Underwater photo of a eelgrass meadow
Photo: Marlene Jahnke

Genetic population structure of Baltic Sea eelgrass - urgent information for conservation of a foundation species under climate change

Research project
Active research
Project size
4 millions SEK
Project period
2021 - 2025
Project owner
Department of Marine Sciences

Short description

The seagrass Zostera marina (eelgrass) is one of the most important habitat-forming species around the Swedish coast. It has declined considerably and is at risk of further decline due to climate change. Management to mitigate further losses must take into consideration the genetic diversity of eelgrass. The project focuses primarily on eelgrass in the Baltic Sea.

Research Focus

With focus on Zostera marina eelgrass meadows in the Baltic Sea we use

  • genomics to provide a baseline of current genetic diversity and connectivity for future genetic monitoring of Baltic eelgrass,
  • oceanographic modelling of current and future climate scenarios, useful for prioritizing meadows for protection and restoration,
  • demographic modelling to assess meadows’ ability to recover and adapt in the future.

Information from the project will help responsible authorities to meet key requirements of national, EU and UN directives and Sustainable Development Goals.

Researchers in the project

Marlene Jahnke, Department of Marine Sciences  – Tjärnö
Personal webpage

Kerstin Johannesson,  Department of Marine Sciences  – Tjärnö
Personal webpage

Per JonssonDepartment of Marine Sciences  – Tjärnö
Personal webpage

Per-Olav Moksnes, Department of Marine Sciences – Gothenburg
Personal webpage

Stefanie RiesDepartment of Marine Sciences – Gothenburg
Personal webpage


Reproductive shoot of eelgrass
Reproductive shoot of eelgrass.
Photo: Marlene Jahnke


Biophysical models of dispersal contribute to seascape genetic analyses. Marlene Jahnke and Per R. Jonsson. Phil. Trans. R. Soc. B, Jan 2022.