It has long been known that eelgrass beds are extremely important in many ways, not least as nursery grounds for many fish species. Now researchers are finding out how important they are specifically for sea trout. A new research project – and a short film – takes us to Hakefjorden, where the hidden habitats of the sea reveal their importance.
Eelgrass beds are much more than green mats on the seabed. They are important ecosystems in the marine environment. They act as nurseries and nursery grounds for many fish species, where the vegetation provides shelter and creates habitats for a variety of small animals. Through its roots, eelgrass stabilizes bottom sediments and contributes to clearer water. Eelgrass meadows can also store large amounts of carbon, while absorbing nutrients and preventing eutrophication. In addition, they protect our coasts from erosion by dampening waves and retaining sediment.
Sea trout is one of the fish species that use the eelgrass beds,
Sea trout thrive in eelgrass
Sea trout is one of the fish species that utilize eelgrass meadows, but there has been no knowledge of how important the eelgrass environment is specifically for that fish species. A collaborative project under Improve Aquatic LIFE will find out.
In the video below, we follow researchers to Hakefjorden in Bohuslän, where they investigate the presence of sea trout in areas with eelgrass.
Sea trout thrive in the eelgrass. Photo: Mathias
Catching trout is tagged and provides knowledge
Trout are caught in gentle traps, weighed, measured and fitted with a Passive Integrated Transponder (PIT) tag – a small electronic chip used to tag and identify the fish. The tag can be left in place for the life of the fish without needing to be replaced. This allows researchers to map how sea trout use the world of eelgrass.
– “It is very exciting how we can now link the trout’s life cycle with what it looks like in the sea and thereby gain even more knowledge about how important the eelgrass beds are,” says Johan Höjesjö, Professor of Ecological Zoology at the University of Gothenburg.
In the near future, you will be able to watch more movies on the project’s movie channel