Making the ecosystem approach operational—Can regime shifts in ecological- and governance systems facilitate the transition?

Making the ecosystem approach operational—Can regime shifts in ecological- and governance systems facilitate the transition?

Marine Policy 34 (2010) 1290–1299 Contents lists available at ScienceDirect Marine Policy journal homepage: www.elsevier.com/locate/marpol Making t...

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Marine Policy 34 (2010) 1290–1299

Contents lists available at ScienceDirect

Marine Policy journal homepage: www.elsevier.com/locate/marpol

Making the ecosystem approach operational—Can regime shifts in ecological- and governance systems facilitate the transition? c d ¨ sterblom a,b,n, A. Gardmark ˚ ¨ c, B. Muller-Karulis ¨ H. O , L. Bergstrom , C. Folke b,e, M. Lindegren f, g b h a a h ¨ M. Casini , P. Olsson , R. Diekmann , T. Blenckner , C. Humborg , C. Mollmann a

Baltic Nest Institute, Stockholm Resilience Centre, Stockholm University, SE-106 91 Stockholm, Sweden Stockholm Resilience Centre, Stockholm University, SE-106 91 Stockholm, Sweden c ¨ regrund, Sweden Institute of Coastal Research, Swedish Board of Fisheries, Skolgatan 6, SE-742 42 O d Latvian Institute of Aquatic Ecology, 8 Daugavgrivas, LV-1048 Riga, Latvia e Beijer Institute of Ecological Economics, The Royal Swedish Academy of Sciences P.O. Box 50005, SE-104 05 Stockholm, Sweden f National Institute of Aquatic Resources, Technical University of Denmark, Charlottenlund Slot, Charlottenlund DK-2920, Denmark g Institute of Marine Research, Swedish Board of Fisheries, P.O. Box 4, SE 453 21 Lysekil, Sweden h Institute for Hydrobiology and Fisheries Science, University of Hamburg, Grosse Elbstrasse 133, D-22767 Hamburg, Germany b

a r t i c l e in f o

a b s t r a c t

Article history: Received 12 April 2010 Received in revised form 27 May 2010 Accepted 27 May 2010

Effectively reducing cumulative impacts on marine ecosystems requires co-evolution between science, policy and practice. Here, long-term social–ecological changes in the Baltic Sea are described, illustrating how the process of making the ecosystem approach operational in a large marine ecosystem can be stimulated. The existing multi-level governance institutions are specifically set up for dealing with individual sectors, but do not adequately support an operational application of the ecosystem approach. The review of ecosystem services in relation to regime shifts and resilience of the Baltic Sea sub-basins, and their driving forces, points to a number of challenges. There is however a movement towards a new governance regime. Bottom-up pilot initiatives can lead to a diffusion of innovation within the existing governance framework. Top-down, enabling EU legislation, can help stimulating innovations and re-organizing governance structures at drainage basin level to the Baltic Sea catchment as a whole. Experimentation and innovation at local to the regional levels is critical for a transition to ecosystem-based management. Establishing science-based learning platforms at sub-basin scales could facilitate this process. & 2010 Elsevier Ltd. All rights reserved.

Keywords: Diffusion of innovation Ecosystem approach Marine governance Regime shift Resilience

1. Introduction Complex ecosystems continuously change and managing for their resilience (their capacity to absorb disturbance and reorganize while undergoing change, in order to retain their structure and function) [1] requires an adaptive governance strategy [2]. Adaptive governance conveys the difficulty of control, the need to proceed in the face of uncertainty, and the importance of dealing with diversity and conflict among stakeholders, who differ in values, interests, perspectives and power [3]. Such governance requires co-ordination that enables self-organization and adaptive co-management of ecosystems [4]. For such governance to be effective, an understanding of both ecosystem dynamics and social–ecological interactions is needed [5].

n Corresponding author at: Baltic Nest Institute, Stockholm Resilience Centre, Stockholm University, SE-106 91 Stockholm, Sweden. Tel.: + 46 8 674 76 64; fax: + 46 8 674 70 20. ¨ sterblom). E-mail address: [email protected] (H. O

0308-597X/$ - see front matter & 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.marpol.2010.05.007

Governance systems designed to deal with complexity often rely on multi-level arrangements where authority has been reallocated upward, downward and sideways away from central states [6–8]. It has been proposed that such diverse structures can address environmental problems at multiple scales and nurture diversity for dynamic responses, thereby complementing top down, command and control management [9–11]. In policy terms, there are many similarities between adaptive co-management and the ecosystem approach to management, as defined in the Convention of Biological Diversity [12] (www.cbd.int/ecosystem, Table 1). In principle, the ecosystem approach entails that scales of management should be matched to relevant ecological scales, in order to manage for maintained structure, function and resilience. The ecosystem approach is commonly featured in marine policy documents, but managers commonly struggle with its interpretation and practical implementation [13–15]. It is not uncommon to apply a narrow definition of the concept, focusing on the effects of fishing on non-target species, or other food webrelated issues [16]. This ‘‘food web approach’’ often lacks the important human dimension [17] thereby only involving parts of

