| dc.description.abstract | This is a preliminary report on the Norwegian
capelin investigations started in 1960. The general
distribution and life history of the species is discussed.
Special attention is drawn to the high postspawning
mortality, which is evident from the age
composition of the adult stock and the masses of
dead capelin found adrift or on the beaches after
the spawning season. In the summer of
1961 considerable numbers of female capelin maturing
for a second time were observed in the northeastern
part of the Barents Sea. These were of the
1957-yearclass which made up the bulk of the
spawning stock at the Norwegian coast in 1961.
The Norwegian purse seine fishery for capelin
has developed greatly during the past decade, and
a record catch of nearly 220,000 tons was landed
in 1961. However, this quantity was probably only
a small fraction of the available stock, and the possible
effect of the fishery on stock and recruitment
is unlikely to be of any significance.
The fishery is entirely based on spawning and
prespawning concentrations of capelin duTing the
latter part of winter and early spring. Except for
five successive years, i.e. from 1938 to 1942, during
which the capelin failed to appear on the traditional
spawning grounds at the Norwegian coast, there
has been capelin spawning at the Finnmark coast
each year for more than a century, at least. Annual
records since 1868 show that the time of arrival
at the coast, and probably also the magnitude of
the spawning stock, have fluctuated greatly, but in
most years the first schools have reached inshore
waters in February or March.
It appears that early arrival is associated with a
westerly distribution of the spawning capelin and
vice versa, and a few years of early or late arrival
usually follow in succession, but with no regular
periodicity.
A relation between the date of arrival at the
coast and lunar activity seems to exist, suggesting
that the spawning migration may in some way be
influenced by tidal effects.
The 1961 season was favoured with an early arrival
of the capelin and hence an extended season,
mostly good weather, and a favourable distribution
of the fish, which were unusually large, fat and easy
to catch. As is apparently a general experience, the
capelin came in several distinctly separated batches,
of which there were three main ones. The
first schools struck land on February 17, and were
gradually distributed along the coast west of North
Cape. The next influx came to the coast of the
Varanger peninsula during the first days of March,
and thereafter moved westwards. Finally, in April
there was a new invasion along the northern Varanger
peninsula.
There were slight variations with time in the
size distribution, and a profound change in the sex
proportion, the males being in great majority by
the end of the season.
In September 1960 the capelin seemed to be distributed
along the cold/warm water front in the
northeastern Barents Sea. The greatest concentTations
were found in an area NE of Hope Island.
The capelin, which were very fat (up to 23.4 %),
at times occurred in dense schools near the surface.
During August the following year experimental
fishing was conducted with a purse seiner and a
trawler using mid-water trawl. However, this year
the capelin were more widely scattered over large
areas to the north and east, and the distribution
seemed to be entirely unrelated to the prevailing
hydrographic conditions. Only on two occasions
were capelin found in abundance for commercial
exploitation, and about 320 tons were caught,
mainly by the purse seiner. | en_US |
