Editor's note: This story was updated on Monday, July 25 with Fish and Game's set gillnet fishery restrictions.
Along with restrictions on sport fishing in several parts of the Cook Inlet, the Alaska Department of Fish and Game's commercial fishing division has issued a pair of emergency orders closing the Northern District of Upper Cook Inlet as well as the Kasilof section of the Upper Subdistrict to set gillnet fishing from 7 a.m. to 7 p.m. on July 25. The Kasilof portion of the set gillnet fishery had been set to open Monday.
The fishery is managed for sockeye salmon return. Fish and Game officials said they would incorporate things the department learned during the large sockeye and low king return last season in management decisions.
“The way we did that last year was we fished an abnormal fishing pattern,” commercial fisheries area biologist Pat Shields said. “We fished drifters when the setnetters were closed.”
Shields said the setnetters catch more king salmon than the drift netters do so his division tried to give the kings a boost by restricting that part of the fishery.
“We traditionally don’t do that,” he said. “We traditionally put both in the water at the same time and let the fish decide who gets to catch them. When you allow one to fish and not the other, there needs to be a compelling reason to do so.”
Shields said Wednesday that the staff continues to “hash this one out,” and there could always be restrictions announced in-season.
The Kasilof commercial fishery, can open as early as June 20 according to its management plan, however this usually only happens if 50,000 sockeye are counted in-river by that date.
For the third year, two DIDSON sonars mounted on the North and South banks of the Kasilof River, about 8 miles from the mouth near the Sterling Highway Bridge, began their count of sockeye on June 15.
As of Friday more than 16,800 sockeye were counted in the river according to Fish and Game.
Shields said the Kasilof section of the set gillnet fishery has opened early in the past including 2011 when it opened one day early.
“The escapement goal is 150,000 sockeye salmon in the Kasilof river and if you have 50,000 fish already escaped in the river you’re already one-third of the way into your goal and you haven’t even fished yet,” he said.
Officials forecast 754,000 sockeye to return to the Kasilof river during 2012.
Part of the management plan also requires the department to try to harvest the run in its entirety.
“It allows for genetic diversity in your escapement,” he said.
During the 2011 fishing season when the commercial fishing division had to manage a strong sockeye run while coping with a low king run, Shields said the department learned several things that could help with managing a similar run this year.
“First thing we learned was that it can occur,” he said with a laugh. “Although it is a rare event where sockeye are very strong and kings are far below average and fortunately for everyone it doesn’t occur often.”
Shields said managing the sockeye run was particularly challenging for the department this year as last year’s run resulted in a stronger than normal escapement into the river which could cause problems as well.
Despite the abnormal fishing pattern, the final sockeye salmon sonar estimate in the Kenai River was about 250,000 higher than the upper range of the in-river goal.
ADF&G estimates that a run of 6.2 million sockeye will return to the upper cook inlet with a total harvest of 4.4 million.
That harvest is 400,000 sockeye above the 20-year-average harvest according to a fish and game forecast media release.
“What you would try to avoid if you can is to have another over-escapement event,” Shields said.
Mark Willette, fisheries biologist, said the department has observed that in years when there are overly large escapement the increased competition for food in-river lowers the average number of fish that return from those years.
Shields said the commercial fishery needed to harvest the sockeye run to keep from having too many fish get into the river.
“What we’ve found is that if you put another overly large escapement into the system they, on average, don’t survive well,” Shields said.
Editors Note: This article was corrected to reflect the correct opening date of the Kasilof portion of the set gillnet fishery and biologist Mark Willette's name.
Rashah McChesney can be reached at firstname.lastname@example.org