As the waters of the Gulf are relatively shallow with an average at about 35 metres, it can be assumed that prior to 14, 000 years ago this now submerged area was an open landscape with a supply of freshwater from Euphrates and Tigris.
But recently the inland waterways, docks and fresh-water intakes of North America have been overrun by zebra and quagga mussels species that originate from the area around the Black Sea.