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Economic and dam related articles

Fish Runs in 2003 Expected to Slip from Record Highs

by Barry Espenson
Columbia Basin Bulletin - December 20, 2002

The 2003 return of upriver spring chinook salmon to the Columbia River basin may not match counts of the previous two years, but officials say the return should still afford plenty of fishing opportunities up and down the river.

A forecast of 145,400 upriver spring chinook salmon returning next year to the mouth of the Columbia would seen to pale in comparison to the 333,700 that returned this year -- the second highest run since record keeping began in 1938. The record was set in 2001 with a return of 416,500 upriver spring chinook. The adult return was 178,000 in 2000.

"Those runs we saw (in 2001 and 2002) were extremely high runs," said Patrick Frazier of the Oregon Department of Fish and Wildlife.

Recent years have witnessed a surge in adult returns for most Columbia basin salmon and steelhead stocks. The improved stock status is believed to stem from a variety of factors -- manmade improvements in habitat, mainstem passage and harvest and hatchery practices, favorable in-river conditions when the fish were migrating as juveniles to the sea and a wild card -- ocean conditions. Cyclical changes in ocean and climatic conditions are believed to have taken a turn for the better that has improved survival for Columbia Basin-born fish during their formative saltwater years.

The basin's upriver spring chinook have literally risen from the depths -- record low returns of only 21,100 in 1994 and 10,200 adults in 1995. As recently as 1998 and 1999 the adult returns were only 38,400 and 38,700 respectively. The 145,400 total would be the fourth largest since 1973.

Federal, state and tribal officials makes the run predictions based on a "reconstruction" of the current year's return. It basically charts, for each stock, the age class structure of the current run and predicts how many of a particular brood year's fish will return the following year -- a year older and hopefully fatter.

"We didn't have many of the younger age class fish come back" as compared to recent years, said Stuart Ellis, a harvest management biologist for the Columbia Inter-Tribal Fish Commission.

Still, the forecast is far from cloudy. The upriver spring chinook forecast includes an estimated return of 25,000 wild and 47,500 hatchery Snake River fish. That compares to 60,200 wild and 72,500 hatchery fish last year. The 1986-1999 average Snake River wild spring chinook return was 7,900 adults.

The Upper Columbia River spring chinook run is expected to be down considerably, although Frazier says that stock is also the most difficult to predict. The tally in 2002 was 6,300 wild and 46,800 hatchery returns. The prediction for 2003 is only 1,300 wild and 11,900 hatchery returns.

The upriver summer chinook return is forecast to number 87,600 next year as compared to 129,000 in 2002. That 2003 forecast includes about 19,300 Snake River summer chinook, of which 7,700 would be wild fish. That is a decrease from 2002's 27,900 overall return but an increase from that year's wild run of 4,500 Snake River summer chinook.

The 2002 upriver summer chinook run was the largest since 1959. A 2003 run of 87,600 would be the second largest since 1962.

Willamette River spring chinook are expected to produce another strong run in 2002 with an estimated 109,800 adult returns. That would be the third-largest run since 1970, Frazier said.

The 2003 sockeye forecast would represent a severe decline, from 49,600 to 22,000, from 2002. A run of 22,000 would be the sixth smallest since 1938. The vast majority of the sockeye head to the upper Columbia but a small number swim toward Idaho's Snake River. That remnant stock, now propped up primarily by a captive broodstock program, is expected to return about 80 adults next year.

The Snake River sockeye was the first Northwest salmon stock listed under the Endangered Species Act. It was given endangered status in 1991. Of the spring and summer returns, Snake River spring/summer run, Lower Columbia, Upper Willamette, and Upper Columbia spring chinook stocks are now listed. Also listed are the Snake River, Upper Columbia, Lower Columbia, Upper Willamette and Middle Columbia steelhead stocks. Non-tribal fisheries now target unlisted hatchery stocks.

Sockeye, Frazier said, seem to be particularly vulnerable in years when there are lesser flows in-river during their migration to the Pacific Ocean. That was the case in 2001's severe drought.

Federal hydro system operators, struck by drought and the need to generate as much power as necessary during that spring and summer energy market crisis -- called off most operations, such as spill, that are intended to ease salmon passage down through the system. The focus instead was to transport via barge as many fish as possible through the system to reduce their exposure to low, warm flows.

The TAC forecasts focus largely on those statistical relationships between age classes. It is virtually impossible to estimate the individual effects of such variables as those low flows, the long-term effects of barge transportation on the smolts that are released below Bonneville, or changing ocean conditions.

But the overall effects are factored in naturally because a key portend of things to come is the number of jacks that return. Jacks are salmon that return to freshwater after only one year in the ocean. The bulk of their brood class returns in succeeding years.

"The fish that went out in the bad water year came back as jacks this year," said Cindy LeFleur of the Washington Department of Fish and Wildlife. Their rate of survival in effect takes into account river, estuary and ocean survival.

The young fish that did reach the estuary in 2001 could also have been affected there. Both Frazier and Ellis said it is generally accepted the initial few weeks when the young fish adapt from freshwater to saltwater creatures can be crucial. If low flows diminish the Columbia River "plume," -- created where the freshwater flows into the ocean -- it can make the fishes' transition more difficult.

Although unproven, "it's reasonable to assume that that would have an effect," Ellis said.

Next year's upriver summer steelhead return is expected to continue a strong recent trend, with the forecast slightly surpassing a recent five-year average return that has been inflated by the top two returns in post-dam construction history. The record return of 630,200 steelhead poured past Bonneville Dam in 2001, followed by the second highest total since 1938 -- 478,000 -- this year. Those totals pushed the five-year average to 354,500 upriver steelhead. The forecast for 2003 is 360,900.

The 2003 forecast predicts 64,700 "B" index steelhead will make the run up the Columbia and Snake River to Idaho hatcheries and spawning grounds. That total includes 53,200 hatchery returns and 11,500 wild returns. Both totals would be near the five-year average. The 2002 B return was 97,600 hatchery and 32,300 wild fish.

The 2003 "A" prediction is for a run of 279,600 steelhead returning to hatcheries and tributaries across the Columbia and Snake river basins. That compares to a return of 323,100 in 2002. The 2002 A forecast is split with 209,000 hatchery and 70.600 wild fish expected. The wild portions of the Middle Columbia and Snake River steelhead stocks are listed as threatened under the Endangered Species Act. Hatchery and wild steelhead from the Upper Columbia are listed as endangered.

Also expected to return upriver are 16,600 Skamania stock steelhead, including 12,100 hatchery and 4,500 wild fish. That would compare to a 25,000-fish return in 2002 and a recent five-year average of 17,400.


Barry Espenson
Fish Runs in 2003 Expected to Slip from Record Highs
Columbia Basin Bulletin, December 20, 2002

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