ACTA ZOOLOGICA BULGARICA, cilt.74, sa.3, ss.445-453, 2022 (SCI-Expanded)
The Hersek Lagoon is a small lagoon located in the Marmara Sea. It is a breeding and feeding area for
many bird species, which makes it an internationally important wetland despite its small size. However, it
is under pressure due to the deterioration of the natural water regime and increasing pollution. Although
macroinvertebrates are important indicators in the environmental monitoring, no study has been conducted on the macroinvertebrate fauna of this lagoon. The present study was conducted to evaluate the
relationship between environmental parameters and benthic macroinvertebrates. Totally, 34 species were
identified in the lagoon, two of which (Hydroides dianthus (Verrill, 1873), Lekanesphaera monodi (Arcangeli, 1934)) are reported from the Sea of Marmara for the first time. Three alien species were detected
in the lagoon: Ruditapes philippinarum (A. Adams & Reeve, 1850), Polydora cornuta Bosc, 1802 and
Hydroides dianthus (Verrill, 1873). Diversity index values at all stations showed that macrobenthic fauna
is poor in terms of species diversity. Low levels of dissolved oxygen and the high total organic carbon
content throughout the lagoon sediment seem to negatively affect the benthic fauna, especially at stations
far from the open sea. The fact that the dominant species in the lagoon are resistant to organic pollution
also supports this view.