Making use of the spatial-temporal capabilities of EwE in small-scale, tropical fisheries settings
Tuesday 5 September 2023, 18:00 CEST (Brussels, Amsterdam, Madrid)
Ecosystem models, such as Ecopath with Ecosim (EwE), integrate ecological processes, environmental dynamics, and human activities, making them valuable tools for developing ecosystem-based management strategies. With its new Habitat Foraging Capacity module (E-HFC), EwE can even offer a full spatial and temporal resolution of marine ecosystem dynamics. This makes EwE a powerful tool for the exploration of management strategies in tropical, small-scale fisheries allowing for the evaluation of socio-economic trade-offs. However, time-series data and a clear understanding of what drives the distribution of organisms in the system are prerequisites for using EwE reliably. This information is usually missing for tropical, small-scale fisheries hampering the use of EwE for the exploration of management strategies.
A model case study is Chwaka Bay – a tropical bay system in East Africa (Zanzibar), where local communities heavily rely on fisheries resources, and concerns about overfishing have led to a need for more sustainable fisheries management. We used a recently developed Chwaka Bay Ecopath model to examine various gear and spatial management strategies. Faced with the lack of time-series data on biological and environmental variables, we explored different approaches for parameterizing the spatial-temporal capabilities of EwE and examined the use of local ecological knowledge to assess model outputs.
Jennifer Rehren is a researcher at the Thünen Institute for Sea Fisheries in Germany. Her research focuses on the sustainable utilization of marine ecosystems. Much of her work has been on the assessment of data-poor, coastal fisheries systems by applying different quantitative methods ranging from stock assessment, and spatiotemporal models to ecosystem models.