Data on the composition of the diet of 3 fish species and total species list of the caught fish with annual and monthly densities and biomass for 1985 and 1986 in front of the nature reserve of \"het Zwin\", in the neighbourhood of the Wester Scheldt estuary. The data were digitized by VLIZ from the original report: Van Landtschoote, E. (1986). Ecologisch onderzoek van de visfauna in de kustwateren ter hoogte van de Zwinmonding. BSc Thesis. Rijksuniversiteit Gent. Faculteit Wetenschappen. Laboratorium voor Morfologie en Systematiek der Dieren. Sectie Mariene Biologie: Gent. 109 pp.