Stakeholder Mental Models for Sustainable Management of the Invasive Pearl Oyster Pinctada radiata in the Eastern Mediterranean

Abstract

Sustainable management of marine and coastal systems depends not only on ecological dynamics but also on the ways stakeholders perceive and interpret them. This study investigates how fishers, scientists, and government officials understand and frame the management of the Indo-Pacific pearl oyster Pinctada radiata, a non-native yet economically valuable species established around Evia Island, Greece. Using a mixed-methods approach (N = 80), we combined an eleven-item Hydro-ecological Governance Perception Scale (HGPS) with open-ended responses to explore cognitive patterns and governance perspectives. Sampling adequacy was satisfactory (KMO = 0.74; Bartlett’s χ²(55) = 350.41, p < 0.001) and factor analysis revealed two interrelated dimensions explaining 67.8% of total variance (α = 0.84; ω = 0.86; CR = 0.82). Although Kruskal-Wallis tests showed no statistically significant differences among groups (p > 0.05), hierarchical clustering distinguished three partially overlapping cognitive profiles: Ecological Pragmatists, Institutional Collaborators, and Adaptive Stewards (Silhouette = 0.45; CH = 150.23; DBI = 0.75). Thematic and sentiment analyses underscored the importance of collaboration, transparency, and education (mean sentiment = 0.58). The findings demonstrate how cognitive diversity can improve hydro-ecological resilience and the sustainability of coastal governance when it is mobilized through co-management and participatory monitoring.

Keywords

Hydro-ecological governance / Stakeholder cognition / Co-management / Cognitive diversity / Marine sustainability / Eastern Mediterranean

Statement of the Use of Generative AI and AI-Assisted Technologies in the Writing Process

During the preparation of this manuscript, the authors used Gemini (Google DeepMind) exclusively for language editing. After using this tool, the authors reviewed, revised, and approved all generated content and take full responsibility for the final version of the manuscript.

Acknowledgments

The authors would like to thank all participating fishers, scientists, and government officials from Evia Island for their valuable insights, collaboration, and contribution to this study.

Author Contributions

Conceptualization, D.P. and D.K.; Methodology, D.P.; Software, D.P.; Validation, D.P., A.C., A.T., D.V. and D.K.; Formal Analysis, D.P.; Investigation, D.P., A.C., A.T., D.V. and D.K.; Resources, D.P., A.C., A.T., D.V. and D.K.; Data Curation, D.P.; Writing—Original Draft Preparation, D.P.; Writing—Review & Editing, D.P., A.C., A.T., D.V. and D.K.; Visualization, D.P.; Supervision, D.K.; Project Administration, D.P. All authors have read and agreed to the published version of the manuscript.

Ethics Statement

The study was conducted in accordance with the ethical principles of the Hellenic National Commission for Bioethics and Technoethics (2020) and the EU General Data Protection Regulation (GDPR, Regulation EU 2016/679). Ethical review and approval were waived for this study, as no personal or sensitive data were collected.

Informed Consent Statement

Informed consent was obtained from all subjects involved in the study. Participation was voluntary, and all responses were anonymized in accordance with the Hellenic National Commission for Bioethics and Technoethics (2020) and the EU General Data Protection Regulation (GDPR, Regulation EU 2016/679).

Data Availability Statement

All datasets generated and analyzed during the current study are available from the corresponding author upon reasonable request.

Funding

This research received no external funding. The Article Processing Charge (APC) was waived by the publisher.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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