This study, conducted on the Cap-Vert peninsula (Dakar, Senegal), examines the epifaunal communities associated with macroalgae, revealing significant variations depending on the species of algae. In 2023 (in situ samples), amphipods dominated most macroalgae, particularly Coralina officinalis (29.40%) (Rhodophyceae), Chlorophyceae (30.38%), and Codium sp. (29.38%) (Chlorophyceae). In 2022, copepods (76–92%) were most abundant on Sargassum spp. and Ulva spp., which had washed up on the beach. A significant link between epifaunal abundance and macroalgae species highlighted their ecological interdependence. These findings are of relevant interest for West Africa’s blue economy, where the growing exploitation of wild macroalgae could disrupt these ecosystems. Sustainable management must take into account epifaunal species, particularly those found on structurally important macroalgae (e.g., Corallina sp., Codium sp.). The study recommends including macroalgae-epifauna associations in biodiversity inventories, particularly in marine protected areas, and continuing research on influencing factors (e.g., algal morphology, environmental conditions). Mass strandings of Sargassum spp. and Ulva spp. can cause mortality in marine larvae and eggs, leading to a local reduction in recruitment. Future research integrating these conclusions could allow a more detailed analysis of the epifauna on macroalgae. Ecosystem approach is essential to strike a balance between economic development and biodiversity conservation.

This study from Cap-Vert (Dakar, Senegal) examines epifaunal communities associated with macroalgae, revealing key variations based on algal species and sampling period. In 2023 (in situ samples), amphipods (24–30%) dominated, particularly on Corallina officinalis (Rhodophyceae), while 2022 (beached samples) showed copepods (76–92%) as the most abundant on Sargassum and Ulva spp. The highest epifaunal density was recorded on 2023 Ulva spp. (Chlorophyceae). Univariate analysis confirmed a significant link between epifaunal abundance and macroalgae species, highlighting their ecological interdependence. These findings are critical for West Africa’s blue economy, where expanding macroalgae exploitation could disrupt these ecosystems. Sustainable management should account for species-specific epifaunal dependencies, particularly for structurally important algae (Corallina, Codium). The study recommends integrating macroalgae-epifauna associations into biodiversity inventories, especially in marine protected areas, and further research on influencing factors (algal morphology, environmental conditions). An ecosystem-based approach is essential to balance economic development and biodiversity conservation.