Black-caviar-producing sturgeon becoming extinct in Caspian Sea MOSCOW, Dec. 28 (UPI) -- Russia and other countries that border the Caspian Sea have banned the fishing of black-caviar-producing sturgeon in the region for one year, officials say. The ban will go into effect Jan. 1 for at least one year, but it could be extended for up to five years, RIA Novosti reported. Kazakhstan, Iran, Azerbaijan and Turkmenistan also agreed to the ban. Russian officials said Friday the ban is being put in place because sturgeons, which are sold internationally for about $2.50 a gram, are becoming extinct.