DULUTH  (AP)  -- A busy saltwater shipping season is coming to an end at the Twin Ports harbor.

The usual three-blast salute from the freighter Nogat as it steamed under the Aerial Lift Bridge was silent Wednesday afternoon. The horn was frozen.

Capt. Dariusz Nowicki says the freighter was coated with ice as it crossed Lake Superior. Tugboats nudged the Nogat into port where it will be loaded with 12,000 tons of flax and wheat bound for Amsterdam. Departure is likely Friday.

The Seaway Port Authority tells the Duluth News Tribune shipping traffic is up 25 percent this season and grain shipments increased 60 percent.

Great Lakes freighters will be on the move through mid-January.

(Copyright 2010 by The Associated Press.  All Rights Reserved.)

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