1063-0740/04/3005- © 2004
Russian Journal of Marine Biology, Vol. 30, No. 5, 2004, pp. 298–305.
Original Russian Text Copyright © 2004 by Biologiya Morya, Gorbatenko, Lazhentsev, Loboda.
The Paciﬁc herring
Clupea harengus pallasi
of the basic commercial ﬁsh species in Russia. Studies
on its feeding have been carried out since the beginning
of the 1950s [1, 6, 7, 8, 9, 12, 15, 21, 22]. Signiﬁcant
data on the biology of the Paciﬁc herring and on the
conditions of its habitation have been accumulated as a
result of yearly integrated expeditions of the TINRO-
Center, which have been conducted in the Sea of
Okhotsk since 1984. The obtained information was
published in a series of papers considering the distribu-
tion, common features of biology, and the migration
patterns of the Paciﬁc herring [13, 14, 15, 16, 19, 26, 27].
In the works on herring feeding, the basic attention was
paid to the qualitative and quantitative composition of its
food in the summer–autumn season; the physiological
condition of the ﬁsh was not considered [11, 23, 24].
This paper presents results of spring studies on the
Okhotsk and Gizhigin-Kamchatka herring obtained
during the 1998–2002 expeditions of the TINRO-Center.
The primary attention was paid to estimate the condi-
tion of its forage base and to reveal the dependence
between feeding pattern in different size groups of her-
ring and some physiological parameters.
MATERIALS AND METHODS
This study is based on the material of ﬁve integrated
expeditions conducted in the northern Sea of Okhotsk
in the spring season of 1998–2002. The trophological
research was carried out using a standard procedure
adopted in the TINRO-Center [17, 20]. Samples of
25 ﬁsh each were taken from trawl catches to ana-
lyze the feeding of the herring. The stomach contents
were processed right after dissection, without prelimi-
nary ﬁxation in formalin, which allowed us to deter-
mine correctly the proportion of fresh food. The full-
ness of the stomach with food was registered using a 5-
grade scale, and then the stomach contents were
weighed. Wherever possible, we determined the weight
of each component of the food, the proportion of com-
mon species (% of the total weight of food pellet), the
degree of digestion (in a ﬁve-grade scale), and the total
and partial indexes of stomach fullness. The obtained
data were averaged for each biostatistical area 
(Fig. 1). Altogether 1333, 2418, 2216, and 3864 food
pellets from herring stomachs were examined in 1998,
1999, 2000, 2001, and 2002 respectively.
Kogan’s  technique was used to estimate the
daily rations. This technique was based on determina-
tion of the feeding rhythm and food consumption, tak-
ing into account the rate of digestion. In some instances
the ration was estimated as the average daily food con-
sumption determined by the quantity of fresh food .
The plankton was sampled with a BSD plankton net
(made of a 0.168 mm nylon mesh, with an aperture area
of 0.1 m
) in the layer of 0–200 m deep, or throughout
the bottom-surface column, if the depth was less than
200 m. The rate of net hoisting was 0.8–1.0 m/s. The
plankton samples were treated by fractions, according
to the technique adopted in the TINRO-Center [2, 3].
The numbers of small copepods, eggs and nauplii of
copepods and euphausiids, juveniles of
, and nauplii and larvae of bottom invertebrates were
counted with a Bogorov’s chamber. Large forms of
zooplankton were counted over the entire sample. The
catchability coefﬁcients generally used in TINRO,
Distribution, Feeding, and Some Physiological Parameters
of the Pacific Herring from the Gizhigin
and Okhotsk Populations in the North Part
of the Sea of Okhotsk in the Spring Season
K. M. Gorbatenko, A. E. Lazhentsev, and S. V. Loboda
Paciﬁc Fisheries Research Center (TINRO–Center), Vladivostok, 690950 Russia
Received March 11, 2004
—The distribution of the Paciﬁc herring of various sizes from the Okhotsk and Gizhigin-Kamchatka
populations is discussed. The dependence of herring food composition on the condition of the plankton com-
munity is demonstrated. In the spring season the feeding rate of juveniles and fattening adult herring depended
on the degree of its fatness and on the maturity of the gonads in the prespawning period.
Sea of Okhotsk, herring, stage of maturation, intensity of feeding, fatness.