Out of the four original species of fish in the Old Danube, only one is remaining. The reason is the amount of water in the old bed of the Danube and that it has become uninhabitable for many species of fish and the original species of fish may disappear, says LIFE Living Rivers project coordinator Bořek Drozd. Ichthyologist Filip Miklánek says that the Danube is still habitable for these species.
"Because the conditions have changed the problem is actually reproduction, and the overall occurrence of these original species is becoming smaller and smaller," said Miklánek.
However, the Old Danube is full of common carp fish, which, on the other hand, can multiply. Water quality can thus deteriorate. The fact that original species of fish are gradually disappearing from the Old Danube means that the river ecosystem is not working. According to experts, the situation would improve if more water flowed into the river and ecosystem would thus restore naturally.
Source: STVR
