Lake Tanganyika is an important ecosystem in eastern Africa, which historically has supported one of the world’s most productive freshwater fisheries. However, stocks of important commercial fish have decreased significantly. Scientific evidence suggests that fisheries are partly threatened by climate driven reductions in lake productivity. This project will provide a better understanding of how sensitive Lake Tanganyika is climate change and evaluate future sustainable fisheries. Based on active engagement with local scientists, students, fishermen and lake managers, the project will build capacity on contemporary lake monitoring to provide a fundamental understanding of how environmental conditions relate to fish yields and improve decision-making capacity for fishermen. The gathered data will be used as a platform to inform Tanzanians about their unique lake via local workshops targeted to local poor fishermen, and to lake managers and larger scale fishermen via seminars and through a new lake website. The data will also be used to develop the first full scale biogeochemical model of Lake Tanganyika, and be used to verify a decadal time series of satellite based observations of water temperature, algal biomass and primary production. Coupling this information with knowledge on fish species traits will allow us to investigate how abundance of important pelagic and littoral fish responds to temperature-mediated changes and compare this with effects of intensified fisheries.
Midterm report 2017:
Since 2015 monthly sampling of water quality data has been done along with training of TAFIRI staff and Ph.D. students in the use of field and laboratory equipment. Operating procedures has been documentation. In 2016, a monitoring buoy was developed and installed, providing data for modelling of lake productivity. Historical and new data on water quality, fish landings, and fish growth have also been gathered and digitized, providing essential data to setup models of lake functioning and fish productivity. These models are being used to provide predictions about how the lake ecosystem will change under future climate scenarios. The importance of fishing equipment and practices were investigated, and a series of interviews with local fishermen and stakeholders has been conducted. This has provided a deep understanding of conditions affecting fisheries including the local conception of challenges with fisheries. The 3 Ph.D. students have participated in several conferences, and each submitted a research paper with several more in the pipeline.