Swedish Agency for Marine and Water Management

In 2001, the Government authorised the construction of an offshore wind farm at Lillgrund (48 wind turbines with 2.3 MW generators). The Lillgrund wind farm is located in the Öresund Strait in the southwest Sweden and it connects the brackish Baltic Sea with the Kattegat and North Sea area. In 2002, the Environmental Court defined the final terms and conditions for the wind farm development and the extent of the monitoring programme required. Lillgrund wind farm has been operating since 2008 and is currently the largest investment in offshore wind power that is in operation in Sweden. The National Board of Fisheries conducted a monitoring programme in the area in the years before (2002–2005) and after (2008–2010) the construction of the wind farm; a base line study and a study when the wind farm was operational, respectively. The aim was to investigate the impact of the wind farm, when operating, on the benthic (bottom-living) and pelagic (open-water living) fish as well as on fish migration. These studies have partly been integrated into work conducted as a part of the research project Vindval, funded by the Energy Agency. Throughout the project period, regular contact has been maintained between the National Board of Fisheries and Vattenfall (which owns and operates the wind farm), as well as with the regulatory authority (County Administrative Board of Skåne). The main results can be summarised in a number of points below: 

Acoustics (sound) 

• The overall sound energy from the wind farm under water, is mainly generated by vibration from the gearbox.

• An analysis of the sound pressure level for the wind farm area, showed a correlation between noise level and the number of turbines in the wind farm (the so called park effect), where each individual turbine helps to increase the overall noise level in the area.

• Sound measurements from Lillgrund wind farm showed that noise levels within a distance of 100 metres from a turbine at high wind speeds are high enough to be a risk for some species of fish to be negatively affected, e.g. in the form of escape behaviour, or masking of vocal communication between individuals.

• Stress reactions can also occur at distances of more than 100 metres from a turbine. This is due to the fact that the noise from the turbines is continuous and louder than the ambient noise levels within some frequencies.

Benthic (bottom-living) fish

• The development of the fish community in Lillgrund was similar to that observed in the reference areas during the study period. For the wind farm as a whole, no effect was observed on the species richness, species composition or quantity of fish.

• Several species of bottom-living fish showed an increase in abundance close to the individual wind turbines compared with further away, especially eel (yellow eel) (Anguilla anguilla), cod (Gadus morhua), goldsinny wrasse (Ctenolabrus rupestris) and shorthorn sculpin (Myoxocephalus scorpius). The results more likely reflect a redistribution of fish within the wind farm, rather than a change in productivity or migration from surrounding areas. The increase in abundance is probably due to the wind turbine foundations providing an opportunity for protection and improved foraging.

• The distance within which an increased abundance could be observed was estimated for different species to be between 50–160 metres from a wind turbine.

Pelagic (open-water living) fish

• There was a dramatic increase in commercial fishing for herring (Clupea harengus) north of the Öresund bridge, in contrast to the south of this line, where it practically completely stopped during the first years of operation of the wind farm. This change may imply that the Rügen herring migration was affected by the Lillgrund wind farm. Due to the fact that there were other factors in addition to the wind farm contributing to the herring movements, it proved difficult to identify any correlation.  Fish migration

• According to the study, the wind farm at Lillgrund is not a definitive barrier for the migration of silver eels (Anguilla anguilla) that migrate through and close to the wind farm area. The same proportion of the tagged and released silver eels (approximately one-third), passed the transect line with receivers, both before the wind farm was constructed (the baseline period) and after it was in operation.

• There was no statistical difference indicating any alterations in the migration period for silver eel, but there was a tendency towards the migration taking longer at higher productivity (>20% of maximum effect) which could indicate that some eels were affected by the wind farm. There was a tendency towards the eels being recorded on fewer occasions than expected within the wind farm when functioning at low productivity (<20 %) and on more occasions than expected when functioning at higher productivity (>20 %), which may indicate that some individuals are less able to navigate past the wind farm at higher production rates.   

Conclusions

The study at Lillgrund has resulted in an increase in knowledge of how offshore wind farms can affect fish, which is very valuable. Even within an international perspective, there are very few studies of offshore wind farms in operation.  Three years of monitoring the effects of the wind farm on fish and fisheries is only a relatively short period. Some of the most significant results however, include the fact that some bottom-dwelling fish were attracted to the fundaments of the wind farm and the associated rocky protection layer (reef effect). In addition, an increasing noise level in the Öresund environment was observed and the results of the eel tracking may indicate that the migration pattern of some eels was, to some extent, affected by the wind farm. There is a need for caution however, when applying the results in other marine areas and on a larger scale. Lillgrund wind farm is one of the first large-scale wind farms and is located in an area with frequent and noisy shipping traffic as well as frequent and large fluctuations in external parameters such as salinity and currents. A key gap in our knowledge, despite these studies, is the lack of long term monitoring, to evaluate the long term ecological impacts of the reef effects observed. It would be ideal to re-visit the wind farm after a number of years to see how the fish populations have developed over the longer term, and see whether the observed accumulation of certain fish species near the structures continues, and if quantitative effects on the whole area are also are evident. Studies looking at whether noise as a physiological stress, can affect the fish species that live or pass through the wind farm environment are also required. In addition it would be useful to implement further studies, especially in the Baltic Sea, with regard to the cumulative impacts on migratory fish such as silver eels. The full report is available as a PDF in English.

In 2001, the Swedish Government authorised the construction of an offshore wind farm at Lillgrund in the Öresund Strait between Denmark and Sweden. In 2002, the Environmental Court defined the final terms and conditions for the wind farm development and the extent of the monitoring programme required.  Lillgrund wind farm came into full operation in 2008, and is currently the largest offshore wind farm in operation in Sweden.  The Swedish National Board of Fisheries conducted a monitoring programme, in the area, in the years before (2002–2005) and after (2008– 2010) the construction of the wind farm; a base line study and a study when the wind farm was operational, respectively. No investigation was conducted during the construction phase. The aim was to investigate the impact of the wind farm during the operational phase on the benthic and pelagic fish as well as on fish migration. These studies have partly been integrated into work conducted as a part of the Vindval Research Programme, funded by the Swedish Energy Agency.

Acoustics (sound) 

• The overall sound energy from the wind farm under water is mainly generated by vibration from the gearbox.

• An analysis of the sound pressure level for the wind farm area, showed a correlation between noise level and the number of turbines in the wind farm (the so called park effect), where each individual turbine helps to increase the overall noise level in the area. 

• Sound measurements from Lillgrund wind farm showed that noise levels within a distance of 100 metres from a turbine at high wind speeds are high enough to be a risk for some species of fish to be negatively affected, e.g. in the form of direct escape behaviour, or masking of vocal communication between individuals. 

• Stress reactions can also occur at distances of more than 100 metres from a turbine. This is due to the fact that the noise from the turbines is continuous and louder than the ambient noise levels within some frequencies.   

Measurements of the underwater noise levels were carried out at varying distances from individual turbines, from longer distances away from the entire wind farm as well as within a reference site (Sjollen) 10 km north of the wind farm. The results show that the wind farm produces a broadband noise below 1 kHz as well as one or two tones where the 127 Hz tone is the most powerful (vibrations from the first stage in the gear box). The majority of the overall underwater sound energy from the wind farm lies around the tone of 127 Hz.  The maximum noise levels, generated by the wind turbine, working at full production (12 m/s), at 1 m were 136 dB re 1µPa(RMS) for the dominant tone of the turbine which was 127 Hz (integrated across 123–132 Hz) and 138 dB re 1µPa(RMS) at the full spectrum (integrated across 52–343 Hz). At a distance of 100 m from the turbine, the noise levels are reduced to 104–106 dB re 1µPa(RMS) across the full spectrum, which is close to the locally measured ambient noise in the Öresund Strait, but the noise level was still around 23 dB above the background level for the 127 Hz tone.

An analysis of the sound pressure level for the wind farm area showed a correlation between noise level and the number of turbines in the wind farm (called the park effect). Close to the wind farm (<80 m), the noise environment was dominated by the individual wind turbine with a calculated sound propagation loss of 17•log (distance). At greater distances (80 m to 7000 m) the sound propagation loss was non-linear and less than 17•log (distance). This is explained by the fact that the other turbines in the wind farm contributed to the total noise level. At even greater distances (>7 km) the entire wind farm functioned as a point source and the sound propagation loss was once again measured as 17•log (distance). The noise levels equivalent to those recorded and calculated from Lillgrund wind farm have not been shown to cause any physical injury to fish according to the current published scientific literature. It was only within some 100 metres from a turbine at high wind speeds that the noise levels were high enough to result in the risk of negative effects on some species of fish in the form of direct escape behaviour or possible masking of communication. The response depends upon the individual species’ sensitivity to sound. Fish have been shown to become stressed when they find themselves in a consistently noisy environment, which in turn can result in for example, lower growth rates or can have an impact on reproduction. Stress in general can also, in combination with other negative factors, make them more susceptible to disease etc., due to an impaired immune system. Animals can choose however, to remain in an area despite the disturbance, if the area is sufficiently important for their survival or reproduction.  Based on the calculated sound propagation around the wind farm, salmon and eel could theoretically detect the 127 Hz tone at 250 m and 1 km distances respectively at a productivity rate of 60 and 100 %, which is equivalent to a wind speed of approximately 6 and 12 m/s. The calculated distances would be limited by the hearing ability of both fish species and not the background noise levels in the Öresund Strait. For herring and cod, the theoretical detection distance was calculated to be between 13 and 16 km respectively for a production rate of 60 and 100 %. This distance should have been greater, but is limited for these species due to the ambient noise levels in the area. These calculations indicate that fish can potentially detect sound from the wind farm at relatively long distances. Local variations with regard to depth and physical barriers such as peninsulas, e.g. Falsterbonäset in the southern end of the Öresund Strait, can however, have a large impact on the actual sound propagation. 

Benthic Fish

• The temporal development of the fish community in Lillgrund was similar to that observed in the reference areas during the study period. For the wind farm as a whole, no effect was observed on species richness, species composition or on the abundance of fish. 

