Spring chinook run seems low and late

 


Just 3,337 spring chinook had been counted passing upstream over Bonneville Dam as of April 30, the lowest count of the fish at the dam on record for that date.

Anglers in the lower Columbia River caught nearly twice that number in March and April and neared the limiting number that is calculated to protect upriver fish before fishing downstream of the dam ended April 23. And river managers said May 2 they are also allowing angling to end in the area upstream of Bonneville Dam to the I-395 Bridge.

“Unfortunately, this is the lowest cumulative count at Bonneville on record,” Stuart Ellis, the U.S. v Oregon Technical Advisory Committee (TAC) lead for 2017 and harvest management biologist with the Columbia River Inter-Tribal Fish Commission, said of the passage count as of April 30.

However, at this point in the run, TAC is unsure what the implications would be for its spring chinook run size update, an update it usually makes in the first week of May. TAC met Monday, May 1 to take a look at the run size, but it was not able to do the typical first of May update, Ellis said.

“We need to have about 50 percent of the run over Bonneville before our updates are any good,” he added. “Possibly by next Monday, we may be able to say something with a bit of certainty about the run. However, this will need to be a record late run if it is going to get anywhere close to forecast.”

The early season forecast was 160,400 upriver spring chinook and Snake River spring/summer chinook salmon. The total 2017 spring chinook forecast – including upriver and lower river chinook – is down 17 percent to 227,890 fish from the 2016 actual run of 274,652 fish.

Some 34,540 spring chinook had passed Bonneville last year by April 30, and the 10 year average is 56,644.

The pace of passage is picking up. In the week leading up to April 30, about 200 fish or fewer were passing the dam each day. The April 30 count picked up to 362 and on May 3, the daily count was 836 fish, for a total of 5,192 fish over the dam. That’s still fewer than the 6,500 spring chinook anglers have caught in the lower river and far below the 10-year average of 75,463 fish. Last year by May 3, 69,462 fish had passed, with more than 10,000 of those fish passing May 3.

However, Ellis said, 2017 is still the lowest cumulative count as of May 3 ever. The five previous low years on May 3 are:

--1949: 6,894 fish past Bonneville by May 3 (2017 is 75 percent of this total) and by June 15 the tally was 65,104;

--1995: 7,241 past Bonneville (2017 is 72 percent of this total) and 12,783 by June 15;

--1952: 9,322 past Bonneville (2017 is 56 percent of this total) and 142,226 by June 15;

--1956: 12,121 past Bonneville (2017 is 43 percent of this total) and 73,675 by June 15;

--1950: 13,326 past Bonneville (2017 is 39 percent of this total) and 67,729 by June 15.

High, cold and turbid water may be causing the adult salmon to hold longer in the lower river, but one of the problems may go back to the year the juvenile chinook left the river – 2015 – when river conditions were low and the water was much warmer than normal.

“The bulk of the return this year would be 4 year old (2-ocean fish) that migrated out in very poor conditions in 2015 and went into an ocean that people generally believe was very poor for salmon,” Ellis said. “Our pre-season forecast was down this year because we didn’t think we had great survival of these fish. The question will be is whether things were worse than we anticipated.”

It’s difficult to know how many fish the spring run will add up to. The count of spring chinook is based on a management period up through June 15 and TAC “will use whatever goes over Bonneville during that time period plus the fishery mortality on upriver fish in any of the lower river fisheries during this time period to calculate the river mouth run size,” Ellis said.

He added that the U.S. v. Oregon Management Agreement has a harvest rate schedule that says what the allowed catch for treaty and non-treaty fisheries is at any particular run size. For a run size of 160,400 fish, the early fisheries allowed catch is 6,905 spring chinook, which includes a 30 percent buffer that is applied prior to the first run update. See the Oregon and Washington Columbia River Compact’s April 12, 2017, Winter Fact Sheet No. 11 (http://www.dfw.state.or.us/fish/OSCRP/CRM/FS/17/17--04--12wf11.pdf).

“TAC will start updating the run just as soon as we think we can start making a reasonable guess,” he said. “Normally that is when around 50 percent of the fish are over Bonneville. The predictions are very volatile if we do them too early. Both treaty and non-treaty fisheries will be stuck dealing with however the numbers come out.”

Anglers so far this season have taken about 6,500 fish, which includes those fish landed by sportfishers plus release mortality on upriver fish, and lower river commercial gillnetters in off-channel select areas have caught about 75 upriver fish. The areas they can fish have been somewhat reduced to cut down on upriver impacts. Also, the Zone 6, Bonneville Dam to the I-395 bridge at the Oregon Washington border, has just one reported upriver mortality and is receiving very little pressure. The fishery closes this evening.

Earlier in the season, poor fishing had been due to river conditions with higher, colder and more turbid water than normal.

“Flows at Bonneville this April represented the highest flows on record for the month in the last 100 years and the fish are not in a hurry,” said Ron Roler, a Columbia River fishery manager for WDFW.

Test fishing by the Washington Department of Fish and Wildlife is continuing to show a significant increase in chinook abundance in the lower river, he said.

“The only test fishery that is operating now is in Cathlamet Channel,” Roler said. “The catches in our test fisheries are some of the largest we have seen, but I don’t believe that it means the run is one of the largest, it just means that we have upriver fish throughout the river and they will eventually decide to move past the dam.

“The only fishery we could extend now is the fishery above Bonneville Dam, but we thought that it would serve the greater good to wait until we have more fish above Bonneville to extend the fishery,” he said.

“While it is certainly possible that this year’s run will come in way below forecast, there are some things that suggest the fish are just quite delayed,” Ellis said. “Both non-treaty commercial test fishing in the Lower River and Cathlamet Channel along with some research fishing NOAA does to try to estimate sea lion predation both seem to indicate based on catch rates of upriver fish, that there should be good numbers of fish still downstream of Bonneville.”

Some tribal permit gillnet fishing is going on now above the dam for ceremonial use along with Zone 6 platform and hook and line fishery, which is open for subsistence use, Ellis said. The tally so far is around 500-600 fish.

“If we did happen to downgrade the run to less than 90-95K, then depending on where the states actual catches are, they would have to start closing fisheries,” Ellis said. “The tribes could still keep fishing for a bit, but at a pretty reduced level.

“Hopefully the fish will start streaming over Bonneville pretty darned quick and nobody is going to have to take any drastic fishery actions, but that is kind of how things would play out if this run were to really not materialize,” he concluded.

 

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