ORIGINAL RESEARCH published: 17 November 2017 doi: 10.3389/fmars.2017.00347 Assembling Ecological Pieces to Reconstruct the Conservation Puzzle of the Aegean Sea Maria Sini 1*, Stelios Katsanevakis 1, Nikoleta Koukourouvli 2, Vasilis Gerovasileiou 1, 3, Thanos Dailianis 1, 3, Lene Buhl-Mortensen 4, Dimitris Damalas 5, Panagiotis Dendrinos 6, Xenophon Dimas 7, Alexandros Frantzis 8, Vasilis Gerakaris 9, Sylvaine Giakoumi 10, 11, Genoveva Gonzalez-Mirelis 4, Thomas Hasiotis 1, Yiannis Issaris 9, Stefanos G. Kavadas 5, David D. Koutsogiannopoulos 12, Drosos Koutsoubas 1, Evangelia Manoutsoglou 1, Vessa Markantonatou 1, Antonios D. Mazaris 13, Dimitris Poursanidis 1, 14, George Papatheodorou 7, Maria Salomidi 9, Konstantinos Topouzelis 1, Vasilis Trygonis 1, 5 1 Edited by: Vassiliki Vassilopoulou and Maria Zotou Tito Monteiro da Cruz Lotufo, 1 Department of Marine Sciences, University of the Aegean, Mytilene, Greece, 2 Department of Geography, University of the University of São Paulo, Brazil Aegean, Mytilene, Greece, 3 Institute of Marine Biological Resources and Inland Waters, Hellenic Center for Marine Research, Reviewed by: Heraklion, Greece, 4 Benthic Communities and Coastal Interactions, Institute of Marine Research, Bergen, Norway, 5 Institute Sergio Rossi, of Marine Biological Resources and Inland Waters, Hellenic Center for Marine Research, Athens, Greece, 6 MOm/Hellenic University of Salento, Italy Society for the Study and Protection of the Monk Seal, Athens, Greece, 7 Laboratory of Marine Geology and Physical Heliana Teixeira, Oceanography, Department of Geology, University of Patra, Patra, Greece, 8 Pelagos Cetacean Research Institute, Athens, University of Aveiro, Portugal Greece, 9 Institute of Oceanography, Hellenic Center for Marine Research, Athens, Greece, 10 Université Côte d’Azur, Centre 11 *Correspondence: National de la Recherche Scientifique, Nice, France, ARC Centre of Excellence for Environmental Decisions, School of 12 13 Maria Sini Biological Sciences, University of Queensland, Brisbane, QLD, Australia, Naturagraeca, Athens, Greece, Department of 14 [email protected] Ecology, School of Biology, Aristotle University of Thessaloniki, Thessaloniki, Greece, Institute of Applied and Computational Mathematics, Foundation for Research and Technology Hellas, Heraklion, Greece Specialty section: This article was submitted to The effective conservation of marine biodiversity through an integrated ecosystem-based Marine Evolutionary Biology, Biogeography and Species Diversity, management approach requires a sound knowledge of the spatial distribution of a section of the journal habitats and species. Although costly in terms of time and resources, acquiring such Frontiers in Marine Science information is essential for the development of rigorous management plans and the Received: 12 July 2017 meaningful prioritization of conservation actions. Located in the northeastern part of the Accepted: 16 October 2017 Published: 17 November 2017 Mediterranean, the Aegean Sea represents a stronghold for marine biodiversity. However, Citation: conservation efforts are hampered by the apparent lack of spatial information regarding Sini M, Katsanevakis S, marine habitats and species. This work is the first to address this knowledge gap by Koukourouvli N, Gerovasileiou V, Dailianis T, Buhl-Mortensen L, assembling, updating, and mapping information on the distribution of key ecological Damalas D, Dendrinos P, Dimas X, components. A range of data sources and methodological approaches was utilized to Frantzis A, Gerakaris V, Giakoumi S, compile and complement the available data on 68 ecological features of conservation Gonzalez-Mirelis G, Hasiotis T, Issaris Y, Kavadas SG, interest (58 animal species, six habitat categories, and four other vulnerable ecological Koutsogiannopoulos DD, features). A standardized data evaluation procedure was applied, based on five Koutsoubas D, Manoutsoglou E, Markantonatou V, Mazaris AD, semi-quantitative data quality indicators in the form of a pedigree matrix. This approach Poursanidis D, Papatheodorou G, assessed the sufficiency of the datasets and allowed the identification of the main sources Salomidi M, Topouzelis K, Trygonis V, of uncertainty, highlighting aspects that require further investigation. The overall dataset Vassilopoulou V and Zotou M (2017) Assembling Ecological Pieces to was found to be sufficient in terms of reliability and spatiotemporal relevance. However, it Reconstruct the Conservation Puzzle lacked in completeness, showing that there are still large areas of the Aegean that remain of the Aegean Sea. Front. Mar. Sci. 4:347. understudied, while further research is needed to elucidate the distribution patterns doi: 10.3389/fmars.2017.00347 and conservation status of