• Several species of fish however, showed an increase in abundance close to the wind turbines compared with further away, especially eel (yellow eel) (Anguilla anguilla), cod (Gadus morhua), goldsinny wrasse (Ctenolabrus rupestris) and shorthorn sculpin (Myoxocephalus scorpius). The results reflect a redistribution of fish within the wind farm, rather than a change in productivity or migration from surrounding areas. The increase in abundance is probably due to the wind turbine foundations providing an opportunity for protection and improved foraging. The distance within which an increased abundance could be observed was estimated, for different species, to be between 50– 160 metres from a wind turbine. 

• Fish distribution may to some extent have been influenced by the local acoustic environment, as a lower degree of aggregation close to the wind turbines at higher noise levels. The effect was most obvious for eelpout and eel (yellow eel). No response was seen for cod in relation to sound levels.   

Changes in the species composition of the fish communities over time were studied in comparison with two reference areas. Of these, the northerly reference area (Sjollen) had a larger marine component than the southern reference area (Bredgrund). The species composition at Lillgrund had similarities with both of the reference areas.  The results from fish sampling with fyke nets and gill net series indicate that there have been no significant changes in the number of species, the species composition or the fish abundance after the wind farm was built, looking at the wind farm as a whole. Some changes have however been noted in relation to individual species. An increased catch of shore crab and eel (yellow eel) was observed during the first two years of production, but not in the third year. The catch of eelpout increased in all areas during the period studied, but to a slightly lesser extent at Lillgrund when compared to the reference areas. For the other species, the changes observed at Lillgrund were similar to at least one of the reference areas. These results suggest that the fish communities within the wind farm were primarily affected by the same general environmental conditions as the fish communities within the reference areas, rather than by the effects of the wind farm.  An analysis of the distribution patterns of fish close to the turbines showed an increased abundance in the immediate vicinity of the wind turbines in four of the eight species of fish studied: specifically shorthorn sculpin, goldsinny wrasse, cod and eel (yellow eel). The effects were seen already after the first year and were similar over all three years studied. An effect was also identified for eelpout, but only in 2010. The aggregation effect was seen within a distance of 50–160 metres from the wind turbines, different for the different species.  A comparison of the relative effect of different factors, based on the data from an extended survey in 2010, showed that the observed distribution pattern could be explained to a larger extent by the presence of the turbines rather than the underwater topography of the area. The analysis also indicated weak effects of the local acoustic environment on fish distribution patterns, with a reduced presence of fish at higher noise levels. The response was strongest for eelpout and eel. No response in relation to noise level was seen for cod. For shorthorn scuplin and common shore crab a response was seen only 11 Swedish Agency for Marine and Water Management Report 2013:19  during the autumn. The magnitude of the effect of noise was, however, lower than the aggregation effect. Hence, fish aggregated close to the wind turbines in all conditions, but the effect was weaker when the noise levels were higher. It is recommended that the the wind farm area is reinvestigated after a number of years to follow the long-term development of the fish populations, and to see if the aggregation effect observed continues and potentially also increases over time. A prerequisite for a long term positive development of fish abundance is that the removal of fish, such as from fishing or predation by marine mammals and fish-eating birds, does not increase in the area. 

Pelagic Fish

• There was a dramatic increase in commercial fishing for herring north of the Öresund Link (close to the north of the wind farm) in the first years of operation of the wind farm, in contrast to south of the bridge that forms a part of the Öresund Link, where it virtually completely stopped. This change may imply that the Rügen herring migration was affected by the Lillgrund Wind Farm. Due to the fact that there were other factors in addition to the wind farm contributing to the herring movements, it proved difficult to identify any correlation.   

The evaluation was based on catch statistics from the commercial fisheries in the Öresund Strait (ICEs subdivision SD 23) and fisheries independent statistics from ICES for adult herring (Rügen herring) (ICES subdivision SD 21–23, western Baltic Sea and southern Kattegatt) and density of juvenile fish (ICES subdivision SD 24). There was a dramatic increase in commercial fishing for herring north of the Öresund Link in the first years of operation of the wind farm, in contrast to south of the bridge where it virtually completely stopped. The reason may be largely explained by the regulations banning drift-net fishing and a favourable market for herring, but potentially also because of the Öresund Link which was completed in 2000.The potential impacts of the wind farm are therefore difficult to distinguish from the impacts of these other factors because detailed resolution in the catch statistics are missing from the years before 1995 prior to the start of the building work on the Öresund Link. The statistics independent of commercial fishing from ICES showed no significant correlation between the density of herring juveniles in the western Baltic Sea and the number of adult herring (3 years old or more) in the following years in the Öresund Strait (ICES SD 21–24). There was however a weak tendency towards a negative development of the fish population over the period 1993 – 2010. The presence of Rügen herring and their migration through the Öresund Strait is likely strongly influenced by the fact that the population shows large fluctuations between the years. In addition, there is a possible overlapping effect on the soundscape from the wind farm and the Öresund Link, which has been in use since 2000.  Overall, the variety of factors together mean that it is difficult to identify any clear results with regard to if the migration of Rűgen herring is influenced by Lillgrund wind farm.

Fish Migration 

• According to the results from this work, the wind farm at Lillgrund is not a barrier for the migration of the eels that come into contact with it. An equally large proportion of the tagged and released silver eels (approximately one third) passed the transect line with receivers, at Lillgrund both before the wind farm was constructed (baseline study) and after it was in operation. 

• There was no statistically significant difference indicating any alteration in the migration speed of eels, but there were occasional longer migration times when the wind farm was working at higher levels of production (>20 % of maximum) which may indicate that some eels are affected by the wind farm. The fact that the eels also showed a tendency towards being noted on fewer occasions than expected within the wind farm at low productivity (<20 %) and on slightly more occasions than expected at higher productivity (>20 %), could indicate that they have greater difficulty in navigating past the wind farm at higher levels of productivity than lower. 

The impact of the wind farm on migration was studied via tagging of migrating silver eels. In total, 300 acoustically individually tagged eels were included in the study and of these, 100 contributed with useable information. The baseline study period started on a small scale in 2001 and ended in 2005. The majority of the eels were tagged and monitored during the production period (2008– 2010). All tagged silver eels were released south of the wind farm. 

The results showed that an equally large proportion of the tagged and released silver eels; approximately one third, passed a transect with receivers at Lillgrund wind farm, both during the baseline period 2001–2005, and when it was in production 2008–2009. The greatest proportion of eels passed through the deeper part of the transect by the navigation channel Flintrännan close to the Danish border at Drogden during the production phase (31 %) and baseline period (43 %). A somewhat larger proportion of the eels were registered passing the most easterly part of the transect, close to Klagshamn, during the production phase (14 %) compared with the baseline period (5 %). A behaviour which occurred during the production phase, was that some individuals moved back to the release site, after being in the vicinity of wind farm. The most commonly observed behaviour during the study in 2010 was that an eel was registered moving south of the wind farm in a more or less northerly direction, but without being registered to the north of the wind farm.  The range in the time taken for the movement of the eels from the release site to the transect running through the wind farm was very great, from four to more than 1000 hours. There was no statistically significant difference in the time taken to travel, between periods with low production (<20 % of maximum) and periods with high production (>20 %) or for individuals which passed through or outside of the wind farm.  Even if the eels did not show any statistically significant behaviour, changes in movement patterns may occur for some individuals. The fact that there was a tendency towards longer periods of time taken for movement at higher production levels (not statistically significant) (>20 %) could indicate that some individual eels are influenced by the wind farm. The proportion of eels that took more than a week (168 hours) to make the journey was 48 % during the period with higher production (>20 %) compared with 28 % at lower production. No significant difference in the proportion of passes within or outside of the wind farm respectively could be shown. The eels showed however, – a tendency of being recorded on fewer occasions than expected inside the wind farm at low production levels (<20 %) and on more occasions than expected at higher production levels (>20 %). The irregularities in the proportions, compared with the expected result, could indicate that individual eels stayed longer in the wind farm when it was functioning at higher productivity. If the eels discover the wind turbine only when they are very close and do not change course, then other factors such as the speed of the current across the shallow marine areas become significant and can mean that the time spent in the area is shorter and records fewer. At high productivity, the eels may hesitate and/or divert their course and be recorded from close to or within the area, to then be recorded on the transect outside of the wind farm.  The mechanisms that lie behind the possible impact from the electromagnetic field or the noise pattern are difficult to distinguish, as both can have an impact on the same areas. Travelling speed showed no linear relationship with the level of production in the wind farm. 

Conclusions

The study at Lillgrund has resulted in an increase in the understanding of how offshore wind farms can affect fish, which is very valuable. Even within an international context, there are currently very few experience-based studies of offshore wind farms in operation.  The results from three years of monitoring during the operational phase show that the effects of the wind farm on fish populations and fishing were limited. One of the clearest results showed that some benthic fish species were attracted to the foundations of the wind turbines with their associated scour protection (reef effect). In addition, the effect on the local noise environment in the form of increased noise in the Öresund Strait was documented. The results of the eel tracking study may indicate that some eels are influenced by the wind farm on their migration. Some care should be taken however, when applying the results of these studies in other offshore environments and on a larger scale. The monitoring has only been carried out for three years and thus reflects only a short-term perspective. Lillgrund wind farm is also one of the first large-scale wind farms and is situated in an area with regular and noisy shipping traffic and both frequent and large variations in environmental factors such as salinity and currents.  A key knowledge gap that remains after the completion of this work is the lack of studies over a longer period of time, to help identify the long term ecological effects of, for example, the reef effect. Ideally, the wind farm should be re-visited after a number of years to see how the fish populations have developed over the longer term, and see if the observed aggregation of certain fish species close to the wind turbines continues, and to possibly see if any quantitative effects have taken place. Studies are also required in relation to how stress may affect fish species/individuals which choose the reef-like foundations and their noisier environment. Additional studies, primarily for the Baltic Sea, are also required to establish if there are any cumulative effects on migratory fish such as silver eels.

