The Alaska Department of Fish and Game requires 3,000 tons of spawning biomass to open the Seymour fishery near Admiralty Island in late spring. Last year the fishery didn’t reach that amount. This year there will be enough fish–the biomass is estimated to be above 5,000 tons–but the department has decided to hold off on the fishery anyway. The main reason is that most of the population—75 percent—are four-year-olds and aren’t big enough.
Dave Harris is the Juneau Area Management Biologist for the State.
“Because the little fish go through the nets, you’d basically have to be sifting quite a few fish in order to catch the ones you really want,” Harris said.
That process could lead to more mortality. Plus, interest in the fishery is down.
“The fish that the gill netters like to target are typically larger 6,7,8 year old fish,” Harris said, “just a larger fish, more marketable, have more roe in them and that sort of thing.”
So, why are there this many age-four herring? Harris said four years ago when the fish hatched the environment was just right. There had to be enough of the right sized plankton for the herring to eat as they grew.
“Things have to line up just right for the herring to survive,” Harris said. “So, when they come out there has to be an abundance of small quality food for them and then as they grow, get larger they need successively larger sizes of food.”
Also, the herring’s parent years were unusual. In 2011, only one processor participated in the Seymour fishery. In 2012, not many herring were harvested because they came to shore to spawn in small groups over a few weeks instead of in one large mass. It just wasn’t cost effective for fishermen to go after them that year.
Harris said it’s not just Seymour that’s seen a lot of four year old herring. Biologists have seen the same thing around Southeast. Scientists sample the fish every year and then plug that information into models that give them an overall population estimate.
The Seymour Canal fishery is not as popular as it used to be for fishermen. Harris sayid the fishery has drawn ten to twenty participants in recent years but in the past it’s been as high as 40 or 50. The value of the fish is lower now. Demand from the main buyer—Japan–is down. But the supply remains high.
“There were years when they’d get a thousand plus dollars a ton and that was a pretty lucrative fishery but in recent years it’s down in the more 100 to 150 dollars a ton value,” Harris said.
Harris said processors also weren’t that interested in the Seymour gill net fishery this year.
The department weighs all of that information and then also looks at their own budget which has been seeing cuts.
“It seems the cost to manage the fishery would be more than the actual value of the fishery so that’s certainly a contributing factor,” he said.
But not having a Seymour opener is not all a bad thing, according to Harris. There’s every reason to believe that there will be a healthy harvestable fishery when the herring are a bit older.
“So, this is really a very positive thing, said Harris. “By not harvesting four-year-olds this year there will be that many more come back as five-year-olds and more harvestable size and better value.”
Herring populations are known to go through big fluctuations. In Seymour Canal, there were five years in the 1990s that had closures before stocks built back up. Harvests have also seen fluctuations. Annual landings from gill nets have ranged from 302 tons in 1987 to a high of 1,519 tons in 2003.