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Table 1 Malawi principles for the ecosystem approach [2]. (1) Management objectives are a matter of societal choice. (2) Management should be decentralized to the lowest appropriate level. (3) Ecosystem managers should consider the effects of their activities on adjacent and other ecosystems. (4) Recognizing potential gains from management there is a need to understand the ecosystem in an economic context, considering e.g., mitigating market distortions, aligning incentives to promote sustainable use and internalizing costs and benefits. (5) A key feature of the ecosystem approach includes conservation of ecosystem structure and functioning. (6) Ecosystems must be managed within the limits to their functioning. (7) The ecosystem approach should be undertaken at the appropriate scale. (8) Recognizing the varying temporal scales and lag effects which characterize ecosystem processes, objectives for ecosystem management should be set for the long term. (9) Management must recognize that change is inevitable. (10) The ecosystem approach should seek the appropriate balance between conservation and use of biodiversity. (11) The ecosystem approach should consider all forms of relevant information, including scientific and indigenous and local knowledge, innovations and practices. (12) (12) The ecosystem approach should involve all relevant sectors of society and scientific disciplines.

the identified elements of an ecosystem approach (Table 1). Furthermore, the appreciation of complex systems and potential regime shifts is yet to be incorporated in marine ecosystem-based management [18]. The ecosystem approach has to involve a coevolution between science and policy [19] and also emphasize the importance of governance1 [20,21]. The ecosystem approach is knowledge intensive and requires a thorough understanding of ecosystem structure and function, the dynamics of ecosystem services and their driving forces, spatial resilience of sub-systems within the ecosystem and response diversity of species and functional groups. The literature on ecosystem-based management, e.g., [22,23] is only recently [24–27] starting to include empirically based insights into strategies that make transitions to such management possible. Here, we attempt to describe the social–ecological process of making the ecosystem approach operational. The Baltic Sea, a large marine ecosystem with multiple governance structures, is used as an example. The questions investigated are: (1) How can current understanding of ecosystem dynamics contribute to operational ecosystem-based management (given the current governance framework)? (2) What ecological and governance information is still lacking to implement ecosystem based management? The aim of this synthesis is to contribute to the understanding of how adaptive ecosystem governance regimes can evolve in a large marine ecosystem, and to identify governance processes that facilitate implementation of an ecosystem approach.

2. Ecological knowledge for understanding and managing complex ecosystems According to the ecosystem approach (Table 1), the objectives for management should be a matter of societal choices. However, 1 Defined as the formal and informal arrangements, institutions and mores that structure how resources or an environment are utilized, how problems and opportunities are evaluated and analyzed, what behavior is deemed acceptable or forbidden, and what rules and sanctions are applied to affect the pattern of use [20].

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an overall objective is the preservation of ecosystem structure and function (Table 1). Ecological knowledge required for ecosystembased management includes an understanding of ecosystem structure (patterns) and dynamics (processes), the functions that the ecosystem provides (goods and services), and ecosystem responses to change, such as environmental variation and anthropogenic pressures (addressing the issue of resilience). Where differences in priorities between geographic scales and interest groups are expected, scientific understanding needs to be clear about ecosystem interactions and potentially conflicting objectives, as well as the appropriate scales at which these issues can be addressed. Producing the ecological knowledge needed for an ecosystem approach is a substantial challenge. Marine sciences is commonly fragmented, with separate research groups studying either open sea or coastal ecosystems, or pelagic or benthic food webs, and where fisheries scientists have a different focus than marine ecologists. An integration of this scientific knowledge from the Baltic Sea is presented below. 2.1. The Baltic Sea ecosystems The Baltic Sea in its present state is a young (  4000 years) brackish-water ecosystem that consists of a number of topologically defined sub-basins, here defined as the Sound (S: the western Baltic transition zone to the North Sea), the Central Baltic (BP) deep basins, the shallower Gulfs of Riga (GR) and Finland (GF) and in the north the Bothnian Sea (BS) and the Bothnian Bay (BB), (Fig. 1). These are subject to a gradient in temperature and salinity, decreasing from south to north, which primarily results in decreasing biodiversity with increasing latitude [28]. The Central Baltic Sea includes the Bornholm and Gotland Basins and the Gdansk Deep (Fig. 1), the main spawning areas for cod (Gadus morhua) and sprat (Sprattus sprattus), and the main feeding grounds for herring (Clupea harengus). The BP is one of the most thoroughly investigated systems when it comes to understanding long-term food web dynamics and change, especially for these commercially important fish species [29–31]. The waters of the Gulfs of Bothnia (BB and BS), Finland (GF) and Riga (GR), (Fig. 1) are partially separated from the BP, and these ecosystems have characteristic patterns and dynamics. However, all basins share common responses to some, mainly climate-related, external driver [32]. Also, many marine species of the BP typically migrate into the Gulfs seasonally (e.g., herring), or extend their distributions into these areas during periods of high abundance (e.g., cod and sprat; [33]). The coastal ecosystems are typically structurally complex and locally variable in comparison to the open sea, and there are also large regional differences. Archipelago areas typically dominate the northern coastal areas, bays and sounds dominate the southwestern coasts, where sandy beaches make up large parts of the southern Baltic Sea, forming an almost linear coastline [34] with extended lagoon systems (Oder, Vistula and Curonian lagoon). Individual coastal ecosystems are often defined by their habitat structure, as habitat type has a strong influence on species diversity and distribution. Habitat structure fundamentally depends on topography, which affects local depth patterns (influencing light regimes), and the level to which an area is exposed to wave action (influencing the bottom substrate). In addition, terrestrial influences are of high importance, especially the distance to freshwater outflows, land use dynamics (influencing diffuse nutrient loads) and coastal constructions. 2.2. Goods and services from the Baltic Sea ecosystems The 84 million people inhabiting the drainage area [35] derive a number of goods and services from the Baltic Sea.

