Parasite biodiversity and trophic dynamics of mangrove fishes in a Senegalese Marine Protected Area

Abstract

Mangrove forests provide important ecosystem services to humans, including protection from flooding and erosion, provision of timber and non-timber forest products, and carbon storage. Fisheries production is perhaps one of the most frequently cited resources. However, fisheries also put substantial pressure on aquatic communities, including fishes and their metazoan parasites. In the present study, we aim to provide the first combined quantitative survey of gut content and parasitic infections of mangrove fishes. To test the effect of fisheries on parasite communities, we sampled the gills (n = 105) and guts (n = 72) of 22 different fish species in the Saloum Delta in Senegal, both inside and outside of a marine protected area (MPA). The Saloum Delta was selected because fish assemblages and trophic dynamics have been extensively studied in the past both inside and outside the MPA. We mainly targeted seven omnivorous and arthropodivorous host species. More than 4,000 parasite specimens were collected, including monopisthocotylans, acanthocephalans, nematodes, copepods, and cestodes—several of which may represent new species. The samples were dominated by monopisthocotylans, acanthocephalans, and trematodes. Due to the currently limited sample sizes per host species, no significant differences in prevalence, infection intensity, or species diversity could be detected. However, this survey provides a first baseline for the parasite biodiversity of West African mangrove fishes and will serve as a reference library for infection, morphological, and molecular data.