[1] Snake Fall Chinook Studies Get More Complicated
Scientists studying fall chinook from the Snake River have uncovered another new wrinkle in the various life-styles of that particular population, one that promises to make them even harder to study. In the past few years, researchers have found that many of the juvenile fall chinook overwinter in reservoirs, rather than migrate downstream by either barge or under their own power as subyearlings a few months after they hatch.
But now scientists have found out that even barging subyearlings past the dams doesn't guarantee that the fish will make it to the ocean that same year.
By sampling scales and reading growth patterns like tree rings, they have found that a good portion of returning adults hung out in the Columbia River below Bonneville Dam over the winter after being barged below the dams.
That was one of the messages delivered last week at the December meeting of the Northwest Power and Conservation Council, when federal researchers presented their latest findings. USFWS biologist Billy Connor was there again to explain the growing complexity, with some fish migrating as subyearlings, others later in the fall after spill at dams is stopped, and still others (yearlings) holding over in one reservoir or another for the entire winter, and heading to sea the following spring before April when PIT tag detection systems are turned on.
Conner's data showed that yearling fall chinook migrants are making up a growing percentage of overall returns. From 2002 to 2004, it doubled from 30 percent to 60 percent.
It's a phenomenon that seems to have grown as a consequence of effort to boost the ESA-listed fall chinook numbers by a supplementation program using fall chinook from Lyon's Ferry Hatchery, with another effort to develop a spawning population in the Clearwater River, which now accounts for about 30 percent of the fall chinook redds for the entire Snake population.
Scientists think the colder water in the Clearwater keeps many of the juvenile chinook there from reaching a size large enough to migrate as subyearlings, unlike most fish from the Snake. So they hold back and migrate later in the fall or overwinter, and head downstream in early spring, much larger than the typical subyearling.
Connor presented data that showed fall chinook transported in the summer from 2001-2004 made up about 25 percent of returning adults, but more than a third of those fish held over in the estuary and entered the ocean as yearlings. Nearly half of the fall chinook transported later in the year stayed in the estuary and made up about 30 percent of the adults sampled.
More than 40 percent of the sampled returns were made up of inriver migrants, but about three-quarters of that group didn't enter the ocean until they were yearlings.
Overall, Connor said yearling migrants made up 73 percent of the adults sampled from those three years. So where do they hang out before they finally head off to sea?
Just about everywhere in the hydro system, the scientists said, who had a hard time pinpointing their whereabouts because PIT-tag detection systems are turned off at dams in the wintertime because pipes might freeze. Researchers have had to use everything from pole and line to miniscule radio tags to track them down.
With the high-tech radio tags in Clearwater fall chinook, they found most of those fish don't travel very far during the summer when spill is added at dams on the lower Snake. In fact, most don't get as far as the first dam. About 80 percent of the Clearwater fish aren't even detected at the mouth of that river before fall sets in, still miles from the dam. About a third of the yearlings sampled as adults were never detected at all when they migrated through the hydro system.
NOAA Fisheries researcher Bill Muir explained why he thinks the larger, later-migrating fish have a survival advantage.
He said over 90 percent of the mainstem pikeminnow, a main predator of young salmon, were large enough to eat natural subyearling Snake fall chinook that had been transported, while only about 30 percent of the pikeminnow were big enough to eat late-migrating smolts from the Clearwater, and only about 20 percent of the pikeminnow were big enough to consume fall chinook that migrated as yearlings.
Once in the ocean, Muir said all of the transported subyearlings were still small enough to be vulnerable to predation by Pacific hake, which school in large masses off the West Coast during summer months, in the millions of tons. But, according to Muir, inriver migrating subyearlings grow large enough as they pass down the Columbia so that most hake have to pass them by.
By the time they make it to the ocean, both the late-migrating Clearwater fish and yearling migrators are too big for the hake to take.
"I think this goes towards explaining why we can load fish on a barge," said Muir, "and get around the substantial mortality that occurs for dam passage by going through the entire hydropower system, which is very substantial for fall chinook salmon compared to spring migrants, but yet we don't necessarily see a great benefit from transport when adults return."