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Fig. 1. The Baltic Sea and its drainage area, including population densities, depth profiles and features mentioned in the text.

One important good is the production of fish for human consumption and for industrial purposes. The area also has a high recreational value (tourism, recreational fisheries, boating) and several of these services depend on water quality and the status of fish stocks. In addition, there are historical and cultural values associated with resource uses. The Baltic Sea is also intensively used for transportation, and was designated as a Particularly Sensitive Sea Area (PSSA) by IMO in 2005 (demanding the provision of safe traffic routes). Other uses include extraction of e.g., gravel and increasing interest in the establishment of offshore wind- and wave energy farms. Human use of these ecosystem goods and services affect the ability of the ecosystem to provide these functions. For example, maritime traffic has resulted in an increased load of non-native species through ballast water discharge [36]. Overfishing of cod has not only decreased the productivity of this stock [30], thereby affecting both commercial and recreational use, but has altered overall fish productivity and food web dynamics [37]. A decline in fish stocks is also seen to potentially increase symptoms of eutrophication in coastal [38] and open sea [39] systems, calling for an integrated view on ecosystem management. 2.3. Large-scale changes in ecosystem structure and function The Baltic Sea ecosystems underwent ecological regime shifts2 [40]—in the late 1980s [37,41], both in the open sea, as well as in some coastal areas [32,41]. In the Central Baltic Sea the food web 2 Here defined as a structural change in the ecosystem across multiple trophic levels over large geographical scales.

changed from a cod- to a sprat-dominated state [39]. Climateinduced hydrographic changes have been identified as the main – but not sole – cause of the Central Baltic Sea ecosystem regime shift [37]. In large ecosystems, multiple drivers influence ecological regime shifts [42,43]. In the case of the Central Baltic, overfishing decreased the resilience of the cod stock and made it vulnerable to changes in hydrographic conditions [44]. A lack of inflow of saline water from the North Sea, combined with anthropogenic eutrophication, resulted in oxygen deficiency in the deepwater layers where cod eggs are neutrally buoyant [45,46], leading to increased cod egg mortality. Furthermore, predator–prey feedback loops have been identified, with a high sprat stock exerting high predation pressure on cod eggs and larval food [47]. Overfishing as well as eutrophication has been identified as additional drivers of regime shifts in the other subbasins, along with the predominant effect of altered climate forcing [48]. Another example of the effect of multiple, anthropogenic and climatic drivers is the altered benthic community in the Sound. A change in dominance from filter-feeding molluscs to polychaetes was observed [49] under increasing temperatures, decreasing nutrient loads and primary production [50,51]. These changes coincided with the introduction and spread of the nonnative polychaete Marenzelleria viridis (a common hitch-hiker of ballast water) to the Baltic Sea [52] and the Sound [53]. The observed regime shifts with large-scale changes in ecosystem structure have substantially affected ecosystem function. Following the collapse of the cod stock in the Central Baltic Sea, sprat was released from predation [39,53–55] and in combination with temperature-driven high recruitment success and increased availability of the warm-water copepod species Acartia spp., the sprat stock rose to unprecedented levels [55]. These changes appear to have altered the productivity and regulation of zooplankton in the food web [56] as well as potentially influenced the phytoplankton biomass in summer [39]. The zooplankton community is regulated by climate at lower sprat abundance but top-down controlled by sprat predation at high sprat stock levels [56]. Thus, the ecological regime shift (influenced both by climate and overfishing) and the trophic cascade that followed changed the regulation of the zooplankton community from being bottom-up (climate) controlled, to topdown (predation) regulated, with implications also for clupeid growth structure [57]. This emphasizes the importance of toppredators in maintaining ecosystem functioning. Furthermore, the dual response of zooplankton to climate or predation by sprat potentially has implications for both cod and ecosystem recovery [39]. In contrast, in the Sound, where a regime shift has also been observed [49], no signs of cod collapse or trophic cascades were found [41]. Whereas atmospheric forcing and the immediate effects are similar, there is a major difference in anthropogenic forcing, as trawl fishing has been banned in the Sound since 1932 [58]. Thus, in the absence of overfishing, ecosystems may respond differently both to external forcing and to the ecological regime shifts that may follow.

