Relationship between chinook salmon (Oncorhynchus tshawytscha) redd densities and PHABSIM-predicted habitat in the Merced and Lower American rivers, California

1999 ◽  
Vol 56 (4) ◽  
pp. 570-577 ◽  
Author(s):  
Sean P Gallagher ◽  
Mark F Gard

An index of chinook salmon (Oncorhynchus tshawytscha) spawning habitat predicted using the physical habitat simulation system (PHABSIM) component of the instream flow incremental methodology was compared with redd densities and locations for sites in the Merced River, California, during 1996 and with redd numbers in sites in the Merced and Lower American rivers, California, from 1989 through 1996. Predicted weighted useable area (WUA) was significantly correlated with chinook salmon spawning density and location at five of seven sites in the Merced River. At the microhabitat level, in the Merced River during 1996, there was a significant relationship between chinook salmon redd location and predicted WUA. Cells with more WUA in the Merced River tended to have more redds. At the mesohabitat level, there was a significant relationship between redd density and predicted WUA in both rivers. Transect areas in the Merced River with higher predicted WUA had more redds. Sites with higher numbers of redds had more predicted WUA. Significant correlations between predicted WUA and spawning locations increase confidence in the use of PHABSIM modeling results for fisheries management in the Merced and Lower American rivers as well as in other rivers.

2000 ◽  
Vol 57 (8) ◽  
pp. 1636-1646 ◽  
Author(s):  
David R Geist ◽  
Julia Jones ◽  
Christopher J Murray ◽  
Dennis D Dauble

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.


2016 ◽  
Vol 73 (7) ◽  
pp. 1047-1059 ◽  
Author(s):  
Philip Roni ◽  
Christopher Johnson ◽  
Trenton De Boer ◽  
George Pess ◽  
Andrew Dittman ◽  
...  

Mortality during incubation is believed to be a major factor limiting the recovery of many salmon populations, though direct field measurements of egg-to-fry survival are rare or small in scale. To determine the effects of physical habitat (river reach, fine sediment intrusion, scour), parentage (mating, source of gametes) on Chinook salmon (Oncorhynchus tshawytscha) egg-to-fry survival and developmental stage at emergence across a basin, we constructed 324 artificial redds in nine reaches over 4 years in the Yakima River Basin, Washington, USA. Mean egg-to-fry survival ranged from 49% to 69% annually from 2009 to 2012 brood years. Survival was significantly different among reaches in 2010, but not in 2009, 2011, or 2012, while mating was a significant factor in all years but 2010. In contrast, developmental stage differed significantly among reaches and matings in all 4 years. Percentage of fines, days-in-gravel, and median particle size explained only small (<10%) additional amount of variation in survival or developmental stages. Our results suggest that parentage and reach within a basin are major factors influencing egg-to-fry survival, but their relative influence varies annually, presumably depending on the magnitude of high flows and scour during incubation.


2004 ◽  
Vol 61 (1) ◽  
pp. 23-33 ◽  
Author(s):  
Timothy P Hanrahan ◽  
Dennis D Dauble ◽  
David R Geist

Chief Joseph Dam on the Columbia River is the upstream terminus for anadromous fish because of its lack of fish passage facilities. Management agencies are currently evaluating the feasibility of reintroducing anadromous fish upriver of Chief Joseph Dam. We evaluated the physical characteristics of potential fall chinook salmon (Oncorhynchus tshawytscha) spawning habitat in the upper section of Chief Joseph Reservoir. The objectives were to estimate the location and quantity of potential spawning habitat and to determine the redd capacity of the area based on spawning habitat characteristics. The suitability of the study area was estimated through the use of geomorphic analysis, empirical physical data, and modeled hydraulic data. We estimated that 5% (48.7 ha) of the study area contains potentially suitable fall chinook salmon spawning habitat. Potential spawning habitat is primarily limited by deep water and low water velocities, resulting in 20% (9.6 ha) of the potential spawning habitat being characterized as high quality. Estimates of redd capacity within potential spawning habitat range from 207 to 1599 redds. The results of our study provide fisheries managers with useful information for evaluating the complex issue of reintroducing anadromous fish to the Columbia River upstream of Chief Joseph Dam.


2011 ◽  
Vol 29 (3) ◽  
pp. 297-312 ◽  
Author(s):  
D. Shallin Busch ◽  
Mindi Sheer ◽  
Kelly Burnett ◽  
Paul McElhany ◽  
Tom Cooney

Sign in / Sign up

Export Citation Format

Share Document