“Their populations increase rapidly in these rivers, and as they feed themselves with the eggs of the other fishes, the other species are under threat,” said Nazmi Polat, an academic from Ondokuz Mayıs University in the Black Sea province of Samsun.
“These types of carps are called invasive species. Unfortunately, they have become the dominant species in both rivers,” added Polat.
The fish is also not preferred by the trollers as it is too bony and not tasty like salmon and catfish.
“I used to angle and catch seabass here in Kızılırmak, now all we can get is these crucian carps. It is unbeatable, so we give them to our animals,” said Efe Yıldız, an angler in Samsun who has been catching fishes for a long time.
“The fishermen are deeply grieved due to the crucian carps. They do not permit other species to live,” noted İbrahim Yıldız, another troller.
Kızılırmak, also known as the Halys River, is the longest river entirely in Turkey. Rising in eastern Anatolia, the river flows a total of 1,355 kilometers.
Hurriyet Daily News