2.4. Ecological resilience—how serious are the ecosystems shifts? The ecosystem regime shifts in the Baltic Sea sub-basins have resulted from multiple stressors: hydro-climatic changes combined with overfishing and/or nutrient loading. Thus, although ecosystems can, potentially, withstand single pressures, multiple anthropogenic stressors acting jointly have a fundamental impact on ecosystem structure and function [42]. The capacity of an ecosystem to persist in the face of change and to reorganize after a disturbance depends on its resilience [1]. The differences in the regime shifts that occurred in the Central Baltic Sea (where a

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trophic cascade significantly altered ecosystem structure) and in the Sound (with no indications of a trophic cascade), suggests that single pressures (overfishing of cod) can erode ecosystem resilience, thereby making it more vulnerable to variations in climate [59,60]. A crucial question is whether the different ecological regimes described above represent true alternative stable states. If this is the case it would imply that restoring the ecosystem to a more desired state following a regime shift could involve drastic and expensive interventions [61,62]—if at all possible. For the Central Baltic Sea it has been shown that the biotic part of the ecosystem remained in the new regime, while the external forcing variables (hydro-climatic variables, nutrients and fishing pressure) have returned to the state before the regime shift [37]. This indicates that a new state in the food web can have been stabilized by feedback loops (hysteresis mechanisms) [61]; see [28,29,56,57,61–64] for examples of potential such mechanisms in the Baltic Sea.

2.5. Ecosystem linkages The active movement of species provides a link between ecosystems by the transport of energy, predation pressure, competition pressure and genetic variation, but also potentially for the transport of toxins. For example, salmon migrates from freshwater rivers in northern Sweden to the open sea in the southern Baltic, and back again. Herring and sticklebacks migrate between feeding areas in the open sea to spawning habitats in coastal areas. Fish as well as zooplankton perform vertical daily migrations, linking benthic and pelagic food webs in the open sea ecosystem. Water masses containing different levels of salinity, temperature and oxygen, but also different levels of nutrients, toxins and living planktonic organisms (including drifting fish larvae) are transported along main currents, and between open sea and coastal areas. Water exchange between sub-basins and between coastal and open areas depends on the water balance of the individual basin and on topography. The level of water exchange among sub-basins drives the distribution of nutrients as influenced by external and internal nutrient loading, and also determines the effectiveness of nutrient load reduction. Subbasins closer to the input of, comparably, nutrient poor North Sea water and with shorter water residence times, generally respond faster to nutrient load reductions [65]. The central part of the Baltic Sea has a water residence time of several years and the accumulated nutrient pools stored in the deep layers and sediments trigger internal nutrient loading (especially P) that by far exceeds the external nutrient load by rivers [66]. Nutrient transformations within coastal areas also depend largely on water residence time [67]. Systems with little water exchange to open areas are most sensitive to local eutrophication, but at the same time show the fastest response to reduced nutrient input [68,69]. Through run-off, diffuse or via inlets, water movement also links coastal marine waters to freshwater ecosystems, as well as to land use affecting run-off. With the exception of relatively pristine estuaries in the Gulf of Bothnia [70], coastal areas derive the majority of their nutrient budget from terrestrial sources and consequently have higher nutrient concentrations than adjacent open sea areas [69,71,72]. The southern Baltic Sea coastal areas receive the highest nutrient load from rivers, and point sources related to land use and population patterns [71], which is reflected in a strong impact from freshwater run-off close to the large river mouths of the southern and southeastern Baltic [73]. Except for the Vistula, the major eutrophicated rivers of the Baltic Sea flow into sheltered lagoons or gulfs (Fig. 1). The lagoon

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systems along the southern and southeastern Baltic Sea shore; the Oder lagoon (Oder), Vistula lagoon (Pregolia) and the Curonian lagoon (Nemunas), but also the Gulf of Riga (Daugava) are most affected by eutrophication [74]. However, once the river waters have passed these lagoons and gulfs they are rapidly dispersed along the southern coasts. These open coastlines have a short water residence time compared to the sheltered bays and archipelago areas that are more common in the northern areas [75]. The larger water exchange from these southern coastal areas to the open sea link the large nutrient input to these coastal areas to the Central Baltic Sea. 2.6. Management challenges identified from our ecological understanding The review above indicates that many ecological sub-systems of the Baltic Sea have exhibited non-linear thresholds, and that the common driver of these is climate. It further suggests that multiple drivers – climate and overfishing and/or eutrophication – have potentially eroded the resilience of the systems and hence the capacity to respond to changes in climate. These potentially synergistic drivers of regime shifts differ between sub-basins, indicating that sub-basin dynamics (coastal-offshore interactions) may be stronger than inter-basin dynamics. This identifies a number of challenges for governance. Shifts to alternative regimes that may be stabilized by feedback mechanisms (a low cod state) underlines the importance of an ecosystem approach. Multiple drivers at several scales cause problems in defining appropriate scales for management and defining responsibilities (and actions) for achieving objectives. Management at small geographic scales may result in fast ecosystem response where there are weak linkages to adjacent ecosystems. For sub-basin scales however, the relative importance of within and between sub-basin dynamics will determine the appropriate scales of management.