Muir said return rates for transported and inriver-bypassed fall chinook were nearly identical, while the smolt-to-adult return rate for the yearlings was nearly three times better (1.35 percent compared to transported at .51 percent, or bypassed at .56 percent).
The complicated life histories of the Snake fall chinook has raised questions about the value of court-ordered summer spill at lower Snake and McNary dams and whether it is improving survival. Before Judge Redden's 2005 order, spill was stopped altogether at four of the dams to maximize barging smolts.
However, scientists like Muir say that to estimate the real value of barging fall chinook, any new study must account for the life history diversity of the population, or management decisions could be made counter to recovery.
The researchers said that they are designing more new research to study the effects of spill. For now, they said the spill probably has a positive effect on Snake-origin fish that migrate in the summer, but not for Clearwater fish that generally migrate later in the fall or hold over in one of the reservoirs until spring.
However, it may be tough to get a handle on the situation anytime soon. Muir said returns to Lyons Ferry Hatchery were less than anticipated, which may make it difficult to provide enough smolts for next year's research needs.
Meanwhile, annual returns of wild fall chinook have grown into the thousands from the low of 79 fish in 1990, when only 78 wild fall chinook were estimated to have returned to Idaho. Their numbers had declined steadily since the 1960s, after three-fourths of their habitat was blocked by construction of Idaho Power's Hells Canyon Complex.
Connor told NW Fishletter that members of the technical recovery team dealing with interior Columbia ESA stocks, told him that the Snake fall chinook had the best shot at recovery of any ESUs they are dealing with. -Bill Rudolph
[2] BPA Says Latest Comparative Survival Study Incomplete
The Bonneville Power Administration has weighed in with a dozen pages of comments taking issue with the latest draft of the Comparative Survival Study, an ongoing report that has stirred controversy since its beginnings ten years ago. The controversy continues, and has been a major bone of contention.
CSS has been funded by the power-marketing agency since it started, much to the chagrin of some ratepayer groups. In fact, sources said that several individuals on the utility side of regional fish politics strongly urged BPA to file the comments.
The authors of the CSS, which include state, tribal and USFWS staffers, and led by Michele DeHart, director of the Fish Passage Center, have been under scrutiny since federal scientists and BPA raised significant questions over the value of the work and questioned whether the study should continue to be funded.
In 2005, BPA said the CSS upriver-downriver comparison intended to extract hydrosystem effects "has been misguided from conception." NOAA scientists said the CSS treatment of upstream/downstream stocks seemed "particularly biased."
But funding has been continued for the next six to nine months to allow CSS writers to complete a report that covers their 10-year-long investigation into survival of PIT-tagged wild and hatchery spring chinook and steelhead.
The draft 2006 CSS report was released for public comment in late October. BPA has weighed in again this year, though NOAA Fisheries did not comment on the latest draft at all.
After 10 years of paying for the CSS, BPA is still asking its authors to provide the underlying statistical framework and "explain how stated assumptions are used throughout the report."
BPA says that the CSS report has left out several important elements in its analysis that, if added, "could likely explain differential survival among PIT-tagged populations, particularly the factors that could help explain any difference in SARs [smolt-to-adult return rates] of up and down river stocks."
The debate over 'D'--that aspect of juvenile fish mortality that is "delayed" and occurs outside the hydro system--has been going on for years, ever since it was hypothesized in the mid-1990s during the PATH process, a regional and sometimes testy regional collaboration studying various aspects of the salmon recovery effort in the Columbia Basin.
Many state and tribal participants in PATH, plus USFWS biologists, supported the notion that barged and bypassed fish eventually died off at higher rates than fish that migrated inriver, which they said suffered ill effects from hydro passage as well. Confusion and years of wrangling ensued, leading to the concept of "differential delayed mortality," which proponents say shows upriver stocks died off at higher rates.
The controversy continues, and has been a major bone of contention during development of the latest fish passage survival model [COMPASS] being used in the hydro BiOp remand. Computer modelers and other biologists met recently in Portland to take another look at it, in the presence of the independent science board.
