Seine boats fish a 2010 opening near Old Sitka Rocks and the Gavanski islands. (KCAW photo/Ed Ronco)

Alaska Dept. of Fish & Game officials are expected to do another aerial survey Friday to look for herring. A spotting flight on Wednesday found none, but herring predators are concentrated between Old Sitka Rocks and Dog Point.

Seine boats are showing up in Sitka Sound in advance of the 2012 commercial sac roe herring fishery. The fishery is one of the state’s most lucrative. Openings happen quickly and in limited areas.

This year, the fleet is expected to harvest more than 29,000 tons of the fish. They’re valuable for their roe, which is sold most heavily in Japan.

A 200-ton test set was taken from north of the Old Sitka Rocks Wednesday morning. The set was nearly 60 percent female and yielded 2.5 percent mature roe. The average weight was 161 grams.

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