Nsumbu Tanganyika (Zambia) — Impoverished communities living along the shores of Lake Tanganyika (sub-Saharan eastern Africa) depend on fish for high-protein sustenance and cash income. Climate change, destructive fishing practices, and siltation (sediment pollution of nearshore spawning grounds from slash and burn deforestation) pose severe threats to Lake Tanganyika’s fisheries. These pressures have been accelerating over the past several decades, driven by explosive population growth and refugee influx to the region.
Collapse of Lake Tanganyika’s fisheries represents a looming humanitarian and ecological disaster that is widely acknowledged. However, few harmonized efforts have been undertaken to protect food security and safeguard the health and wellness of poor people that rely on fish for their nutrition.
One of the most successful conservation strategies designed to protect fish resources is the development of small-scale coastal protected zones that are administered by local stakeholders. This mode of community-based fisheries management requires detailed knowledge of near shore benthic habitats, in order to strategically focus conservation efforts to those areas vital to fish breeding and rearing. Regrettably, this information is unavailable for most of Lake Tanganyika.
The project’s team proposes to use high-resolution geophysics and limnogeological sampling (sediment cores and dredge samples) in southwestern Lake Tanganyika in order to precisely locate new, small-scale coastal protected zones. Detailed echosounding, side-scan sonar, and CHIRP seismic reflection profiling will be conducted within the area of the Nsumbu Tanganyika Conservation Project (Zambia), a region selected for study due to the presence of: (1) an active conservation effort led by the Frankfurt Zoological Society, with the agency for long-term data collection and habitat co-management; (2) five isolated rural fishing villages suffering from a degraded fishery; and (3) areas within a national park marked by intact fish communities.
New acoustic geophysical data, in concert with insights on sediment texture, composition, and radionuclide-derived accumulation rates, will be used to fully characterize the bathymetry, substrate type, and depositional processes of benthic environments in both altered and pristine states. These This data will provide the scientific foundation for defining coastal “no-catch” zones that will be monitored and maintained by local villagers, allowing the health and productivity of fish stocks to recover.
This GWB project will help to improve the productivity of Lake Tanganyika’s fishery in Zambia, securing food resources and improving the health of thousands of villagers in the vicinity of the Nsumbu Tanganyika Conservation Project co-management area. The project team will train villagers, Nsumbu Tanganyika Conservation Project staff, and partners from the Zambia Ministry of Fisheries in marine-type geophysical surveying and benthic habitat mapping, such that the conservation effort can be sustained beyond the project period.
The project’s objectives are tightly aligned with United National Sustainable Development Goal (UN-SDG) 2 (No Hunger), and will greatly expand the use of geophysics in support of inland freshwater fisheries conservation in eastern Africa. Finally, the project will result in geophysical data acquisition, processing and interpretation training for students in both the USA and Zambia, through project outreach and training activities.
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