Riparian community perceptions of water hyacinth (Eichhornia crassipes) infestation and its socio-economic impacts in the Rweru-Mugesera wetland complex, Eastern Rwanda

Water hyacinth ( Eichhornia crassipes ) is one of the worst aquatic weeds in the world. Its rapid spread harms aquatic ecosystems and the people living nearby. This study was conducted around the Rweru-Mugesera wetland complex in three districts of the Eastern Province of Rwanda, namely Bugesera, Ngoma, and Rwamagana. The study used both secondary and primary data sources. Primary data were collected from a targeted sample of 399 households and 22 key informants across the three districts using structured household questionnaire surveys and an interview guide. The impacts were assessed using content analysis, descriptive statistics, Kruskal–Wallis tests, and chi-square tests. The study revealed that local communities living near areas invaded by water hyacinth had substantial knowledge of water hyacinth, which was not significantly influenced by occupation, education level, or gender. Most respondents perceived an increase in water hyacinth coverage over time, caused mainly by nutrient enrichment from agricultural runoff and increased temperatures due to climate change. Furthermore, the invasion of water hyacinth affected various socio-economic activities around the Rweru-Mugesera wetland complex. For instance, fish harvests in invaded areas dropped sharply from 2,147 to 39 kg per year, and crop yields decreased from 730 to 162 kg per season, with significant increases in fish and crop prices. Transport income also decreased from 68,705 to 30,119 Rwandan francs per year in heavily invaded areas. This study demonstrates that water hyacinth expansion has caused considerable negative effects on the socio-economic activities conducted around the wetland complex, with fishing activities being among the most severely affected. To reverse the situation, this study suggests the development of an integrated water hyacinth management strategy for the Rweru-Mugesera wetland complex that involves local riparian communities and supports their sustainable livelihoods and environmental conservation.