Water hyacinth: an environmental disaster in the Winam Gulf of Lake Victoria and its control
MetadataShow full item record
Water hyacinth has in the recent past had an adverse socio-economic impact on the lakeshore communities of Lake Victoria, particularly in the Winam Gulf. Fishing, lake transport and water supply have been seriously affected by the water hyacinth. KARI’s efforts at mitigating this disaster have so far been in the form of a twopronged management strategy consisting of physical and biological measures. The local administration has been involved in mobilizing the local communities to remove water hyacinth manually at strategic sites. However, there have been a number of constraints, mainly community attitudes to self-help activities. The Kenya Industrial Research and Development Institute (KIRDI) has developed a prototype mechanical harvester in a KARI-funded local initiative. The prototype has been tested and is still being improved; again with varying attitudes on the part of financiers. KARI’s biological control efforts, though not a popular option amongst to the communities, has had an impact at the Police Pier. At the Pier, the critical threshold of 5 Neochetina weevils per plant has been reached, with plants stunted and incapable of reproduction. Field stations near the lakeshores will be part of a community-based rearing programme. Isolates of the fungal pathogens Cercospora spp. and Alternaria spp. are currently undergoing glasshouse and host-specificity tests. Chemical control using herbicides is seriously being considered at a regional level. Lake Victoria waters are used for domestic purposes and by livestock. Local communities may be required to avoid treated areas. Only surgical or partial sprays with environmentally safe herbicides may be possible.
- Conference Papers