Grande Ronde Endemic Spring Chinook Salmon Supplementation Project; Lostine River Operations and Maintenance 2007 Smolt Acclimation and Adult Return Report.

Abstract

The Nez Perce Tribe (NPT), through funding provided by the Bonneville Power Administration (BPA), has implemented a Chinook salmon supplementation program (250,000 smolts) on the Lostine River, a tributary to the Grande Ronde River of Oregon. The Grande Ronde Endemic Spring Chinook Salmon Supplementation project, which involves supplementation of the Upper Grande Ronde River and Catherine Creek in addition to the Lostine River, was established to prevent extirpation and increase the number of threatened Snake River spring/summer Chinook salmon (Oncorhynchus tshawytscha) returning to the Grande Ronde River. This report covers the eleventh season (1997-2007) of adult Chinook salmon broodstock collection in the Lostine River and the ninth season (1999-2007) of acclimation of resulting Lostine River progeny. Production of Lostine River spring Chinook salmon smolts currently occurs at Lookingglass Fish Hatchery (LGH). The Lostine River supplementation program utilizes two strategies to obtain egg source for production of smolts for supplementation: captive broodstock and conventional broodstock. The captive broodstock strategy involves (1) capture of natural juvenile spring Chinook salmon smolts from the Lostine River, (2) rearing those to adult and spawning them, and (3) rearing the resultant progeny for eventual acclimation and release back into the Lostine River. The conventional broodstock strategy involves (1) capture of natural and hatchery origin adults returning to the Lostine River, (2) holding those adults and spawning them, and (3) rearing the resultant progeny for acclimation and release back into the Lostine River. This report focuses on (1) the trapping and collection of adult spring Chinook salmon that return to the Lostine River, which provides the broodstock source for the conventional strategy and (2) the acclimation and release of juvenile spring Chinook salmon produced from the captive broodstock and conventional broodstock strategies In 2007, acclimation of Lostine River spring Chinook salmon smolts occurred from 3/5/07 through to 4/17/07 and a total of 230,010 smolts were acclimated and released. These smolts were produced from the brood year (BY) 2005 egg source and included captive brood (24,604) and conventional (205,406) origin smolts that were all progeny of Lostine River spring Chinook salmon. Operation of the Lostine River adult monitoring and collection facility in 2007 began May 14th. The first Chinook was captured on June 2, 2007 and the last Chinook was captured on September 25, 2007. The weir and trap were removed on October 1, 2007. A total of 637 adult Chinook, including jacks, were captured during the season. The composition of the run included 240 natural origin fish and 397 hatchery supplementation fish. There were no identified 'stray' hatchery fish from other programs trapped. Of the fish captured, 41 natural and 81 hatchery supplementation adults were retained for broodstock and transported to LGH for holding and spawning, 403 adult Chinook were passed or transported above the weir to spawn naturally, and only hatchery origin jack Chinook were transported and outplanted in the Wallowa River and Bear Creek in underseeded habitat. Of the 122 adult fish retained for broodstock, 20 natural females and 40 supplementation females were represented in spawning. The eggs from these females produced a total of 267,350 eggs at fertilization. Eye-up was 86.73% which yielded a total of 231,882 conventional program eyed eggs. The fecundity averaged 4,456 eggs per female. These eggs will be incubated and reared at Lookingglass Hatchery until they are smolts in the spring of 2009. Captive brood program eggs/fish will be added to the conventional program eggs to make up the entire juvenile release for the Lostine River program in 2009. Due to the success of the 2007 egg collection, the number of fish produced exceeded program needs and facility capabilities. As a result, there are plans to outplant fry in 2008 and parr in early 2009 to underseeded habitat in the Wallowa River.