Preliminary study on cryptobenthic fish assemblages affected by the mucilage event in the northeastern Aegean Sea

Preliminary study on cryptobenthic fish assemblages affected by the mucilage event in the northeastern Aegean Sea

Cem Dalyan, Nur Bikem Kesici, Ferhat Yalgın

ORCID IDs: C.D. 0000-0002-7386-5641; N.B.K. 0000-0002-9636-1649; F.Y. 0000-0002-0027-5114

Division of Hydrobiology, Department of Biology, Faculty of Science, Istanbul University, Istanbul, TURKEY
Underwater Technologies, Bandirma Onyedi Eylül University, Bandırma, Balıkesir, TURKEY


Cryptobenthic fishes form a major component of coastal fish communities. Due to their site fidelity, life strategies and habitat preferences, they can be considered as indicator organisms which some changes in the coastal ecosystem can be detected. In this study, the effects of the mucilage event were studied through cryptobenthic fish assemblages in the North Aegean Sea between May and August of 2021. During 12 dives, a total of 166 individuals of 19 cryptobenthic fish species were observed belonging to the families Gobiidae (7 species), Blennidae (7), Gobiesocidae (2) and Tripterygiidae (3). Density of the cryptobenthic fish were estimated as 11.4 (ind. per hour) in May and June (while intense mucilage formation was observed in the area) and 17.8 (ind. per hour) in July and August. The overall result revealed that the effects of mucilage are destructive for the marine cryptobenthic fishes.

Keywords: Gobiidae, Blenniidae, North Aegean Sea, Gökçeada Island, Saros Bay

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