In the letter to the Fish Passage Center, Bob Austin, BPA's deputy director for fish and wildlife, cited previous comments from the science board that echoed their own call for "additional supporting data" and more descriptions of CSS methodology to allow a "disinterested third party to reproduce the analysis and conclusions."
The latest draft CSS report still clings to annual 'D' estimates for various stocks, despite criticism last year by both the feds and BPA, who said closer investigation of PIT-tagged fish has shown that survival to adulthood varied widely from one week's juvenile migration to another. The general implication was that transported fish survival improved greatly later in the spring, which suggested that ocean entry timing and fish size play important roles in ultimate survival.
But the latest CSS report says its authors found little evidence that size differences or entry timing between upstream and downstream stocks played much of a role in upstream/downstream comparisons.
NOAA scientists, in last year's comments, said they had evidence that smaller fish tended to take bypass routes at dams, (and then be barged), and that hatchery PIT-tagged fish returned at lower rates than the run at large. Furthermore, they had taken issue with comments in last year's draft CSS report that barging wild spring chinook showed little or no benefit for wild spring chinook, when CSS' own data showed benefits in five out of ten years.
The CSS authors added a statement to their conclusions in the final 2005 CSS to reflect the feds' concern. But in this year's draft, the statement about barging benefits for wild spring chinook was missing altogether.
The feds won't be calling CSS authors on the issue this time around, since they didn't send comments.
But results from their own studies put barging springers from Lower Granite Dam on the Snake River in a good light. Last month, NOAA Fisheries researcher Doug Marsh reported that returns from the 2003 outmigration outperformed inriver migrating (non-detected) chinook by 2.64 to 1.00. Barging from Little Goose showed benefits as well, with transported fish doing 60 percent better than inriver migrators.
The final 2006 CSS report was released Dec. 12, which included responses to some BPA comments, mainly in regard to statistical issues. CSS authors said some other BPA recommendations would be addressed in their upcoming "synthesis" report or other future analysis. The final 2006 report didn't include any comments about the benefit of barging wild chinook like last year's final report. -B. R.
[3] States, Politicians Gang Up On Sea Lions
After several years of stepping up harassment of marine mammals feasting on ESA-listed spring chinook at Bonneville Dam, Washington and Oregon have finally thrown in the towel. Both states have made formal applications to the federal government for the authority to kill the pesky sea lions, which are protected under the Marine Mammal Protection Act.
Last year, marine mammals chewed their way through about 3 percent of the spring run and were cavorting in Bonneville's fish ladder, much to the pleasure of TV newspeople, despite heroic efforts by the Corps of Engineers to outsmart the hungry critters. The Corps put up bars, shot firecrackers, and even tried "underwater acoustic deterrents" to keep the hungry pinnipeds away from the migrating fish.
Marine mammal numbers on the West Coast have tripled since falling under the protection of the 1972 Marine Mammal Act. The California sea lion population is now estimated at about 250,000. Steller's sea lions make up another 31,000, and the harbor seal population in Oregon and Washington adds up to about 25,000 more pinnipeds.
Biologists say the predation problem at the dam has increased more than sevenfold in recent years. Meanwhile, another thousand or so sea lions cruise the lower river every spring, eating an unknown amount of salmon and sturgeon. Biologists say sea lions eat about six salmon a day if fish are available.
But the process to get legal authority to kill a few sea lions may take years, and must include a review by a task force represented by states, feds, tribes, scientists, and conservation and fishing groups
That lengthy possibility propelled three Northwest politicians to introduce a bill in October that would allow the Secretary of Commerce to issue permits to allow the "lethal taking" of up to 10 sea lions by next spring if other measures don't work.
Washington's Doc Hastings (R), Brian Baird (D), and Norm Dicks (D) crafted the bill in such a way that up to six permits could be issued. The bill also says that the total number of sea lions that might be killed could not exceed one percent of "the annual potential biological removal level of California sea lions."
Baird said the bill is a tool to use after all other options have been exhausted, "and it will send a strong message that the all-you-can-eat salmon buffet at the Bonneville Dam is closed."
The states' application calls for removing a limited number of California sea lions within six miles of the dam, along with other marked animals that have been seen there eating salmon.
