By KLAS STOLPE
Sentinel Staff Writer
The Alaska Department of Fish and Game observed a little over 14 nautical miles of active herring spawning in an aerial survey of Sitka Sound today.
The widespread spawning was another indication, if any was needed, that there would be no commercial sac roe seine opening this year, since that requires an area where mass spawning has not yet occurred.
Also, since regular sampling and surveys from the water and the air the past two weeks failed to locate any herring schools with average size and roe content high enough for marketable sac roe, most of the seiners who had been standing by since March 17 have already left town.
Fish and Game’s annual measuring and mapping of the herring spawn is now under way.
“This is one of the best spawning days we have seen,” Sitka area management biologist Eric Coonradt said. “It will probably go on for a while longer. It will be hard to say today is peak spawn until we have a couple more days.”
Today’s survey covered Sitka Sound from Windy Pass to Salisbury Sound, F&G said in a news release.
Calm winds and clear skies allowed a clear view of herring schools along the Kruzof Island shoreline and in Krestof Sound, and 14.2 nautical miles of active herring spawn along Kruzof Island and in the Magoun Islands.
A high concentration of herring predators was spotted along Kruzof Island in Hayward Strait, and Neva Strait.
The cumulative spawning mapped to date is 15.9 nautical miles.
Coonradt said he expected send out a skiff with a department biologist this afternoon to take samples of spawn.
“We are currently just mapping spawn and taking age, weight, and length samples from the spawn to determine composition of the spawning biomass,” he said. “This will be followed up by the dive spawn deposition survey.”
That accumulated information will be sent to ADF&G’s statewide fisheries scientist Sherri Dressel to work into the herring model.
This year’s guideline harvest level was 12,869 tons, based on a 20 percent harvest rate of a forecasted mature biomass of 64,343 tons. Last year the quota was 11,128 tons, but the fishery closed after seiners took just over 2,926 tons in a cooperative fishery.
The department’s goal this year was to fish on stock averaging 110 grams weight and close to 11 percent mature roe but weak early test fisheries resulted in F&G not having an opening and discouraged industry and commercial fishermen.
The 2019 pre-fishery biomass of 62,343 tons, expected to contain 43 percent of 96-gram, four-year-old herring (24,350 tons) and the entire overall average per herring was expected to be 108 grams. It was expected that five-year old herring (101 gram average) would account for 21 percent of the forecast or 12,874 tons; seven-year-olds (151 gram) 18 percent or 16,246 tons; three-year olds (80 gram) 12 percent or 5,746 tons; eight-year-olds and older (155 gram) four percent or 3,874 tons; and six-year olds (127 gram) two percent or 1,253 tons.
