Policy briefs and fact sheets

For a long time, stocks of herring, sprat and cod have been declining in the Baltic Sea. This is partly a result of long-term overfishing, partly related to human-induced changes, such as eutrophication, oxygen depletion and increased temperatures.
Despite increased numbers over the past 20 years, grey seals have not caused this situation. On the contrary, grey seals have important ecological functions and contribute to biodiversity and stability in the food web. Hence increased hunting pressure of seals would not help the recovery of herring, sprat and cod.
Local problems with weak coastal fish populations are best solved locally, with seal deterrence methods and targeted hunting.For a long time, stocks of herring, sprat and cod have been declining in the Baltic Sea. This is partly a result of long-term overfishing, partly related to human-induced changes, such as eutrophication, oxygen depletion and increased temperatures.
Despite increased numbers over the past 20 years, grey seals have not caused this situation. On the contrary, grey seals have important ecological functions and contribute to biodiversity and stability in the food web. Hence increased hunting pressure of seals would not help the recovery of herring, sprat and cod.
Local problems with weak coastal fish populations are best solved locally, with seal deterrence methods and targeted hunting.

Reducing grey seal numbers will not help Baltic fish stocks (layouted pdf)

Reducing grey seal numbers will not help Baltic fish stocks (webb text)

An ambitious EU-ban on PFAS will be an important step toward a cleaner and safer EU, and is likely to have an impact on the use of PFAS worldwide. To be truly effective, it’s important that derogations from the ban are limited in time and scope and provided only to uses where there are no viable alternatives. As PFAS will contaminate the environment for decades, it’s important to provide funding and support for research and development of safer alternatives and technologies to remediate PFAS from contaminated water and soil.

Be restrictive with derogations for uses of PFAS in the new EU-ban (layouted pdf)

Be restrictive with derogations for uses of PFAS in the new EU-ban (webb text)

Be restrictive with derogations for uses of PFAS in the new EU-ban (text version with references)

In advance of the Agriculture and Fisheries Council 11–12 December 2025

The temporary fishing closures decided by the EU are insufficient to protect the increasingly endangered European eel. When the Agriculture and Fisheries Council meets in December, it must take the decisive action advised by ICES for years: a complete fishing ban.

Read the policy memo as pdf:

The EU should follow ICES advice and ban all fishing for eel pdf, 1.5 MB.

Download the appendix as a separate file

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Deep soft bottoms are of vital importance for the functioning of the whole marine ecosystem and long-term carbon storage. These functions may be reduced when they are trawled for commercial fishing and during seabed mining. Still, these habitats are often overlooked when outlining marine protected areas and restricting fisheries and exploitation. EU Member States must better protect deep soft bottoms in the Baltic and North Sea.

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Safeguard ecosystem function and carbon storage capacity in deep soft seabeds

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Early March 2025, the EU Commission organises European Ocean Days in order to gather contributions from stakeholders, experts, and citizens on a new European Oceans Pact, that is to be presented in time for the 3rd UN Ocean Conference in June 2025. Stockholm University Baltic Sea Centre highlights the need for a source-to-sea approach, and that the environmental interest should be guaranteed a seat at the table when the pact is negotiated.

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An Ocean Pact must prioritise the environmental dimension pdf, 104 kB. (103 Kb)

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Baltic Sea Centre's comments on the proposed European Oceans Pact

No-take zones can be an effective tool for protecting fish and crustacean stocks as well as marine ecosystems. However, it is important that these closed areas are properly designed and large enough. Seasonal spawning closures may be easier to enforce, but do not have as strong positive effects as no-take zones.

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Read or download the pdf version:
Establish no-take zones to protect stocks and ecosystems

On 21-22 October 2024, ministers will meet in the European Council to decide, on the basis of Commission proposals, on the fishing opportunities for next year in the Baltic Sea. The decision-making process is preceded by scientific advice from the International Council for the Exploration of the Sea (ICES). Contrary to popular belief, however, this advice represents answers to a series of questions posed by the Commission, not recommendations from scientists to politicians.

