The Ecosystem Approach to Fisheries in the
Mediterranean and Black Seas

J. Lleonart and F. Maynou (eds)

INTRODUCTIONTop

The development of the ecosystem approach to fisheries management (EAF) in the European seas is one of the objectives of the new Common Fisheries Policy in Europe (for the countries belonging to the European Union), as well as one of the priorities identified by the World Summit on Sustainable Development globally (WSSD; United Nations 2002United Nations 2002. Plan of Implementation of the World Summit on Sustainable Development. Retrieved from http://www.un.org/esa/sustdev/documents/WSSD_POI_PD/English/WSSD_PlanImpl.pdf (accessed November 2013).).

Given the human use of their coastal environments for a wide range of conflicting activities (e.g. tourism, diving, shipping, fishing and aquaculture), the Mediterranean and Black Seas are affected by several threats. In a recent attempt to quantify the cumulative human impacts on marine ecosystems, Mediterranean marine ecoregions (see Spalding et al. 2007Spalding M.D., Fox H.E., Allen G.R., Davidson N., Ferdana Z.A., Finlayson M., Halpern B.J., Jorge M.A., Lombana A., Lourie S.A., Martin K.D., McManus E., Molnar J., Recchia C.A., Robertson J. 2007. Marine ecoregions of the world: A bioregionalization of coastal and shelf areas. BioScience 57: 573-583.) were classified among the most impacted ecoregions of the world (Halpern et al. 2008Halpern B.S., Waldbridge S., Selkoe K.A, Kappel C.V., Micheli F., D’Agrosa C., Bruno J.F., Casey K., Ebert C., Fox H.E., Fujita R., Heinemann D., Lenihan H.S., Madin E.M.P., Perry M.T., Selig E.R., Spalding M., Steneck R., Watson R. 2008. A global map of human impact on marine ecosystems. Science 319: 948-952., Micheli et al. 2013aMicheli F., Halpern B.S., Walbridge S., Ciriaco S., Ferretti F. 2013a. Cumulative Human Impacts on Mediterranean and Black Sea Marine Ecosystems: Assessing Current Pressures and Opportunities. PLoS ONE 8(12): e79889.). This situation is also due to the effect of extractive fisheries, whose impact has grown in the last 30 years, leading to the over-exploitation of the main commercial stocks in most areas, along with a variety of well-described direct and indirect negative impacts on the ecosystem (Tudela 2004Tudela S. 2004. Ecosystem effects of fishing in the Mediterranean: an analysis of the major threats of fishing gear and practices to biodiversity and marine habitats. Studies and Reviews. General Fisheries Commission for the Mediterranean. No. 74. Rome, FAO. 2004, 44 pp., Llope et al. 2011Llope M., Daskalov G.M., Rouyer T.A., Mihneva V., Chan K.-S. 2011 Overfishing of top predators eroded the resilience of the Black Sea system regardless of the climate and anthropogenic conditions. Glob. Change Biol. 17(3): 1251-1265., Colloca et al. 2013Colloca F., Cardinale M., Maynou F., Giannoulaki M., Scarcella G., Jenko K., Bellido J.M., Fiorentino F. 2013. Rebuilding Mediterranean fisheries: a new paradigm for ecological sustainability. Fish Fish. 14: 89-109.).

The Black Sea ecosystem has been subjected to dramatic changes since the early 1970s, because of the combined effect of successive over-exploitation of fish stocks, the increased pollution and eutrophication of the basin, population outbursts of alien planktonic carnivores and strong decadal-scale climatic fluctuations (Daskalov et al. 2007Daskalov G. M., Grishin A., Rodionov S., Mihneva V. 2007. Trophic cascades triggered by overfishing reveal possible mechanisms of ecosystem regime shifts. PNAS 104: 10518-10523., Oguz and Gilbert 2007Oguz T., Gilbert D. 2007. Abrupt transitions of the top-down controlled Black Sea pelagic ecosystem during 1960–2000: evidence for regime shifts under strong fishery exploitation and nutrient enrichment modulated by climate-induced variations. Deep-Sea Research I 54: 220-242).

