| dc.description.abstract | During the second half of 1984, T. sagittatus invaded the Norwegian coastal
waters, but less abundant than in 1983. During the spring and summer 1985,
squid was present in small numbers. In the autumn of 1985, T. sagittatus
again frequented Norwegian waters, more abundantly than in the previous
year.
Materials for investigation were obtained from research cruises near Shetland
in July 1984, from Norwegian coastal banks in April and August-September
1985 and, through the courtecy of the Faroese Institute of Fisheries Investigations,
from the Faroes in August 1985. During September-December 1984,
samples of squid were also obtained from commercial catches along the coast of
Norway.
From July to December 1984 the mean dorsal mantle length (DML) of the females
increased from near 21 cm to about 33 cm. In April 1985, females
measured 33-43 cm. In August 1985, the squid at the Faroes measured 24 cm
in average, similar to those from the Norwegian coastal banks in August-
September. In the latter area, a few larger females, ML 42-47 cm, were also
present.
The stomach contents were mostly dominated by small fish, mainly blue whiting
and pearlside. At the Faroes, a decapod, not identified, was also frequent.
In stomach contents of squid from commercial catches at the coast of Norway,
squid remains were common.
The liver percentages were very variable, with mean values mostly below 10%.
Age determinations, based on counts of primary growth rings in the statoliths,
confirmed observations from earlier years , with mean ages of 9-10 months .
This also applies to squid caught in April.
Squid, caught during July-October 1984, were supposed to be hatched in
November 1983-January 1984, those caught in December, in January-March
1984; those taken in April 1985 were hatched in June 1984. Squid, caught in
August-September 1985, were mainly hatched in November-December 1984.
In 1984 the commercial fishery yielded about 8 000 tons, in 1985 close to 14 000
tons. | en |
