A natural population of the European flat oyster (Ostrea edulis Linnaeus, 1758) in the northern Adriatic Sea: Changes over time and restoration potential
Published:
May 22, 2026
Keywords:
Ostrea edulis European flat oyster Adriatic Sea Population status Subtidal habitat Conservation ecology Oyster beds Biomass indices
Abstract
The European flat oyster (Ostrea edulis Linnaeus, 1758) is a native bivalve of high ecological and economic importance in European marine ecosystems. Overexploitation, combined with widespread disease outbreaks in the 1970s, has caused a severe decline throughout its historical range, leaving many populations critically depleted or functionally extinct. This study assesses the status of remnant natural O. edulis populations inhabiting deeper subtidal habitats (~30 m depth) in the northern Adriatic Sea, a region where O. edulis was abundant until relatively recently but has shown a pronounced decline over the last decade. We combined an extensive literature review with field surveys using beam trawl sampling and observations from a remotely operated vehicle (ROV). Analyses focused on oyster distribution, biomass indices, natural settlement substrates, and associated macrobenthic communities. Our results indicate a substantial decline in O. edulis biomass over the past decade, although small remnant populations persist within the study area. ROV surveys conducted at sites where fishing pressure has been eliminated, including historically abundant grounds, reveal no clear signs of population recovery. These findings suggest that reduced fishing pressure alone is insufficient to restore O. edulis populations. The results highlight the need for coordinated, region-wide monitoring and emphasise the importance of habitat availability, recruitment dynamics, and interactions with local aquaculture practices when developing effective conservation and restoration strategies for O. edulis in the Adriatic Sea.
Article Details
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EZGETA-BALIĆ, D., CVITANIĆ, R., VRGOČ, N., MEDVEŠEK, D., NEJAŠMIĆ, J., PEHARDA, M., ZORICA, B., STAGLIČIĆ, N., & BUJAS , N. (2026). A natural population of the European flat oyster (Ostrea edulis Linnaeus, 1758) in the northern Adriatic Sea: Changes over time and restoration potential. Mediterranean Marine Science, 27(2), 308–320. https://doi.org/10.12681/mms.43857
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