About Pet Sins Webzine
Skip navigation and go to main content
Pet Sins November 2006

James Ogwang, Biocontrol Entomologist - a weevil solution for Lake Victoria's water hyacinth infestation

As head of Biological Control Programs for Ugandan National Agriculture Research Organization's Namulonge Agriculture and Animal Production Research Institute's (NAARI), Dr James Ogwang is an example of local people coming up with appropriate solutions for local problems. Water hyacinth from South America had invaded Lake Victoria by the 1980s. Without natural enemies in its new home, the weed spread to clog much of Lake Victoria's Uganda shoreline, markedly reducing the quality of drinking water and fish populations. The weeds also threatened public health by providing a new habitat for water snails harboring the deadly schistosomiasis parasite.

Dr Ogwang decided to source the weed's native home for its natural enemies. He imported a South American weevil which fed on the water hyacinth. He first tested the weevils to make sure they did not have a taste for native crops, thus avoiding the pitfalls of biocontrol programs in other countries which failed to take into account the impact a non-native biocontrol agent would have on the local environment. The biocontrol program was a success - the weevils ate and depleted the water hyacinth, unclogging Uganda's major waterways in the 1990s. NAARI's biocontrol unit is still pushing forward research on local pathogens which can form part of a multifaceted approach in combating the hyacinth problem.1

Dr Ogwang's influence has extended beyond Uganda and indeed beyond Africa. He has trained officials in Rwanda and Burundi on the management of the water hyacinth infestation.2 On the global level, Dr Ogwang is considered a key role player in water hyacinth biological control.3

Dr Ogwang's work has been featured in National Geographic's Strange Days on Planet Earth: Lake Victoria's Water Hyacinth Problem. It appears the idea of using biocontrol agents is something that outsiders have to bring to Africa - in his boyhood, Ogwang had seen village folk use biocontrol insect agents to control pests.


Notes:

New Vision Online - Hyacinth mite developed

Biological Control of Water Hyacinth in the Kagera River Headwaters of Rwanda: A Review Through 2001

Minutes of the Second General Meeting of the IOBC Working Group on the Biological and Integrated Control of Water Hyacinth