The 10th International Symposium on Sturgeon (ISS10)

The Baltic sturgeon (Acipenser oxyrinchus) recovery program has been ongoing for nearly two decades, with increasing numbers of individuals observed in the environment. Yet, the current status of the population remains insufficiently understood. To address this, a monitoring methodology for the Odra estuary was developed and tested, following the guideline provided by the Bern Convention.

The approach integrates three complementary components combining scientific surveys with fisheries collaboration. First, scientific fishing campaigns were carried out in spring and autumn in the Odra River using gillnets (GNS) and drift nets (GND), and in the Pomeranian Bay with bottom trawls (OTB) and GNS. Second, participatory monitoring was conducted with five selected fishers: one in the Odra River (FYK, GNS), three in the Szczecin Lagoon and Lake Dąbie (FYK, GNS), and one team in the Pomeranian Bay operating two vessels (OTB, GNS). These fishers provided detailed data on bycatch, fishing effort, and locations. Third, a wider network of 63 fishers reported incidental bycatch, offering basic information on sites and gear used. Integrating these data sources provided a more complete and cross-validated picture of sturgeon abundance and age structure in the Odra estuary.

Preliminary findings confirm sturgeon presence across the full habitat range, from riverine to marine environments. GNS proved most effective in both scientific and fisher-based catches, while FYK were comparably efficient in the estuarine zone. OTB showed low efficiency and high costs, limiting their suitability for long-term monitoring. Conversely, GND demonstrated strong potential in rivers due to their short sets and high catch efficiency.

This combined methodology standardized scientific fishing, targeted fisher collaboration, and a broad reporting system offers a practical framework for assessing A. oxyrinchus populations. It supports long-term management and conservation of the species, with high potential for transfer and application in other regions of the Baltic Sea basin.