Design and simulation of a bird control system for rice growers in eastern Uganda.

Abstract

Rice is an edible starchy cereal, consumed and cultivated worldwide with almost /3(a third) of the population reliant on the cereal. Uganda yields 180,000 metric tons at a local demand of 240,000 metric tons leaving a deficit of 60,000 metric tons with most of this rice being grown from the Eastern. At this deficit Ugandan farmer still encounter a reasonable loss due to post seedling damage of over 10%. Post seedling damage to rice is mainly by the weeds followed by the rice birds. Birds' damage usually occurs between the milky and early maturity stage with the birds eating more during the morning, evening and rainy hours when the grain is soft. Bird control in Uganda is mainly by local methods which include physical shouting, chasing and scaring: poisoning: static scare crows: beating sonorous sound and use of tapes that produce a whistling sound. The birds destroy the rice crop reducing its final productivity yet there is an increasing local and international demand for the crop. This has led to high and crippling crop losses coupled with significant price fluctuations to famers who have got a few options to manage these birds, hence turning bird control into an overwhelming task that has even resulted into children of school going age missing school, Yet the credited methods of bird control like poisoning and throwing stones at birds are also causing diver-stating effects on natural ecosystems and biodiversity due to their cause of reduction in numbers of birds and extinction of some bird species. Thus the main goal of this project was to design and simulate a bird control system for rice growers in eastern Uganda. From gathered literature, a floating system was deemed as the most efficient and economical. Thus a combination of a tethered balloon and a kite was designed using the law of buoyancy and the aerodynamic wind forces which were acting on the system. The design was then later simulated to visualize the motion and ensure optimal system performance thus accomplishing the second project objective. From the simulations, the designed system could float at a height due to the presence of helium gas in the balloon that provided a gross lift necessary for its floating and it was at the same time able to exploit the effect of wind on the kite and balloon that results into generating drift and lift forces capable of hovering the system with in the atmosphere so as the system would exploit on the birds’ instinctive fears of hawks. The embedded tether line was to act as the control for the system such that any motions of lift and drift by wind impact on the system should be restricted within a specific locality. The system was also supplied with an attached set of rattling devices such as beads in a tin that would produce sounds of varying intensities depending on the magnitude of the wind in order to exploit the birds' sense of sound.

To accomplish the third project goal, an economic analysis was conducted and the results showed that the system had a coverage of approximately I(one) ha giving it a benefit cost ratio of 1.986 upon its implementation. To ensure optimum system results, it is recommended that the system should be supported with good crop husbandry practices like weeding and timely planting which do help in combatting the intensities of birds attracted to the fields,