The chief are the Sardab-rud, Chalus, Herhaz (Lar in its upper course), Babul, Tejen and Nika, and all are well stocked with trout, salmon (azad-mahi), perch (safid-mahi), carp (kupur), bream (subulu), sturgeon (sag-mahi) and other fish, which with rice form the staple food of the inhabitants; the sturgeon supplies the caviare for the Russian market.
Fishing off the mouth of the Volga gives occupation to 50,000 persons; the fish, chiefly herrings and sturgeon, together with the caviare prepared from the latter, are sold for the most part at Nizhniy-Novgorod.
The coarse-grained grey Rumanian caviare is forwarded to Berlin, and there blended with Russian caviare.
This river supports a considerable fishing population, who despatch salt fish and caviare all over Russia.
The fish of greatest economic value are sturgeon (four species), which yield great quantities of caviare and isinglass, the herring, the salmon and the lobster.