[9] BPA Says FPC Study Short-Changes Benefits Of Fish Barging
The Bonneville Power Administration said the latest draft of an ongoing study of fish survival in the Columbia Basin by the Fish Passage Center suffers from serious problems. The study has tagged hundreds of thousands of hatchery fish and compared passage routes and survivals from different facilities, both upriver and down, since 1996.
The study, which has been funded by the power marketing agency at about $1 million annually, has been mired in controversy since its very beginnings when a special panel of independent scientists was convened to assess its potential value. The panel OK'd the study, but noted serious shortcomings in the study design it said could be worked out later. It seems that many of those old issues are coming back to haunt the FPC's latest results.
In comments sent to the Fish Passage Center last week by BPA Fish and Wildlife director Bill Maslen, the agency says the comparative survival study, under the supervision of FPC director Michele DeHart, suffers from a serious drawback--the lack of an underlying statistical model. Without it, smolt-to-adult ratios for transported fish are negatively biased. However, estimators for control inriver fish are unbiased, "which means that all transport/inriver ratios (also known as transport benefit ratios) i.e., T/C are incorrect. This is a serious problem affecting many of the results presented throughout this report and minimized the benefits of transportation."
The BPA letter says the bias is apparent when compared to empirical results. It points to the 2003/2004 CSS report that included a table which showed that CSS estimates were often low by a factor of 2. It also noted that the table was omitted from the latest CSS draft.
But even with the negative bias against transport, Maslen said the latest CSS draft demonstrated "overall" benefits of transportation. In the drought year 2001, CSS noted T/C ratios from 5.32 for hatchery chinook (Catherine Creek) to nearly 60 for hatchery steelhead. Wild chinook showed huge benefits as well that year, with a T/C ratio of nearly 9, while wild steelhead showed a T/C of 37.
In non-drought years, Maslen said the CSS study used a geometric means construct to figure average survivals from year to year, which always will be less than the arithmetic average. "A re-analysis with proper and unbiased estimates of SARs for the transported smolts will result in higher and more realistic estimates of the benefits of transportation," says the BPA letter.
The focus on delayed mortality is also misguided, according to the BPA comments, because the effectiveness of transport is gauged better by T/C ratios. The years-long debate about whether barging fish causes later mortality misses the fact that barged fish, once released below Bonneville Dam, are still at risk from poor condition or disease that would have killed inriver fish during their migration through the hydro system.
The letter also takes issue with another point that fish agencies and tribes have argued about with federal agencies for years. "The upriver-downriver comparison of Chinook salmon stocks to extract hydrosystem effects has been misguided from conception," says BPA, noting that data from the CSS shows related stocks from nearby hatcheries don't even show similar SARs, and data from code-wire tagging shows different stocks have very different ocean migration patterns and are intercepted in fisheries differently.
BPA says earlier CSS comparisons confirm this because, "Initially, the study started with multiple downriver stocks, but these hatcheries have been reduced to only the Carson NFH, when the other hatcheries had SAR values less than upriver hatcheries. If investigators eliminate all the information that does not conform to their conceptual model, as in the case of the upriver-downriver comparison, you are often left with nothing but coincidences or wishful thinking."
BPA said the greatest contribution of the CSS has been the release of PIT-tagged smolts for study. "However," it said, "the data interpretations in the CSS report are technically flawed, resulting in skewed interpretations that minimize the benefits of transportation and the return rates of salmonids.
The future of the comparative survival study is unclear at the moment since the Fish Passage Center's funding has been jerked by Congressional action, after Sen. Larry Craig (R) of Idaho inserted language in the energy and water appropriations bill that said BPA could no longer pay for the Center's operation. The bill has passed Congress and has been sent to the President's desk for signing. It orders BPA and the Northwest Power and Conservation Council "to ensure that an orderly transfer of the Fish Passage Center functions (warehouse of smolt monitoring data, routine data analysis and reporting and coordination of the smolt monitoring program) occurs within 120 days of enactment of this legislation. These functions shall be transferred to other existing and capable entities in the region in a manner that ensures seamless continuity of activities."
Critics, especially utilities, have complained about the advocacy role by FPC personnel for years, but state fish agencies and tribes had always been successful at fending off earlier attempts to reduce the FPC's power in regional fish politics. Environmental and fishing groups who have successfully sued to throw out recent hydro BiOps have depended on FPC analyses in their arguments, and have cited the latest CSS draft in their latest filings to change interim dam operations. -B. R.
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