Translation Series No.1211

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Umfang = Cire umference
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factors during the season. We can say with certainty that the highest
values that appear in December and January (line catches) or also in
February (net fishing) represent best the stock density. Lower values
during the fall may be attributed to the temperature conditions, because
cd.-Éke,s
the salmon return only gradually to the surface. The dropping -c-ap-tur-es ,
per unit effort in February/March do not reflect with certainty the strength
of the stock.
The question is now in what manner would it be possible to
cad,
obtain an average value for the -capture per unit effort during a season
that would represent best the density of the stock. In the first place,
the highest values of each season might be considered to be representative.
It is, however, not necessaryfor us to use exactly these statements. The
et„.teite5
decisive demand that must be made of the captures per unit effort is that
they should be directly Comparable from season to season. In regard to the
line fishery we can, for examPle, compare the December values of the years
1956 to 1958 with one another, which brought the highest :captures per unit
effort of each fishing season. The result for December 1960 can, however,
not be included in this comparison because the highest value of this season
Cm
so
ne • 745
Liirg .e = Length
. ,
.
Fig. 8. Relation between total length and circumference in
the salmon (the curve has been drawn with the aid of ,
.
group aVerages).
en1 .