"Lethal removal is a management tool we prefer not to use, but one that may be necessary to restore balance to the Columbia River ecosystem where threatened and endangered stocks of salmon and steelhead are being preyed on by a healthy and growing population of California sea lions," said Guy Norman of WDFW's southwest regional office.
Last month, at the Corps of Engineers annual research review in Portland, scientists reported on studies undertaken in recent years dealing with the sea lion problem.
In one study, radio-tagged salmon were tracked to see if hazing activities designed to deter the marine mammals would have adverse affects on fish passage. Salmon actually showed a proclivity for entering fishways while hazing was going on and while the "acoustic deterrent device" was in operation, though the researchers said it was not a statistically significant difference.
This year, sea lions saw both fireworks and rubber bullets headed their way, along with a 205-decibel 15 kHz frequency sound at fishway entrances. Other agencies manned boats to haze the mammals up close.
But overall, this year's hazing efforts kept the predation level similar to that observed in 2005 when 3.4 percent of the run was estimated to have been intercepted by the salmon-loving sea lions, though down a bit to 2.8 percent.
The Corps said about 72 California sea lions, 10 Steller's sea lions and 3 harbor seals were documented in 2006. With an average of about 27 marine mammals around the dam on any given day, the researchers found that hazing didn't make any difference in those numbers, but the grating installed at fishways kept most sea lions from entering.
Their conclusion so far? Non-lethal deterrence has proved ineffective in reducing predation, but more intense hazing efforts may keep sea lions away from fishway entrances.
Last spring, about 96,000 spring chinook were counted at Bonneville Dam. Close to 3,000 of them were estimated to have been eaten by sea lions. About 8,800 upriver springers were caught in tribal fisheries, and about 1,900 in non-Indian sport and commercial fisheries. -B. R.
[4] Forecasters Say 2007 Spring Run Should Be Down, But Redfish Sockeye Up
Columbia Basin harvest managers have pegged next year's upriver spring chinook run in the Columbia River at a mere 78,000 fish. That is about 10,000 fish below their forecast for the 2006 run, which came in significantly better, at 88,400, a 50-percent boost.
They have estimated that more than 13,000 wild spring/summer chinook will be part of that run, slightly lower than last year's forecast of 14,600 fish. More than 21,000 wild Snake springers (to mouth of Columbia) actually showed up, about 50 percent above the forecast.
The managers had lowballed last year's upriver Columbia summer run as well, at 49,000 fish, but more than 76,000 actually showed up. This year, they expect about 45,600.
For the upper Columbia springers, they estimate about 9,200 fish returning, with 1,200 of them wild. Last year, the run came in 36 percent better than expected, at 17,100 fish.
The Willamette should produce about 52,000 spring chinook next year, they said, with the Cowlitz, Kalama and Lewis rivers producing 16,300 fish, and the Yakima around 6,100 spring chinook. Last year, the Yakima produced about 6,000.
For 2007, the managers said about 37,000 sockeye are expected to return to the Columbia, with most heading for the upper Columbia. But they estimated that about 300 ESA-listed Redfish Lake sockeye would enter the Columbia in 2007. In 2006, they estimated the Redfish Lake return at 21 fish, and revised it upwards to 79 fish by the end of the season. -B. R.
[5] Feds Building New Fish Forecasting Tool
Scientists from NOAA Fisheries say ocean conditions have improved since last year, which should boost coho and chinook returns in the Columbia River over the next couple of years. They have been monitoring conditions off the West Coast, looking at water temperatures, salinity, upwelling and larger scale effects like El Nino conditions, along with biological indicators like plankton growth that govern the food chain, predation by hake and birds, and trawl surveys of juvenile salmon. It's part of a new push to develop a predictive tool for estimating salmon runs.
John Ferguson, director of the Science Center's fish ecology division, said his group was excited about the new tool. The scientists think it will significantly improve their ability to forecast salmon runs.
"Early this year, we observed a lot of upwelling, which indicates in general that we'd expect higher salmon runs compared to recent years," Ferguson said last week in a press release. But conditions deteriorated in mid-May and didn't improve until after mid-June. He said that could mean poor returns for coho in 2007.
