skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Spring Chinook Salmon Interactions Indices and Residual/Precocious Male Monitoring in the Upper Yakima Basin; Yakima/Klickitat Fisheries Project Monitoring and Evaluation, 2004-2005 Annual Report.

Technical Report ·
DOI:https://doi.org/10.2172/887232· OSTI ID:887232
;  [1];  [2]
  1. Washington Department of Fish and Wildlife, Olympia, WA
  2. Cascade Aquatics, Ellensburg, WA

This report examines some of the factors that can influence the success of supplementation, which is currently being tested in the Yakima Basin using upper Yakima stock of spring chinook salmon. Supplementation success in the Yakima Basin is defined relative to four topic areas: natural production, genetics, ecological interactions, and harvest (Busack et al. 1997). The success of spring chinook salmon supplementation in the Yakima Basin is dependent, in part, upon fish culture practices and favorable physical and biological conditions in the natural environment (Busack et al. 1997; James et al. 1999; Pearsons et al., 2003; Pearsons et al. 2004). Shortfalls in either of these two topics (i.e., failure in culturing many fish that have high long-term fitness or environmental conditions that constrain spring chinook salmon production) will cause supplementation success to be limited. For example, inadvertent selection or propagation of spring chinook that residualize or precocially mature may hinder supplementation success. Spring chinook salmon that residualize (do not migrate during the normal migration period) may have lower survival rates than migrants and, additionally, may interact with wild fish and cause unacceptable impacts to non-target taxa. Large numbers of precocials (nonanadromous spawners) may increase competition for females and significantly skew ratios of offspring sired by nonanadromous males, which could result in more nonanadromous spring chinook in future generations. Conditions in the natural environment may also limit the success of spring chinook supplementation. For example, intra or interspecific competition may constrain spring chinook salmon production. Spring chinook salmon juveniles may compete with each other for food or space or compete with other species that have similar ecological requirements. Monitoring of spring chinook salmon residuals, precocials, prey abundance, carrying capacity, and competition will help researchers interpret why supplementation is working or not working (Busack et al. 1997). Monitoring ecological interactions will be accomplished using interactions indices. Interactions indices will be used to index the availability of prey and competition for food and space. The tasks described below represent various subject areas of juvenile spring chinook salmon monitoring but are treated together because they can be accomplished using similar methods and are therefore more cost efficient than if treated separately. Topics of investigation we pursued in this work were: (1) strong interactor monitoring (competition index and prey index), (2) carrying capacity monitoring (microhabitat monitoring); (3) residual and precocious male salmon monitoring (abundance); (4) performance of growth modulation in reducing precocious males during spawning; (5) incidence of predation by residualized chinook salmon; and (6) benefits of salmon carcasses to juvenile salmonids. This report is organized into six chapters to represent these topics of investigation. Data were collected during the summer and fall, 2004 in index sections of the upper Yakima Basin (Figure 1). Previous results on the topics in this report were reported in James et al. (1999), and Pearsons et al. (2003; 2004). Hatchery-reared spring chinook salmon were first released during the spring of 1999. The monitoring plan for the Yakima/Klickitat Fisheries Project calls for the continued monitoring of the variables covered in this report. All findings in this report should be considered preliminary and subject to further revision as more data and analytical results become available.

Research Organization:
Bonneville Power Administration (BPA), Portland, OR (United States)
Sponsoring Organization:
USDOE
DOE Contract Number:
00017478
OSTI ID:
887232
Report Number(s):
DOE/BP-00017478-5; R&D Project: 199506325; TRN: US200617%%615
Country of Publication:
United States
Language:
English