scholarly journals Impact of Redd Loss at Vernita Bar on Hanford Reach Chinook Salmon Production: Final Report 1988.

1988 ◽  
Author(s):  
Donald E Rogers
Keyword(s):  
Chinook Salmon ◽  
Final Report ◽  
Salmon Production ◽  
Hanford Reach

Challenges for Diadromous Fishes in a Dynamic Global Environment

2009 ◽  
Keyword(s):  
Chinook Salmon ◽  
Large Scale ◽  
Coho Salmon ◽  
Pacific Salmon ◽  
Pink Salmon ◽  
Commercial Catch ◽  
Atmospheric Processes ◽  
Energy Transfers ◽  
Salmon Production ◽  
The Impact

<em>Abstract</em>.-Pacific salmon <em>Oncorhynchus </em>spp. catches are at historic high levels. It is significant that one of the world's major fisheries for a group of species that dominates the surface waters of the subarctic Pacific is actually very healthy. Natural trends in climate are now recognized to cause large fluctuations in Pacific salmon production, as shown in historical records of catch and recent changes probably have been affected by greenhouse gas induced climate changes. Pink salmon <em>O. gorbuscha </em>and chum salmon <em>O. keta </em>production and catch has increased in the past 30 years and may continue in a similar trend for for the next few decades. Coho salmon <em>O. kisutch </em>and Chinook salmon <em>O. tshawytscha </em>catches have been declining for several decades, particularly at the southern end of their range, and they may continue to decline. In the 1970s, hatcheries were considered to be a method of adding to the wild production of coho and Chinook salmon because the ocean capacity to produce these species was assumed to be underutilized. Large-scale changes in Pacific salmon abundances are linked to changes in large-scale atmospheric processes. These large-scale atmospheric processes are also linked to planetary energy transfers, and there is a decadal scale pattern to these relationships. Pacific salmon production in general is higher in decades of intense Aleutian lows than in periods of weak Aleutian lows. Key to understanding the impact of climate change on Pacific salmon is understanding how the Aleutian low will change. Chinook and coho salmon are minor species in the total commercial catch, but important socially and economically in North America. A wise use of hatcheries may be needed to maintain abundances of these species in future decades.

Suitability criteria analyzed at the spatial scale of redd clusters improved estimates of fall chinook salmon (Oncorhynchus tshawytscha) spawning habitat use in the Hanford Reach, Columbia River

2000 ◽  
Vol 57 (8) ◽  
pp. 1636-1646 ◽  
Author(s):  
David R Geist ◽  
Julia Jones ◽  
Christopher J Murray ◽  
Dennis D Dauble
Keyword(s):  
Habitat Use ◽  
Spatial Scale ◽  
Chinook Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Columbia River ◽  
Water Velocity ◽  
Point Pattern ◽  
Spawning Habitat ◽  
Cluster Location ◽  
Hanford Reach

We improved our predictions of fall chinook salmon (Oncorhynchus tshawytscha) habitat use by analyzing spawning habitat at the spatial scale of redd clusters. Spatial point pattern analyses indicated that redd clusters in the Hanford Reach, Columbia River, were consistent in their location from 1994 to 1995. Redd densities were 16.1 and 8.9 redds·ha-1 in 1994 and 1995, respectively, and individual redds within clusters were usually less than 30 m apart. Pattern analysis also showed strong evidence that redds were uniformly distributed within the clusters where interredd distances ranged from 2 to 5 m. Redd clusters were found to occur predominantly where water velocity was between 1.4 and 2 m·s-1, water depth was 2-4 m, and lateral slope of the riverbed was less than 4%. This habitat use represented a narrower range of use than previously reported for adult fall chinook salmon. Logistic regression analysis determined that water velocity and lateral slope were the most significant predictors of redd cluster location over a range of river discharges. Overestimates of available spawning habitat lead to nonachievable goals for protecting and restoring critical salmonid habitat. Better predictions of spawning habitat may be possible if cluster-specific characteristics are used.

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