Humans benefit greatly, and in many ways, from marine ecosystems. Marine ecosystems produce oxygen, atmospheric water and food, and they give inspiration, recreational opportunities and much more, often for free. Referring to the benefits for people from marine ecosystems as ecosystem services is a way to make them visible to society. Ecosystem services provide a complementary perspective to the natural scientific aspects, and are used in management, policymaking and the public debate regarding the sea. Valuing ecosystem services can initiate abatement of environmental problems in cases when these have a societal cost which is not reflected in market values. Ecosystem services as a concept has become increasingly influential in the marine environmental policy. Ecosystem services are for instance included in the EU’s Marine Strategy Framework Directive and a number of other international directives and agreements. This report aims to classify the status of marine ecosystem services in Sweden, as well as to evaluate their main anthropogenic pressures. The status classification is made with regard to the three different marine sub-regions of the Swedish economic zone: the Kattegat and Skagerrak, the Baltic Proper, and the Gulf of Bothnia. The three status classes applied are good, moderate and poor. Several of the ecosystem services are classified using indicators or environmental quality norms, and this approach is likely to be central in future assessments of ecosystem services. Other ecosystem services are status classified based on recent literature within the respective fields. Anthropogenic pressures due to human activities such as nutrient overenrichment, climate change, marine litter and extensive fishing, which exert pressure on the environment, are evaluated based on their assessed overall impact on the ecosystem services according to current available knowledge. The overall impacts on the ecosystem services are assessed as small or unlikely negative, moderate negative or large negative. Significant knowledge gaps are highlighted wherever found appropriate. Ecosystem services classified as having bad status (Table i) are maintenance of foodwebs and provision of food (in all Swedish marine sub-regions), maintenance of habitats (in the Kattegat and Skagerrak as well as in the Baltic Proper), and provision of raw material (fodder fish in the Kattegat and Skagerrak). Several ecosystem services were assessed as having good status, e.g. energy provision, provision of genetic resources and cultural inspiration. A number of ecosystem services are, in addition, classified as having moderate status, e.g. natural heritage, recreation, and maintenance of biodiversity. In general, the Gulf of Bothnia has a somewhat better status regarding ecosystem services than the other marine sub-regions, which concurs with a lower level of anthropogenic impact on the marine environment. Comparing the Skagerrak and Kattegat to the Baltic Proper, the ecosystem service provision of raw material differs, with poor status in the Kattegat and Skagerrak and moderate status in the Baltic Proper. Apart from that, their overall patterns regarding status are similar. Among the anthropogenic pressures, nutrient overenrichment has a large negative net impact on maintenance of primary production and habitats. The increasing carbon content in the sea associated with climate change has a large negative net impact on biogeochemical cycles. Extensive fishing has a large negative net impact on maintenance of foodwebs and on provision of food.

This report represents the latest, most detailed and reliable assessment of nutrient loads from Swedish sources yet made. This report, together with its background reports, presents results, source data and calculations techniques with a level of detail intended to achieve full transparency and traceability as well as to permit further use of this work in Swedish water management. 

The Swedish Agency for Marine and Water Management gave SMED the task of evaluating sources of nitrogen- and phosphorus loads for the year 2014 and assessing the magnitude of those loads on lakes, water courses and the sea across Sweden. The aim was to produce the basis for Sweden’s national reporting to the Helcom ’Pollution Load Compilation 6 – PLC 6’ and to support water management work in Sweden. Similar calculations have been made previously but never with such high resolution in the input data. The work required processing and analysis of large amounts data to give complete information for the whole of Sweden, divided up into approximately 23 000 water bodies. 

This increased resolution, together with the improved quality of input data and newly developed calculation routines provide more reliable estimates of total loads even at the local scale. The development work that has been completed will form the basis of the next load assessment report, PLC 7, the indepth evaluation of the national environmental target ’Zero eutrophication’ and future work within marine and water management. 

The new calculations make use of new, high resolution land-use and soiltype maps, new data concerning purification in off-mains sewerage and storm water as well as a new height database (with 2 metres horizontal resolution). The height database has been used to calculate slope steepness, which is of great importance for estimates of phosphorus leakage. New observations in forest areas in southwestern Sweden have provided a better understanding of nutrient leakage in woodland areas and a new nutrient retention model has been developed as a result. These improved input data and high resolution calculation tools improve certainty in the results even at a local scale for individual water bodies. The results are made publically available through a new web tool, ’Technical Calculation System: Water’ (TBV, tbv.smhi.se).

The results are presented in terms of gross- and net loads. Gross loads are the amount of nutrients released at source to a water body or lake from for example a sewage treatment works or an agricultural field. Net loads are the proportion of the gross loads that reach the sea. Additionally, results are presented as anthropogenic and total loads. Anthropogenic loads come from human activities, such as crop production in agriculture or emissions from industry. Total loads are the sum of the anthropogenic loads and background loads, which are the natural loads which would occur even if people were not present. The boundary between what is background and what are anthropogenic loads is based on the Helcom definition where all soil use contributes with both a natural load and possibly also an anthropogenic load. For example loads from landuse covered with forest are considered background, while loads from a clearcut or agriculture are considered the sum of both anthropogenic and background loads. In results where only anthropogenic loads are presented, the background loads have been taken away.

Agricultural and forest land are the two largest sources of total loads to the sea for both nitrogen and phosphorus, with 34 100 and 34 900 tonnes of nitrogen and 1 100 and 850 tonnes of phosphorus, respectively during 2014. Together, these sources account for roughly 60% of the total load. For anthropogenic loads, agriculture is the largest source (23 300 tonnes nitrogen and 460 tonnes phosphorus), followed by emissions from sewage treatment works (14 000 tonnes of nitrogen and 240 tonnes of phosphorus). Loads from forest soils contribute only to the background loads while clear cuts, which a classed as an anthropogenic load contribute with only about 1500 tonnes of nitrogen and 20 tonnes of phosphorus. 

The Bothnian Sea, Baltic Proper and Kattegat are those sea areas which receive the most nitrogen from Sweden’s total loads (29 500 tonnes, 29 400 tonnes and 28 700 tonnes respectively, or approximately 25% each). In the Bothnian Sea however, the greater part of this load is ’natural’ background loads. The Baltic Proper and Kattegat receive the most anthropogenic nitrogen, 33% and 31% respectively.  For phosphorus, most goes to the Bothnian Sea (990 tonnes or 30% of the total load). Just under a quarter reaches the Baltic Proper (780 tonnes) and about a fifth reaches the Kattegat and the Bothnian Sea (680 and 630 tonnes respectively). 

The Baltic Sea Action Plan (BSAP) provides emissions targets, with the aim of achieving good environmental status in the Baltic Sea (including the Kattegat). According to this analysis, the target for phosphorus is achieved in all basins except the Baltic Proper, where the target is extremely challenging and it will be difficult to reduce the phosphorus loads under the load ceiling (308 tonnes).This requires substantial measures on the anthropogenic load, but further challenging, is that the background loads are a significant proportion of the total load. Total net phosphorus load to the Baltic Proper is 780 tonnes per year according to these calculations, of which 370 tonnes are background loads. This requires therefore that measures must even reduce the background load, for example through creation of wetlands. For even the Baltic  Proper to achieve good environmental status with regard to eutrophication, measures will be required in all sub-basins of the Baltic Sea.  Because of the major changes in methods and input data, it is not possible to directly compare how loads have changed since PLC 5 (based on 2006 data) or the in-depth analysis of the national environmental target ’Zero eutrophication’ (based on 2011 data). For example, the total area of agricultural land has fallen by 1900 km2 since 2006, which leads to a reduction in the estimated nutrient losses. The magnitude of this reduction cannot presently be read from the calculations as they have been made with higher resolution in data compared with earlier years. At the same time, the new calculations show that the anthropogenic part is lower than earlier calculated. Recalculation of the older PLC data with the new methods is necessary to clarify how much of the observed changes result from measures within farming and how much is due to the improved input data and calculations. Nutrient loads from point sources are calculated in the same way as before and for these it is clear that discharges have reduced. In PLC 6 (2014) sewage treatment works were responsible for 240 tonnes of phosphorus and 14 000 tonnes of nitrogen, while in PLC 5 (2006) loads were 350 tonnes of phosphorus and 17 000 tonnes of nitrogen (net). Industry have also reduced their impact and are responsible for 250 tonnes of phosphorus and 3 800 tonnes of nitrogen, compared with 320 tonnes phosphorus and 4 800 tonnes nitrogen in 2006.

The adoption of measures to protect and conserve the marine environment of the NorthEast Atlantic is a field in which the OSPAR Commission has been working for over thirty years. OSPAR measures in the form of Decisions and Recommendations for the protection of the marine environment have often acted as a forerunner of European Union environmental action. Substantial progress has been made in addressing discharges, emissions and losses of hazardous substances, nutrients and radioactive substances. While these fields still remain relevant, OSPAR’s work on measures has now moved on to focus on biological diversity.

Since 2011, the Swedish Agency for Marine and Water Management (SwAM) has been responsible for the coordination of Sweden’s work within the OSPAR Convention for the protection of the marine environment of the North-East Atlantic. SwAM is also responsible for the implementation of the EU Marine Strategy Framework Directive (MSFD) to achieve good environmental status in Sweden’s marine waters and for those national Environmental Quality Objectives most relevant to the aquatic environment.

This report examines and elaborates the contribution of the development and implementation of OSPAR measures to achieving good environmental status and moving towards Sweden’s environmental quality objectives. Following a general background on OSPAR, MSFD and Sweden’s system of environmental quality objectives, the development and history of OSPAR measures (decisions and recommendations) is described. The development of a methodology for evaluation of the implementation of OSPAR measures is presented. This methodology has then been used to guide an evaluation of the implementation of OSPAR measures in Sweden based on information report to OSPAR and available from national authorities. Finally a series of conclusions and recommendations are presented to guide future implementation work on OSPAR measures. It is clear that Sweden’s engagement in OSPAR has been of benefit in promoting marine environmental protection both in Sweden and other countries sharing the marine waters that surround Sweden. Overall, Sweden has a strong track record of engagement in OSPAR work and in fulfilling its commitments and obligations. The report does, however, highlight a small number of long-standing measures where implementation has not been completed either because the requirements of the measure have not been met or because a full implementation has not been demonstrated in the information reported even though it has occurred. For more the recently adopted biodiversity measures the implementation process is still underway. The evaluation highlights a number of steps that could be taken to secure this legacy through improved information recording and also points towards areas where an improved national implementation process could assist OSPAR work.

