Danube sturgeons—whose roe is prized as a source of caviar—have become so critically endangered that caviar exports from natural fish populations (as opposed to farmed fish) from all Lower Danube countries have been banned by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). Bulgaria, however, has granted the fish a temporary reprieve by enacting a one-year ban on sturgeon fishing along its section of the Danube—complementing a 10-year ban imposed five years ago by Romania on the opposite bank. These countries share almost a third of the Danube's length, giving the sturgeon a vast area in which to swim free from human grasp. Meanwhile, Azerbaijan, Turkmenistan, Kazakhstan, Iran and Russia have also imposed a 5–10 year ban on sturgeon fishing in the nearby Caspian Sea.