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Title: Re-Introduction of Lower Columbia River Chum Salmon into Duncan Creek, 2001-2002 Annual Report.

The National Marine Fisheries Service (NMFS) listed Lower Columbia River chum as threatened under the auspices of the Endangered Species Act (ESA) in March of 1999 (64 FR 14508, March 25, 1999). The listing was in response to reduction in abundance from historical levels of more than half a million returning adults to fewer than 10,000 spawners present day (Johnson et al. 1997). Harvest, loss of habitat, changes in flow regimes, riverbed movement and heavy siltation have been largely responsible for the decline in this species in the Columbia River. The timing of seasonal changes in river flow and water temperatures is perhaps the most critical factor in structuring the freshwater life history of chum salmon (Johnson et al. 1997). This is especially true of the population located directly below Bonneville Dam where hydropower operations can block access to spawning sites, dewater redds, strand fry, cause scour or fill of redds and increase sedimentation of spawning gravels. The recovery strategy for Lower Columbia River chum as outlined in the Hatchery Genetic Management Plan (HGMP) for the Grays River project has four main tasks. First, determine if remnant populations of Lower Columbia River chum salmon exist in Lower Columbia River tributaries.more » Second, if such populations exist, develop stock-specific recovery plans that would involve habitat restoration including the creation of spawning refugias, supplementation if necessary and a habitat and fish monitoring and evaluation plan. If chum have been extirpated from previously utilized streams, develop re-introduction plans that utilize appropriate genetic donor stock(s) of Lower Columbia River chum salmon and integrate habitat improvement and fry-to-adult survival evaluations. Third, reduce the extinction risk to Grays River chum salmon population by randomly capturing adults in the basin for use in a supplementation program and reintroduction of Lower Columbia River chum salmon into the Chinook River basin. The Duncan Creek project has two goals: (1) re-introduction of chum into Duncan Creek by providing off channel high quality spawning and incubation areas and (2) to simultaneously evaluate natural re-colonization and a supplementation strategy where adults are collected and spawned artificially at a hatchery. The eggs from these artificial crossings are then either incubated at Duncan Creek or incubated and the fry reared at the hatchery to be released back into Duncan Creek. Tasks associated with the first goal include: (1) removing mud, sand and organics present in four of the creek branches and replace with gravels expected to provide maximum egg-to-fry survival rates to a depth of at least two feet; (2) armoring the sides of these channels to reduce importation of sediment by fish spawning on the margins; (3) planting native vegetation adjacent to these channels to stabilize the banks, trap silt and provide shade; (4) annual sampling of gravel in the spawning channels to detect changes in gravel composition and sedimentation levels.« less
Authors:
 [1]
  1. (Washington Department of Wildlife, Olympia, WA)
Publication Date:
OSTI Identifier:
807635
Report Number(s):
DOE/BP-00007373-1
R&D Project: 200105300; TRN: US200305%%1049
DOE Contract Number:
00007373
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: 1 Jan 2003
Research Org:
Washington Department of Wildlife
Sponsoring Org:
United States. Bonneville Power Administration.
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; 59 BASIC BIOLOGICAL SCIENCES; COLUMBIA RIVER; ENDANGERED SPECIES; EVALUATION; FISHERIES; GENETICS; HABITAT; MONITORING; PLANTS; RIVERS; SALMON; SEDIMENTATION Chum salmon - Spawning - Columbia River - Statistics