The report recommends that SwAM promotes that any future measures adopted by OSPAR have a more clearly described regional coordination role in the context of MSFD. This can help build synergy and reciprocity between the two processes with OSPAR offering a regional coordination mechanism to support MSFD objectives and the legal framework of the MSFD providing a means to underpin work towards OSPAR’s objectives. Alongside this efforts should continue to make use of OSPAR to pioneer new forms of action for which regional coordination would be of benefit (as has been the case in the past with hazardous substances and biodiversity, litter and noise), both within the context of MSFD and beyond. Increased recognition of the contribution of Sweden’s engagement in regional sea cooperation (including through OSPAR) to the system of environmental objectives would enhance understanding and profile of the regional sea work. An official description of how OSPAR and other regional sea work, such as through HELCOM, are seen to apply in areas where the convention areas overlap would help to guide work by other state authorities.

SwAM is recommended to continue Sweden’s positive record of engagement in OSPAR work by ensuring that the quality of information provided on the implementation of measures is sufficiently detailed to provide a fully auditable record of Sweden’s implementation of OSPAR measures. It is recommended that, for the avoidance of doubt, Swedish authorities reporting on implementation of OSPAR measures should always provide a national view on whether a measure has been fully implemented or whether work to implement the measure is still in progress.

Efforts to enhance the engagement of implementing bodies in work to implement OSPAR’s measures need to be nurtured and supported to build the engagement of other relevant national authorities, county administration boards and municipalities. It is suggested to consider an improved information recording on the national implementation process for OSPAR measures. This would benefit the implementation process for the more recently adopted biodiversity measures. There may be synergies that could be developed with existing information systems developed in other contexts, such as VISS (developed by the Water Authorities for Water Framework Directive measures) or Skötsel DOS (developed by SEPA for measures in protected areas). 

Within OSPAR, SwAM is invited to consider promoting approaches to develop a better shared understanding of how and when formal OSPAR decisions and recommendations should be developed which would help those Contracting Party delegates charged with the development of programmes and measures. SwAM is invited to propose that OSPAR work to develop its information systems includes the recording information on measures and their implementation. It is proposed that information on OSPAR measures compiled in spreadsheet form to support analysis in this project would provide a basis for a relational database on OSPAR measures. Building systems for reporting on implementation with improved content management by Contracting Parties would be beneficial to the OSPAR measures and actions programme (MAP). There may be benefits in coordinating this work with other Regional Sea Organisations. To support work according its commitment to apply an ecosystem approach OSPAR should also continue to develop its evaluation of the implementation of measures in close association with the development of its monitoring and assessment work. SwAM is invited to make use of the framework for the evaluation of the implementation of OSPAR measures developed in this project to support discussion in OSPAR on future implementation of measures and its link to the evaluation of the effectiveness of measures in OSPAR monitoring and assessment work.

Regeringen gav Havs- och vattenmyndigheten (HaV) i uppdrag att bidra till att stärka arbetet med utbildning för hållbar utveckling inom havs- och vattenfrågor, särskilt marin pedagogik. Uppdraget har genomförts av Havsmiljöinstitutet och forskare vid Göteborgs universitet som kontaktat lokala aktörer inom marin pedagogik, och inventerat deras behov av kunskapsmaterial och stöd.

Marin pedagogik är ett verktyg för att skapa förståelse för hur havet påverkar oss människor och för hur vi påverkar havet, vilket kallas för ocean literacy på engelska och som översätts till havsmedvetenhet i rapporten. En marinpedagogisk aktör förmedlar information om havet och/eller sambandet mellan vatten och hav, vilket i sin tur kan ge upphov till havsmedvetenhet om mottagaren tar ställning till informationen och sätter in den i ett förståeligt sammanhang.

Regeringsuppdraget avgränsades genom att inkludera aktörer vilka fokuserade helt eller delvis på havsvatten och som befinner sig utanför det obligatoriska skolväsendet.

Aktörerna lyfter fram behov av:

• finansiellt stöd (som bör vara långsiktigt)
• nätverk (mötestillfällen skapas)
• databas (för att dela med sig av marinpedagogiska resurser.

Aktörerna efterlyser kunskapsmaterial av olika slag, främst:

• skriftligt material/information (material anpassade för olika åldrar
• Digitala resurser (för att inspirera och engagera ungdomar)
• forskarkontakt (som behövs för metod- och faktakoll)

The purpose of this project is to provide a basis for assessing socio-economic values of achieving good environmental status in the North Sea and the Baltic Sea according to the Marine Strategy Framework Directive. A further purpose is to assess socio-economic values from Swedish commercial fishing as well as marine tourism and recreation in this context. In order to describe the degree of influence of the activities and the loads on the ecosystem services, the analysis uses a system of matrices that describe the interaction between loads per activity, indicators of environmental status and ecosystem services in order to better assess the overall impacts on the ecosystem services. 

An assessment of socio-economic values of commercial fishing is implemented for the scenario that good environmental status is reached in the Baltic Sea and the Skagerrak according the Marine Strategy Framework Directive. For good environmental status to be achieved in terms of cod stocks, catches should not exceed the fishing mortality consistent with achieving Maximum Sustainable Yield (FMSY) for those stocks in accordance with the ICES assessment. In order to estimate the value of achieving good environmental status we have used previous valuation studies conducted for cod in the North Sea as primaries in a benefit transfer. The annual increase in benefits with respect to cod stocks is assessed to lie within the range of 277 and 1.549 billion SEK per year. For the period 2016 - 2020, the overall increase in net present value lies within the range 1.4 - 8.9 billion SEK and for the period 2016-2050 within the range 3.5 - 19 billion SEK of achieving good environmental status. Under the new Common Fisheries Policy, we estimate that good environmental status with regard to Maximum Sustainable Yield (MSY) for the key species will be reached by 2050, and involves a continued reduction in the fishing fleet in Sweden. This will lead to a decrease in employment in the Swedish commercial fishing sector. On the other hand, the new common fisheries policy recommendations that small-scale fisheries receive larger shares of the quota will counteract a decrease in employment. Overall, we expect that the current employment in the fishing fleet in the beginning will decrease due to retirement over the next few years but that it eventually stabilizes and returns to current levels again. This is because the improved environmental status results in more even fishery efforts (fewer temporary closings) and an increased share of small-scale fisheries that are more labor intensive. 

The initial assessment by the Swedish Agency for Marine and Water Management 2012 showed that the marine tourism accounts for a significant share of the Swedish maritime economy, approximately 17% of net sales. This includes cruise traffic, boating, holiday homes, commercial housing, other residents and day trips to the coast. An assessment of socio-economic values is implemented for the scenario that good environmental status is reached according to the Marine Strategy Framework Directive with respect to marine tourism and recreation. The analysis builds on the initial assessment 2012 concerning the link between tourism activities and its dependence and impact on marine ecosystems services. Assessments are also made for other marine and land-based activities affecting the marine ecosystem services. A businessas-usual scenario was developed for the period up to 2020 and then 2050, which was then compared to good environmental status.  The analysis shows that the socio-economic values that can be expected in the sector marine tourism and recreation, in terms of present values for reaching and maintaining good environmental status, amount to about 90-100 billion SEK. The value consists of the benefits that are expected to arise as a result of industry growth and increased recreational values. This assessment is uncertain.

This paper is based on the results from a long-term zooplankton investigation in the Baltic proper in the years 1968—1972. Additional results, obtained by the authors in more recent investigations, have also been used in order to enrich the material with information not obtained in the principal investigation.

Seven standard plankton stations, covering seven sub-areas of the Baltic proper have been visited on average four to five times per year. All cruises have been made in connection with ordinary hydrographical expeditions which means that all zooplankton samples are accompanied by a complete list of hydrographical data.

The paper describes the zooplankton fauna of the Baltic proper which comprises about 40 regularly appearing species excluding the micro zooplankton. The main part of the fauna in respect of biomass and production consists, however, of only 10—12 species. The most important were the cnidarian Aurelia aurita. the rotifers Synchaeta spp., the cladocerans Bosmina coregoni maritima and Evadne nordmanni, the copepods Pseudocalanus minutas elongatus, Temora longicornis, Acartia bifilosa, A. longiremis and Centropages hamatus and the larvacean Fritillariaborealis.

Species of less importance were the larvae of Pleurobrachia pileus, the cladocerans Podon intermedius, P. leuckarti and Pleopsis polyphemodides (the latter is abundant in coastal areas), the copepods Eurytemora sp. and Oithona similis, the larvae of gastropod species, Mytilus edulis, Macoma baltica, Cardium glaucum. C.hauniense and My a arenaria, the chaetognath Sagitta elegans baltica and the larvacean Oikopleura dioica.

Occaisonal species were the cnidarians Sarsia tubulosa and Cyanea capillata, the rotifers Keratella quadrata quadrata, K. qu. platei, K. cruciformis eichwaldi and K.cochlearis recurvispina, the larvae of Pygospio elegans and Balanus improvisus, the copepods Calanus finmarchicus, Limnocalanus macrurus and Cyclops sp., the mysidaceans Mysis relicta and M. mixta, the amphipod Hyperia galba and the chaetognath Sagitta setosa.

All samples have been collected by vertical, fractionated hauls with a Nansennet. The mesh size was 0.160 mm in the years 1968—1971 and 0.090 mm in 1972. A correction of all results due to the poor filtering capacity of the Nansen net has been made. The additional results are mainly based on samples from the UNESCOWP 2 net.

All specimens have been analysed to species and the copepods also to developmental stages. The biomass has been calculated as the sum of all individual volumes.