3. Current governance of the Baltic Sea As in many areas, environmental policies in the Baltic Sea region have been developed on a sector-by-sector basis (environmental, agricultural, fisheries). Since the 1970s the Helsinki Commission (HELCOM) has been the main forum for international environmental cooperation (all riparian states are members) [76]. The ecosystem approach has, since 2003, been the accepted framework for HELCOM [77]. The organization has however, not been able to reduce the negative effects of eutrophication (a prioritized area) despite almost three decades of political declarations [78]. Implementation of agreed measures is hampered by the voluntary nature of HELCOM cooperation, and the lack of sanctioning mechanisms. EU legislation and policies, in contrast, have strong sanctioning mechanisms and is increasingly encompassing marine related issues. 3.1. Large-scale changes in governance structure and function The Helcom Baltic Sea Action Plan (BSAP) [79] address biodiversity conservation, hazardous substances and shipping, and has contributed to an ecosystem approach for reducing eutrophication. Total allowable nutrient inputs (critical loads defined to achieve ecological targets) have been calculated and specific country-wise nutrient reduction targets have been allocated. In addition to this recent change in regional governance of eutrophication-related issues, there has been a range of recent policy developments, which supports a transition to an ecosystem

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approach. The accession of the Baltic States (Estonia, Latvia and Lithuania) to the European Union in 2004, has led to the application of a number of top-down changes in governance frameworks, enabling regional institutional changes. These include the implementation of the habitat [80] and bird [81] directives which influence spatial and species protection measures [82,83]. Importantly, the EU Water Framework Directive [84] has changed the geographical scales at which inland and coastal waters are managed (Table 2), which provides an opportunity to shift from conventional to more adaptive water management and governance approaches [85]. The European Common Fisheries Policy (CFP) reform in 2003 put a larger focus on the ecosystem approach and regional seas and has led to an increased dialogue between actors in Regional Advisory Councils (RACs) [86]. Although this change may be rather insignificant from a perspective of influencing policy outcomes [87], it may constitute an important step towards more regional based co-management of fisheries, emphasized in the current CFP reform process (2009–2012) [88]. The EU Marine Strategy Framework Directive (MSD) [89] constitutes a new framework for the governance of marine resources throughout Europe and could provide a novel approach for regional social–ecological innovation. At an even higher political level, the EU commission is currently developing an Integrated Maritime Policy (in which the Marine Strategy Directive is to form the environmental component) addressing a wider set of issues such as globalization and competitiveness, climate change, the marine environment, maritime safety, energy security and sustainability [90]. These two policies may provide mechanisms for integration between water quality, agricultural, fisheries and other policies areas [91]. Maritime spatial planning [92] is intended to be a key instrument for the Integrated Maritime Policy. These institutional changes result in new perspectives on the scales and basis for management. Ecologically defined space (i.e., watersheds or large marine ecosystems, rather than administrative regions) is increasingly becoming the starting point for European marine-related policies. The conservation of ecosystem structure, function and resilience is becoming a more clearly articulated priority. However, achieving this in practice often means dealing with conflicting interests.

3.2. The implementation gap Changing policies often start with a change in mental model [1], i.e., the perception of ‘‘how the system works’’. Changes in public perception of the Baltic Sea, from a linear, reversible

system that is easy to repair, to a system that potentially have gone through regime shifts, resulting in algal blooms [93] and depleted fish stocks, has likely contributed to the political will in some countries to invest political capital in the Baltic Sea. However, cultural diversity can limit the prospects for finding shared interests and understanding [11] and the environmental situation in the Baltic Sea is still much of a non-issue in several countries. The countries introducing the EU Water Framework Directive tackled this practical implementation problem with a Common Implementation Strategy (CIS). The CIS working groups, among other, coordinate the intercalibration of ecological status assessment, leading to an EU Council decision on mandatory water quality class boundaries for member states [94]. Such efforts to create shared understanding of processes and problems are key for developing coherent implementation. A shared mental model at the political level is crucial for successful implementation of an ecosystem-based approach. Ministers of environment in HELCOM countries took a radical decision when agreeing on the nutrient reduction scheme within the HELCOM BSAP, despite differences in perception of the problems and the investments necessary to address them. Also, the Council of Fisheries Ministers in the EU took a historical decision in October 2008, when deciding on quotas for cod in line with recommendations from the International Council for the Exploration of the Seas (ICES), for the first time in over a decade. Despite national differences, shared perception of the need for political priority of these issues may be developing. Making the ecosystem approach operational requires leadership and communication skills. Trust building, sense making, the linking of key individuals, partnerships between actor and the development of shared vision can mobilize momentum for change [2,95–97]. Leadership means dealing with conflict, e.g., relating to competition for space (transport, fishing, offshore energy) [82]. Conflict between stakeholders may develop at several levels: between upstream and downstream water users, or between different categories of fishermen (small- or large scale commercial or recreational fishing). Dealing with conflict needs to take place at all geographical levels. Olsen [98] has developed a framework for evaluating progress towards the implementation of the ecosystem approach, by classifying four orders of outcome. The large-scale changes in the governance framework described here primarily represent examples of enabling conditions, or 1st order outcomes. However, relatively limited progress is currently being accomplished at the Baltic Sea level towards 2nd order outcomes, or changes in behavior and 3rd order outcomes, or harvest, where some social and environmental quality is maintained, restored or improved

