Building a baseline for habitat-forming corals by a multi-source approach, including Web Ecological Knowledge

In the Mediterranean, habitat-forming corals often characterize essential fish habitats. While their distribution is sufficiently known for the western basin, few data are available from the Central-Eastern Mediterranean Sea (CEM). This study fills this gap supplying the largest dataset ever built on the geographical and bathymetric distribution of the most relevant habitat-forming corals (Eunicella cavolini, Eunicella verrucosa, Eunicella singularis, Leptogorgia sarmentosa, Paramuricea clavata, Corallium rubrum and Savalia savaglia) of the CEM. Information collected from different sources such as literature, citizen science, and from the World Wide Web (WWW) was combined. Videos published on the WWW provided additional information on the presence of fishing lines and signs of damage, as well as on the distribution of purple and yellow-purple colonies of Paramuricea clavata. The study highlighted the impressive amount of information that the WWW can offer to scientists, termed here as Web Ecological Knowledge (WEK). The WEK is constantly fuelled by internauts, representing a free, refreshable, long-term exploitable reservoir of information. A quick and easy method to retrieve data from the WWW was illustrated. In addition, the distribution of corals was overlapped to marine protected areas and to the distribution of environmental conditions suitable for coralligenous habitats, fragile biogenic Mediterranean structures hosting complex assemblages in need of strict protection. The collected data allowed identifying priority areas with high species diversity and sites that are impacted by fishing activities. Supplied data can correctly address conservation and restoration policies in the CEM, adding an important contribution to ecosystem-based marine spatial planning.This is a post-peer-review, pre-copyedit version of an article published in Biodiversity and Conservation on 23 December 2017 (First Online). The final authenticated version is available online at: https://doi.org/10.1007/s10531-017-1492-8 https://link.springer.com/article/10.1007%2Fs10531-017-1492-8 An embargo period of 12 months applies to this Journal. This paper has received funding from the European Union (EU)'s H2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 643712 to the project Green Bubbles RISE for sustainable diving (Green Bubbles). This paper reflects only the authors' view. The Research Executive Agency is not responsible for any use that may be made of the information it contains. © 2017. This manuscript version is made available under the CC-BY-NC-ND 4.0 Acknowledgements We are grateful to everyone who collaborated on this work by supplying information or photos, including Adelmo Sorci (Marlin Tremiti), Robert Horvat (Kornati Diving Center), Egidio Trainito, Franco Banfi, Dr. Giuseppe Piccioli Resta, Michalis Kanakakis, Vincenzo Fedele, Eric Šešelja, Marjan Makuc (Croatia Divers), and the staff of Scuba Diving Otranto, DWD Diving Diso (Lecce), Paxos Oasi Sub, Diving Center Zlatna Luka, Diving Center Ugljan, Pelagos Diving Lampedusa. The research was funded by the European Union Horizon 2020 research and innovation programme Green Bubbles RISE project, (H2020-MSCA-RISE-2014, Grant Agreement Number 643712), the MERCES Project (Marine Ecosystem Restoration in changing European Seas, Grant Agreement Number 689518), the AMER flag project (AMER 2013–2015; Adriatic Marine Ecosystem Recovery) and the PRIN projects (Progetti di Ricerca di Interesse Nazionale, http://prin.miur.it) (prot. 2008YBEANX_002) and "Coastal bioconstructions: structures, functions, and management" (prot. 2010Z8HJ5M)