From Wikipedia
Beluga caviar is
caviar consisting of the
roe(or eggs) of the
beluga sturgeon
Huso huso. It is found primarily in the
Caspian Sea, the world’s largest salt-water lake, which is bordered by
Iran and the
CIS countries of Azerbaijan, Kazakhstan, Russia, and Turkmenistan. It can also be found in the
Black Sea basin and occasionally in the
Adriatic Sea.