latest estimate of sockeye salmon mortality in the upper Columbia River Basin,
mostly due to high water temperatures, is 80 to 90 percent of a summer return
run of nearly a half million fish, according to NOAA Fisheries.
percent is the best for the upper Columbia River,” said NOAA public affairs
officer Michael Milstein. Most sockeye migrate into the upper Columbia and a much
smaller proportion move into the Snake River Basin.
way, Milstein said, the proportion of mortality appears to be the same for
sockeye salmon that have been trying to migrate throughout the greater Columbia
are either parked in the river waiting for better conditions, or they are dead
and dying,” Milstein said on Thursday.
know that a half million sockeye are in the river, because a half million of
them passed through Bonneville (Dam), and we know that only a small portion of
them were destined for the Snake River,” he said, adding that only 10 percent
have passed through Lower Granite Dam, just shy of the Idaho border.
variety of news reports from earlier this week discussed mortality rates for
sockeye salmon to be roughly half of the summer return run, but those estimates
have been increased, said Milstein,
who emphasized that mortalities are difficult to estimate.
estimates aside, Milstein said 2015 has been a remarkable year for dry, hot,
early runoff conditions in the Pacific Northwest.
everything that I am aware of and can compare … there hasn’t been a year like
this year before. We are seeing August (streamflow) temperatures in June,” he
noted that there were drought conditions for the Columbia Basin in 2001 that
adversely impacted streamflow volumes, “but we didn’t have the same temperature
problems in the water that we see this year.”
extreme nature of the situation has prompted fishing regulation changes from
the Washington Department of Fish and Wildlife that took effect after sunset on
July 26. All sockeye harvest was banned from Rocky Reach Dam to Chief Joseph
water temperature in the Columbia River resulted in higher than expected
mortalities of sockeye salmon returning to the Okanagan River,” a press release
from the department states. “Fish destined to return to the Okanagan River are
staging in the Columbia River above the Rocky Reach Dam. This fishing closure
for sockeye salmon is needed to protect these fish from harvest and allow them
to migrate to their spawning grounds when water temperatures improve.”
of Thursday (July 30) 508,734 sockeye had been counted passing over Bonneville
Dam; 426,630 at The Dalles Dam; 361,342 at John Day Dam; and 274,731 at McNary
did open Lake Wenatchee for sockeye fishing beginning Thursday, July 30.
on current passage over Tumwater Dam, at least 30,000 sockeye are projected to
enter into Lake Wenatchee. This provides at least 7,000 sockeye for harvest
above the natural spawning escapement goal of 23,000 fish,” said WDFW.
another 1.8 million salmon and steelhead are now returning to the Columbia
River, with the majority headed for the Basin’s (at least for now) low, warm
flows above Bonneville Dam.
River fisheries managers are expecting a 2015 fall chinook return of 925,300
fish, which would be 80 percent of the 2014 actual return (1,159,100) and 147
percent of the 2005-2014 average return (631,200).
chinook generally enter the Columbia River from late July through October with
abundance peaking in the lower river from mid-August to mid-September and
passage at Bonneville Dam peaking in early to mid-September.
2015 forecast for the summer steelhead return to Bonneville Dam is 312,200
upriver fish, including 13,400 Skamania stock (4,100 wild), 257,700 Group A
stock (95,400 wild), and 41,000 Group B stock (11,700 wild). Overall, the
forecast is 90 percent of the 2005-2014 average of 347,500 fish. The Skamania
and Group A forecasts are 103 percent and 105 percent the 2005-2014 respective
average returns. The Group B forecast is 80 percent the 2005-2014 average return.
majority of steelhead passage at Bonneville Dam occurs during July through
2015 forecast for the Columbia River coho return is for a strong return of
539,600 adults, which includes 377,300 early stock and 162,300 late stock. The
forecast is 117 percent of the 2005-2014 average of 459,800 fish. The
individual forecasts for early and late stock coho are 131 percent and 95
percent of the 2004-2013 averages, respectively. Bonneville Dam passage is
expected to be 190,500 adult coho, which represents 65 percent of the
forecasted total ocean abundance of Columbia River coho destined for areas
upstream of Bonneville Dam.
stock coho enter the Columbia River from mid-August to early October with peak
entry occurring in early September. In the ocean, early stock coho tend to
remain near the Oregon and southern Washington coasts and primarily migrate
southward from the Columbia River, and are therefore referred to as Type S.
Late stock coho enter the Columbia River from mid-September through December
with peak entry occurring in mid-October.
more see the July 14, 2015 Joint Staff Report: Stock Status and Fisheries For
Fall Chinook Salmon, Coho Salmon, Chum Salmon, Summer Steelhead, and White
Sturgeon by Joint Columbia River Management Staff, Washington Department of
Fish and Wildlife, Oregon Department of Fish and Wildlife at http://www.dfw.state.or.us/fish/OSCRP/CRM/reports/15_reports/2015falljsr.pdf