HAKEFJORDEN: The interaction between sea trout and eelgrass will be scrutinized as researchers from the University of Gothenburg, SLU and 8+Fjordar are in the starting blocks of a new Improve project.
We know that eelgrass meadows are important habitats for a range of marine species such as cod and plaice. Now the spotlight is on sea trout, to see if the species’ interaction with eelgrass beds is of the same importance. The method used by researchers from the University of Gothenburg, SLU and the 8+Fjordar team is based on catching trout, marking them with pit-tags and recapturing them later in the fall. To carry out the project, fyke nets and traps are used. Johan Höjesjö from the University of Gothenburg explains:
We hope that the research will lead to a better understanding of trout ecology and better management of the sea trout population…
– We use capture and recapture as a method to see if individuals stay in the same area and measure their growth and condition. Our hypothesis is that many trout smolts stay in the eelgrass meadows because they provide good shelter and good food supply during the first period in the sea,” says Johan Höjesjö.
The experiments are conducted in four shallow bays on the west coast. At Lökebergskile (1) and Källsbykile (2) there is little or no eelgrass at all. At Kåkenäs (3) and Gunnebykile (4) there are healthy eelgrass beds.
Extensive restoration of Hakefjorden
Improve Aquatic LIFE is planning major restoration measures in Hakefjorden. The measures involve repairing destroyed eelgrass beds by planting eelgrass seedlings. By looking at the relationship between sea trout and eelgrass, important conclusions can be drawn when it comes to the restoration of the Hakefjord’s eelgrass beds.
– So far, we have put a lot of resources into restoring freshwater habitats, but we have not worked as much on restoration in the marine environment. For sea trout, this means that in many places we have good conditions for spawning, but that we then lack knowledge about how they manage when they leave the watercourse. We hope that this research will lead to a better understanding of trout ecology and better management of the sea trout population,” concludes Johan Höjesjö.