The feds say the new tool could help forecast coho returns a year in advance and chinook two years in advance.
In 2005, NOAA Fisheries researcher Ed Casillas reported the lowest numbers of juvenile chinook and coho they had seen since their trawl surveys began in 1998. Consequently, they expected poor coho returns this year.
But, surprisingly, the coho numbers came in better than state and tribal fish managers had expected. In a later November post-season report, they said the preseason estimate of 257,000 Columbia River coho (190,000 early, 67,000 late run) was boosted by more than 30 percent on Nov. 27 to 340,000 (220,000 early, 120,000 late).
So far, the feds are only making qualitative forecasts. A "good" forecast is relative to returns over the past 10 years.
NOAA's Casillas said the feds' tool is only as good as its database, which doesn't include that many years. "Time will tell how useful it is," he told NW Fishletter. He said the physical and biological conditions monitored by the predictive toolmakers will soon be available on a new website. For now, much of the information is available in a recent report on ocean conditions and salmon survival and a new home page has been developed to access that information and updates. -B. R.
[6] El Niño Still Growing
The temperature anomalies in the equatorial Pacific are growing, said the National Weather Service's Climate Prediction Center, in a Dec. 7 El Niño update. They now expect the warming phenomena to last through next May, peaking in December and January.
Despite record rainfall in much of the Northwest last month, many parts of the region should still expect a warmer and drier-than average period between January and March.
The Australian Bureau of Meteorology reported that in the latest survey of a dozen international computer models, five of the twelve models predict warm conditions, consistent with an El Niño event, continuing until April 2007, with only two of these showing El Niño conditions persisting until July 2007. Their own model shows a steady decline in warm conditions.
A series of oceanic heat waves have moved eastward toward South America. The largest was expected to reach the coasts of Ecuador and northern Peru by mid-December where substantial warming of coastal waters is expected.
Meanwhile, in the Pacific Ocean off Washington, water temperatures are about average, with a large area off central Oregon that is a degree or two F below average for this time of year.
On Nov. 16, the Climate Prediction Center called the El Niño event "on the border between weak and moderate--since the coupling of the unusually warm SSTs [sea surface temperatures] near the date line with the atmosphere in the tropical Pacific has not yet become fully established. This coupling is expected to occur during the next month or so."
On Dec. 6, the Aussies said this coupling had occurred.
"The 2006/07 El Niño is entering its mature phase, when the Pacific ocean temperatures, winds and cloud patterns reinforce each other. Computer model guidance continues to suggest that Pacific Ocean temperatures, and hence the El Niño, may peak around January or February 2007. This timing would be consistent with the breakdown of past El Niño events."
On Dec. 20, the Australians said there were a few signs the event had already started to weaken.-B. R.
[7] Study On Economics Of Dam Breaching Takes Another Hit
A three-year old letter surfaced last week that undercuts "Revenue Stream," a recent report by environmental groups claiming the region could save billions of dollars by removing the lower Snake River Dams and replacing the barge industry with mostly rail lines.
The January 2004 letter from BST Associates to American Rivers' Northwest regional office complained that the results of a BST study commissioned by American Rivers and other groups were misrepresented in a press release that minimized impacts and ignored "many cautions in the body of the report."
BST said eliminating barge transportation on the Snake would yield a less efficient system, and replacing it with rail would be fraught with problems caused by capacity constraints.
Further, even if there were interest in expanding the rail-based short-haul business to overcome the constraints, higher rates would likely result because of the huge capital costs of the expansion, the consultants said.
The letter also said it was uncertain whether alternative transportation systems could accommodate diverted cargo volumes.
These findings are a far cry from those characterized in "Revenue Stream," which said, "recent studies" found that the barge navigation channel created by the dams "could be affordably and effectively replaced by upgrading the Northwest's railroad lines (see NW Fishletter 223). The report cites the BST study in a footnote.
BST's letter said rail constraints in Washington, along with more passenger trains along the I-5 corridor, were straining the system's capacity. "Under the circumstances, it may be prudent to divert more cargo from rail to barge to alleviate congestion," it said.
