Field studies of seahorse population density, structure and habitat use in a semi-closed north-eastern Mediterranean marine area (Stratoni, north Aegean Sea)

The present study was carried out in the marine area of Stratoni, Greece, where two seahorse species are present (Hippocampus hippocampus and H. guttulatus). Two surveys were conducted (September 2016, May 2019) to gather information regarding seahorse species’ abundance, distribution and habitat characteristics. Four different seahorse natural and artificial habitat types were identified. Results revealed that the abundance of H. hippocampus was relatively high, especially at sites with artificial structures, while the presence of H. guttulatus was rare. Data collected can provide baseline information for future population assessments.Project Seahorse. This work was supported by Hellas Gold (https://www.hellas-gold.com/). FCT - Foundation for Science and Technology through project UIDB/04326/2020, and from the operational programmes CRESC Algarve 2020 and COMPETE 2020 through project EMBRC.PT ALG-01-0145-FEDER-022121info:eu-repo/semantics/acceptedVersio

Mysida and Lophogastrida of Greece: a preliminary checklist

Abstract Backgroun

Polytraits : a database on biological traits of marine polychaetes

The study of ecosystem functioning – the role which organisms play in an ecosystem – is becoming increasingly important in marine ecological research. The functional structure of a community can be represented by a set of functional traits assigned to behavioural, reproductive and morphological characteristics. The collection of these traits from the literature is however a laborious and time-consuming process, and gaps of knowledge and restricted availability of literature are a common problem. Trait data are not yet readily being shared by research communities, and even if they are, a lack of trait data repositories and standards for data formats leads to the publication of trait information in forms which cannot be processed by computers. This paper describes Polytraits (http://polytraits.lifewatchgreece.eu), a database on biological traits of marine polychaetes (bristle worms, Polychaeta: Annelida). At present, the database contains almost 20,000 records on morphological, behavioural and reproductive characteristics of more than 1,000 marine polychaete species, all referenced by literature sources. All data can be freely accessed through the project website in different ways and formats, both human-readable and machine-readable, and have been submitted to the Encyclopedia of Life for archival and integration with trait information from other sources

Isotopic Niche and Trophic Position of the Invasive Portunid Portunus segnis Forskål, (1775) in Elounda Bay (Crete Island, Eastern Mediterranean)

There is a growing recognition that an advanced understanding of the trophic characteristics of an invasive consumer can provide important information on its ecological impact. In recent years, the blue swimming crab Portunus segnis, one of the earliest Lessepsian invaders, has considerably expanded its distribution range in the Mediterranean Sea, yet, its trophic habits in invaded areas remain scarcely investigated. In this study, we used carbon and nitrogen stable isotopes analysis (SIA) to determine the trophic position and isotopic niche of the crab compared with other representatives of the flora and fauna occurring in Elounda Bay (Crete). P. segnis showed a trophic position of 3.9, higher than the values determined by SIA or conventional gut content analysis in other areas of the Mediterranean Sea or in the native range. Crab specimens showed a high inter-individual variability in both delta C-13 and delta N-15 values; further analysis indicated negligible differences in the isotopic niche of adult males and females. Conversely, delta N-15 values were significantly related to the size of the specimens, ultimately suggesting an ontogenetic dietary shift. This study represents the first attempt to characterize the trophic habits of the blue swimming crab in the context of an invaded food web and may contribute to the implementation of long-term management strategies of control and mitigation of its ecological impact

Evaluating Ocean Literacy of Elementary School Students: Preliminary Results of a Cross-Cultural Study in the Mediterranean Region

A good understanding of the role and function of the ocean seems to be of paramount importance in recent years, constituting the basic tool for the promotion of healthy and sustainable marine environment, and a target area of the 2030 Agenda for Sustainable Development. In this study, the content knowledge of elementary school students (grades 3–6) in regards to ocean sciences issues was examined. A structured questionnaire was administered to 1004 students participating in a cross-cultural study from three Mediterranean countries (Italy, Croatia, and Greece). The results of the study indicated a rather moderate level of knowledge in the total sample, while slight differences were recorded among the three countries revealing common knowledge gains and misconceptions. Rasch analysis was applied to further evaluate the validity of the results, while the influence of certain demographics on students' knowledge level was also investigated. This study concludes with a discussion of the implications on national curriculum development in elementary education level, in order to promote ocean literacy and to ensure protection and conservation of the Mediterranean Sea

