NORWAY
Wednesday, July 11, 2001, 02:50
http://fis.com/fis/aquaculture/
Jan Ove Evjemo Ph.D. of the Norwegian University of Science and Technology (NTNU)
in Trondheim is criticising the Norwegian aquaculture industry for not
keeping up with progress made in marine fish fry production. While
hatcheries in the Mediterranean region use living, cultivated feed
organisms, the Norwegian industry mainly uses natural zooplankton harvested
from the sea.
Last year Norwegian hatcheries produced 500,000 cod fry and 250,000 halibut
fry. In comparison, in 1998 hatchery plants in Southern Europe produced 400
million sea bass and sea bream fry.
"By estimating the production yield of four kilo cod from one cod fry,
and six kilo fish from one halibut fry, and assuming a cod price per kilo of
40 Norwegian kroner (NOK) and NOK 70 for halibut, the total value based on
the fry production appears to be huge. But these figures could be greatly
increased if the principles applied in the Mediterranean were applied in
Norway," Evjemo told the popular science magazine Teknisk Ukeblad.
Evjemo believes the Norwegian industry must start using living, cultivated
organisms as fish fry feed. In his recently submitted thesis for a doctorate
at the NTNU, Evjemo shows how Norwegian hatcheries could increase marine
fish fry production by applying well-tried feeding methods from Southern
Europe.
"By using living and cultivated feed organisms producers could go
from seasonal to all-year-round production. However, such intensive
cultivation hasn't been given priority in Norway. Today the fry is fed
mainly natural zooplankton, which is harvested during the three-month summer
period, and copepods. This feed can become infected by parasites. There are
also large variations in the composition of species, density and nutritional
value of natural sea plankton," Evjemo told Teknisk Ukeblad.
He has, in addition to other living cultivated organisms, worked with
Artemia, which is a tiny crawfish that can be bought as eggs from large
producers in Europe and the US and then stored before being placed into sea.
After 24 hours producers end up with a first class feed for the fry.
However, colder, Northern European countries should bear in mind that
they'll need a different feed composition than Southern European hatcheries,
Evjemo explained.
The new Sotra-based company Cod Culture Norway (CCN), of which Dutch firm
Nutreco is the main shareholder, is following Evjemo's recommendations. CCN
is currently establishing Norway's largest cod fry hatchery with a total
capacity of 10 million fry per year, which will be operational from
December. Manager Rolf Engelsen told Teknisk Ukeblad that both plankton feed
and cultivated feed will be used, and he doesn't doubt that cultivated
organisms are the best feed. Engelsen said that such a project only based on
zooplankton would never be commercially interesting.