The paper also describes the hydrography of the Baltic proper in general and presents the data for temperature, salinity and oxygen in the years 1968—1972.The relationship between the unique hydrography of the Baltic with its stable, brackish water contidions and the planktonfauna is discussed.

The regulating factors for the vertical and horizontal distribution of the fauna were found to be either temperature or salinity or a combination of these factors.

The seasonal variation in biomass values showed a rather good correlation with the temperature of the surface layer viz. the lowest biomass values (< 10 g m-2) were usually found in March—April, an increase started in May—June and a maximum (30—60 g m-2) was most often reached in August—September. There were great variations in biomass between the seven stations. The highest mean values (20—25 gm"2) were found in the southern and south-eastern parts of the Baltic proper and the lowest (12—13 gm-2) in the northern and south-western parts. Looking at the biomass values over the whole period of investigation, a remarkable stability has been found. There is no evidence of either increasing or decreasing trend.

The production of zooplankton has also been estimated. According to our calculations the production amounts to about 20 gC m-2 year-1 (380 g wwt) in the southern Baltic proper and 10 gC m-2 year-1 (190 g wwt) in the northern part.

The last part of the paper discusses the role of zooplankton in the energy flow of the whole pelagic ecosystem, i.e. from primary phytoplankton production to reproduction and recruitment of pelagic fishes.

För att uppnå god ekologisk status avseende övergödning i svenska sjöar och kustvatten räcker det i många fall inte att enbart minska belastningen av fosfor från externa källor såsom reningsverk, enskilda avlopp, jordbruk och industrier. Detta beror på att förhöjd internbelastning från sedimenten leder till att halterna av fosfor i vattnet hålls höga. För att minska dessa halter skulle även internbelastningen behöva åtgärdas.

Åtgärder mot internbelastning är inte en ersättning för åtgärder mot näringsläckage från land till vattenmiljön, eftersom den externa näringsbelastningen måste vara nere på en tillräckligt låg nivå för att en internbelastningsåtgärd ska bli långsiktigt effektiv. Även om en framgångsrik åtgärd mot internbelastning resulterar i att fosforhalterna temporärt minskar, kommer den externa belastningen avgöra övergödningssituationen i vattenförekomsten på lång sikt. Det kan alltså vara nödvändigt att genomföra åtgärder mot både den externa och den interna belastningen till en och samma sjö.

Denna utvärdering baseras på delar av den projektverksamhet som finansierats genom   havs-­ och vattenmiljöanslaget (HVM-­‐projekt) under åren 2007-­‐2012 samt Lokala   vattenvårdsprojekt (LOVA-­‐projekt) under åren 2009-­‐2012. I rapporten återfinns en redovisning av vilken typ av insatser och projekt som finansierats, en utvärdering av åtgärdsprojektens miljöeffekter, och kunskapsprojektens användning som underlag i förvaltning av havs‐ och vattenmiljöer. Projektens samhällsnytta har också undersökts. Vidare har vi analyserat myndigheternas hantering av Projektverksamheten.

Sett över hela perioden 2007-­‐2012 har tilldelade medel för de HVM-­‐projekt som ingått i utvärderingen motsvarat 30% åtgärdsinsatser och 62% kunskapsinsatser. Därtill har en  mindre del av medlen avsatts till informationsinsatser och projekt med anknytning till genomförandet av konventioner och EU-­‐direktiv. För året 2012 hade denna fördelning förskjutits och uppskattas ha motsvarat 53% åtgärdsinsatser och 41% kunskapsinsatser.  LOVA-­‐medlen har sedan dess inrättande fördelats motsvarande 60%  åtgärdsinsatser och 40% kunskapsinsatser.

De viktigaste slutsatserna är:

Insatser och projekt   

Projekten har analyserats i förhållande till de villkor som anges för anslaget och den förordning som reglerar LOVA-­‐bidrag.

För HVM-­‐projekt har mest medel tilldelats ämnesområdena biologisk mångfald, övergödning  och miljöfarliga ämnen. Detta motsvarar de utpekat största miljöproblemen för svensk havs-­‐ och vattenmiljö. De åtgärdsprojekt som genomförts har fokuserat på restaurering av levnadsmiljöer och att minska utsläpp av kväve och fosfor. Denna typ av åtgärder framhålls som angelägna i  såväl svenska som internationella miljömål. Fördelning av medel på olika ämnesområden och  projekttyper förefaller således välgrundad och balanserad. Dokumentation som underbygger de  prioriteringar eller övervägande som gjorts är dock bristfällig.

LOVA-­‐bidrag ska enligt förordningen främst riktas mot projekt  som syftar till att minska övergödning vilket också har varit fallet. Enligt förordningen ska stöd ges till  ”genomförande av kostnadseffektiva åtgärder”. Utvärderingen visar att olika länsstyrelser har prioriterat olika projekttyper. Vi har inte haft tillgång till dokumentation som motiverar skilda prioriteringar eller som gör det möjligt att utvärdera åtgärdernas kostnadseffektivitet.

För att öka transparensen rekommenderar vi att myndigheterna  förbättrar dokumentation av övervägande och analyser som leder fram till prioritering av ämnesområden och val av projekt. 

Åtgärdsprojektens miljöeffekter   

Utvärderingen av miljöeffekter baseras på projektägarnas slutrapporter. Få slutrapporterade  åtgärdsprojekt anger miljöeffekter baserat på mätning före och efter genomförd åtgärd. Detta  gäller både HVM- och  LOVA-­‐projekt. Det är därför inte möjligt att  ange  projektens miljöeffekter annat än i enstaka fall eller baserat på beräkningar av förväntade effekter.

Brist på uppmätta miljöeffekter beror ofta på att effekterna inte kan klarläggas förrän flera år efter att projekten avslutats. Det är alltså i  många fall  för tidigt att utvärdera effekten av  åtgärder.                                                                                               

I de slutrapporter vi tagit del av anges planer för uppföljning av åtgärdsprojekt i ungefär hälften  av fallen. För dem som anger planer för uppföljning är det dock oklart hur finansiering ska ske efter avslutat projekt liksom hur och till vem som framtida uppföljning ska rapporteras.

Vi rekommenderar därför en stärkt uppföljning av åtgärdsprojekten. Alla projekt behöver inte följas upp genom mätprogram men den typ av åtgärder  som är önskvärda att utvärdera bör identifieras. Projekt som innefattar sådana åtgärder bör redan vid projektstarten garanteras medel för uppföljning. Vi ser också behov av stöd i planering av uppföljning, t.ex. i design av mätprogram. Om man önskar utvärdera miljöeffekter måst också högre krav ställas på  innehåll  i slutrapporter, till exempel redovisning av metoder och beräkningar. De miljöeffekter som anges i projektens slutrapporter måste också kvalitetssäkras.

Information om åtgärdsprojekt som genomförts, planeras eller pågår behöver också samlas  och tillgängliggöras för användning i nationell, regional och lokal åtgärdsplanering.

Kunskapsprojektens användning

Resultat från kunskapsprojekten förefaller väl använda t.ex. för att uppfylla miljödirektiv, som  underlag för myndighetsutövning, för utveckling av övervakningsprogram med mera. Slutsatsen  baseras på ett frågeformulär som riktats till projektägare av HVM-­‐projekt samt intervjuer med  myndigheternas handläggare.     

Kännedom om projektresultat förefaller dock vara starkt personknutet, detta gäller både HVM-­‐och LOVA-­‐projekt, och resultaten skulle sannolikt kunna användas i större utsträckning om de  är kända för fler. För närvarande finns risk att resultat och kunskap förloras.

Vi har haft tillgång till slutrapporter för 49% av de bidragsfinansierade HVM-projekten och  fullständig redovisning  från 46% av slutrapporterade LOVA-­‐projekt. Därtill initierar havs-­ och  vattenmyndigheten projekt i form av uppdrag och överenskommelser för vilka vi haft begränsad tillgång  till resultat. En stor del av både kunskaps-­ och åtgärdsprojekt som genomförts har alltså inte ingått i utvärderingen.

Vi rekommenderar att satsa på insamling och spridning av resultat. Dels bör det genomföras en insats för att samla alla slutrapporter eller annan redovisning från projekt som finansierats av anslaget. Vi föreslår även praktiska lösningar som att upprätta en databas över genomförda HVM-­ och LOVA projekt. Katalogisering av existerande rapporter, även sådana som producerats efter projektens avslut, och seminarier riktade mot potentiella brukare är andra förhållandevis enkla medel för att öka kännedom om resultaten.

Viktigt är också att samla erfarenheter och rekommendationer från projektägare av  genomförda projekt, detta gäller både åtgärds-­ och kunskapsprojekt.   

Projektens samhällsnytta   

I utvärderingen har vi på önskemål från Havs-­ och vattenmyndigheten undersökt de genomförda projektens samhällsnytta d.v.s. den nytta som ligger utanför projektens omedelbara miljöeffekter. Undersökningen om samhällsnytta är baserad på information i projektägarnas  slutrapporter, intervjuer med myndigheternas handläggare, och ett antal  fördjupade  studier.

På ett övergripande plan kan flertalet projekt kopplas till någon form av processrelaterad samhällsnytta, t.ex. kompetensutveckling hos deltagande individer och institutioner,  förstärkning av olika samverkansformer och produktion av  underlag för miljöförvaltning och politiska beslut. Vad gäller resultatrelaterad samhällsnytta, t.ex. förhöjda rekreationsvärden  eller ökad livsmedelsförsörjning, ges dock få exempel vilket sannolikt beror på att även projektens direkta miljöeffekter sällan är kända. Om samhällsnytta i framtiden ska utvärderas jämte projektens övriga effekter bör kriterier för samhällsnytta anpassas till olika projekttyper och indikatorer behöver utvecklas.  

Myndigheternas hantering av projekt

Hantering av projektverksamheten har analyserats baserat på dokumenterat material och  intervjuer med myndigheternas handläggare och utredare. Dokumentationen är bristfällig. Detta gäller både Naturvårdsverkets  och Havs-­ och vattenmyndighetens administration av havs-­ och vattenmiljöanslaget liksom länsstyrelsernas administration   av LOVA-­‐projekt. Rutiner för flera delar av hanteringen bör stärkas.

