Food resources of Lake Tanganyika sardines: Metabarcoding of the stomach content of Limnothrissa miodon and Stolothrissa tanganicae
Huyghe, C.E.T. (2019). Food resources of Lake Tanganyika sardines: Metabarcoding of the stomach content of Limnothrissa miodon and Stolothrissa tanganicae. MSc Thesis. KU Leuven, Laboratory of Biodiversity and Evolutionary Genomics: Leuven. 59 + Addendum pp. | |
Available in | Author | | Document type: Dissertation
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Keywords | Limnothrissa miodon; Stolothrissa tanganicae
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Abstract | The sardines from Lake Tanganyika in Africa are an important food source for millions of people living around the lake. Stocks of Stolothrissa tanganicae and Limnothrissa miodon have been declining over the years due to overfishing, climate change and other anthropogenic factors. It is important to have ecosystem-based fisheries management (EBFM) to avoid overfishing in the lake. To establish EBFM, it is vital to assess the biology and ecological interactions of the fish. The Lake Tanganyika sardines are an important link between zooplankton and larger fish within the pelagic food web. This study conducted a metabarcoding technique on the stomach content of the sardines to examine their prey item composition. It investigated whether the prey composition in the stomach varied between sardine species, location, season, sex and length. The results showed significant differences in prey composition between species. Limnothrissa miodon had a more diverse diet compared to S. tanganicae. A significant difference was also found between locations and seasons, probably due to the limnology of the lake and the spatial and temporal variability of both biotic and abiotic factors. The diet composition varied with varying standard length for S. tanganicae but not for L. miodon. Genetic material from multiple phyla was found in the stomachs of the sardines, including cnidarian DNA. Future changes in population dynamics of both the sardines and their prey due to overfishing, climate change or other anthropogenic factors could impact the whole pelagic ecosystem. It is important to identify these dynamics and establish international EBFM plans. |
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