Caviar sturgeon from the Sea of Azov began reaching the tables of aristocratic and noble Byzantine Greeks in the 10th century, after the commencement of large-scale trading between the Byzantine Empire and Kievan Rus'. The main types of caviar are Beluga, Sterlet, Kaluga hybrid, American osetra, Ossetra, Siberian sturgeon and Sevruga. The rarest and costliest is from beluga sturgeon that swim in the Caspian Sea, which is bordered by Iran, Kazakhstan, Russia, Turkmenistan, and Azerbaijan. Wild caviar production was suspended in Russia between 2008 and 2011 to allow wild stocks to replenish. Azerbaijan and Iran also allow the fishing of sturgeon
USS Sterlet (SS-392) October and unleashed four torpedoes on small convoy. Results: four misses. Not to be denied, "Sterlet" made another approach on the convoy. This time, four of the six fish she launched scored. Three hit a large gasoline tanker, and the fourth plowed into a freighter. The tanker, "Jinei Maru", is known definitely to have gone down. "Sterlet" spent the remainder of the day evading the attacks of the escorts. That night, she allowed a hospital ship to pass unmolested. She attacked a small freighter with four torpedoes on 29 October, but had to surface and sink it with her deck