The Mediterranean fan mussel Pinna nobilis is suffering a mass mortality event that started in 2016 in the Western Mediterranean and that has meanwhile spread throughout de Mediterranean Sea.

This study presents the results of the first broad-scale assessment of the spatial distribution of P. nobilis population in the Gulf of Erdek (Sea of Marmara, Turkey), based on underwater surveys.

A total of 2164 mussels were counted, of which 78.8% were alive, the mean density was around 18 individuals/100 m2, and recorded densities reached 71.2 individuals/100m2 among the studied sites. Results also show that 57% of the population was constituted of juveniles.

The authors highlight that despite many deaths to uncertain causes, the obtained results indicate a partially promising scenario for the fan mussel population in the Gulf of Erdek and highlight the existence of many alive juveniles that could play a primary role in the sustainability of the population. The authors also stress that this situation is not static and that anthropogenic changes and human activities could affect population welfare in the future.

It is concluded that these high-density sites need to be protected, and protection measures in these locations should include all effects that may cause incidental mortality.

Karadurmuş &Sari (2022) The last hope: the struggle for survival of fan mussels in the Gulf of Erdek, Sea of Marmara, Turkey. Mediterranean Marine Science 23:473-483.