Socio-ecological impacts of water hyacinth (Pontederia crassipes (Mart.) Solms) on livelihoods in Katosi Ward, Uganda

Water hyacinth ( Pontederia crassipes (Mart.) Solms) is one of the most invasive aquatic plants worldwide and continues to threaten the ecological integrity and livelihoods of communities dependent on freshwater ecosystems. In Uganda, persistent infestations in the Lake Victoria Basin have disrupted fishing, water transport, trade, and access to essential services. This study assessed the socio-ecological impacts of water hyacinth on livelihoods in Katosi Ward, Mukono District, Uganda, using a mixed-methods approach. Quantitative data were collected through household surveys involving 300 respondents selected using multistage sampling, while qualitative data were obtained through focus group discussions and key informant interviews. Field ecological observations were conducted to provide contextual evidence on infestation patterns. Quantitative data were analysed using descriptive statistics, whereas qualitative data were analysed using thematic content analysis. Most respondents (71.3%) reported that water hyacinth had persisted in the area for more than ten years, and 59.3% perceived the infestation as severe. Fishing and water transport were the most affected livelihood activities, with 68.7% and 65.0% of respondents, respectively, reporting extreme impacts. Overall, 91.6% of respondents reported reduced household income, while 72.0% indicated that school-going children depended on water transport to access school, with 92.6% reporting severe disruption to school attendance during periods of peak infestation. Qualitative findings complemented the survey results by highlighting recurrent obstruction of fishing grounds and transport routes, increased household expenditure of time and financial resources on weed removal, and widespread concern regarding the effectiveness of existing management measures. The findings indicate that persistent water hyacinth infestation has substantial socio-economic implications for communities dependent on Lake Victoria. Respondents identified mechanised weed removal, strengthened environmental monitoring, enhanced institutional support, and greater community participation as priority management interventions. Integrated management approaches that combine these measures with sustainable utilisation of harvested biomass may improve both water hyacinth control and community livelihoods in the Lake Victoria Basin.