1063-0740/04/3002- © 2004
Russian Journal of Marine Biology, Vol. 30, No. 2, 2004, pp. 87–95.
Original Russian Text Copyright © 2004 by Biologiya Morya, Kas’yan.
Copepods usually make up the bulk of zooplankton,
but their abundance indices are different in different
seasons. Some information has already been published
about the occurrence of
, species characteristic of the Russian Far Eastern
seas and the adjacent waters of the Northwestern
Paciﬁc and the neritic genus
, for certain
bays of the Sea of Japan, the Inland Sea of Japan [3, 16,
17, 19], and some areas of Amursky Bay (Peter the
Great Bay, Sea of Japan) [4–10, 12–15,
copepod species may constitute a signiﬁcant proportion
in the diet of larvae and the young of some ﬁsh species
[2, 11, 21, 22]. In this paper we present original results
of comprehensive studies on the distribution and den-
sity dynamics of the copepods
in Amursky Bay.
The goal of this project was to study spatial–tempo-
ral variability in the population density and age struc-
ture of the copepods
in Amursky Bay, Sea of Japan, in the spring–autumn
period of 1991.
MATERIALS AND METHODS
For this study we used plankton samples collected by
colleagues from the Institute of Marine Biology, Far East
Branch, Russian Academy of Sciences in the months
May–November 1991, at 32 stations located in Amursky
Bay, Sea of Japan (Fig. 1). The samples were collected
with a modiﬁed “Norpak” plankton net (with ring diam-
eter of 46 cm, no. 49 mesh), at intervals of 10–15 days.
In the shallow (down to 8 m deep) part of the bay the
samples were collected across the entire water column,
from bottom to surface; in deep-water areas they were
collected from down to 60 m deep. The water tempera-
ture and salinity were measured in the lower sampling
horizon and at the surface (Fig. 2). Altogether 284 sam-
ples were collected in the course of 10 surveys per-
formed along three transects: (1) the Eastern Transect
(Stations 1–6, 8, 10, 12, and 26–32) along the coasts of
Russkii and Rikorda islands and Murav’eva-Amurskogo
Peninsula; (2) the Central Transect (Stations 14, 25,
36) located in the deep-sea area; and (3) the Western
Transect (Stations 15–24) along the mainland coast.
The schedule of the surveys was as follows: 1st sur-
vey—May 17, 18, 25, 27, and 31; 2nd survey—June 6,
7, 11, and 12; 3rd survey—June 26–28 and July 2 and
4; 4th survey—July 8, 11, and 12; 5th survey—July 22,
30, 31 and August 1 and 8; 6th survey—August 12, 13,
and 16 and August 27 (only at Stations 5, 6, 8, 10, and
12); 7th survey—August 28 (only at Stations 27–32)
and September 4, 6, and 12; 8th survey—September 16,
17, and 19; 9th survey—October 1, 7, and 8; and 10th
survey—October 24, 29, and 31 and November 1 and 11.
In this study we considered only copepodid stages
and adults of
, naupliar instars could not be identiﬁed accurately
and therefore were registered as the total for all species
of Copepoda. The samples were treated using standard
techniques, with Bogorov’s chamber, an automatic
pipette, and light microscopes “MBS-10” and “MBI-11.”
Different stages of
were identiﬁed according available descriptions (
and Li and Fan, 1990, cited from ).
Distribution and Seasonal Dynamics of the Abundance
Thompson et Scott (Copepoda) in Amursky Bay, Sea of Japan
V. V. Kas’yan
Institute of Marine Biology, Far East Division, Russian Academy of Sciences, Vladivostok, 690041 Russia
Received October 10, 2003
—The distribution and seasonal dynamics of
in Amursky Bay (Sea of Japan) were studied from May through November 1991.
plankton from May through August and in November, with a peak density of more than 40000 specimens/m
in June, at a temperature of 15–18
occurred from late June through November, with a maxi-
mum total density of 6900 specimens/m
in August, at 23
C. During the observation period, the distribution of
species in the bay was irregular due to the hydrological regime and sanitary conditions of water.
C. abdominalis, C. tenuiremis
, distribution, seasonal dynamics, Amursky Bay,
Sea of Japan.