Ársrit Fiskifélags Íslands - 01.01.1933, Blaðsíða 75

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well, though as yet their value cannot be judged with any
certainty.
As far as was possible the percentage number of fish spaw-
ning at different times was investigated, but unfortunately it was
impossible to gather much material for such investigations. In
Hornafjörður experiments of this kind were made in April and
May, cf. tables nos. 5, 6 and 7, resulting as follows: a) The largest
fish spawned quantitatively, 93 °/0 of the 90—95 cm. fish spawning,
90 °/0 of the 80—85 cm. fish, 50 °/0 of the 70—79 cm. fish, and
14—20 °/0 of the fish smaller than 70 cm. b) About 16 °/0 of the
seven year old fish spawn, about 50 °/0 of the 8 year old, about
70—75 °/0 of the 9 year old, and about 86 °/0 of the 10 year old.
The older fish spawn about quantitatively. c) About 83 °/0 of all
the fish spawned in April (27th), but 86 °/0 in May (2nd). d) The
young fish seem to spawn earlier in the season than the old
(Friðriksson, 1931, p. 66). e) The same fish seem to spawn every
year and not e.g. every other year. Some spawning seems to have
taken place off the North-West of Iceland already in February
(Table 19), especially amongst the youngest and smallest fish.
We have tried to ascertain in the light of the work expen-
ded the intensity of the catch, by measuring the catch as follows:
a) by the number of fish caught on every 1000 hooks, b) by the
nurnber caught in ten nets, or c) in one hour’s trawling; in other
words the intensity of the catch has been measured as the num-
ber of fish caught in proportion to the energy expended. Accor-
dingly it has been ascertained how many fish of each year have
been caught with a definite expenditure of energy, and the result
of this investigation is given in tables nos. 10, 15, 16, 20, 25, 31,.
35, 36 and 37. Such investigations as these will no doubt prove
very valuable in the future, when material from past years has
been collected.
II. The Herring-investigations. In Keflavík 520 herrings
caught by deep-sea nets in May were examined. There was no
food in these herring. The size was 27—36 cm., but mostly 31—
32 cm. (p. 48). The majority were herring of five and six years
(table 38).
A great deal of herring was caught at East Iceland during
the greater part off the year. They were much smaller than the
herring caught off Northern Iceland, the majority of the former
being from 25—30 cm. (v. table p. 50). The age of the herring
caught in Jan. was investigated and the majority of it proved four
and five years old (54 °/0 and 37 °/0). Off North Iceland 5,581 her-