Finland’s state forestry and land management company Metsähallitus has published results from a GPS-tracking study of the Baltic gull, intended to inform planning of its Ebba offshore wind project on the country’s west coast. The company commissioned the ecological surveys, which map the seabird’s feeding areas, flight altitudes and movement corridors.
The Baltic gull is listed as globally threatened on the IUCN Red List, with the global population estimated at fewer than 20,000 breeding pairs. Around 75% of those birds breed between Sweden and Finland before migrating to wintering grounds near Lake Victoria in East Africa. The species is a designated conservation feature of the Natura 2000 area in the Raahe archipelago, where the project is sited.
Researchers fitted twelve adult birds with lightweight, solar-powered transmitters in 2025 — six breeding on the islands of Maakalla and Ulkokalla, and six north of Raahe. The devices log each bird’s location, altitude and speed at five-minute intervals. “It is a highly pelagic species that regularly feeds up to 100 km from the nest and flies very long distances on most days,” said ornithologist Martin Hedén, who leads the monitoring. All tagged birds survived the migration to East Africa and back, and a second season of data is now available.
The monitoring is run jointly with the developer of the neighbouring Maanahkiainen project. The two share research data and divide survey areas to avoid overlapping fieldwork, which reduces human presence inside the gull colony. The studies are carried out by the consultancy Sitowise as part of the project’s environmental impact assessment.
Knowing where the birds feed and at what altitude they fly should help Metsähallitus site turbines away from the busiest corridors. Analysis of the 2026 breeding season will follow. For the wider Baltic, where several states are expanding offshore wind in shared and ecologically sensitive waters, the dataset offers a working example of how to weigh renewable-energy targets against seabird protection.
