Project R-15240

Pathogenic landscape of mangrove ecosystems: implications of overfishing on disease vectors (Research)

Mangroves have historically been considered harbingers of diseases. The role of these habitats in enhancing or controlling disease vectors remains unclear, yet vector predation by fishes has been suggested as a potential ecosystem service. Here, we aim to test this ecosystem service by conducting a spatial analysis of disease impact reported in the literature. Furthermore, mangrove forests, like many marine ecosystems, are threatened by overfishing. We will test direct and indirect effects of overfishing on vector predation by collecting fishes, snails, and crabs in the Saloum Delta National Park (Senegal) in and outside of a marine protected area. We hypothesise that overfishing alters feeding behaviour in targeted fishes and, therefore, affect their feeding rates and health. This changes cause cascading effects in macroparasites, which in turn may also affect predation rates. We assess snail and crab communities, vectors of trematodiases, pre-ingestion through specimen collection and eDNA sampling, and post-ingestion through fish gut content analyses. We will also measure health indices and screen the macroparasites of fishes. Our framework will enable further quantitative studies of vectors and trematodiases to understand their role in mangrove ecosystems as well as their reaction to human-induced environmental changes. This project will be the first to characterise the pathogenic landscape of mangrove forests across multiple vector and pathogen taxa in Africa.

01 November 2024 - 31 October 2025