Vi rekommenderar att en plan upprättas för vad som ska uppnås med havs-­ och  vattenmiljöanslaget. Planen förhåller sig förslagsvis till de mål och åtgärdsprogram för  havs-­  och vattenmiljön som redan existerar och på en analys av vad som är rimligt att uppnå med  utgångspunkt från anslagets storlek. Gemensamma riktlinjer för granskning av projektansökningar och godkännande av slutrapporter behöver vidareutvecklas.

Övergripande slutsatser   

Trots brist på faktiskt uppmätta miljöeffekter har vi valt att resonera kring projektens potentiella bidrag till att uppnå några av de miljömål som Sverige eftersträvar, till exempel de reduktionsmål för utsläpp av kväve och fosfor som överenskommits enligt Aktionsplanen för Östersjön. De genomförda HVM-­‐projekten har uppskattningsvis endast bidragit till att minska utsläpp av fosfor och kväve med några promille av reduktionsmålen. Detta beror i stor utsträckning på projektens inriktning mot åtgärder som kräver medverkan av markägare, t.ex.anläggning av våtmarker eller införandet av   nya metoder i jordbruket. De projekt som hittills genomförts har inte lyckats få med sig  tillräckligt många deltagare för att på frivillig basis åstadkomma signifikant minskade utsläpp av näringsämnen. Innan liknande projekt fortsättningsvis finansieras bör projektägarnas erfarenheter samlas och de juridiska  förutsättningarna för att genomföra denna typ av åtgärdsprojekt bör utredas.

De uppgifter om reducerat utsläpp av näringsämnen som anges för LOVA-­‐projekt behöver  kvalitetssäkras. Redan den  begränsade granskning som  genomförts i denna utvärdering visar på  flera orimliga uppgifter. Baserat på en grov uppskattning beräknas dock genomförda LOVA-­‐åtgärder motsvara ett reducerat fosforutsläpp på cirka 30 ton fosfor per år d.v.s. motsvarande knappt 6% av de nyligen uppdaterade svenska reduktionsmålen för fosfor. Enligt de förväntade  miljöeffekter som anges av projektägare ligger dock de stora potentiella minskningarna av utsläpp i genomförandet av kommunala VA-­‐planer som framtagits med LOVA-­‐bidrag. Siffrorna  behöver dock granskas, utförbarheten av VA-­‐planerna (t.ex. avseende finansiering) är oklar, och  ett eventuellt realiserande av dessa planer ligger minst 5-­‐15 år framåt i tiden.

Fördelningen av medel från anslaget, framförallt HVM-­‐projekt, har under den utvärderade  perioden skiftat tyngdpunkt från kunskapsinsatser till åtgärdsinsatser. Vi vill understryka  koppling mellan och behovet av olika insatstyper;

- många åtgärdsprojekt kan inte genomföras utan föregående kunskapsprojekt, t.ex.  kartläggning och förstudier,

- det finns fortfarande kunskapsbehov för att genomföra åtgärder, bland annat utvärdering av olika åtgärders effekter liksom att bedöma var i landet som behoven av åtgärder är störst,

- resultat av kunskapsprojekten fyller många förvaltningsbehov,

- informationsinsatser med tydlig inriktning mot att ge underlag för ändrat beteende  kan  bidra till att långsiktigt förbättra tillståndet i miljön.

Vi rekommenderar därför en fortsatt finansiering av alla dessa insatstyper. Sammanfattningsvis har vi tagit del av många väl genomförda projekt vars  resultat  förefaller väl  använda inom havs-­ och vattenförvaltningen. Vi har också tagit del a projekt som långt från nått de mål som satts upp för projekten, ofta på grund av ogynnsamma förutsättningar för genomförandet. Otillräckliga krav på projektägare påverkar också möjligheten att utvärdera projekten. Med tydligare mål, uppföljning av   projekt, och spridning  av resultat kan havs-­‐ och  vattenmiljöanslaget nyttjas mer effektivt.

Eelgrass beds constitute key habitats in shallow, coastal areas that support high species diversity and provide mankind with several important ecosystem services. Eelgrass habitats have been identified as essential habitats in need of protection by international conventions and EU-directives. Along the Swedish northwest coast, more than 60 %, approximately 12 500 ha, of the eelgrass beds have vanished since the 1980's as a result of coastal eutrophication and overfishing. Although measures have reduced nutrient pollution and overfishing, and the water quality along the Swedish west coast has improved, no general recovery of eelgrass has been observed. Instead, the loss of eelgrass continues, partly due to an increasing exploitation of Swedish coasts. 

The aim of this report is to contribute to the development of an improved management of eelgrass ecosystems in Sweden, in particular regarding the use of eelgrass restoration, but also in relation to licencing and supervision of activities that can affect eelgrass and other coastal habitats. The goal has been to assemble all relevant information in one report, and provide a multidisciplinary background that address ecological, legal and economic aspects of management and restoration of eelgrass in Sweden. Another objective has been to analyze the existing management of eelgrass in Sweden, identify possible shortcomings, and provide recommendations on how it could be improved. The report constitutes an important basis for the handbook for eelgrass restoration in Sweden (Moksnes et al. 2016).

Although functional methods and guidelines for eelgrass restoration are now available for Swedish waters, it is important to point out that restoration of eelgrass is very labor intensive, expensive and not possible in all areas. When a large eelgrass bed is lost, the physical and biological environment may change so much that eelgrass can no longer grow in the area. It is therefore critical that environmental managers prioritize the protection and conservation of remaining eelgrass habitats, and restore lost meadows when possible, but only as a last resort use compensatory restoration of eelgrass as a measure to mitigate losses caused by coastal exploitation.

Eelgrass meadows create several important ecosystem functions, which in turn provide society with important ecosystem goods and services. A bioeconomic  analysis of three of these services (production of commercial fish and uptake and storage of carbon and nitrogen), estimates their economic value up to approximately 0.5 million SEK per hectare of eelgrass along the Swedish northwest coast. It is important to note that this value did not include several other important ecosystem services (e.g. increasing biodiversity, stabilization of sediment and prevention of beach erosion). The historical losses of eelgrass along the Swedish northwest coast were estimated to have caused a total loss of approximately 8000 tons in cod catches, which is equivalent to the total catch of cod in Swedish waters in 2013. The historic loss of eelgrass was also estimated to have caused a release of 6000 tons of sequestered nitrogen to coastal waters, which is three times larger than the annual river supply to the Swedish northwest coast. A rough estimate of the total economic value of the lost ecosystem services since 1990, including  carbon sequestration varies between 4 and 21 billion SEK.

There is no Swedish legislation that protects eelgrass meadows specifically, but a large number of laws and regulations that aim to prevent deterioration or restore deteriorated environments, or regulate what type of influence is allowed in different areas. However, the fact that exploitation of eelgrass is allowed also in areas where large historical losses have occurred, as well as within marine protected areas, demonstrates that the existing legal protection is insufficient. The situation is not in agreement with the EU water framework directive and the marine strategy framework directive to obtain and maintain good ecological and environmental status, and makes it difficult for Sweden to fulfill international commitments. 

The present management of eelgrass in Sweden is impeded by a lack of environmental monitoring and use of eelgrass when assessing the environmental status according to the EU directives. It is therefore important to revise the present indicator for coastal vegetation in Sweden, and to include the distribution of eelgrass in the national monitoring program so that the condition of the eelgrass ecosystems contributes to the classification of the environmental status. Together with a no-net-loss policy, such a change would increase the protection of eelgrass substantially and also clarify the need to carry out large-scale restoration of lost eelgrass meadows.  Compensatory mitigation has been used very little in the marine environment in Sweden, and no compensatory restoration of eelgrass has yet been carried out.

Compensatory restoration could constitute a tool to implement the "polluter pays principle", and contribute to prevent net-losses off eelgrass habitats caused by coastal exploitation. In contrast to the present use of economic-fees to compensate the fishery when an eelgrass bed is damaged, all ecosystem services would be compensated for after a successful compensatory restoration. However, compensatory mitigation is not unproblematic and it is critical that the compensation does not affect the permission process, but that it is only used as a last resort after all possibilities to avoid and minimize the damage have been exhausted. This is particularly important in the southern part of the Swedish northwest coast where studies have shown that there are areas where restoration is not possible. Moreover, due to the large historic losses of eelgrass in this region, most areas where compensatory restoration could be attempted consist of bottoms where eelgrass was growing in the 1980's. Restoration in those areas would only compensate for the historic losses, but not for the eelgrass harmed by exploitation, resulting in a net loss of habitat.

In Swedish legislation there are several alternative sections of law that could be used to demand compensatory mitigation when eelgrass is affected negatively by an activity. The best support for demanding full compensation is in the Swedish environmental code (miljöbalk) chapter 16, section 9. Until recently, the lack of established practice has constituted a challenge to demand compensatory mitigation in the marine environment. However, this is about to change as land- and environmental courts have started to demand of compensation. It is recommended to increase the use of "biotope-protected areas" for eelgrass habitats as this protection would increase the possibility to demand compensatory mitigation for eelgrass, and more importantly, put higher demand to avoid and minimize damage on eelgrass habitats. 

Experience from the USA, where compensatory restoration of eelgrass has been used as a management tool since the 1970's, has shown the value of developing state wide policies regarding what methods that should be used during restoration, how the extent of the restoration should be calculated, and how the success of the restoration should be determined. A national eelgrass mitigation policy would facilitate the use and the chances of success for compensatory restoration in Sweden, and this report presents a detailed description of how such a policy could be designed.

More than 60 % of the eelgrass has vanished from the Swedish northwest coast since the 1980s as a result of nutrient pollution and overfishing. Although measures have improved the water quality significantly in recent years, no  natural recovery of eelgrass has occurred. Instead the losses of eelgrass continue as a result of e.g. coastal exploitation. Restoration of eelgrass constitutes a potential tool to recreate historic habitats and to mitigate eelgrass meadows that are destroyed during exploitation.