Table 2 Large-scale changes in the governance framework. Policy

Scale

Targets

Geographical scope

The Baltic Sea Action Plan 2007

Baltic Sea

EU Water Framework Directive 2000 The 2003 Common Fisheries Policy reform

National water districts (inland and coastal waters)

Reach defined targets for total nitrogen (N) and phosphorous (P) emissions Reach ‘‘Good ecological status’’ in national water district

Scientific targets defined by ecosystem model at Baltic Sea and sub-basin levels Geographical boundaries define the scale of management

The EU Marine Strategy Directive 2007

Reach ‘‘Good environmental status’’

Emphasis on ecosystem based approach

Institutional change

Mandate Voluntary agreement - no sanctioning mechanisms

Water governing authorities established

Legally binding

Regional Advisory Council (including fisheries and environmental interest groups) established Address all human activities, including policy coherence

Regional Advisory Council are consulted by the Commission Legally binding

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[98]. The 4th order outcome is described as Sustainable Coastal development, a more distant goal for the region. However, interesting progress encompassing both 2nd and 3rd order outcomes can be observed at local levels (see below). In complex systems where diverse stakeholders interact, users will attach different priorities to social and environmental objectives. The level of scientific consensus about ecological dynamics and drivers affecting the system will also influence the definition of e.g., 4th order outcomes. 3.3. Small scale pilot initiatives create implementation capacity Reaching targets for marine policies requires adequate resources for implementation and empowerment of stakeholders. A range of pilot initiatives (Table 3) has been launched to create new capacity to reach objectives in different policy areas. Swedish national environmental quality objectives related to eutrophication led to the establishment of the Focus on nutrients project (Table 3, www. greppa.nu), which has created an environment for mutual (social) learning between farmers, agricultural scientists and managers. It has also stimulated an interest in adjacent countries (S. Olofsson, Swedish Board of Agriculture, pers.com). Another example of bottom-up driven governance change can be illustrated by actions taken by local resource users as a response to national (Swedish) plans to designate a locally important shrimp fishing area as a national park in 1999. The national plans led to the establishment of a fisheries co-management area [99] and this change at the local level stimulated the Swedish Ministry of Agriculture in 2004 to initiate six pilot initiatives for local co-management of fisheries along the Swedish coast [100]. Another pilot initiative for ecosystem-based management is the Kristianstads Vattenrike. The region in southern Sweden used to be a water logged problem area for local resource managers. However, it generates a variety of ecosystem services and in the late 1980s and early 1990s the management changed through local initiatives, e.g., restoration of wetlands [96]. Drawing from insights of promising local pilot initiatives, the Swedish government has recently initiated a number of pilot projects for local-regional implementation of the ecosystem approach in the coastal zone (Table 3). Several of the existing national pilot initiatives were initiated as a response to crises (problems with reaching national targets, risk of losing important fishing grounds, flooding) and illustrate instances where: (1) the scope of management has widened

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from a particular issue to a broader set of issues across scales, (2) management has expanded from individual actors to groups of actors, (3) knowledge of ecosystem dynamics has developed as a collaborative effort and become part of the organizational and institutional structures at multiple levels and (4) social networks have developed to connect institutions and organizations at multiple levels to facilitate information flows, identify knowledge gaps, and create nodes of expertise for flexible and collaborative management. These developments have improved the capacity to deal with uncertainty and surprise [96]. Innovative management experiments are processes which can create novel capacity to deal with ecosystem dynamics and these pilot initiatives are important arenas for innovation, social learning and ecosystem based problem solving across sectors and stakeholder groups [96]. 3.4. Towards successful regional implementation Multiple drivers influence ecosystem dynamics, which differ between sub-basins. The multitude of drivers impacting change (e.g., nutrients from land and offshore fisheries) illustrates the need for integration across the land–water interface and between national and international governance. Improvement of local conditions can be achieved by local actions (coastal wetland protection can improve coastal water quality and stationary fish stocks can be managed locally). Policy change at European and national levels influence management practices and incentives at national and local levels. Local initiatives can also create novel capacity for policy and practice. Successful implementation of the ecosystem approach builds on the interactions between science, policy and practice, from local to European levels. Top-down enabling legislation and bottom-up practices can lead to a diffusion of innovation that affect practices at adjacent scales (Fig. 2). The international development of the Baltic Nest model created led to policy change at the regional (Baltic Sea) level (BSAP), impacting national policy and practice (Fig. 2a). National implementation will impact local and eventually regional levels (a diffusion of innovation, as illustrated by the ovals along the practice-axis). Science-based changes in agricultural practices to reduce nutrients (Fig. 2b) are in part driven by projects at the national level (Focus on nutrients). This project has close feedbacks to science and similar approaches may emerge in other countries. At the same time, policy change at the European

