Íslenskar landbúnaðarrannsóknir - 01.09.1976, Page 9

TAGGING EXPERIMENTS AT KOLLAFJÖRÐUR 7
Table 4
The Groups of Smolts Tagged in 1972
Group number Age of smolt in years Number of smolts Type of tag Type of experiment
1 2 1998 Carlin tag Production return-rate
2 2 1992 Carlin tag
3 2 629 Carlin tag
4 2 995 Carlin tag with wire attachment Type of attachment
5 2 998 Carlin tag with poly ethylene attachment
6 2 1497 Carlin tag Photoperiod
7 1 970 Carlin tag
8 2 1000 Fin clipped left ventral Finclip vs. tag
Total 10.079
The total return of salmon to the Fish
Farm in 1972 was 681 fish. Of those 33 were
kelts and ca. 600 remrning as grilse. These
fish are entirely the result of the release of
ca. 8000 two-year-old smolts marked and un-
marked. This indicates close to 7,5% total
return of viable smolts, tagged and untagged,
released in 1971.
4. Length at Tagging versus Returns.
The only data of real value for this are those
from the release of tagged two-year-smolts.
The data are shown in Table 3. These data
show clearly the increase in rate of return
with increase in length as presented by
Carlin (1963, 1969) and Guðjónsson
(1972). The rates of return per centimeter