A person wearing a helmet is standing on a boat, holding a black receiver.
RESEARCH PROJECT

Baltic Sea Tracking Network

KEY POINTS
  • Large-scale infrastructure for fish tracking in the Baltic Sea
  • Network for collaboration and data sharing
Updated: September 2026

Project overview

The official name of the project:
Baltic Sea Tracking Network (BSTN)
Project start: January 2025
Project manager: Gustav Hellström
Contact: Johan Leander
Funded by: The Kempe Foundations, Ocean Tracking Network (OTN), Voice of the Ocean (VOTO), Swedish Agency for Marine and Water Management (HaV).

More related research

Global goals

  • 14. Life below water

Short summary

Our infrastructure creates new opportunities to study fish migration and survival. Through strategically placed acoustic receivers, tagged individuals can be tracked across areas far beyond where they were originally tagged. Particular focus is placed on species such as salmon and brown trout.

Acoustic telemetry makes it possible to track the movements of individually tagged fish over time. The backbone of BSTN consists of acoustic receivers deployed along two lines between Sweden and Finland, in Kvarken and the Åland Sea. These strategically located detection gates register tagged fish moving between the Bothnian Bay, the Bothnian Sea and the Baltic Proper.

BSTN complements existing regional and local receiver networks and helps connect different acoustic telemetry initiatives around the Baltic Sea. A particular focus is on Atlantic salmon and brown trout and their migrations from rivers to the open sea and back. At the same time, the infrastructure can be used for other species and research questions, enabling movements to be studied over considerably larger geographical areas than is normally possible within individual studies.

A network for collaboration and data sharing

A central idea behind BSTN is that the infrastructure should provide benefits beyond individual research projects. By sharing detection data from BSTN through the Ocean Tracking Network (OTN) and European Tracking Network (ETN), researchers and managers can find out whether fish tagged in independent projects have been detected by BSTN receivers.In this way, BSTN, together with other receiver networks, creates opportunities to track fish across both geographical and administrative boundaries. The aim is for the resulting knowledge to contribute to a stronger scientific basis for the management and conservation of migratory fish populations in the Baltic Sea.

BSTN is operated jointly by the Swedish University of Agricultural Sciences (SLU), the Natural Resources Institute Finland (LUKE) and MidOcean via Voice of the Ocean (VOTO). 

Project news

SLU launches large-scale fish tracking – aiming to provide new insights about fish in the Baltic Sea

Map showing Sweden, Finland and the Baltic Sea. A red line runs between the countries in two places, marking the locations of the receivers.
The red lines show where the receivers are placed in a row between Sweden and Finland.

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