Fish stock management
The aim of the City of Stockholm's fish stock management is to support recreational fishing, outdoor recreation and local fishing clubs. We do this by releasing salmon, pike, sea trout, pike-perch and crayfish. We also restore habitats that have been damaged by human activity. This is known as habitat restoration and is carried out in rivers, lakes and the archipelago.
Fish stock management mainly focuses on improving conditions for fish to spawn and grow naturally. For example, we:
- create pike wetlands
- add spawning gravel to sea trout streams
- reopen shallow coastal bays in the archipelago.
We work continuously to improve habitats for sea trout. There are around 40 streams in Stockholm County where sea trout spawn. We improve these streams through habitat restoration and by building fish passes.
How does the City of Stockholm manage fish stocks?
The City of Stockholm carries out fish stock management both within the city and in several coastal municipalities across the county, as well as in the archipelago and Lake Mälaren. Much of this work is done in partnership with local associations, municipalities, government agencies and other organisations. Working across geographical and organisational boundaries helps us use resources more effectively and carry out measures where they have the greatest impact.
Many of our larger projects are funded by the European Union and by nature conservation funds managed by the County Administrative Board, the Swedish Board of Agriculture and the Swedish Agency for Marine and Water Management.
We also take part in research projects funded by Formas, the Swedish Research Council for Sustainable Development. These projects focus on reusing surplus rock and stone from infrastructure projects to create new habitats for fish.
From waste to reef, Massa project website (in Swedish)
Invasive species
We also monitor new invasive species in our waters. Examples include signal crayfish, the Harris mud crab and the round goby.
Invasive species can spread through trailered boats, ballast water and the aquarium trade. They can outcompete native species and spread new diseases. You can find more information on our page about invasive species.
We release fish
The City of Stockholm helps release around 150,000 sea trout each year into Stockholm Ström, the archipelago and sea trout streams. Many recreational fishing clubs take part in this work. Together with these clubs, we also work to improve fishing opportunities for people with disabilities.
We also release young pike, pike-perch and crayfish into lakes and the archipelago.
The City works with 15 regional partners, including municipalities, the Stockholm Archipelago Foundation and other organisations, to provide access to fishing and carry out fish stock management and fisheries enforcement.
We also work with the County Administrative Board, HEBA and the Swedish Anglers Association to develop recreational fishing and fishing tourism across the region.