Using a side‐selective fyke net barrier to research fish assemblages in the transitional and transboundary waters of the Vistula Lagoon,southern Baltic

The natural and territorial conditions of the Vistula Lagoon render it difficult to perform repeatable and representative investigations of fish assemblages. The changeability of hydro‐meteorological conditions (wind strength and direction), hydrological conditions (shallowness, the thickness of bottom sediments, submerged barriers, wavy motion) and the social and transboundary conditions mean that most standard monitoring methods and fish migration studies are either impossible to apply or produce unsatisfactory results. This current work presents the results of long‐term observations of fisheries deploying a side‐selective fyke‐net barrier. The fishing gear was deployed parallel to the border in the Vistula Lagoon in order to determine the difference in the movement of fish from the Polish and Russian sides of the lagoon. Thanks to the co‐operation with fishermen, data was collected from catches during the 1995–2002 period; this permitted the identification of variations in relative abundance and the dominant direction of fish migrations during the fishing season. The highest statistically significant differences between the fishing results on either side of the barrier were noted in the autumn months of September and October.