How Can Dams in Eastern Washington Affect Puget Sound Orcas?

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By Howard Garrett*

As mentioned in an earlier post, on Nov. 23 Judge James A. Redden held a hearing in Portland that could lead to implementation of the Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp) within a few months. The BiOp, written by the Bush administration, would allow dam operation until 2018 despite the dams’ devastating effects on endangered salmon. Along with salmon disaster, the BiOp, if not dramatically improved, will likely lead to increased mortalities of endangered Southern Resident Killer Whales, which depend on some of these same salmon for their survival. At only 87 members currently in this extended orca clan, significant losses could reduce their numbers beyond the point of no return.

A biological opinion is required when federally licensed or federally funded activities – in this case, federal hydropower operations on the Columbia and Snake Rivers – might harm a species listed under the Endangered Species Act as endangered or threatened. It is supposed to outline how the responsible agencies will adapt the activity to avoid harming the species. The ESA list includes 13 distinct populations of salmon that spawn in the Columbia and Snake River watersheds, including some chinook runs that are essential for survival of the endangered Southern Resident orca population.

The Snake River is the Columbia’s largest tributary. Its watershed drains nearly 110,000 square miles of wilderness, including the best and highest chinook salmon spawning habitat in the lower 48 states. As many as six million spawning chinook used to return to the Snake each year. And chinook, as explained in How Many Fish Do The Orcas Need, are the fish upon which Southern Resident orcas depend.

But Snake River chinook?

Youngest calf ‘Star‘ J46 swimming with mom ‘Polaris’ J28 and (probable) cousin J34 in Admiralty Inlet 12/5/09. (Photo by Howard Garrett)

Southern Resident orcas tend to reside in the Salish Sea only between May and October (except for a few quick trips back into Puget Sound). The rest of the year, they head out to coastal waters. Their movements are not well known, but scientists believe they forage along the coast, largely for spring/summer and fall Chinook from the Columbia/Snake, Klamath, and sometimes the Sacramento rivers to get them through the winters. The Columbia/Snake Chinook are close to their home waters and were historically the most abundant.

Since the Corps of Engineers completed the fourth of four dams on the lower Snake River in 1975, wild Snake River spring/summer Chinook have not once reached their extremely low recovery targets (the number of spawning salmon necessary to avoid extinction), which must be met for eight consecutive years before the species may be considered recovered. Fall Chinook have barely met recovery targets some years, but that target is low and the species remains threatened and teetering on extinction.

Most scientists agree that removal of the four lower Snake River dams would result in a big rebound of wild salmon that spawn there, along with a full range of wildlife (see below) and Puget Sound’s resident J, K and L pods. Among many examples are these:

* “In contrast to the uncertainty of success from the removal of hydro projects in other portions of the basin, the benefits to Snake River stock survival and recovery would be assured with the removal of the lower four dams on that system…” Western Division, American Fisheries Society. The Western Division of AFS represents some 3500 fisheries biologists.
* The 1998 PATH (“Plan for Analyzing and Testing Hypotheses”) report concluded that within 24 years, partially removing the lower Snake River dams has an 80 percent and 100 percent probability, respectively, of recovering Snake River spring/summer chinook and fall chinook. The report also stated that fish barging programs, either current or maximized, have less than a 50 percent probability of recovery. Regardless of assumptions made or model used, dam removal was always the highest-ranked recovery option, and the one with the least amount of outcome uncertainty. The PATH team included some two dozen scientists from government, academia, and independent institutions.
* By the same token, leaving the dams in place is a losing strategy: “Based on our assessment, a recovery strategy for Snake River spring/summer chinook salmon that relies largely on stream restoration to mitigate for known mortality attributable to current conditions imposed at other life stages (e.g., juvenile migration through hydroelectric dams) is highly unlikely to prove effective,” according to Evaluating Tributary Restoration Potential for Pacific Salmon Recovery, Ecological Applications, 17(4), 2007

The majority of orca scientists agree with these findings. When the BiOp was being prepared in late 2007, prominent researchers urged NOAA to assure that endangered orcas were not further jeopardized by inadequate Chinook returning to the Columbia Basin. NOAA disregarded that plea and the BiOp included only a cursory salmon-orca analysis. In a conclusion based on little more than assertions, NOAA stated that the dam-related mortality inflicted on Chinook would not adversely affect Southern Residents. Subsequently, 14 leading researchers wrote NOAA Administrator Jane Lubchenco pointing out shortcomings in the BiOp and seeking reconsideration. Their letter concluded, “The recovery of Southern Resident Killer Whales depends on abundant food, which will be difficult, if not impossible, to provide without restoring productivity from the Columbia Basin.” Similar concerns were voiced by People for Puget Sound and Jean-Michel Cousteau. Again, NOAA ignored the scientists’ recommendations.

The decline of Snake River salmon populations matters not only to orcas. As they decline, the entire Snake River watershed, an area the size of France, is gradually deprived of essential marine nutrients and chemicals that have been transported upriver for thousands of years by migrating salmon leaving their spawned-out carcasses alongside rivers and streams throughout the wilderness. Pacific Salmon and Wildlife describes the crucial role salmon play in supporting overall ecosystem health. Bears, eagles, otters and beaver are among the 138 animal species that have evolved with salmon as an important part of their diet, and even trees contain chemicals brought upstream by salmon. Indeed, there are lakes once made fertile by returning salmon that now must be artificially fertilized with custom-mixed batches of nutrients to sustain the food web that thrived there before the Snake River dams were built.

In my next post, I’ll look at whether the Obama Administration has done anything to address the BiOp’s orca-related scientific deficiencies.

*(Howard Garrett began field studies of Southern Resident orcas in 1981 with the Center for Whale Research on San Juan Island. With his wife, Susan Berta, he is co-founder of Orca Network, based on Whidbey Island WA. Garrett is author of Orcas In Our Midst and a frequent speaker and writer about orca natural history and habitat protection.)

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