In both basins the effect of fishing can be exacerbated by the ongoing rapid warming trend, which is believed to act synergistically with fisheries exploitation and to cause quick changes in fish and shellfish fauna, with likely negative impacts on fisheries sustainability (Daskalov et al. 2008Daskalov G. M., Prodanov K., Zengin M. 2008. The Black Sea Fisheries and Ecosystem Change: Discriminating Between Natural Variability and Human-Related Effects. Am. Fish. Soc. Symp. 49(2): 1649-1664., Ben Rais Lasram et al. 2010Ben Rais Lasram F., Guilhaumon F., Albouy C., Somot S., Thuiller W., Mouillot D. 2010. The Mediterranean Sea as a ‘cul-de-sac’ for endemic fishes facing climate change. Global Change Biol. 16: 3233-3245., Lejeusne et al. 2010Lejeusne C., Chevaldonné P., Pergent-Martini C., Boudouresque C.F., Pérez T. 2010. Climate change effects on a miniature ocean: the highly diverse, highly impacted Mediterranean Sea. Trends Ecol. Evol. 25: 250-260.).

For all these reasons, the development of the EAF in the Mediterranean and Black Seas is considered a priority, though it is challenged by the inherent socio-political complexity of this region, and particularly the high diversity of political and cultural systems and legal jurisdictions (Micheli et al. 2013bMicheli F., Levin N, Giakoumi S., Katsanevakis S, Abdulla A., Coll M., Fraschetti S., Kark S. 2013b. Setting Priorities for Regional Conservation Planning in the Mediterranean Sea. PLoS ONE 8(4): e59038. ). The coastal States in the region often do not share the same management priorities for their fisheries, even if they often exploit the same commercial stocks of fish and shellfish. However, a policy strategy to move in the EAF direction is still far from being developed either at national level (i.e. Mediterranean and Black Sea countries) or international level (i.e. FAO General Fisheries Commission for the Mediterranean Sea) and little progress has been observed in the last few years.

One of the essential components of the EAF is the quantitative analysis of fishing effects by means of ecosystem models. These are mathematical constructs of high complexity that attempt to model the marine ecosystem, ideally with a high degree of realism, in order to assess the effects of fishing on the resource, habitat and stakeholders. Many of the ecosystem models used worldwide in the EAF are based on the mass-balance solution of Ecopath with the Ecosim modelling suite (Walters et al. 2000Walters C.J., Pauly D., Christensen V., Kitchell J.F. 2000. Representing density dependent consequences of life history strategies in aquatic ecosystems: ECOSIM II. Ecosystems 3: 70-83.), but other options exist, such as Osmose (Shin and Cury 2001Shin Y-J., Cury P. 2001. Exploring fish community dynamics through size-dependent trophic interactions using a spatialized individual-based model. Aquat. Living Resour., 14: 65-80.) and Atlantis (Fulton et al. 2011Fulton E.A., Link J.S., Kaplan I.C., Savina-Rolland M., Johnson P., Ainsworth C., Horne P., Gorton R., Gamble R.J., Smith A.D.M., Smith D.C. 2011. Lessons in modelling and management of marine ecosystems: the Atlantis experience. Fish Fish. 12: 171-188.). Plagányi (2007)Plagányi E. E. 2007. Models for an ecosystem approach to fisheries. FAO Fish. Tech. Paper 477: 1-126. provides a comprehensive review of these models and many others. In the Mediterranean and Black Seas, several ecosystem models have been developed (Pranovi et al. 2003Pranovi F., Libralato S., Raicevich S. 2003. Mechanical clam dredging in Venice lagoon: Ecosystem effects evaluated with a trophic mass-balance model. Mar. Biol. 143(2): 393-403., Brando et al. 2004Brando, V. E., Ceccarelli, R., Libralato, S., Ravagnan, G. 2004. Assessment of environmental management effects in a shallow water basin using mass-balance models. Ecol. Modell. 172(2-4): 213-232., Coll et al. 2007Coll M., Santojanni A., Palomera I., Tudela S., Arneri E. 2007. An ecological model of the Northern and Central Adriatic Sea: Analysis of ecosystem structure and fishing impacts. J. Mar. Syst. 67(1-2): 119-154., 2008Coll M., Palomera I., Tudela S., Dowd M. 2008. Food-web dynamics in the South Catalan Sea ecosystem (NW Mediterranean) for 1978-2003. Ecol. Model. 217(1-2): 95-116., Tsagarakis et al. 2010Tsagarakis K.; Coll M., Giannoulaki M., Somarakis S., Papaconstantinou C. 2010. Food-web traits of the North Aegean Sea ecosystem (Eastern Mediterranean) and comparison with other Mediterranean ecosystems. Est. Coast. Shelf Sci. 88(2): 233-248., Coll and Libralato 2012Coll M., Libralato S. 2012. Contributions of food web modelling to the ecosystem approach to marine resource management in the Mediterranean Sea. Fish Fish. 13(1): 60-88.), but they have not been applied in practice for fisheries management. Owing to the extreme complexity of some of these models and the long development time required (typically, 3-4 years), some authors advocate minimum realistic models (e.g. the GADGET model, Taylor and Stefánsson 2004Taylor L., Stefansson G. 2004. Gadget models of cod-capelin-shrimp interactions in Icelandic waters. ICES CM 2004/FF: 29.) or models of intermediate complexity for ecosystem assessments (MICE) (Plagányi et al. 2012Plagányi E. E., Punt A.E., Hillary R., Morello E.B., Thebaud O., Hutton T., Pillans R.D., Thorson J.T., Fulton E.A., Smith A.D.M., Smith F., Bayliss P., Haywood M., Lyne V., Rothlisberg P.C. 2012. Multispecies fisheries management and conservation: tactical applications using models of intermediate complexity. Fish Fish. ), as a reasonable compromise for the application of ecosystem models in the EAF. However, the EAF can also be implemented through the relatively model-free indicator approach (Cury et al. 2005Cury P.M., Shannon L.J., Roux J. P., Daskalov G. M., Jarre A. 2005. Trophodynamic indicators for an ecosystem approach to fisheries. ICES J. Mar. Sci. 62(3): 430-442., Didier et al. 2010REF, Shin et al. 2010Shin Y.-J., Shannon L.J., Bundy A., Coll M., Aydin K., Bez N., Blanchard J. L., Borges M.F., Diallo I., Diaz E., Heymans J.J., Hill L., Johannesen E., Jouffre D., Kifani S., Labrosse P., Link J. S., Mackinson S., Masski H., Mollmann C., Neira S., Ojaveer H., Ould Mohammed Abdallahi K., Perry I., Thiao D., Yemane D., Cury P.M. 2010. Using indicators for evaluating, comparing, and communicating the ecological status of exploited marine ecosystems. 2. Setting the scene. ICES J. Mar. Sci. 67(4): 692-716.).

