1063-0740/04/3004- © 2004
Russian Journal of Marine Biology, Vol. 30, No. 4, 2004, pp. 241–247.
Original Russian Text Copyright © 2004 by Biologiya Morya, Lukin, Vasil’ev.
It is known that every year the White Sea population
of the harp seal
comes into the
White Sea, where the animals mate, whelp, suckle their
pups, and molt [4, 5]. Gestational females form so-
called whelping grounds for the breeding and suckling
season. As Chapsky  recorded, depending on the
conditions of ice-setting, the whelping grounds are
formed either in Gorlo or in the central part of Bassein
(more often in the vestibule of Gorlo, and sometimes
even of Dvinskaya Guba) or in Voronka of the White
Sea. The whelping grounds were mostly settled in
Voronka, rather close to the Barents Sea ice margin.
Since the middle of the 1930s they began to be
observed much further to the southwest, in Gorlo and
the central part of Bassein. In the 1960s and 1970s, the
welping grounds settled, as a rule, in the inner part of
the White Sea .
Thus, the areas of the harp seal ground settling were
ﬁxed in the beginning and in the middle of the 20th cen-
tury. The present work analyzes the distribution of the
whelping grounds of the harp seal on the ice of the
White Sea from the 1960s to the 1990s. An attempt to
estimate the inﬂuence of the ice conditions in the White
Sea on the survival rate of the harp seal for those years
was also undertaken.
MATERIAL AND METHODS
Charts of the SUGMS aerial ice surveys for 1966–
1997, which were performed annually during the ice
season (November–June), were used as the material for
the present work. Each aerial ice survey was conducted
by a standard grid of routes for two days: the central
and the western regions of the sea were surveyed on the
ﬁrst day, and the east and the northern ones, on the sec-
ond. Concurrently with the parameters of the ice cover
recorded areas of seal occurrence on a
chart: “groups” of several individuals up to a couple
dozen seals, “patches” with a few hundred seals, and
“grounds” with more than a thousand seals. Air surveys
were carried out at an altitude of 200–300 m, which
enabled reliable observation of adult animals within a
range up to 1 km wide, and of their pups (“white coats”)
with a range up to 300 m in width. In some instances the
observers recorded the length of the en route ﬂight over
the seal grounds, which varied from 1 up to 10–15 km,
sometimes reaching 30 km. These data do not give
objective representation of the area of ice cover and of
the total number of animals in the seal grounds, as their
concentration, as a rule, was not uniform and had a pro-
nouncedly “patched” pattern. With the rather sparse
grid of traverses of the ice air survey (the greatest dis-
tance between them was 30–40 miles), there was the
possibility of missing a small seal ground between
traverses. Nevertheless, this method allowed large seal
grounds, which occupied areas of some tens km
, or a
part of them, to be recorded.
It is necessary to note that for various reasons the air
surveys were not carried in full scale in some years and
months; therefore, a number of observations were
missed in the survey series. Nevertheless, the total
amount of the material used in this analysis allowed
rather reliable assessments of the distribution of the
harp seal in the White Sea in the breeding season.
Some years one of the authors, L.R. Lukin, took part in several
surveys as an observer.
Distribution of the Harp Seal Whelping Grounds
in the White Sea 1960s–1990s
L. R. Lukin
and L. J. Vasil’ev
Institute of Ecological Problems of the North, Ural Branch, Russian Academy of Sciences, Arkhangelsk 163061
Northern Territory Hydrometeorological and Environmental Monitoring Service, Arkhangelsk
Received October 10, 2003
—Analysis of air survey data has shown that from the 1960s to the 1990s the whelping grounds of the
formed at the end of February through the ﬁrst days of March in two regions of
the White Sea: in the eastern part of Bassein and in Gorlo. The areas of the whelping grounds varied depending
on the current ice conditions. It was recorded that, despite ice conditions unfavorable for the pups’ survival that
developed in some years, in general the ice regime of the White Sea was favorable for reproduction of the White
Sea population of the harp seal.
drift ice, harp seal, pups, environment.