Gold standard in salmon abundance measurement

Three Mat-Su Valley salmon counting weirs operated by the Sport Fish Division of the Alaska Department of Fish and Game during 2016 were used to make in-season adjustments to allow additional salmon harvests in Mat-Su sport fisheries.

After ADF&G started the season with significant king salmon restrictions on all Mat-Su king salmon fisheries targeting wild king salmon, escapement counts through Deshka River and Little Susitna River weirs allowed the department to return to standard regulations later in June on both rivers. In early July after the top end of the Little Susitna River king salmon escapement range was exceeded the department was able to allow bait fishing during the final eight days of the king salmon season. These two Mat-Su streams with weir counts were the only two locations where sport king salmon fishing was liberalized in-season during 2016..

After the Fish Creek personal use dip net fishery did not open for lack of a projection of 45,000 sockeye passing the weir, coho salmon counts exceeded the 1,200 minimum of the coho salmon spawning escapement range after the first week of August, and the department raised the coho salmon limit on Fish Creek and increased the time when sport fishing for salmon was allowed from two days per week to seven days per week. In addition, with the same Fish Creek weir information, the department also increased the daily coho salmon limit to three fish and increased salmon fishing time from two days per week to three days per week on Wasilla Creek/Rabbit Slough and Cottonwood Creek.

Without the in-season salmon escapement numbers provided by these 3 weirs it is doubtful that any of these liberalizing adjustments would have been made.

On the other side of the coin, lack of sufficient sockeye salmon escapement through the Fish Creek weir, as mentioned earlier, kept ADF&G from allowing the personal use dip net fishery in 2016, but by the time the weir was removed on Aug. 15, the midpoint of the Fish Creek sockeye salmon escapement goal had been exceeded with 46,202 sockeye having past the weir.

Lack of sufficient coho salmon passing Little Susitna River weir caused the department to cancel all Little Susitna River bait fishing after July 13. While this change was a big disappointment for sport anglers looking forward to the standard regulation that allows bait fishing starting on Aug. 6, it allowed a much higher percentage of Little Susitna River coho salmon to swim past the weir, and therefore, has also allowed nearly a full season of (reduced) sport opportunity on the river. Through August 30, 9,791 coho salmon have passed the Little Susitna River weir, and there is still a possibility that the minimum Little Susitna River coho salmon spawning escapement number of 10,100 fish may be attainted before the weir is scheduled to be removed in early September.

Late season coho salmon escapement numbers through the department’s Jim Creek weir have been much more disappointing. The department closed all sport salmon fishing in the Jim Creek drainage starting on Aug. 18, however, through Aug. 30 only 877 coho salmon had passed the Jim Creek weir. To put that number in perspective, of the four years ADF&G has weir escapements listed for Jim Creek on the ADF&G website, this year’s count is the lowest. The next lowest Jim Creek coho salmon weir count occurred only last year, when sport salmon fishing was also closed early. The difference is that in 2015, 3, 265 coho had already passed the weir through Aug. 30.

Although the department does not have a weir based escapement goal for the Jim Creek system, it does have an index count based goal for a portion of Jim Creek at McRoberts Creek. That goal is 450-1,400 fish, but more of Jim Creek’s coho salmon usually spawn in an area the Department calls Upper Jim Creek. A shortage of coho salmon in either of these important spawning areas would be undesirable.

There currently is no coho salmon escapement goal for any portion of the Susitna River drainage, although ADF&G has gone on record saying it will establish a coho salmon escapement goal for the Deshka River during the coming 2016/2017 offseason. The coho salmon escapement past Deshka river weir through Aug. 30, 2016, was 6,759 fish. Without a goal on the Deshka River fishery, bait was allowed from June 1 until now and the daily limit has been three coho per person. From all accounts I’ve heard, sport coho salmon harvest at Deshka River was significantly below average during the 2016 season.

Mat-Su salmon weirs previously paid for by ADF&G’s Commercial Fish Division include: Chelatna Lake Weir (Lake Creek drainage), Larson Lake weir (Talkeetna drainage) and Judd Lake (Talachulitna River drainage). Fish Creeks sockeye salmon weir counts were also previously paid for by the Commercial Fish Division, but are now funded by sport fish

In 2016, the department did not fund weir counts at Judd Lake weir, sockeye salmon counts seem to have been discontinued at Chelatna Lake after Aug. 6 because of high water (60,785 fish) and the sockeye salmon count at Larson Lake seems to have been discontinued after Aug. 24 (13,516 fish).

Salmon counting weir provide important management information about the health of the Mat-Su’s valuable salmon resources. With declining state revenue and tighter budgets some of Mat-Su’s weir seem to have already been seeing reductions. It remains to be seen how many of these projects will be fully funded in 2017. Sport fishing license fees have already been increased by the Legislature. Will increased revenue be sufficient to maintain important in-season Mat-Su salmon escapement information? Will the commercial fishery also shoulder increased costs for maintaining management efforts?

Andy Couch is a member of the Matanuska Valley Fish and Game Advisory Committee and the Matanuska Susitna Borough Fish and Wildlife Commission.