In 2011 the European Commission launched the Concerted Action CREAM (Coordinating research in support to application of EAF (Ecosystem Approach to Fisheries) and management advice in the Mediterranean and Black Seas, 7th Framework Programme), involving 22 fisheries research institutions of the Mediterranean and Black Seas focusing on the EAF. The main objective of the project was to establish the guidelines for the application of the EAF in the region and, to this end, to identify the current supporting knowledge.

In the framework of the above Concerted Action the present work was carried out, with the main objective of performing a critical review of the current understanding related to the ecosystem approach of fisheries management (EAF) in the Mediterranean and Black Seas and to assess, by means of expert evaluation, the priority research actions for the development of the EAF. The specific objectives were i) to collate information on the research topics relevant to the EAF financed in the last 10 years either in Mediterranean or the Black Sea; and ii) to carry out a survey among CREAM participants about their current understanding of the capacity to address relevant EAF issues.

MATERIALS AND METHODS Top

A critical review of the current understanding related to the EAF in the Mediterranean and Black Seas was carried out, involving experts from 22 institutions of the Mediterranean and Black Seas (Fig. 1). All the available information on research topics relevant to the EAF financed in the last 10 years either in the Mediterranean or the Black Sea was gathered, classified and evaluated.

This exercise was performed according to two main steps:

1) All the information potentially associated with EAF topics related to various types of activities (e.g. research projects, monitoring programmes, advice and other initiatives) carried out by the 22 institutions in the last 10 years was explored in relation to the key aspects associated with the EAF and fishery management. This review was performed according to a common protocol and using a standard template to store and summarize all the information gathered.

The information collected was analysed, classifying each activity according to:

- Its type: research projects, monitoring programmes, advice to public administrations, other.

- Its geographical coverage: local or national scale, Mediterranean or Black Sea scale, wider scale (e.g. Mediterranean and North Atlantic).

- The main topics dealt with: descriptions of fisheries (e.g. characteristics of fleets, fishing capacity/effort, landings), descriptions of species/habitats (e.g. species composition, size/age structure, biological parameters, biocenosis description), modelling (ecological and/or bio-economic), stock assessment and/or management suggestions (suggestions for regulation of fishing effort, for technical measures, for spatial management, etc.).

2) Each expert of the 22 institutions involved in this study provided an evaluation, by means of an overall assessment, of the activities/projects/initiatives taken into account, of the capacity to address, in his or her country, the issues related to the implementation of the EAF. These issues were divided into the following main topics, which reflect the FAO technical guidelines in research for EAF implementation (FAO 2003FAO 2003. The ecosystem approach to fisheries. FAO Technical Guidelines for Responsible Fisheries, No. 4 (Suppl. 2). FAO Fisheries Department. Rome, FAO, 112 p.):

1) Fisheries structure and fleets.

2) Fisheries impacts and other anthropogenic impacts.

