In the fish market at Istanbul, most of the fish coming off the trawlers is illegal - undersized. But the Turkish fishermen are desperate. They are like starving farmers eating their own seed corn. Decent fish are still available in Ukraine waters and a black market trade has started in Ukrainian Turbot - with some Turkish fishermen acting as middlemen. At the end of the road - death.
Many species are already extinct.
Others are in danger. Once the fish of the Black Sea fed the city states of Greece, the Roman empire, the Byzantines and the Ottomans.