This policy memo describes why it's not enough for the politicians to look at the forecasted yield when making decisions on fisheries opportunities for the Baltic Sea.

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Decision-makers need to read the ’fine print’ in ICES advice pdf, 734.3 kB. (734 Kb)

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Decision-makers need to read the ’fine print’ in ICES advice

Stricter national regulations on fertilisation and improved use of manure in agriculture, as well as set-aside schemes, do have measurable effects on the riverine loads of nitrogen to the Baltic Sea, although it can take up to a decade to reach full depletion of legacies in agricultural soils. However, reaching the environmental goals in a cost-effective way, requires more targeted measures to areas where the risk for leaching is high.

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Effective reduction of nitrogen loads requires targeted measures (pdf version)

Effective reduction of nitrogen loads requires targeted measures (web text version)

The Baltic Sea is a unique ecosystem in urgent need of better care. It faces profound challenges, from pollution to overfishing and climate change. Hence, strong action is needed. Fortunately, history shows that when people around the Baltic Sea come together and make the right decisions, significant improvements can be achieved.

In this leaflet, researchers and experts from the Stockholm University Baltic Sea Centre present some key measures to improve the environment of the Baltic Sea, from the Bothnian Bay to the Kattegat. Stronger decisions are needed to reduce emissions of nutrients and hazardous substances, and to ensure the development of a sustainable blue economy with ecosystem-based fisheries management and adequate marine protection.

Read or download the leaflet as pdf:
Key measures for the Baltic Sea 2024 pdf, 13.3 MB. (13619 Kb)

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Key measures for the Baltic Sea

The tightening of the removal requirements in the new Urban Wastewater Treatment Directive is unlikely to have a decisive effect on the nutrient inputs, since most wastewater treatment in the total Baltic Sea drainage basin has improved to the proposed requirements in recent decades. The actions on stormwater overflows and urban runoff could, however, be of importance. Further reductions on nutrient inputs from wastewater could be achieved through measures beyond the directive, such as regulations on private sewages in scattered dwellings and mandatory tertiary treatment of both nitrogen and phosphorus in the whole drainage basin.

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Effects of the new UWWTD on nutrient inputs to the Baltic Sea

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Fact sheet: Effects of the new UWWTD on nutrient inputs to the Baltic Sea

Earlier version

An earlier version of this fact sheet, dated June 2023, treated the Europeans Commission's proposal to new directive. Read the earlier fact sheet here as a pdf:

Effects of the proposed UWWTD on nutrient inputs to the Baltic Sea pdf, 5.4 MB. (5509 Kb)

Read the fact sheet from June 2023 as web text:

Fact sheet: Potential effects of the proposed UWWTD on nutrient inputs to the Baltic Sea

Read the reference version of the June 2023 fact sheet:

Potential effects of the proposed UWWTD on nutrient inputs to the Baltic Sea (refs) pdf, 785.9 kB. (785 Kb)

The restoration and creation of wetlands is being discussed as a way to solve several societal crises. It can mitigate climate change by preventing greenhouse gas emissions, but also reduce eutrophication, prevent floods and droughts and favour biodiversity. However, a single wetland cannot fulfil all environmental requirements; a diversity of wetland types is needed, where the right wetland is put in the right place.

Multifunctional wetlands - reality or utopia? pdf, 3.6 MB. (3705 Kb)

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Horse farms can cause significant leaching of nitrogen and phosphorus and thus contribute to eutrophication. The nutrient load from equine activities should be better taken into account in national calculations and work on eutrophication, so that measures can be taken to reduce it.

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Include nutrient load from horse farms in eutrophication work

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Include nutrient load from horse farms in eutrophication work

A large part of the anthropogenic emissions of carbon dioxide have been absorbed by the oceans, However, many Swedish coastal areas are currently affected by eutrophication, making them a source of greenhouse gases, mainly in the form of methane. Reducing eutrophication is crucial for limiting methane emissions and thus mitigating climate change.

