1063-0740/03/2902- $25.00 © 2003
Russian Journal of Marine Biology, Vol. 29, No. 2, 2003, pp. 104–109.
Original Russian Text Copyright © 2003 by Biologiya Morya, Labai, Poltev, Mukhametov.
The biology of most ﬁshes occurring off the North-
ern Kuril Islands has been poorly studied except for
some commercial species, however, it is important for
understanding the functioning of the local ecosystem.
Liparidae), a mass species of the benthal ﬁsh commu-
nity of the continental slope area surveyed, has been
insufﬁciently studied despite the fact that it occurs in
abundance (up to 12%) in benthal trawling catches. Its
appearance strongly resembles that of
Kido 1983, which differs from
in a longer lower lobe of the
pectoral ﬁn. In Orlov’s recent paper ,
is referred to as
sp. and described
as a temperate–boreal mesobenthal ﬁsh occurring at a
depth of 118–646 m. Earlier, Tokranov provided a short
description of the feeding habits of liparid ﬁshes off the
Northern Kuril Islands . The feeding of
was described in greater detail in, respectively, ,
, and . The present paper concentrates on the
caught off the Northern
Kuril Islands in autumn 1997.
MATERIALS AND METHODS
The paper presents the results of the analysis of the
stomach contents of
caught in the
oceanic waters off the Northern Kuril Islands and
Southwestern Kamchatka (47|51(–51|27(N) at a depth
of 125–650 m during the voyage of the Japanese
trawler “Tomi-Maru no. 82” in September–October
1997. The trawlings were performed using a bottom
trawl with vertical and horizontal mouth openings of,
respectively, 6 and 18 m and a mesh size of 120 mm.
The trawling speed varied between 2.4 and 4.0 knots.
One to 12 snailﬁsh specimens were sampled from each
haul. The stomach contents were ﬁxed with 4% formal-
dehyde. The article dwells upon the results of the anal-
ysis of the stomach contents from 117
specimens found in 16 hauls. The results of the
analysis of 158
commercial statistical data obtained from 55 hauls con-
taining snailﬁsh were also used in the study. The stom-
achs, 21.5–38 cm long, were processed in a laboratory
using the weight method .
The food organisms were identiﬁed using the keys for
respective groups [4, 6–11, 14, 15, 19, 22–24, 26, 27].
A number of indices were calculated as follows to
estimate the frequency of occurrence of separate spe-
cies and their groups in the alimentary tract in an area.
The stomach fullness index (SFI, ‰) was calculated
using the equation by Zenkevich–Bogorov :
is mass of the stomach contents or of its sepa-
rate item and
is the mass of ﬁsh in a sample.
The mean stomach fullness index for the area sur-
veyed was calculated by adding the stomach fullness
indices calculated from each sample and dividing the
sum by the number of samples. The percentage of food
items was calculated using the partial and mean stom-
ach fullness indices obtained for the area examined.
The food composition was calculated as a simple aver-
age. The frequency of occurrence (FO) of a food item
was determined as the percentage of samples contain-
ing the food item to their whole number. The density
index (DI) of a food item was calculated using a stan-
dard equation  modiﬁed as follows:
is the mean relative biomass (%) and FO is the
frequency of occurrence of the food item. This equation
is more acceptable than the “relative importance index”
Feeding of the Snailfish
in Pacific Waters of the Northern Kuril Islands
V. S. Labai, Yu. N. Poltev, and I. N. Mukhametov
Sakhalin Institute of Scientiﬁc Fisheries and Oceanography, Yuzhno-Sakhalinsk, 693016 Russia
Received June 4, 2002
—This paper describes the feeding habits of the snailﬁsh
formes, Liparidae). The diet consisted mostly of crustaceans, among which decapods predominated comprising
up to 69.3% of the mean biomass of food organisms. Small shrimp (
nated the diet making up over 40.9% of the total stomach fullness index.
, feeding, Northern Kuril Islands.