Table 3 Recent (Swedish) pilot initiatives in the Baltic Sea area. Pilot initiative

Policy

Scale

Process

Outcome

Partners

Focus on nutrients 2001-ongoing

CAP, WFD

Individual farms

Reduced nutrients and greenhouse gas emission

Fisheries Co-management 2004–2007

CFP

Local

Environmental information, counseling to reduce losses of nutrient to air and water Establish multi-stakeholder collaboration for increased local autonomy

Swedish Board of Agriculture, local authorities, Federation of Swedish Farmers, etc. Commercial fishermen, NGOs, sports fishermen

Kristianstads Vattenrike (Biosphere reserve) 1989-ongoing

CAP, WFD

Local

Establishment of a boundary organization

Plan fish research project 2008–2013

CFP

National/ local

Investigate the role of zooplanktivores on ecosystem interactions

N.A.

Coastal zone planning 2008

MSD

Regional

Local test of ecosystem based management

N.A.

Exchange of knowledge, conflict mitigation, development of shared visions/goals Integrated management of ecosystem services

International organizations, national, regional and local authorities, corporations, researchers, non-profit associations, farmers, landowners Swedish Board of fisheries, Swedish Environmental Protection Agency (SEPA), International and National Universities, Commercial Fishermen Organizations, environmental NGOs Local stakeholders, coordinated by SEPA

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Fig. 2. Diffusion of innovation and co-evolution between science, policy and practice, when addressing (a) offshore eutrophication, (b) freshwater quality, (c) fisheries management and (d) integrated marine management. Top-down enabling legislation in combination with science and bottom-up driven initiatives is stimulating the movement towards a practical implementation of the ecosystem approach.

level (WFD) is changing national policies as well as national and local practices. The combination of local, national and increasingly regional changes in practices to address eutrophication are influencing the practice-axis at all scales (Fig. 2b). Local pilot initiatives in fisheries co-management (Fig. 2c) stimulated national policy change, facilitating additional local initiatives. The CFP reform is influencing stakeholder dialogue at the regional level (Baltic Sea Regional Advisory Council). Here, practice at the local levels is relatively unconnected to practice at the regional level. European policies are increasingly changing regional and national practices through the Marine Strategy Framework Directive and local pilot initiatives (e.g., Kristianstads Vattenrike) are stimulated along the national coast of Sweden (Fig. 2d). Potentially, national research programs (Table 3) and regional scientific insights (the existence of regime shifts in the respective sub-basins as reviewed here), can impact on national and regional practices, respectively. As in Fig. 2c, there is a lack of diffusion of innovation (Fig. 2d) between local and regional levels, which potentially could be stimulated by an increased focus on sub-basin scales. Changes in policy and practice, with a close link to science, have been evident for the management of water quality (Fig. 2a and b), leading to a change in management regime at all geographical levels for this large marine ecosystem. Local practices and European policy reform is stimulating novel approaches in fisheries governance—although less coherent than changes in water governance. These initiatives have primarily been stimulated by innovation in practice, rather than by science

(Fig. 2c). Policies for integrated marine management are being developed at European and national levels. Practical implementation is currently in an early phase and could be further stimulated by science (Fig. 2d). The described ecological regime shifts and associated drivers have been identified at sub-basin level, where few of the science– policy–practice interactions are operating. The described governance changes have primarily occurred at local, national and the Baltic Sea scales. To our knowledge, few examples exist of bilateral or multilateral cooperation around water quality, fisheries or integrated marine management in the region, focusing on this scale. Potentially, there is a need for developing governance regimes with a capacity for addressing the dynamics at this scale, with a focus from watershed to open sea basins interactions. Such emphasis would likely contribute to reducing existing misfits between ecosystem dynamics and governance structures [5]. A stronger focus on the sub-basin level would allow for enhanced capacity to manage conflict between stakeholders and deal with sub-basin specific multiple drivers of ecological regime shifts. The clarity of a regional management framework (e.g., common methodology and access to data for spatial planning) coupled with a stronger focus on sub-basin monitoring, research, management and adaptation, could contribute with the flexibility suggested necessary for robust governance systems [101]. This implies that any management body at the sub-basin level would maintain a close dialogue with regional management, scientific and stakeholder bodies (such as HELCOM, ICES and the Regional Advisory Council for fisheries, respectively). At this scale,

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co-ordination is likely more feasible than on the regional level. In addition, it would also enable bilateral and multilateral cooperation across national borders and possibly spur social innovations for improved management. Transaction costs are likely initially high for such formalized multi-level governance structures at sub-basin levels. Any initiative would build on existing water authorities and related bodies. Existing evidence suggests that capacity for implementation can increase substantially, once shared vision, action plans (in line with over-arching goals for the region) and monitoring strategies are in place [102,103]. However, successful design of implementation plans requires ambitious public consultations and social/economic impact assessments to ensure accountability and legitimacy [26,104]. This highlights the dilemma of defining targets for implementing an ecosystem approach that on the one hand is inclusive of, and acceptable by stakeholders, and on the other hand takes advantage of political windows of opportunity.

