1063-0740/04/3006- © 2004
Russian Journal of Marine Biology, Vol. 30, No. 6, 2004, pp. 421–425.
Original Russian Text Copyright © 2004 by Biologiya Morya, Ovsyannikov.
A certain size of eggs is characteristic for different
species and subspecies of ﬁshes [10, 12], the size of
eggs in any one species being increasable from the
southern to northern parts of the area . This law for
walleye pollack was revealed by Gorbunova ,
according to her data walleye pollack eggs in the
spawning areas of the Bering Sea and the Sea of
Okhotsk are larger (average size from 1.48 up to
1.66 mm) than in the spawning areas of the Sea of
Japan (average size from 1.41 up to 1.55 mm). How-
ever, N.N. Gorbunova’s research does not cover all the
reproduction areas of walleye pollack currently known.
It concerns the northern Sea of Okhotsk where the egg
size composition of walleye pollack is investigated only
on the western coast of Kamchatka. Studies carried out
at the end of the 1970s and 1980s [1, 2, 9, 14, 15, 16]
showed that in the northern Sea of Okhotsk the places
of egg concentration and the corresponding walleye
pollack spawning areas were situated not only along all
the coast of Kamchatka, but in Shelikhov Bay, in the
Pritaujskii district, on Lebedya hill, in the Iona Island
area, and on eastern Sakhalin. We failed to ﬁnd new
data on the egg sizes of walleye pollack in the northern
Sea of Okhotsk in references. Based on this fact, the
purpose of this work is to study the egg size composi-
tion of walleye pollack in spawning areas of the north-
ern Sea of Okhotsk.
MATERIALS AND METHODS
The data of a standard ichthyoplanctonic survey
which was conducted by the Laboratory of walleye pol-
lack of the TINRO-center in the northern Sea of
Okhotsk in 2001 on RV “TINRO” were used in this
paper. Samples were collected with the IKS-80 ichthy-
The Size Composition of the Pelagic Eggs
of Walleye Pollack
in Spawning Areas
of the Northern Sea of Okhotsk
E. E. Ovsyannikov
Paciﬁc Fisheries Research Center,
Vladivostok, 690950 Russia
Received November 10, 2003
—The data on the size composition of the pollack developing eggs of walleye pollack collected in the
northern Sea of Okhotsk in 2001 during mass spawning are given. The eggs caught in western Kamchatka and
in Shelikhov Bay had the greatest diameter; they were somewhat less in the northern Okhotsk Sea area; and the
smallest eggs were found in eastern Sakhalin. The clinal variability of the size composition of walleye pollack
eggs was observed in the northern Sea of Okhotsk, and in the western and eastern parts it had a local pattern.
Parameters such as spawning female size composition, temperature, and salinity, as well their inﬂuence on the
size composition of eggs, were considered.
northern Sea of Okhotsk, walleye pollack, eggs, sizes, variability.
Frequency of occurrence of walleye pollack eggs at
developmental stages I–IV in the northern Sea of Okhotsk
Frequency of occurrence Maximal num-
ber of eggs
per 1 m
I II III IV
ZK 91.6 8.0 0.5 0 7550
ZS 79.4 20.3 0.4 0 1708
SOH 47.7 41.5 10.4 0.4 1804
VS 69.6 22.8 6.9 1 768
* See the text for the designations of the areas here and in Tables 2–4.
The ratio of sex products at maturity stages II–V in
pubescent females of walleye Pollack in the northern Sea of
III III–IV IV IV–V V VI–II
ZK 1.2 0.2 28.8 39.6 15.6 14.6 2484
ZS 0 0 12.0 39.4 21.8 26.8 1257
SOH 0.3 0.4 12.0 42.9 15.6 28.8 3357
VS 0.1 1.0 15.4 12.7 4.0 66.8 1080
* The number of specimens examined.