Lessons from local community perspectives on ecosystem services and disservices of invasive alien plant species in Speke Gulf, Lake Victoria, Tanzania

Abstract

Assessing the impacts of biological invasions on ecosystems particularly those driven by environmental change, including those caused by invasive plant species, is critical. However, little is known about local perspectives on invasive alien plant species, particularly in Tanzania’s lake zones. This study examined community perceptions of ecosystem services (ES) and ecosystem disservices (EDS) associated with five invasive alien plant species: Eichhornia crassipes, Lantana camara, Chromolaena odorata, Argemone mexicana, and Ipomoea hildebrandtii and the management options used by communities across four villages in the Mara and Simiyu regions. Data were collected through household surveys (n = 120), focus group discussions (n = 3), and key informant interviews (n = 11). Quantitative data were analysed using descriptive statistics and binomial logistic regression, while qualitative data were analysed thematically. Overall, respondents reported ecosystem disservices more frequently than services. While some benefits were identified, including livestock fodder, medicinal use, and fuel, negative impacts dominated local perceptions. The most commonly reported disservices included increased management costs, reduced plant diversity, or disrupted biodiversity loss. Logistic regression results showed that education level and village location significantly influenced perceptions of both ES and EDS, whereas age and gender did not. Among the species studied, E. crassipes was perceived as the most difficult and costly to manage, and control efforts for both E. crassipes and L. camara were widely considered ineffective. These findings highlight the importance of incorporating local knowledge and socio-demographic factors into invasive species management. Context-specific, community-based, and species-specific strategies are needed to improve the effectiveness and sustainability of invasive alien plant species management in the Lake Victoria basin.