Temporary no-take zones are increasingly introduced in Sweden as a fisheries management tool to restore populations of specific target species. A paper published in the journal Marine Policy by CERE researchers show that cost-benefit analyses for the two no-take zones are positive in all scenarios relating to the most realistic case of no opportunity costs, i.e., assuming that all fishing activity could be relocated to adjacent areas without cost during the closed period. (Click on headline to read more)

The paper presents a cost-benefit analysis of two real case temporary no-take zones closed during a 5-6 year period in the coastal zone of the Baltic Sea, Gålö in the Stockholm archipelago and the larger Storjungfrun-Kalvhararna in the Baltic Sea north of Stockholm. Gålö was closed between 2010 and 2015, while Storjungfrun-Kalvhararna, was closed between 2011 and 2016. In Gålö the target species were pikeperch (Sander lucioperca), northern pike (Esox lucius) and perch (Perca fluviatilis), while in Storjungfrun-Kalvhararna the target species was European whitefish (Coregonus maraena).
Showing the no take zones in the Baltic Sea
Fig. 1. Map showing temporary no-take zones, spawning closures and reference areas in (A) Storjungfrun-Kalvhararna and (B) Gålö, Baltic Sea.

We used scenario analysis to account for uncertainty in both the biological and economic effects. A sensitivity analysis was added for certain key parameters. A key uncertainty is what happens to fishing activity during the closed period. In the absence of detailed data on this variable, we first assumed that all fishing activity could easily be relocated to adjacent areas without cost during the closed period. This is not an unreasonable assumption, given that the areas were small and given that there are many alternative fishing sites along the coast. As an extreme case comparison, we assumed that no fishing activity could be relocated to other areas during the closed period.

If fishing could be relocated to other areas during the closed period, the results of the cost-benefit analyses for the two no-take zones were then positive for all scenarios. If no fishing activity could be relocated one of the no-take zones – Gålö - then exhibited a negative net result for most scenarios. For the other area - Storjungfrun-Kalvhararna - the net result was positive even when this maximum opportunity costs of temporary lost fishing opportunities were included, largely depending on the strong positive change in the value of commercial fishing.
By demonstrating potential costs and benefits of using temporary no-take zones in fisheries management this study may contribute to policy making, as well as to creating acceptance from stakeholder groups that incur short-term costs from closing areas to fishing.

Bostedt, G., Berkström, C., Brännlund, R., Carlén, O., Florin, A.-B., Persson, L. & Bergström, U. (2020) Benefits and Costs of Two Temporary No-take Zones. Marine Policy, In press.

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