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NOAA'S Lohn Updates Power Council on
Upcoming Spill Evaluation, Hints at BiOp Changes

by Bill Rudolph
NW Fishletter, December 19, 2003

Regional NOAA Fisheries Administrator Bob Lohn has suggested that major changes may be on the way for the new hydro BiOp. With the current document in remand and being rewritten, flows to augment passage of salmon listed for protection under the Endangered Species Act may be reduced, Lohn suggested at last week's Northwest Power and Conservation Council meeting. He also said the agency will take a serious look at the biological value of summer spill.

Lohn said the spill evaluation could go two ways. Researchers could either pit-tag one million to two million fish and measure changes in system survival from adjustments to the summer spill regime now in place at four dams. Or, they could measure survival of smaller groups of fish by using radio-tags at specific projects.

The small-group survival approach to assessing the safest passage for summer migrants would require a prohibitively long study period to reliably discern the small, 3-percent difference expected between spill passage on the one hand, and bypass or turbine passage on the other. Lohn said that up to 600 years of observations would be needed to meet an 80 percent confidence level for the result.

"Which is a polite scientific way," Lohn said, "of telling us that we are unlikely to get system-wide survival data at that level of accuracy capable of measuring those nuances in a time that's going to be important for the decision we need to make."

In contrast, Lohn said radio tags would be ready for use by next summer to begin spill evaluations at the four dams in question--one in the lower Snake and three in the mainstem Columbia River. But Lohn cautioned that such research had its own drawbacks. Researchers must use larger-than-average fish to install radio tags, which leads to an assumption that these fish represent the run at large. Also, tagging fish in late July and August, which has not been done before, can lead to much higher handling mortalities from the warmer summer water.

But even with these limitations, Lohn said the approach could provide valuable information about comparative survivals from different dam operations. And to help get a handle on survival impacts of proposed operational changes, Lohn said NOAA Fisheries' SIMPAS passage model would be updated to include the latest results in fish survival.

Meanwhile, a policy committee is developing biological "offsets" for any losses that reduced summer spill might cause in ESA-listed stocks and other runs, like the recently spectacular Hanford Reach fall run.

One suggestion calls for expanding the current BPA program that offers a bounty for salmon predators like northern pikeminnow, a project the Council itself tried to cut in half earlier this year. Estimates of benefits from such actions are expected in the next few weeks, and any cost savings from spill reduction could be used to expand some offset programs, Lohn said. Federal executives were scheduled to meet Dec. 12 to discuss the evaluation and potential offsets, but were not ready to settle on any particular alternative. Lohn said treaty tribes would be consulted before a final decision is reached.

Washington power council member Larry Cassidy voiced concern about fish from unlisted salmon runs that enter the Columbia below McNary Dam and therefore cannot be barged.

"I'm assuming that we are going to damage fish," he said. Cassidy pointed out that nobody knows how many fish are in the river in August, when spill may be reduced. Until that is determined, there is no way to calculate reasonable mitigation.

Lohn said precise estimates of run passage are not reliable, but "you could develop a pretty good sense of roughly how many fish are in the river at that time, and how many are likely to be affected."

Cassidy pointed out that losses would be much more than the 15 or 20 ESA-listed Snake River fall chinook that Council staffer Bruce Suzumoto had estimated from reducing summer spill.

"You're talking a minimum of 6,000 and some tribal reports show as many as 25,000 adults," Cassidy said. "We don't know where that number is, but it's a significantly greater number. We see too many headlines that say, 'Summer spill is only about 15 fish.'" The tribal analysis to which Cassidy referred has never been released for public review, and was calculated with early estimates of delayed mortality for barged Hanford Reach fall chinook from the PATH (Plan for Analyzing and Testing Hypotheses) process.

Montana council members, who have pushed hard for an evaluation of augmented flows because it depletes two of the state's big reservoirs, seemed pleased with Lohn's remarks. Responding to a question from Montana's Ed Bartlett, Lohn said NOAA's main focus is ecosystem integrity. "It makes very little sense to be damaging one ecosystem to focus solely on benefits in another," Lohn said.

Lohn said his agency will release updated white papers next month (drafts should be available by Dec. 23 at ) that will include the latest results from flow and survival studies, in both the Columbia and Snake, including several more years of data than earlier papers evaluated. He also mentioned recent work by USFWS researcher Billy Conner, who has been trying to determine whether higher flows help fall chinook through the lower Snake. The issue is confounded because improved survivals also correlate with increased turbidity and temperature and reduced travel time.

Lohn said Conner's results suggest that temperature is a driving factor in the fishes' survival. "Does adding more hot water help fish at all?" he asked rhetorically, indicating the federal agency is seriously questioning the value of adding more water from the upper Snake to aid summer fish passage.

Environmental groups have said recently they will go to court to ensure that the old BiOp target flows are met. But with a new draft BiOp expected by March, those targets may change.

Bill Rudolph
NOAA'S Lohn Updates Power Council on Upcoming Spill Evaluation, Hints at BiOp Changes
NW Fishletter, December 19, 2003

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