Comparative Study on Parasite Fauna of the Whiting Merlangius merlangus in the Northern and Southern Zones of the Black Sea

The comparative parasite fauna of the whiting Merlangius merlangus (Linnaeus, 1758) in the Black Sea was determined using samples collected from the southern zone of the Sea near Sinop, Turkey and from the northern zone in Balaklava Bay, Sevastopol, Russia. The parasitological survey was conducted monthly between May 2011 and April 2014 on 690 fish from Sinop and 423 fish from Sevastopol. A total nine parasite species were identified which eight of were found at both sampling localities. Trichodina gobii Raabe, 1959, Eimeria merlangi Zaika, 1966, Ceratomyxa merlangi Zaika, 1966, Myxidium gadi Georgevitsch, 1916, Gyrodactylus alviga Dmitrieva and Gerasev, 1997, Hysterothylacium aduncum (Rudolphi, 1802) larvae and adults, Scolex pleuronectis Muller, 1788 plerocercoids and Grillotia erinaceus (van Beneden, 1858) plerocerci were recorded from both sampling localities whereas Prodistomum polonii (Molin, 1859) Bray and Gibson, 1990 was found only once in the Sevastopol samples. This study revealed considerable differences in the prevalence and abundance values of T. gobii, Gy. alviga, Gr. erinaceus and H. aduncum between the two regions indicating two distinct groups of whiting thus supporting other studies suggesting a complex structure of whiting stocks in the Black Sea.