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Reducing eutrophication crucial to prevent coastal methane emissions (layouted pdf with illustrations)

Reducing eutrophication crucial to prevent coastal methane emissions (web text version)

Reducing eutrophication crucial to prevent coastal methane emissions (text version with references)

In the coming decades, ocean acidification is expected to become significant also in the Baltic Sea. For an already stressed ecosystem, it represents an additional pressure, and the cumulative effect of this and other environmental impacts can stress species and reduce biodiversity. Protecting the unique environment and future food production requires both significant reductions in carbon dioxide emissions and measures against eutrophication, overfishing and emissions of hazardous substances.

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Ocean acidification poses another threat to the Baltic Sea ecosystem

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Ocean acidification poses another threat to the Baltic Sea ecosystem

Read on the webb:

Policy brief: Ocean acidification poses another threat to the Baltic Sea ecosystem

Watch or read about our Baltic Breakfast seminar on the subject:

Baltic Breakfast: Ocean acidification – an emerging problem also in the Baltic Sea

The European eel is under acute threat. Many of the measures that could help it are either missing or being implemented too slowly. The most important measures to promote the eel stock are to immediately stop all eel fishing and restocking of eel, and to intensify efforts to remove migratory barriers and open up migratory routes in inland waters. 

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Stop all fishing and restocking of European eel pdf, 1.4 MB. (1426 Kb)

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Stop all fishing and restocking of European eel (with references) pdf, 642.9 kB. (642 Kb)

The ocean has a major impact on the development of the climate, and the ongoing climate summit is the time to highlight this until now undervalued resource, write three professors at Stockholm University in a published Opinion piece addressed to the participants of COP28, 2023.

Read the opinion piece as a layouted pdf:

Time to highlight the ocean’s role for climate mitigation pdf, 63.6 kB.

Through the HELCOM Baltic Sea Action Plan, BSAP, the riparian countries and the EU established a joint view on the environmental problems of their shared sea, and agreed to take specific actions to restore it to a healthy and resilient state. This factsheet describes the scientific basis of the eutrophication segment of the plan; how the political vision of a healthy Baltic Sea can be reached via the basin-wise Maximum Allowable Inputs (MAI) and country-wise Nutrient Input Ceilings (NIC).

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Understanding how eutrophication is quantified in the HELCOM BSAP pdf, 681.7 kB. (681 Kb)

In recent decades, the nutrient loads to the Baltic Sea have decreased sharply. Eventually, this is expected to lead to improvements in the sea, but because large amounts of nutrients are stored in the water and on land, it will take time to see the effects. In order to comply with the commitments in the Baltic Sea Action Plan (BSAP), and simultaneously improve the environment in lakes and watercourses, the countries around the Baltic Sea need to continue to take measures to further reduce nutrient loads from land.

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Policy brief: Further land-based measures are needed to reach eutrophication targets pdf, 1.4 MB. (1403 Kb)

Watch a film that explains why the sea doesn't seem to recover:

The coastal zones are among the most effective areas on Earth at sequestering carbon from the atmosphere. Treated right, these ecosystems are important corner-stones in climate change mitigation, but if degraded, they instead release large amounts of greenhouse gases, re-enforcing global warming. Urgent action is needed to preserve and restore the Baltic Sea coasts and use these systems to work in favor of the climate – not against it.

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Policy brief: Healthy coastal ecosystems are crucial to mitigate climate change pdf, 2.7 MB. (2741 Kb)

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Policy brief: Healthy coastal ecosystems are crucial to mitigate climate change (with references) pdf, 271.3 kB. (271 Kb)

Watch a film where researcher Florian Roth explains his research on greenhouse gases in the Baltic Sea:

Watch a webinar about this topic:

The scientific assessments of the fish stocks in the Baltic Sea are characterized by great uncertainty. In the last five years, the size of the Central Baltic herring stock has been greatly overestimated - which has probably contributed to excessive catch quotas. It is time to introduce a larger buffer for the scientific uncertainty in management and quota decisions.