This handbook provides detailed technical guidelines for eelgrass restoration in Scandinavian waters and includes all important steps in the restoration  process, from site selection and permit processes to harvest and planting of eelgrass, and monitoring and evaluation of results. The described methods are based on extensive studies carried along the northwest coast of Sweden, from 2010 to 2015, and are mainly applicable for the Skagerrak–Kattegat area including the Sound. Some of the methods may also be appropriate for the  southern part of the Baltic Sea, but complementary studies will be needed before they could be recommended also for this area. 

Although functional methods for eelgrass restoration now are available for Swedish waters it is important to note the eelgrass restoration is very labor intensive, expensive and the results are many times uncertain. When an eelgrass meadow is lost, the physical and biological environment may change so much that it no longer allows eelgrass to grow in the area. It is therefore not always possible to restore a lost eelgrass bed. Hence, it is imperative that environmental managers prioritize the protection and conservation of remaining eelgrass habitats, and only as a last option use compensatory restoration as a measure to mitigate losses caused by coastal exploitation. 

A critical first step, before large-scale restoration is initiated, is to evaluate if the existing environmental conditions at potential restoration sites allow eelgrass to grow. Monitoring of physical and biological conditions and testplanting of eelgrass should therefore be carried out for at least 12 months prior to selecting a restoration site. The dominant causes to why eelgrass plantings fail along the Swedish northwest coast are poor water quality resulting from local sediment resuspension, disturbance from bottom-drifting perennial algal mats and shore crabs, and shading from ephemeral algae. In general it is recommended that eelgrass restoration should only be attempted at sites where the light availability at the planting depth is at least 25 % of the surface  irradiance, and where test-planted shoots show positive growth after one year. 

Before any restoration work is started it is important to contact relevant local authorities to obtain information regarding necessary permits and required communication with stakeholders. For the methods recommended in this handbook, only a consultation with the County Administrative Board is normally required. For eelgrass restoration in Sweden, the single-shoot method is recommended where single, adult shoots are harvested and planted by hand, without sediment from the donor meadow, using diving. To decrease winter mortality resulting from ice-scouring or insufficient light, it is generally recommended that shoots are planted in the beginning of June, between 1.5 and 2.5 m depth. It is also recommended that shoots are planted 0.25 to 0.50 m apart (equivalent to a planting density of 4 to 16 shoots per kvadratmeter) and that the size of the planted area is at least 1000 m2 to increase the chances of positive feedback mechanisms from the restored meadow. The recommended methods for harvest do not result in any measurable impact on the donor meadows, and the planting methods are relatively fast. Studies suggest that 4 divers could harvest and plant 40 000 shoot covering one hectare in 10 working days. During optimal conditions the shoot density can increase 10 times before the winter. Since the harvest and planting is done by hand, the method will likely limit the size of possible restoration projects to less than 10 hectares per year, which is a very small amount in comparison with the 1000s of hectars that has been lost along the Swedish west coast since the 1980s. Thus, the available restoration methods can likely not alone recreate the historic distribution of eelgrass. However, in combination with large-scale measures that improves the conditions for eelgrass growth along the Swedish west coast, restoration at strategically chosen locations may constitute an important complement that could enable and accelerate natural recovery of Swedish eelgrass habitats.

Monitoring of the restored eelgrass bed is critical to evaluate if the goals of the restoration are met, and must be part of every restoration project. This is particularly important in mitigation projects to ensure that no net-loss of eelgrass occur. This handbook recommend that the result of the restoration is primarily evaluated by comparing eelgrass shoot density, biomass and areal extent of the planted bed with the same variables in a natural, reference bed over a period of 10 years. The total cost of restoring one hectare of eelgrass using the recommended methods is estimated to vary between 1.2 and 2.5 million SEK. These values include the cost of site selection for one year and monitoring for 10 years (0.38 and 0.39 million SEK, respectively), which are independent of the size of the restoration project. The cost of harvesting and planting, on the other hand, is directly proportional to the size of the planted meadow, and the shoot density used, and varies between 0.44 and 1.73 million SEK per hectare for the  recommended methods. If anchoring techniques need to be used the planting cost could double. Thus, it is important to identify optimal planting methods during evaluation of restoration sites to keep the costs down. Methods for eelgrass restoration using seeds have also been developed for Swedish conditions. However, seed methods cannot presently be recommended due to very high and variable losses of seeds, and high costs. In comparison with the single-shoot method, seed methods have higher risks of failure, take two additional years to obtain a functional eelgrass meadow, and are estimated to cost two to three times more with available methods.

This is an action plan to protect eelgrass beds (Zostera marina och Z. noltii) in Sweden. The action plan is intended as a guideline and contains proposals for measures that should be implemented in the period 2017–2021. The long-term goal with the plan is to safeguard the ecosystem functions of eelgrass beds to the coastal systems by increasing the protection from exploitation, improve the environmental conditions for eelgrass growth, and facilitate natural recovery of eelgrass by restoration and other measures. The vision is that eelgrass beds will recover their historical depth distribution and areal extent all over Sweden, and provide nature and mankind with their ecosystem functions and services.  

Eelgrass beds constitute key habitats in shallow, coastal areas that support high species diversity and provide mankind with several important ecosystem services. Eelgrass meadows constitute nursery habitats for a number of commercially important species including Atlantic cod, whiting and eel. Eelgrass also improve water clarity by stabilizing the bottom and decreasing sediment resuspension, and they mitigate eutrophication and climate change by sequestering and storing nutrients and carbon in the sediment. Eelgrass meadows have been identified as essential habitats in need of protection by international conventions and EU-directives.   

Eelgrass beds are threatened ecosystems and their distribution has decreased rapidly in the northern hemisphere the last century. In Scandinavian waters the depth distribution of eelgrass has decreased 50% since the 1900s as a result of eutrophication and decreased water quality.  Along the Swedish northwest coast, more than 60 %, approximately 12 500 ha, of the eelgrass beds have vanished since the 1980's as a result of coastal eutrophication and overfishing. Although measures have been taken, and the water quality has improved, no general recovery of eelgrass has been observed. Instead, the loss of eelgrass continues, partly due to an increasing exploitation of Swedish coasts.  To stop the ongoing losses, and facilitate a recovery of eelgrass in Sweden, the following actions are suggested:  

Map the present distribution of eelgrass in Sweden 

• Include areal extent and depth distribution of eelgrass in national and regional marine environmental monitoring. 
• Improve the environmental conditions for eelgrass growth by intensifying measures to reduce nutrient pollution to the sea, and to increase the population of large predatory fish in the coastal zone, and by decreasing activities that can deteriorate the water quality close to eelgrass habitats, such as dredging, dumping of dredging material, boat traffic, etc. 
• Improve the protection for eelgrass from coastal exploitation by revising existing nature protection and implementing new marine protected areas that include eelgrass, take into account the cumulative effect of small scale exploitation when evaluating permits, and by increasing supervision of legal and illegal water activities along the coast. 
• Restore lost eelgrass meadows in areas where this is possible to facilitate natural recovery of eelgrass. Use also eelgrass restoration as compensatory measure for eelgrass lost due to exploitation, but only as a last resort after demands of avoiding and minimizing damage of the habitat. 
• Inform the public and decision makers, and educate personnel at environmental courts, managers handling exploitation permits, etc. about the ecological significance of eelgrass beds, their sensitivity to disturbance, and what can be done to decrease the human impact.   
• Improve the knowledge of how climate change, runoff from land, dumping of dredge material, boat traffic, etc., may impact eelgrass ecosystems in Sweden, and develop new methods and measures that can improve the local environment for eelgrass growth and recovery.  

This action plan has an estimated total cost of 82 million SEK during the actions plans' validity period 2017-2021.

The Marine Environmental Ordinance (SFS 2010:1341) is part of a strategy to bring about ecosystem-based management and sustainable use of the marine environment in accordance with the EU’s the Marine Strategy Framework Directive (MSFD, 2008/56/EC). The ordinance is intended to maintain or achieve good environmental status in the marine environment. Under the Marine Environmental Ordinance, the Swedish Agency for Marine and Water Management (SwAM) must ensure that an initial assessment is carried out on the marine environment in the Swedish waters of the two regions, the North Sea and the Baltic Sea (Articles 13–16). The initial assessment, which is to be completed by 15 July 2012 and reported to the European Commission not later than 15 October of the same year, is to provide a basis for the establishment of good environmental status, environmental targets and environmental monitoring programmes, as well as the preparing of programmes of measures by which established targets may be achieved.  The initial assessment will include conducting an economic and social analysis. The former can be divided into two parts, the first of which is designed to analyse the use of the marine region and the second to describe the cost of the degradation of the marine environment (Marine Environmental Ordinance, Article 13, para. 4, and the Marine Strategy Framework Directive, Article 8.1c).  The primary purpose of the social analysis in the initial assessment is to create a picture of the underlying conditions of the upcoming work to achieve the aims of the directive, that is, good environmental status (GES, Article 9). The analysis is also intended to provide basic information for the establishment of environmental targets (Article 10) that will subsequently form the foundation of programmes of measures and administrative funding (Article 13). The assessment includes an analysis of how different groups in society can be affected by how the sea is used and by marine environmental problems and measures taken to address them. This study presents a method by which such an analysis can be conducted. The method includes a conceptual model that consists of the components 'Indirect driving forces, 'Direct driving forces , 'Environmental pressures, state  and impact', 'Impact on society', and 'Response'. The model is used in combination with a question template to analyse actors, activities and driving forces. Case studies involving three environmental problems – selective overfishing of cod and the unwanted dispersion of mercury and phosphorous – show that a large number of actors are involved, directly and indirectly. In addition, these actors operate on several levels –local/regional, national and international.  Every environmental problem requires its own analysis and has its own set of conditions. The study shows that the information needed for making decisions regarding the measures that should be taken is relatively extensive. The determination of the amount of information necessary and therefore how much should be systematically collected in future can have a great impact on the development of society and the environment. Finally, suggestions are given as to how future social analyses relating to the marine environment might be carried out.

