European scientists say cod and herring populations in the North Sea are not reproducing enough, jeopardizing the Norwegian fishing industry.
Researchers in Norway, England and the Netherlands are trying to determine why at least 15 types of fish have moved farther north to colder water, Aftenposten reported Monday, noting some fish not usually seen in the North Sea, such as the swordfish, have been observed.
The North Sea's average temperature has risen by as much as a full degree during the last 10 years and that might have affected the cod and herring, since both species prefer cold waters.
"There's little adult cod left in the North Sea," Geir Ottersen of the Institute of Marine Research in Bergen, told Aftenposten. "A main reason we believe is overfishing of large fish. With the herring, the adult population is solid, but there hasn't been much reproduction the past three years. We don't know why, but we're assembling all the facts and studying possible reasons for why this is so."
Copyright 2006 by United Press International
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