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Policy brief: Adapt herring fisheries to scientific uncertainty pdf, 2.2 MB. (2254 Kb)

Watch a short film that explains scientic uncertainty in fish stock assessments:

A changing climate makes it even more important to reduce the nutrient supply to the Baltic Sea. In the coming decades, continued reductions in emissions of nitrogen and phosphorus from land will yield better oxygen conditions and improved water quality - even in the face of major climate change. These measures also make the Baltic Sea ecosystem more resilient to the changing climate.

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Policy brief: Measures improve the Baltic Sea environment – even in a changing climate pdf, 860.2 kB. (860 Kb)

Fishing with bottom trawls has extensive effects on marine life and threatens seafloor integrity. It also impacts areas not directly trawled, since suspended sediment can travel far. Recent research on bottom trawling effects points to the need for establishing larger trawl-free areas in all types of habitats to protect sensitive ecosystems and live up to principles of ecosystem-based management.

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Policy brief: Bottom trawling threatens European marine ecosystems pdf, 2.2 MB. (2228 Kb)

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Bottom trawling threatens European marine ecosystems (with references) pdf, 130.5 kB. (130 Kb)

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Increased herring catches close to the Swedish Baltic east coast, and the negative trend for several herring stocks accentuate the need for reduced fishing pressure and more detailed knowledge about herring subpopulation structure.

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Policy brief: Reduce coastal trawling to protect the Baltic herring pdf, 361.7 kB. (361 Kb)

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Urban wastewater treatment plants are important collection points for many chemical contaminants, often called micropollutants, which are widespread in the aquatic environment. Currently, this issue is not being sufficiently addressed by regional policy and EU-wide legislation. The EU’s Zero Pollution Ambition, the Chemicals Strategy for Sustainability and the likely revision of the Urban Wastewater Treatment Directive now provide opportunities to address this issue. Measures to prevent the emissions of micropollutants via wastewater treatment plants are needed both up- and downstream, to ensure policy coherence between EU water and chemicals legislation.

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Call for better management of micropollutants in wastewater pdf, 1.9 MB. (1942 Kb)

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Call for better management of micropollutants in wastewater (with references) pdf, 210.8 kB. (210 Kb)

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If the endangered European eel population is to recover there is an urgent need for a fishing ban, increased environmental monitoring and fewer obstacles to migration. Furthermore, the estimates of spawning biomass and of the impact of coastal fishing used in eel management today should be independently reviewed and revised.

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Policy brief: Fishing ban and more knowledge required to save the European eel pdf, 1.6 MB. (1667 Kb)

Watch a shirt film about how the fishing for eel continues – despite scientists recommendations:

Watch a short film about the eel's lifecycle and the need for a fishing ban: 

Today’s massive flow of chemicals places new demands on risk management. Managing chemicals in groups and introducing mixture risk assessments into all chemicals legislation are two key measures to protect health and the environment.

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Time for smarter and safer chemical management – grouping and mixture risk assessment in European chemicals legislation pdf, 510.5 kB.

More jellyfish but fewer mussels – the expected spread of ocean acidification can have major effects on species composition in the Baltic Sea. It may also make the water slimier and less attractive for swimming. To protect unique ecosystems and future food production, carbon dioxide emissions must be dramatically reduced and measures must be taken against eutrophication, overfishing and releases of hazardous substances.

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Policy brief: Emerging ocean acidification threatens Baltic Sea ecosystems pdf, 1.2 MB. (1187 Kb)

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To meet the challenges of chemical risks in everyday life, risk assessments under the REACH registration process must be improved. One key element in this transformation is to introduce greater transparency.

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Policy brief: European chemicals regulation needs greater transparency pdf, 1.7 MB. (1711 Kb)

In the negotiations for next year’s fishing in the Baltic Sea,the EU Member States could take a number of important decisions to address the cod crisis, such as major reductions in quotas for catches of flatfish, herring and sprat in the southern Baltic.

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Policy brief: For cod’s sake – cut back fishing on herring and sprat pdf, 730.5 kB.