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Sockeye run edging toward record-smashing 600,000 fish; Most headed for Okanogan Basin

Sockeye Run Edging Toward Record-Smashing 600,000 Fish; Most Headed For Okanogan Basin

Posted on Friday, July 11, 2014 (PST)

The sockeye salmon tally this year at the lower Columbia River’s Bonneville Dam on Tuesday, July 8, set a record for any season since the construction of the dam was completed in 1938 and the counts began.

Mid-summer sockeye spawners counted passing Bonneville through Tuesday totaled 526,367, and counting.

The record for an entire season was a 515,673 fish count in 2012.

Another 12,858 sockeye were counted passing the dam Wednesday to up the record to 539,225.

Fishery officials as of Monday estimated that the 2014 sockeye return to the mouth of the Columbia River will total more than 560,000 fish. That forecast is up, based largely on dam counts, from a preseason estimate of 347,000 sockeye.

“If we had updated the runs today, they would have been higher,” the Columbia River Inter-Tribal Fish Commission’s Stuart Ellis told the Columbia River Compact Wednesday. Ellis chairs the Technical Advisory Committee, a panel of federal, state and tribal fishery experts that makes predictions, and updates predictions, of salmon and steelhead returns to the Columbia/Snake river system.

“We would probably be looking at a sockeye run at the 600,000 level” if recent days counts were taken into account, Ellis told the Compact’s Oregon and Washington members. The Compact, made up of representatives of the Oregon and Washington department of fish and wildlife directors, sets commercial fishing seasons on the mainstem Columbia River where it represents the two states’ border.

The Compact on Wednesday approved mainstem commercial fisheries for non-tribal gill netters downstream of Bonneville, and for tribal fishers upstream. The state officials also held a joint state meeting, where they approved an extension of the “summer” season sport fishery for salmon on the Columbia mainstem.

A resurgence, particularly in the number of sockeye returning to the Okanogan River basin, has been experienced in recent years, with seven of the top 10 Bonneville Dam counts on record occurring this past seven years. Fishery officials attribute the improved returns to favorable ocean conditions that have prevailed in recent years, to increased hatcheries releases and to improved juvenile rearing habitat and freshwater migration conditions.

A "Fish-Water Management Tools” system developed specifically to manage water flows in the Okanagan River’s headwaters in British Columbia is believed to have helped. Since the FWMT was first used during the 2004-2005 season there have been no significant losses of sockeye or kokanee to drought and desiccation or flood and scour events.

In previous years, the drying out of sockeye redds and eggs in winter (as water was being held back to refill upstream reservoirs) and spring scour-flood events events that can serve to wipe out fry production were relatively common, researcher Kim Hyatt of Fisheries and Oceans Canada said back in 2010 following what was at that time a record return of sockeye.

Natural smolt production in the Canadian northern arm of Lake Osoyoos jumped from a historic average of about 300,000 sockeye salmon per year to a range of from three million to almost nine million since 2006, according to data compiled through 2010. Osoyoos, an Okanogan reservoir that stretches across the U.S.-Canada border, is a primary rearing area for the Okanogan sockeye stock.

Bonneville is the lowermost dam (located at river mile 146) in the Columbia River hydro system. All sockeye originate from upstream of Bonneville, with the vast majority coming from the Okanogan and Wenatchee river systems. Both empty into the Columbia in central Washington. A smaller fraction of the sockeye salmon return has roots in central Idaho’s Salmon River drainage. The Salmon flows into the Snake River, which is a tributary to the Columbia.

Ellis tempered his assessment with the fact that sockeye runs usually surge through the system quickly, and the numbers fall off quickly once the peak numbers have passed Bonneville.

The sockeye numbers passing over Bonneville built slowly in early June, but reached a daily count of 23,241 on June 21. Those counts have exceeded 20,000 every day since then except for a total of 19,087 on July 8 and Wednesday’s total of nearly 13,000. That roll included three days of 30,000 or more, including a high count of 34,549 on July 5.

It also “looks like Snake River sockeye are performing above the preseason forecast,” Ellis said. The forecast was for a return of 1,200 to the mouth of the Columbia River. But already 660 had reached the lower Snake River’s Lower Granite Dam as of Wednesday. Lower Granite is the eighth and final dam the Snake River sockeye must cross on their way to the Sawtooth Hatchery and Redfish Lake in central Idaho high country.

The Snake River sockeye swim roughly 500 miles up the Columbia and Snake, and have about 400 miles to go after crossing Lower Granite. As of midweek, none of the sockeye passing over Lower Granite had been sighted in the Sawtooth Valley. The first arrivals are expected within the next week or two.

The Snake River sockeye stock is listed as endangered under the Endangered Species Act. Most of the returning fish are the product of a captive broodstock program begun in the early 1990s in an attempt to avoid extinction of the species.

The Columbia-Snake river basin is the southernmost part of the sockeye's range. The vast majority of the run returns Wenatchee and Okanogan river basins and most of them, about 85 percent, return to the Okanagan. Almost all of the natural production is in the river just below McIntyre Dam.

McIntyre Dam is located Okanagan between Oliver and Okanagan Falls, British Columbia and is a part of the Okanagan Basin Lake Regulation System. The dam controls the water level of Vaseux Lake and the flows of Okanagan River between Vaseux and Osoyoos lakes. The dam was constructed in the1950s. Since that time, upstream fish passage has been impeded but recent years improvements have allow access to historic spawning grounds, including Skaha Lake.

For more on sockeye, see “Ocean conditions drove recent Columbia River sockeye booms” on the Northwest Fisheries Science Center website at http://www.nwfsc.noaa.gov/news/features/sockeye/index.cfm

Columbia Basin Bulletin The Columbia Basin Bulletin e-mail newsletter is produced by Intermountain Communications of Bend, Oregon and supported with Bonneville Power Administration fish and wildlife funds through the Northwest Power and Conservation Council's Columbia Basin Fish and Wildlife Program. Articles republished by The Dalles Chronicle with permission.

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