3) Species/habitat knowledge.

4) Socio-economic aspects and modelling (ecosystem and bio-economic).

5) Assessment of management measures.

6) The management process.

7) Monitoring and assessments.

The capacity to address each issue was evaluated according to a simple qualitative scale:

- None, absolute lack of knowledge.

- Low, scarce and scattered knowledge in both space and in time.

- Medium, fairly broad knowledge, but mostly qualitative.

- High, extensive and detailed knowledge, also supported by quantitative analyses.

All the information reviewed from the experts was stored in common tables and pooled and summarized at main basin level (western Mediterranean, central Mediterranean, eastern Mediterranean, Black Sea). A simple score system was used (from 0 to 3, corresponding to the evaluations ranging from “none” (0) to “high” (3).

All this work was finalized in a specific workshop held at the FAO GFCM headquarters in Rome on 30-31 May 2012. The workshop was fundamental to standardize this common work and the procedure of analysis.

RESULTSTop

Information coming from about two hundred different types of activities possibly related to the EAF context was gathered by the experts involved in this study. Table 1 provides an example of several research projects/monitoring programmes/advice/other initiatives, showing how this information is wide, detailed and, in many cases, very heterogeneous.

Tables 2, 3 and 4 summarize the information gathered according to the type of activity, the geographical coverage and the main topics dealt with. No substantial differences were detected among the four main basins considered.

Most of the information considered (34.5% to 53.3% according to each basin) is related to research projects (Table 2). Information from monitoring programmes was also collected in large amounts (16.4% to 31%), mostly concerning routinely and standardized fishery-dependent or -independent data collection programmes such as those running under the European Union Data Collection Framework. Activities related to various types of advices to support public administrations in fishery management represent 8% to 24% of the information collected, with the highest percentage being observed for the Black Sea.

As regards geographical coverage, the majority of the activities analysed (56.7% to 69.0%) of the total (Table 3) are performed in fairly wide areas, but within the boundaries of the Mediterranean and Black Seas. Only for the western Mediterranean institutions, a large proportion of the activities considered affect very wide areas.

The information collected deals with three main topics (Table 4):

- From 26.8% to 37% of the information deals with descriptions of fisheries characteristics (e.g. characterization of fleets, fishing gears, distribution of fishing effort, statistic on landings, CPUE, etc.).

- Studies at species level (e.g. distribution, biology and ecology) or habitat level (e.g. species assemblages and species list) account for 24% to 33% of the information considered.

- From 30% to 46.2% of the activities analysed provide assessments at single stock level or management suggestions.

- A small proportion of the information gathered (6% at most, according to the basin considered) is related to modelling from both the ecological and the bio-economic point of view.

In spite of the large amount, the information reviewed was highly heterogeneous, making it difficult to draw a picture on how the EAF issues are addressed in each country. This heterogeneity is mainly due to the following reasons:

- Different types of projects/initiatives considered.

- Differences in the “interpretation” of the available information in the EAF context.

- The different nature of the partners (universities, national research institutions, governmental institutions, private research institutions, etc.).

Therefore an effort to harmonize and evaluate all the information available under the EAF point of view was deemed essential and it was carried out during the specific CREAM workshop held in May 2012. After the discussions and the standardized work performed during the workshop, an overview based on the expert evaluations was produced. Table 5 shows in detail the results obtained, according to a semi-quantitative score system. The scores were also summarized following the main EAF issues and presented according to radar graphs (Figs 2 and 3).

The results highlighted an overall low-medium degree of fulfilment of the requirements of the EAF in the Mediterranean and Black Seas, with some differences related to the different issues considered.

In general, the highest scores were reported for the knowledge related to fleet structure/behaviour (average score = 2) and species/habitat characteristics (average score = 1.5), while the lowest ones were reported for modelling, socio-economic and management issues (average score = 0.1). No substantial differences were detected according to the main basins considered.

