetone and the other cow’s urine. They are
attracted to the underside of the model, in an
attempt to suck the cow’s blood. When they realise
that it is not a cow, they fly towards the light, which
is provided at the apex of the model cow being
made from mosquito netting and a polythene cage,
which are supported by a stick. There in the
polythene cage, they die from exhaustion and
exposure to UV light.
A tsetse fly trap: Photo: Practical Action /
Simon Ekless.
Pilot testing has been carried out by Practical
Action in the Kathekani area of Kenya. When it
began, with ten traps, each trap caught 2,000 flies
every day (a total of 20,000 tsetse fly). Over time and with the number of traps increased to 160,
just 22 tsetse fly catches are made a day (a total of 3,520 flies). Accordingly, the level of livestock
infection by trypanosomosis has reduced to 6% from 32% in a period of 6 years since 1998. This
shows how successful the traps have been in reducing the fly population.
References
Community-based Tsetse Fly Management: Through the Use of Trapping Technology. Practical Action
Technical Brief
Mutharia, L. (1991). Improvement of Maasai Houses in Kajiado District, Kenya. Loughborough:
University of Loughborough Water, Engineering and Development Centre.
Teaching Aids at Low Cost. (2005) Plastic Bottles in Primary Health Care. St Albans: TALC.
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