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of ecosystem degradation on the production of desired ecosystem goods and services [17]. The process of defining such matrices requires that scientific expertise, and stakeholder and local knowledge is used constructively. Social–ecological inventories, where ecological inventories are complemented by inventories of local stakeholder groups, interests and management initiatives [113], are necessary for understanding context and potential for collaborative learning and ecosystem based management. Scientific networks could initiate stakeholder inclusive, science-based processes, where emerging learning platforms would contribute with knowledge for regional ecosystem based management. By playing the role of honest broker, one developing role of science could be to bridge critical gaps between science, practice and policy, as well as between stakeholders. Following these processes within the social sciences could lead to important scientific insights about governance of social–ecological systems. Ideally, analogous learning platforms should be set up for the regional (Baltic Sea) level in order to better understand cross-scale interactions in governance structures.

4. Is there a role for science to facilitate a transition? Science has a fundamental role in Baltic Sea policy development. The NEST decision support system (www.balticnest.org) is an ecosystem model and boundary object [105] primarily designed to understand the dynamics and effects of nutrients in the Baltic Sea (including its drainage area). The system was critical for reaching political consensus about reductions of nutrients, aimed at reaching desired environmental status (as defined by HELCOM experts). The NEST model was used to develop an allocation scheme for needed actions, perceived as fair by all governments (F. Wulff, Baltic Nest Institute, pers. com.). This unique method of using a decision support system towards adaptive management shares similarities with the RAINS model used for reducing acidifying substances [106]. The development of the NEST model and recent integrated assessments of Baltic Sea food web dynamics (reviewed above) would have been impossible without access to long-term monitoring data. By using all available data the ICES/HELCOM Working Group on Integrated Assessment (WGIAB) could show that the shift in fish community composition was embedded in a larger restructuring of the ecosystem at all trophic levels [37,49]. Ecosystem based management is information- and thus monitoring-intensive, because the interpretation, and responses to ecosystem feedback at multiple scales require knowledge from a range of different sources [4,107–111]. There is a need also for the social sciences, economics, and interdisciplinary work, in order to be able to evaluate the effectiveness of management options or the role of different incentives, as well as scientific observation of management change processes [26]. The potential for international scientific collaboration in the region is increasing, with recently initiated joint regional research funding (www. bonusportal.org). Importantly, ICES, providing scientific advice for fish quotas, is currently in a reorganization phase. Consequently, its advisory bodies are changing from giving advice on fisheries management, marine environment and ecosystems [112], to a more integrated advice on the ecosystem and its dynamics. This review indicates that more attention should possibly be focused on the sub-basin level. Changes in the scale of management could imply changes for the organization and role of the scientific community. Science could play an important role in facilitating routines for assessments and stakeholder dialogues at the sub-basin level, thereby creating collaborative learning platforms and boundary organizations [105]. Important exercises could include defining use interaction matrices, describing potential conflict between sectors [17] and identification of the negative impacts of human use on ecosystems, as well as impacts

5. Conclusions The ecosystem approach to the management of marine resources is commonly called for, but application differs substantially between regions. Interesting and innovative approaches are however apparent e.g., in the Barents Sea region [114], the Great Barrier Reef [26], the Puget Sound [25] and in the Antarctic [115]. This study illustrates that even a comparatively simple biological marine system, with low species diversity is complex to manage, resulting from ecological regime shifts, cross-scale ecological interactions and social–ecological dynamics. The Baltic Sea is substantially shaped by human activities, some of which have to be managed in an international context, others that can be addressed at local and sub-basin levels. Interesting innovations to address social–ecological dynamics at different spatial scales are emerging, some of which have spread to other spatial scales or sectors. This diffusion of innovation has been made possible through interactions between science, policy and practice. The potential for local innovation and the spread of ideas is emphasized as a key tool for implementing the ecosystem-based approach. Although recent political actions to reduce overfishing and eutrophication, as well as expected future initiatives for marine spatial planning are important, these actions are likely relatively inefficient without stakeholder consultation, engagement and participation across interest groups. Emphasis on multilevel governance structures that provides space for experimenting and spread of social innovations at local and regional scales can provide key elements for stimulating an adaptive capacity for dealing with this dynamic ecosystem and the services generated. One way forward could be to establish a number of stakeholder inclusive collaborative learning platforms at the sub-basin scale—with a clear mandate and with the aim to address spatially relevant dynamics.

Acknowledgements We appreciate the assistance from E. Smedberg and R. Kautsky for the production of Figs. 1 and 2, respectively. This study was in part funded by the EC FP7 project: Knowledge-based Sustainable Management for Europe’s Seas (KnowSeas), Grant agreement no. 226675.

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