New policy brief: Establish no-take zones to protect stocks and ecosystems
More no-take zones should be introduced in Sweden to protect fish and crustacean stocks and marine ecosystems. This is according to researchers from Stockholm University and the Swedish University of Agricultural Sciences in a new policy brief. But it is important that the areas are extensive and designed correctly.
Intensive fishing is one of the factors that has the greatest impact on marine ecosystems, and many fish and crustacean stocks are currently severely depleted. Closing certain areas to fishing can have a positive effect, both for the target species and other species aswell, evaluations show.
In a new policy brief, researchers at Stockholm University and the Swedish University of Agricultural Sciences call on decision-makers to introduce more no-take zones. "Properly designed, no-take zones are a good tool to protect and rebuild fish and crustacean stocks. They also have positive effects on ecosystems", the researchers states.
However, seals and cormorants can have a significant negative impact on coastal fish stocks in the Baltic Sea locally, which can lower the effect of protection. Thus, in areas where seals and cormorants are abundant, the recommendation is that fishing closures are complemented by measures to protect coastal fish from predation, such as physical barriers or scarers.
In the first instance, the researchers recommend the introduction of areas that are closed to fishing throughout the year. So-called 'spawning season closed areas', where fishing is only prohibited during the spawning season, may be easier to implement, but are rarely a sufficient protection measure for depleted fish and shellfish stocks.
"Seasonal closures of spawning grounds can have some effects by protecting the most valuable, productive and largest individuals, such as large females from fishing. But if these are fished at other times of the year, the initial positive effects may disappear and the spawning biomass is not rebuilt", they write.
Restrictions on fishing are not always well received by professional and recreational fishermen, the researchers note. “If possible, these and other stakeholders should be engaged early in the process. At the same time, it is important to keep in mind that closed areas can also have positive effects on fisheries in the long run.
"No-take zones act as an insurance policy for fisheries, as they can help prevent stock collapse and counteract the genetic depletion that can result from selective fishing of large individuals".
The policy brief Establish no-take zones to protect stocks and ecosystems” is a co-production between Stockholm University's Baltic Sea Center and the Swedish University of Agricultural Sciences. From Stockholm University, Johan Eklöf, Department of Ecology, Environment and Botany, and Joakim Hansen and Sofia Wikström at the Baltic Sea Center have participated in the process. From the Department of Aquatic Resources at the Swedish University of Agricultural Sciences (SLU Aqua), Ulf Bergström, Charlotte Berkström and Mattias Sköld have participated.
