1063-0740/04/3004- © 2004
Russian Journal of Marine Biology, Vol. 30, No. 4, 2004, pp. 248–258.
Original Russian Text Copyright © 2004 by Biologiya Morya, Balanov, Zemnukhov, Ivanov.
Eelpouts (family Zoarcidae) are typical inhabitants
of the continental shelf and bathyal zone . Although
they play a key role in the bottom ichtyocenoses [7, 27],
most species of this family have scarcely been studied
in terms of their ecology [17, 29, 32, 34, 35].
was ﬁrst described
by Taranetz and Andriashev  and was originally
collected from the Sea of Okhotsk. Later, it was also
encountered in the Paciﬁc waters off the North Kuril
Islands and near Kamchatka, as well as in the Bering
Sea [19, 14] and in the Sea of Japan (Kato
cited from ). The greatest biomass and abundance of
were registered in the Sea of Okhotsk,
where it is one of the ﬁve most abundant bathyal ﬁsh
species . Although this species plays a key role in the
bathyal communities of the Sea of Okhotsk, data on its
distribution and biology are extremely scarce.
This study draws on an extensive body of data to
show the peculiarities of the distribution of the eelpout
over the continental slope of the Sea of
Okhotsk and thereby to give a detailed account of the
range of this species in the Northwest Paciﬁc Ocean.
MATERIALS AND METHODS
Most samples were collected during a series of four
cruises on the continental slope of the Sea of Okhotsk,
which were organized by the Paciﬁc Fisheries Research
Center. The following vessels were involved in the sur-
vey. The trawler
performed 33 hauls in
September and October 1984 (collector V.V. Fedorov);
performed 38 hauls during July
and August 1987; the trawler
254 hauls from May through September 1989 (collec-
tor V.N. Dolganov); and the research vessel
formed 110 hauls from August to October 1997 (collec-
tor O.A. Ivanov). The surveys covered almost the entire
area of the Sea of Okhotsk, except for the waters off the
South and Central Kuril Islands, where it was difﬁcult
to perform hauls because of the complex steep bottom
relief (Fig. 1). In all, specimens collected from
435 trawl stations at depths of 100–2063 m were exam-
ined (Table 1). For a more thorough survey, the Sea of
Okhotsk was divided into four sectors on the basis of
the data on where the eelpout was caught in the largest
and smallest numbers (Fig. 2).
The vessels involved in the survey used a standard-
ized bottom trawl rigged with a cookie gear. The verti-
cal and horizontal openings of the trawl were 7–10 and
29.5 m, respectively; both daytime and nighttime sam-
plings were conducted; each ﬁshing tow lasted 1 h.
In order to study the size composition of
, the total body length (TL) was measured from the
anterior tip of the body to the posterior end of the cau-
dal ﬁn. In total, 2458 individuals were examined.
Distribution of the Eelpout
over the Continental Slope of the Sea of Okhotsk
A. A. Balanov
, V. V. Zemnukhov
, and O. A. Ivanov
Institute of Marine Biology, Far East Division, Russian Academy of Sciences, Vladivostok, 690041 Russia
Paciﬁc Fisheries Research Center, Vladivostok, 690600 Russia
Received October 10, 2003
was found at depths of 153 to 1005 m in the Sea of Okhotsk; how-
ever, it usually inhabits the depth range of 400 to 800. The mean and maximum abundance and the biomass of
this species were 198.5 and 1037 individuals per km
and 173.7 and 1275 kg/km
, respectively. In view of the
data on the distribution of young ﬁsh (up to 30 cm in total body length) and the reports on the absence of
larvae, a hypothesis was developed that this species spawns predominantly in the waters off western
Kamchatka and eastern Sakhalin at the depth range of 700 to 900 m. Large individuals (>50 cm) exhibit higher
migratory activity and are more tolerant of environmental conditions. That is why they are encountered
throughout the distribution area of this species, even in subzero temperature areas.
be a typical inhabitant of the Sea of Okhotsk, except for the waters off the South and Central Kuril Islands and
the Paciﬁc waters off the North Kuril Islands.
, distribution, temperature, size composition, the Sea of Okhotsk.