several ecological features; especially the less charismatic Frontiers in Marine Science | www.frontiersin.org 1 November 2017 | Volume 4 | Article 347 Sini et al. Aegean Sea Conservation Puzzle ones and those found in waters deeper than 40 m. Moreover, existing conservation measures appear to be inadequate to safeguard biodiversity. Only 2.3% of the study area corresponds to designated areas for conservation, while 41 of the ecological features are underrepresented in these areas. Considering the high geomorphological complexity and transnational character of the Aegean Sea, this study does not offer a complete account of the multifaceted diversity of this ecoregion. Instead, it represents a significant starting point and a solid basis for the development of systematic conservation plans that will allow the effective protection of biodiversity within an adaptive management framework. Keywords: ecological mapping, marine biodiversity distribution, spatial information, data evaluation, conservation planning, ecosystem-based management INTRODUCTION (Fraschetti et al., 2008; UNEP/MAP-RAC/SPA, 2015b). It is also one of the most heavily impacted regions of the world, mainly The ongoing deterioration of marine ecosystems and the due to historical and current overfishing, coastal development, subsequent decrease of biodiversity due to the cumulative pollution, climate change, and invasive species (Halpern et al., impacts of anthropogenic pressures, alongside the ever- 2008; Coll et al., 2011; Micheli et al., 2013a). To date, a total increasing demand for marine space and natural resources, of 1,231 marine sites of variable protection level have been highlight the need for an integrated approach towards ecosystem- identified in the Mediterranean Sea, corresponding to 7.14% based management. In an effort to halt biodiversity loss at a of its total surface area (MedPAN and UNEP/MAP-SPA/RAC, global scale, the Aichi Target 11 of the Convention on Biological 2016). Although existing well-enforced Mediterranean MPAs Diversity (CBD) dictates that 10% of the sea should be protected are effective at local scales (Giakoumi et al., 2017), they fail by 2020. This is to be achieved through the establishment of to accommodate the conservation of biodiversity at a regional “effectively and equitably managed, ecologically representative scale through a unified approach (Giakoumi et al., 2012a). The and well-connected systems of protected areas and other majority of MPAs have been declared as such in an unsystematic effective area-based conservation measures” (Aichi Target 11, manner, i.e., not following a common set of selection criteria CBD). To this end, systematic conservation planning and and with little or no quantitative information to guide their marine spatial planning are currently considered as valuable designation (Giakoumi et al., 2011). Moreover, most of the MPAs tools to compensate the inadequacies of traditional sectoral are found in the western basin; in the rest of the Mediterranean, management approaches (Possingham et al., 2006; Katsanevakis more than half of the sites have no administrative body or et al., 2011b). Spatial prioritization is essential when planning for management plans (PISCO and UNS, 2016). As a result, a large conservation purposes, as it allows for the meaningful allocation part of the Mediterranean biodiversity is underrepresented in of limited resources to specific management actions within well- existing environmental management schemes, and remains defined areas, in a way that is most likely to produce effective effectively unprotected (MedPAN and UNEP/MAP-SPA/RAC, conservation outcomes (Moilanen et al., 2009). At the same 2016; PISCO and UNS, 2016). This is especially true for time, systematic conservation planning identifies priority areas the southern and eastern parts of the basin (including the for the establishment of Marine Protected Areas (MPAs), whilst Alboran, Eastern Ionian, Levantine, and Aegean seas), where reducing potential conflicts between conservation and socio- a considerable lack of spatial information regarding ecological economic objectives. This way, it maximizes the chances for the features, alongside several geopolitical and socio-economic successful application of management measures (Margules and factors, have dramatically delayed the implementation of rigid Pressey, 2000; Possingham et al., 2006). To achieve conservation conservation actions (Giakoumi et al., 2012b; Katsanevakis et al., targets however, this approach requires good knowledge of the 2015). spatial distribution of all major ecological and socio-economic The need to improve the effectiveness of conservation actions, components found within the areas of interest (Lourie and both at a regional and at a local scale,