Brian Willingham, BST's senior economist, told NW Fishletter that the same conditions exist today, nearly three years after the letter was written. He also said his firm was not even aware of the new report by enviro groups.
The original BST study concluded that switching from barge to rail could cost more than $1.4 billion. "Revenue Stream" pegs the cost of upgrading railroads between $18 million and $231 million.
At the time, BST asked American Rivers to post its letter on the conservation group's website, but in its response, the group said it would be 'unnecessary" and "inappropriate" to do so.
At last week's meeting of the Northwest Power and Conservation Council, members voted to have the Revenue Stream report reviewed by the independent panel of economists that have performed such tasks in the past. Their review is expected to be finished before the council's next meeting in January. -B. R.
[8] Hydro BiOp Remand Extended At Least Through Next July
Oregon District Court Judge James Redden last week granted a motion by the federal government to extend the timeline for completion of the hydro BiOp from Feb. 7 to July 31, 2007.
Federal attorneys said the extra time was needed for action agencies to prepare a biological assessment, NOAA Fisheries to write the draft BiOp and share it with fish and wildlife managers before a final version would be completed. They said they might even need more time.
Plaintiff environmental and fishing groups did not object to the extension. In fact, they said it was likely that even more time would be needed for them to prepare an adequate response to the draft BiOp.
Redden also extended the timeline for the feds to complete their next status report on the remand process to Feb. 2, 2007. Last Friday, the judge issued a scheduling order that calls for any motions for injunctive relief to be filed by January 19. Some parties to the litigation have expected that plaintiff environmental and fishing groups would ask for more changes to hydro operations.
It was reported that some plaintiff groups may ask for changes to reservoir operations that lower elevations to improve water particle passage time, which they say improves fish survival. In June, 2005, they won a partial victory by getting Redden to agree to add $67 million in spill at dams to help ESA-listed fall chinook, but the judge balked at ordering more flow augmentation, saying that the science was still unclear about its benefits for fish. -B. R.
[9] Grant PUD Sets Vernita Bar Flows For Fall Chinook
Grant County PUD has announced that the utility would maintain a 70,000 cfs minimum flow in the Columbia River through the Hanford Reach for the next seven months to protect fall chinook redds.
PUD biologists estimated that 40,000 to 50,000 fish spawned in the reach this year. They said it's lower than recent years, but only a bit less than the 10-year average.
Their numbers jibe with information released by Columbia Basin salmon managers, who estimated that the upriver bright stock returned slightly less than the predicted return (to river mouth) of 249,000 fish. With jack returns similar to the 2005 run, they expect that the 2007 Hanford run could be less than 200,000 fish.
Overall, the 2006 total fall chinook run in the Columbia came in slightly under their 460,000-fish prediction. They said next year's return could be less than 400,000. -B. R.
[10] Corps To Be Sued Over Libby Dam Operations
The Center for Biological Diversity and the WildWest Institute announced Dec. 13 they will sue the US Army Corps of Engineers for not following the agency's interim water storage plan known as VARQ at Montana's Libby Dam last spring. The Corps has admitted that if it had followed VARQ procedures, large amounts of water would not have been spilled after a late-season rain event caught reservoir control operators off guard. The Center says the large amount of spill harmed bull trout and other resident fish by giving them gas bubble disease.
"Harm of Bull Trout resulting from failure to follow a biological opinion amounts to criminal activity on the part of the Corps and the top-level bureaucrats that elected to ignore measures to protect the sturgeon and other fish," said Noah Greenwald, a conversation biologist with the Center.
The CBD and WWI are already headed for court to challenge the biological opinion written by the US Fish and Wildlife Department, with support from the state of Montana, though the state is opposed to spill, while the environmental groups are not totally opposed to spill.
Greenwald said the operation of Libby Dam is causing the Kootenai River White Sturgeon's decline to extinction because river flows have been drastically reduced since the dam was completed in 1974. Earlier biological opinions required consideration of the addition of more turbines at Libby so boosted flows wouldn't have created gas problems for fish, but the latest BiOp calls for using the spillway to pass increased flows.
The Kootenai Tribe has sided with the USFWS in the BiOp litigation. -B. R.
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