The Alaska Department of Fish and Game cannot undo a set of Cook Inlet driftnet restrictions in place over the last 25 years.

Cook Inlet driftnetters say restrictions unjustly keep them from millions of dollars of sockeye harvest based on faulty data. Protective measures for Susitna sockeye, a designated stock of concern, keep drifters in specific corridors in Cook Inlet from July 9 to 31. Fishermen say the decades have added up to thousands of available sockeye — and millions of dollars — they didn’t need to forgo.

The department, the fishermen believe, has no reason to continue the restrictions. ADFG managers say they have no money or resources to make the adjustments.

“When they redid the sonar, they found out they were in effect, under harvesting those stocks and overescaping,” said Erik Huebsch, vice president of United Cook Inlet Drift Association, an industry group. “They knew they were managing way too conservatively based on that. Why didn’t they change the management to ratchet it up any more if they knew they were managing too conservatively?”

The Alaska Department of Fish and Game, or ADFG, says the driftnetters’ concerns are well-founded.

“They have a legitimate question and concern to have some restrictions removed when there’s going to be a surplus,” said Pat Shields, ADFG’s commercial manager for Upper Cook Inlet.

However, apart from three lake-based escapement goals, though, Shields said there’s nothing on which to base new management.

“Right now we don’t have a tool other than those three weirs. With the funding we’re looking at right now, we’re really challenged to find a new method.”

The study

A 2009 study presented to the Board of Fisheries discredited the basis for the drift fleet’s restrictions.

In 1981, ADFG installed a Bendix sonar system at the mouth of the Yentna River, a Susitna River tributary. Susitna sockeye stock is particularly difficult to enumerate; the river is wide and murky, and a multitude of the other salmon species — pink, chum, coho, and chinook — fog the sonar numbers trying to pinpoint sockeye.

To mitigate, ADFG based much of Susitna sockeye management on the Yentna River’s sockeye escapement, figuring the river accounted for roughly half the overall Susitna’s.

Since the 1981 Yentna Bendix start date, the river’s measurements have always seemed off, frequently missing the sustainable escapement goal. During the 1989 Exxon Valdez oil spill, the Cook Inlet drift fleet was closed by emergency order, but the Yentna sockeye escapement remained largely unchanged from other years. By 2006, five of the last nine years had failed to make the sustainable escapement goal of 90,000 to 160,000 sockeye.

Eventually, the department got curious enough about the chronic underperformance to question the method. Using extra funds from various sources including the Cook Inlet Aquaculture Association, the department stacked the Yentna with extra counting methods like fish weirs, DIDSON sonar, and mark-recapture studies, to compare the results to the Bendix sonar.

The results punctured the decades of Yentna Bendix counts.

“There is little confidence in the reliability of the Bendix sonar estimates,” the report reads. “Since 2006, when additional escapement studies began, Bendix sockeye salmon estimates have ranged from 56 percent to 76 percent of the DIDSON estimate, and just 31 percent and 32 percent of the Yentna River mark-recapture estimates in 2007 and 2008.”

The board made a major change to the river’s management in 2008 by declaring Susitna sockeye a “stock of concern” just before the 2009 study came out. That year, the Bendix sonar counted 90,000 compared to more than 130,000 that both DIDSON sonar and weirs counted and well within the sustainable escapement goal.

The stock of concern designation placed additional restrictions on the Cook Inlet drift fleet to protect the erroneously underestimated Susitna sockeye.

After the report, ADFG changed the escapement goals from the Yentna River’s Bendix-based goal to a series of goals on nearby Chelatna, Judd, and Larson lakes. The stock of concern designation and its resulting drift restrictions, however, remained.

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