USFWS reviews sturgeon, bull trout recovery efforts

October 28, 2017

Since white sturgeon in Montana’s Kootenai River was listed as endangered in 1994, the U.S. Fish and Wildlife Service has completed several iterations of biological opinions and critical habitat designations for the freshwater fish. Along the way, bull trout were listed in 1999, three Biological Opinions (BiOps) were approved, two lawsuits challenged the Service’s BiOp results, finally resulting in the 2006 BiOp for sturgeon and bull trout that was effective through 2016 and has been extended through 2018. And, finally, the Service is in the process of preparing a 2018 BiOp. The sturgeon’s decline was largely due to the construction of Libby Dam and the changes in river flows caused by the dam’s operations. Other factors – flood plain development, contaminant runoff, over harvest and agricultural activities – also contributed to the sturgeon’s decline. Libby Dam, built in 1974 and operated by the U.S. Army Corps of Engineers, is a major storage dam on the Kootenai. Lake Koocanusa backs up 90 miles behind the dam, with 42 of those miles in British Columbia. The Service completed its first BiOp in 1995 on the federal Columbia River power system’s effects on the sturgeon, as well as four species of snails. Complicating the results of that BiOp was the listing of bull trout in 1999 as threatened under the federal Endangered Species Act, causing a reinitiation of ESA consultation of the 1995 BiOp to address bull trout. The Service completed a second BiOp in 2000, but the Center for Biological Diversity sued the agency in 2003, challenging both the BiOp and designated critical habitat associated with the sturgeon. The Service issued a new BiOp in February 2006, finding that the proposed operations of Libby Dam caused jeopardy for white sturgeon, but reached a no-jeopardy opinion on bull trout, according to the Service’s Jason Flory, speaking at the Northwest Power and Conservation Council’s October meeting in Columbia Falls, Montana. The reasonable and prudent alternative of the 2000 BiOp focused on flow management, Flory said, calling on operations at the dam to provide peak natural spring flows that would encourage sturgeon to move upstream into spawning area for 42 consecutive days each year. The peak flows required by the BiOp, however, were not very specific regarding timing. It just said spring flows, Flory said. The RPA in the 2006 BiOp expanded the options towards recovery and provided a “suite of performance-based alternatives designed to achieve habitat changes that would assist the sturgeon with spawning and rearing below Libby Dam,” an October 3 Council memo introducing the Libby BiOp update said. A follow-up challenge of the Service’s critical habitat designation by the Center for Biological Diversity in 2007 asked for a re-consultation and for the federal agency to finalize its critical habitat designation. That suit resulted in a 2008 settlement between the plaintiffs, the CBD, the Kootenai Tribe of Idaho and the State of Montana, and the defendants, the Service, the Corps and the Bonneville Power Administration. With the settlement, U.S. District Court Judge Donald Molloy dismissed the case September 11, 2008. Once the 2006 BiOp and settlement were concluded, the full suite of performance alternatives focused on in-river attributes, Flory said. They included a renewed focus on specific flow management, three years of spill tests, adding two turbines to Libby Dam, improvements to the dam’s temperature control system, VARQ flood management, habitat improvements downstream of the dam by the Kootenai Tribe of Idaho and, for sturgeon, a conservation aquaculture program to artificially add sturgeon to the river. The spill tests, Flory said, did not result in a change in sturgeon behavior (although spill has occurred during high water), so operations the last few years have focused on timing of releases and temperature of the water during the spring. “The intent is to coax sturgeon to migrate further upstream and to create better habitat with deeper pools when they get there,” Flory said. He added that preliminary data is showing that about 20 percent more sturgeon are migrating upstream of Bonner’s Ferry into those spawning areas. Variable flow, or VARQ (Q refers to flow), flood control has been in effect at Libby Dam since 2003. In 2009, the Corps signed a Record of Decision for the flood control plan. Prior to the ROD, the dam would generally release high flows from January through April in order to make space to capture the spring runoff in May, June, and July. Because of the large amount of water drafted, historically little water was released from May through July period to allow refill of the reservoir. During the draft season in a majority of years VARQ provides less flood storage space than standard flood control in Libby's reservoir, Lake Koocanusa. During the spring-early summer refill, water releases from the dam will vary based on the year's April-August water supply forecast for the basin. The water release adjustments compensate for the reduced winter reservoir draft under VARQ. VARQ also helps by stabilizing flows downriver in all but the highest water years by sending more water downstream in spring and early summer. In 2010, the Service finalized critical habitat designation for bull trout. The Service is again in the process of reinitiating ESA consultation for both species the next iteration of the Kootenai River BiOp. The agency has extended the 2006 Libby BiOp beyond 2016 and through 2018. The current schedule, according to Flory, is to have a final biological assessment from the action agencies this month and for the Service to complete the BiOp December 31, 2018.