Early Succession Patterns of Benthic Assemblages on Artificial Reefs in the Oligotrophic Eastern Mediterranean Basin

The colonization of artificial structures by benthic organisms in the marine realm is known to be affected by the general trophic patterns of the biogeographical zone and the prevailing environmental traits at the local scale. The present work aims to present quantitative data on the early settlement progress of macrofaunal benthic assemblages developing on artificial reefs (ARs) deployed at the Underwater Biotechnological Park of Crete (UBPC) in the oligotrophic Eastern Mediterranean. Visual census and subsequent image analysis combined with scraped quadrats were used to describe the establishment of the communities and their development over three consecutive campaigns, span-ning 5 years post-deployment. Macroalgae consistently dominated in terms of coverage, while sessile invertebrates displayed different patterns over the years. Polychaeta and Bryozoa were gradually replaced by Cnidaria, while Porifera and Mollusca displayed an increasing trend over the years. Motile benthos was mainly represented by Mollusca, while the abundance of Polychaeta increased in contrast to that of Crustacea. For both sessile and motile assemblages, significant differences were observed among the years. The results of this study indicate that ecological succession is still ongoing, and further improvement in the monitoring methodology can assist towards a more accurate assessment of the community composition in complex AR structures.European Union MIS 5002670, MIS 502740

Mediterranean Sea Literacy: When Ocean Literacy becomes region-specific

Ocean Literacy (OL) has been defined as an understanding of the ocean’s influence on people and their influence on the ocean. The OL movement was born in the US and its framework consisted of seven essential principles and 45 fundamental concepts; it is now largely accepted worldwide for use in both formal (schools and universities) and non-formal (research institutes, aquaria, museums, etc.) education settings. Based on this framework, marine scientists and educators developed the “Mediterranean Sea Literacy” (MSL) guide adapted to the specificities of the Mediterranean region, presented here. The MSL principles (7) and concepts (43), serving as guidance for research, education, informed decision-making, and improved citizens’ lifestyles, aim to contribute to environmental protection, conservation, and restoration of the Mediterranean Sea as well as to help to achieve a blue innovative and sustainable economy

A Pilot Survey Investigating Naturoid Reefs as a Tool for Sustainable Marine Ecotourism

Recreational SCUBA diving is currently a nature-based USD multibillion tourism industry across the globe. However, degradation of many recreational diving destinations all over the world due to “soft” ecotourists necessitates the adoption of innovative management measures. Hellenic Centre for Marine Research (HCMR) developed an innovative technology for the creation of artificial underwater ecotourism attractions (“oases”) to divert visitors away from sensitive marine natural areas of high ecological and aesthetic value. This innovative technology includes specially constructed artificial reefs in an attempt to simulate the functional and morphological characteristics and the aesthetics of the natural rocky reefs. In this study, a pilot survey was conducted in three diving centres of Crete Island, one of the most important tourist destinations in the Mediterranean Sea, involving the participation of 144 SCUBA divers from all over the world. The survey aimed at investigating SCUBA divers’ profiles and perceptions concerning recreational diving activities and artificial reefs technology. Findings of this study indicate that large naval shipwrecks combined with innovative man-fabricated constructions simulating natural rocky reefs meet the preferences of the majority of the participants of the survey and they can be used as an alternative tool for relevant marine ecotourism sustainable applications

Cumacea of Greece: a preliminary checklist

The first attempt to compile the checklist of Cumacea of Greece was made in the context of the "Greek Biodiversity Database" project (2005-2008) coordinated by the Aristotle University of Thessaloniki. Since then, only scattered information on new elements of the Greek cumacean fauna has been available. The objectives of the present study were to update and cross-check taxonomically all cumacean species records from Greek waters for inaccuracies and omissions according to the recent literature and current taxonomic status. The updated checklist of Cumacea of Greece, which was built within the framework of the LifeWatch Greece Research Infrastructure (ESFRI) project (2013-2015) coordinated by the Hellenic Centre for Marine Research, comprises 62 species, classified in 24 genera and 6 families. However, a few more records need further cross-checking with the current literature resources