Volunteers bring kelp forest back in Tromsø city center.

Sørsjetéen—a 200-meter jetty in the heart of Tromsø—was once a barren seafloor, overrun by sea urchins. But thanks to the efforts of the “Kelpers”, one side has been brought back to life. Now, it’s a vibrant underwater jungle teeming with marine life. Time to share the results!

Ada, Adison, América, Amy, Andreas, Andy, Anita, Ann, Anna, Aurore, Barbara, Benedicte, Bjørn, Caitlin, Céline, Clément, Cornelia, Dagny, Dan, David, Delphin, Einar, Elisabeth, Emma, Emily, Giulia, Hans, Ina, Iona, Jacqueline, Jaime, Jamie, Johan, Jony, Julia, Katharina, Katie, Kine, Kristin, Lawrence, Lea, Léo, Leonar, Liga, Linda, Linn, Lola, Louis, Lucas, Maren, Maria, Michael, Nico, Niklas, Nikolai, Nora, Pauline, Robert, Rose, Saga, Sigrid, Sigurd, Stefano, Terje, Theresa, Thorvid, Todd, Tuomas, Vegar and Øystein.

These are the heroes of Sørsjetéen! Without their dedication, Sørsjetén would still be an urchin-covered biological desert, once reaching up to 200 sea urchins per square meter. From October 2023 to April 2025, these fearless Kelpers, on land and underwater, braved icy waters, bouncing waves, leaky suits, and the occasional jellyfish sting to help transform this stretch of seabed into a thriving marine sanctuary, right in the heart of Tromsø.

Rissa's Kelpers restoring kelp forest along Sørsjetéen in April 2025.

During the 16 events organized in that period, cumulatively, 130 Kelpers contributed their time to the cause (92 in the water and 38 on land).

That is over 90 hours of collective effort to bring life in the sea! (thank you Jamie for digitalizing all the field notes!).

The results are stunning, and we’re incredibly thankful to photographers and filmmakers Ann Cools, Clément Brun, Jacqueline Kärcher, Liga Sirava and Sigurd Vaagland for capturing the transformation with such talent and creativity.

Sørsjetéen is now a refuge and nursery for many species of fish.

Close monitoring and citizen science

Tracking our restoration efforts along the jetty is a top priority.

That’s why we carefully record the number of volunteers, the time we spend on land and in the water, and the number of urchins we remove. This data helps us understand the true impact of our work.

At Sørsjetéen, nature surprised us: the seaweed and kelp bounced back so quickly that our initial methods to document the changes couldn’t keep up! But we learned our lesson. At our next site in Telegrafbukta, thanks to our collaboration with researchers from the Arctic University of Norway-UiT, we’re stepping things up with a more refined scientific approach to better capture the return of marine life.

Citizen science and observations of the marine life along Sørsjetéen.

Maintaining the balance

Fortunately, we don’t need to seed or plant kelp and seaweed at our restoration sites. Their spores already drift through the ocean, settle naturally, and flourish on rocks once freed from overgrazing. However, sea urchins continue to move in, drawn by the sudden abundance of food. In that sense, Sørsjetéen remains a promising, but still small-scale, effort. It proves that kelp forests can recover when urchin numbers are reduced, but also highlights a key challenge: without natural predators, sea urchins remain overly dominant.

From urchin barren to kelp forest along Sørsjetéen.

Events for everyone

Lending a hand from land is always welcome, there’s no need to dive in to make a difference!

Besides, with our underwater drone, anyone can explore the vibrant kelp forests from the shore. It is an accessible way for very young volunteers and curious passersby to get a glimpse of the underwater world and see the magic unfolding just below the surface. By the way, the drone is lent to Rissa Citizen Science by a generous supporter and we are infinitely grateful to him!

Exploration with an underwater drone along Sørsjetéen.

Join the next event!

Whether you've decided to dedicate your life to kelp forest restoration, or you are just curious to meet the Kelpers, or itching to try out our underwater drone, you're warmly invited to join our next event. Sign up through Rissa’s website! It’s free to attend, and you’ll be greeted with a waffle and a cup of hot coffee or tea.

Come join the adventure!

Rissa's kelpers on Sørsjetéen in April 2025.