Figure1.Map showing lower portions of the Volga and Ural rivers, northern part of the Caspian Sea, and adjacent regions referred to in
text. Other river systems historically used by the three commercially important species of sturgeons (Husohuso,Acipenserstellatus,and
A.gueldenstaedtii) are labeled.
Harvest trends during the last 40 years
Prior to 1951, commercial sturgeon fishing concen-
tratedin the Caspian Sea (Korobochkina 1964). Fol-
lowing recommendations to concentrate harvest to
only the lower reaches of the Volga River (Derz-
havin 1947), a ban on sea harvest was instituted. The
only sturgeon taken in the Caspian Sea were as a
by-catch to other fishes. The introduction of plastic
nets in the late 1950s for harvest in the Caspian Sea
greatly increased in the number of young sturgeons
caught as by-catch. In 1957, of the total 2.6 million
sturgeons harvested in the northern Caspian Sea,
1.8 million were young sturgeons, and in 1959–1961,
the by-catch of young sturgeons reached 2-3 mil-
lion (Korobochkina 1964). From 1962 until 1991,
sturgeons were not harvested legally in the north-
ern part of the Caspian Sea.
For the last 35 years, natural and artificial repro-
duction contributed to the total commercial stur-geon stock in the Caspian Sea (Barannikova 1995).
Sturgeon population sizes also depend on the vol-
ume of harvest, the construction and operation of
dams, water consumption for irrigation and indus-
try, and impacts of pollution. All three commercial-
ly important species of sturgeons now have fewer
spawning fish migrating into the Volga and Ural riv-
ers than in the past. Russian and beluga sturgeons
no longer use the Kura, Terek and Sulak rivers, al-
though small runs of stellate sturgeons still enter in-
to the Terek and Sulak rivers to spawn.
The Volga River and its delta are the most impor-
tant areas in terms of commercial harvest. About
75% of the total sturgeon catch in the Caspian Sea
basin comes from this area, with Russian sturgeon
providing 60–70% of this total. Until recently, stel-
late sturgeon made up about 30% of the catch in the
Volga River. Beluga constituted 5.0–6.0% of the
catch. Between 1976 and 1981, Russian sturgeon
were taken about four times more frequently than