DISCUSSIONTop

The most important finding of this work is that the EAF in the Mediterranean has much work to do. Although only semi-quantitative, the current results could provide an initial global picture at a wide geographical level to properly address the implementation of the EAF in the Mediterranean and Black Seas. Essentially, this exercise helped identify which aspects of EAF need to be reinforced by future research programmes and training actions. Our results show that knowledge on fisheries characterization, stocks and habitats is relatively high. On the other hand, information on the management process and socio-economic aspects of fisheries is relatively poor. The sustainable exploitation of marine living resources (including fisheries) and conservation of natural resources has been a top priority on the agenda of international organizations and States during the last two decades (for instance UNEP/MAP 2012UNEP/MAP 2012. State of the Mediterranean marine and coastal environment. Mediterranean Action Plan, Athens, 96 pp., United Nations 2002United Nations 2002. Plan of Implementation of the World Summit on Sustainable Development. Retrieved from http://www.un.org/esa/sustdev/documents/WSSD_POI_PD/English/WSSD_PlanImpl.pdf (accessed November 2013).), and the over-exploitation of stocks and impact of fishing activities on the environment has led to widespread demands for sustainable and responsible exploitation of stocks (for instance, the Marine Strategy Framework Directive 2008, COM 2012 for the EU countries, Black Sea Commission 2008Black Sea Commission 2008. Black sea transboundary diagnostic analysis. Black Sea Commission, Brando, V. E., Ceccarelli, R., Libralato, S., Ravagnan, G. 2004. Assessment of environmental management effects in a shallow water basin using mass-balance models. Ecol. Modell. 172(2-4): 213-232. for the Black Sea), but these priorities will not be effectively addressed with unbalanced knowledge among the different disciplines that hinders the effective application of the EAF. Management of fishery stocks is often complex and difficult, and this situation is exacerbated in the case of the Mediterranean and Black Sea fisheries with highly migratory, straddling and cross-border stocks. Data for the assessment and management of such stocks are gathered by different countries and supported by the European Commission and Regional Fisheries Management Organizations (RFMOs), such as the GFCM and the International Commission for the Conservation of Atlantic Tunas (ICCAT). However, due to the complexity of addressing research and management of shared stocks, coordinated efforts to develop scientific knowledge between the RFMOs and coastal States have not always been made. This has also been the case in both the Mediterranean and Black Seas, where the management of available marine biological resources is fragmented. Evidently, there has been a need to move towards a wider geographic and regional management of fisheries. To this end, the CREAM Concerted Action advanced cooperative research and can be regarded as an important step towards effective management of stocks exploited by various countries.

With few exceptions, current advice on the exploitation of fish stocks in the Mediterranean Sea is based on single-species assessments, whereas there is a pressing need for more ecosystem-oriented fisheries management and integration of ecosystem and socio-economic considerations into assessment procedures (Coll et al. 2013Coll M., Cury P., Azzurro E., Bariche M., Bayadas G., Bellido J.M., Chaboud C., Claudet J., El-Sayed A.F., Gascuel D., Knittweis L., Pipitone C., Samuel-Rhoads Y., Taleb S., Tudela S., Valls A. 2013. The scientific strategy needed to promote a regional ecosystem-based approach to fisheries in the Mediterranean and Black Seas. Rev. Fish Biol. Fish.). In the Mediterranean and Black Seas, existing national fisheries research agencies and international bodies related to management (GFCM, ICCAT, EU, BSC, RAC/SPA, FAO) have conducted, jointly or individually, a considerable amount of research on fisheries assessment and management that is conducive to the application of the EAF in both regions.

The CREAM Coordination and Support Action set up the basis for a network of research organizations by establishing a participatory dialogue between researchers and assessment and management bodies in order to define the research needs for implementing an EAF in the Mediterranean and Black Seas and provide scientific advice. To this end, the CREAM project claims that the EAF aims “to balance diverse societal objectives, by taking into account the knowledge and uncertainties about biotic, abiotic and human components of ecosystems and their interactions and applying an integrated approach to fisheries within ecologically meaningful boundaries” (FAO 2003FAO 2003. The ecosystem approach to fisheries. FAO Technical Guidelines for Responsible Fisheries, No. 4 (Suppl. 2). FAO Fisheries Department. Rome, FAO, 112 p.).

ACKNOWLEDGEMENTSTop

We thank the CREAM Partners for providing the data used for the analyses: Marina Panayotova (IO-BAS, Bulgaria); Vjekoslav Tičina (IOF, Croatia); Yianna Samuel-Rhoads (DFMR-MANRE, Nicosia, Cyprus); Abdel-Fattah El-Sayed, (Alexandria University, Egypt); Marta Coll (IRD & IFREMER, France); Joël Vigneau (IFREMER, France); Guranda Makharadze (WEFRI, Georgia); Germana Garofalo (CNR, Italy); Michel Bariche (American University of Beirut, Lebanon); Leyla Knittweis (MRRA, Malta); Abdelaziz Zoubai (INRH, Morocco); Gheorghe Radu (NIMRD, Romania); Dmitry Vasilyev (VNIRO, Russia) Federico Alvarez (IEO, Spain); Jordi Lleonart (ICM-CSIC, Spain); Skander Ben Salem (INSTM, Tunisia); Adnan Tokaç (Ege University, Turkey), Boris Trotsenko (YugNIRO, Ukraine).

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