The initial assessment (IA) of the implementation of the EU Marine Strategy Framework Directive (MSFD) includes an economic and social analysis (ESA). This analysis covers two components: (1) the use of marine waters and (2) the cost of degradation of the marine environment. The Swedish ESA work has entailed four different areas, reported in four separate reports:  A. The maritime sector (IVL and Enveco, 2012  "Report A") B. Marine tourism and recreation (Enveco, DHI and Resurs, 2012  "Report B") C. Oil spill (IVL, Enveco and EnviroEconomics Sweden, 2012  "Report C") D. Marine litter (Enveco and DHI, 2012  "Report D") The purpose of this analysis is to synthesize the results of the four reports.  The Swedish ESA is based on the ecosystem service approach and also on the DPSIR framework for sorting out relationships between Drivers, Pressures, State, Impact and Response. The point of departure in terms of marine ecosystem services is the classification in Table 0.1. We apply an ecosystem service analysis that in principle follows the procedure of a Corporate Ecosystem Services Review (ESR) (WRI, 2008) for evaluating a human activity’s dependence of – and impact on – eco system services. In the DPSIR context, the focus is on both how a driver influences the status of ecosystem services through its pressure and how the driver is affected by the status of ecosystem services. In short, this analysis applies the following four steps:  I. Identify the human activities, i.e. the drivers.   II. Identify associated pressure (for each driver) and determine (1) which ecosystem service(s) it is mainly dependent upon and (2) which ecosystem services it mainly affects. Based on this "filter", select the most relevant ecosystem services for further analysis.  III. Analyze the status and trends in the selected ecosystem services by associating them to Good Environmental Status (GES) descriptors and indicators.  IV. Analyze how a business-as-usual (BAU) scenario influences the trend in GES indicators and thus, the implied status of ecosystem services.

Large parts of the Baltic Sea and the Kattegat and Skagerrak suffer from eutrophication. Historically, this is due to due to an excessive input of nitrogen and phosphorus to the sea. In the present report, we focus on some of the root causes of this input and how changes in society can reduce the eutrophication pressure on marine environments. Four societal phenomena were selected for a closer analysis. Three of these phenomena - protein consumption, unnecessary food waste, and phosphorus additives in food - are related to the impact of food consumption on the sea. Horse keeping was also considered to be a relevant case study, as the number of horses in Sweden is growing rapidly

Assessing how changes in societal phenomena can influence the physical flow of nutrients into the sea is a complex task. The number of factors that can modify the final result is very large, and one type of changes in society is normally accompanied by a set of other changes. For example, changes in the consumption of food will inevitably have implications for land use. Moreover, many of the actors that influence the flow of substances and products through society operate on a market where the current activities are continuously modified or substituted by others.

In this report we tried to handle the complexity of the problems addressed by making simplifying assumptions. For example, we assumed that changes in food consumption will be identical or similar for Swedish produced and imported products and that agricultural land not any longer needed for food production will obtain a leaching coefficient corresponding to a theoretically derived background level. Keeping in mind that the load reductions presented here are maximum load reductions based on a number of assumptions our study allowed the following conclusions:

o A lower intake of protein-rich food products (25% less protein) could imply that, each year, about 200 tonnes less phosphorus and nearly 9.000 tonnes less nitrogen would reach the sea. Dietary changes can reduce the land area needed to ensure an adequate food supply but also lower the households’ burden on municipal and on-site sewage systems. Replacing some animal protein with legumes can help to reduce the input of nutrients into the sea, but it is more important to reduce the total intake of protein-rich food.

o If phosphorus compounds added to various food products are substituted or eliminated, the annual input of phosphorus to the sea could be reduced by about 60 tonnes per year. This amount is of the same order of magnitude as the effect of the already implemented ban of phosphate in dishwasher detergents.

o Reducing the amount of unnecessary food waste is both desirable and feasible, and smaller amounts of waste imply that less land is needed for food production. However, the load reductions of 6 tonnes of phosphorus and 450 tonnes of nitrogen are relatively small compared to the effect of dietary changes.

o Horse keeping is a growing sector and source of nutrient emissions. Moreover, paddocks can locally cause relatively large emissions of nutrients. However, horse keeping cannot be regarded as a major driver of eutrophication because the leaching of nutrients from this form of land use is lower than the average for all agricultural land in Sweden. The potential load reductions are substantial compared to the remaining Swedish reduction targets in the Baltic Sea Action Plan. Altogether, the results of the present study suggest an increased emphasis on what and how much protein-rich food consumers eat and on the use of phosphorus additives in the food industry.

The present report gives the status of fishpopulations in inland waters and coastal rivers in Sweden. The stock data consist of electrofishing results, fish ladder counts, fishing statistics and stockings from rivers. From the four greatest lakes data consist of fisherystatistics, prey species abundances (hydroacoustics) and stockings.

Anadromous salmon and trout on the Swedish west coast depend on liming. Salmon sea survival has declined. Added to these problems are increased occurrence of the parasite Gyrodactylus salaris and Danish experiments with delayed release of salmon in the southern Baltic. The latter has lead to increased contamination of natural spawningstocks with stocked salmon. The fishing on mixed salmon stocks must cease to improvethe number of spawners, especially in small populations. Brown trout stocks are stable.

Due to overexploitation by the sea and coastal fishery, natural anadromous salmonin the Baltic were below acceptable levels,with increasing risk of genetic deteriorationand considerable economic losses. Due to reduced TAC (total allowable catch) and reduced effects of the M74 syndrome, causing excessive fry mortality, stocks are slowly increasing. The situation for anadromous browntrout in the Baltic is unclear, but several small stocks are too heavily exploited by gillnetting close to river mouths.

Lake resident salmon occur naturally only in Lake Vänern, where the two remaining stocks have suffered heavily from the building of dams for hydroelectric purposes.The fishing is based on stocked fish, all without the adipose fin, while the few natural produced fish, i.e. with adipose fin left, are protected. Increased legal size together within creased closed areas are measures that have improved the conditions for the stocks in the last years, but both stocks must still be regarded as threatened.

Trout populations in inland waters have generally increased during the last two decades. Liming, habitat restoration and increased closed areas are considered the most important measures for the stocks in the future.

Approximately 200 commercial fishermen utilize the four great lakes (Vänern, Vättern, Mälaren, Hjälmaren). Detailed fishery statistics are collected on a monthly basis, including effort. In Lake Vänern salmon (’lax’) and trout (’öring’) together with whitefish (’sik’) and cisco (’siklöja’) dominate the catch. Roe from cisco contributes with approximately 50% of the catch value, but the population is presently declining. In Lake Vättern the catch is dominated by salmon, Arctic char (’röding’) and whitefish. Stocking of salmon, a new species in the lake, gives a high yield; 600-800 kg salmon/1,000 smolts released. Monitoring is carried out to study if the salmon stockings will have negative effects on the resident Arctic char, as the two species compete for the same prey species. In both lakes trolling for salmon and trout takes a large part of the total catch. In Lake Mälaren and Hjälmaren eel (’ål’) and zander (pikeperch, ’gös’) are important species. The eelfishery is completely dependent on stockings. In the former lake cisco was important until late 80’s, but then the population drastically declined, due to recruitment failure. The reason is not clear, but it coincides with warm winters with a short period with ice cover.

The status of the crayfish (Astacus astacus) is given in chapter 7. The crayfish plague was spread from Finland to Sweden in 1907 and many populations of the native crayfish have been eradicated. The plague later was further spread due to introduction of the American crayfish (Pacifastacus leniusculus).Today Astacus astacus is considered an endangered species in southern Sweden, and restriction on stockings of the American crayfish has been imposed. Due to the membership in EU the threat to the native species has increased as import of live exotic crayfish species has been allowed.

A drastic decline of the immigration of young eels have been noted in Swedish coastal rivers. This has lead to decreased Swedish catches in the Baltic, while the catches on the west coast have remained unchanged.

Fishery management must be carried out in such a way that biodiversity will not deteriorate. In chapter 9 biodiversity in stream populations is studied with the use of electrofishing data. Negative effects on biodiversity were mainly found in acidified waters and waters with extensive hydroelectric power development. It was concluded that biodiversity in general had remained unchanged or improved slightly during the last two decades, much thanks to liming and fishery management. A programme for monitoring of the biodiversity in the four great lakes has recently started, and preliminary results suggests that some non-commercial species need specific attention, e.g. river lamprey and Aspius aspius.

Fiskeriverket skall verka för en ansvarsfull, långsiktig hushållning med fisktillgångarna och för en bevarad biologisk mångfald. Som en självklar del i detta uppdrag ingår att följa fiskbeståndens utveckling i relation till miljö­tillstånd, resursutnyttjande och klimat. Liksom annan övervakning av vår naturmiljö och dess tillgångar är detta en dyrbar verksamhet som idag är svår att finansiera. Eftersom en samlad nationell databas för dessa resultat tidigare har saknats så startade Fiskeriverket 1996 en gemensam datacentral för att kunna följa fiskets omfattning, intensitet och inriktning i sötvatten, främst de stora sjöarna och större vattendrag. Syftet är att årligen presentera en Resursöversikt Av Sötvattensfisk, inklusive Katadroma och Anadroma arter (RASKA), dvs även ål resp havsöring och lax. En intakt miljö, såväl habitat som vattenkvalitet och -tillgång, är förutsättningarna för fiskfaunan, liksom övrig vattenlevande fauna och flora. I en sådan intakt och naturlig miljö är den biologiska mångfalden störst, dvs där förekommer rätt arter i sin normala numerär och med den genom årtusendena anpassade genuppsättningen. Den friska miljön, hög biologisk mångfald och goda förutsättningar för fiskbestånden går hand i hand. Därför är det naturligt att i RASKA inkludera även en övervakning av den biologiska mångfalden i sötvatten.

Det bör betonas att detta är en resursöversikt och inte Fiskeriverkets handlingsplan förden framtida fiskevården. Resursöversiktenpresenteras avRASKÄ-gruppen till Fiskeriverketoch övriga berörda som ett underlag för framtida åtgärder.