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Volume 2008/09, Issue 4
December 11, 2008 
In This Issue
2008/09 Calaveras River Juvenile Migration Monitoring
2008 Stanislaus River Weir Monitoring
Tributary Carcass Surveys
San Joaquin River Conditions
events
 
Dec. 11: TRTAC

links
U.S. Army Corps of Engineers California Reservoir Plots

Northwest Fisheries Science Center
Forecast of Adult Returns
for Coho in 2009 and
Chinook Salmon in 2010


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chinook carcass
Key Highlights
 
2008/09 Calaveras River Juvenile Migration Monitoring. A total of eight O. mykiss were captured during the reporting period, increasing the season total to 30.
 
2008 Stanislaus River Weir Monitoring. A total of 112 Chinook were recorded at the Stanislaus River weir between November 14 and November 30, increasing the season total to 863. In comparison, total passage through November 30 in previous years ranged from a low of 380 Chinook in 2007 to a high of 4,420 Chinook in 2003.

A total of four O. mykiss (one ad-clipped) were recorded passing upstream of the weir and zero recorded passing downstream of the weir, increasing the season total to 18 O. mykiss upstream and four O. mykiss downstream.
 
Tributary Carcass Surveys. Four more female Chinook were spawned at the Merced River Hatchery, increasing the season total to 10.
 
San Joaquin River Conditions. During the reporting period, flows in the San Joaquin River at Vernalis fluctuated between 1,016 cfs and 1,245 cfs.
 
Delta Exports. Combined total exports (state and federal pumps) exhibited a general decreasing trend during the reporting period ranging between 2,448 cfs and 6,590 cfs.

We encourage subscribers to contribute any relevant information for future issues of the newsletter (e.g., additional monitoring studies, announcements of upcoming meetings and events, etc). If you would like to contribute, please contact Chrissy Sonke.



 
2008/09 Calaveras River Juvenile Migration Monitoring
 
The Calaveras River rotary screw trap at Shelton Road (RM 28) sampled six days between November 14 and November 30.

A total of eight O. mykiss (Table 1) were captured during the reporting period, increasing the season total to 30. Daily catch ranged between zero and six O. mykiss (Figure 1). A total of one young-of-year (YOY; ≤100 mm) and seven Age 1+ (101-299 mm) O. mykiss were captured. Average forklengths and weights of O. mykiss are provided in Table 1. The O. mykiss captured and measured were rated as parr (n=3) and silvery parr (n=5).

No Chinook were captured during this reporting period.
 
Instantaneous temperatures taken at the trap ranged from 51F to 53F, and turbidity ranged from 0.8 NTU to 1.8 NTU. Daily average flow fluctuated between 24 cfs and 65 cfs at New Hogan Dam (NHG) and 0 cfs to 21 cfs at Bellota (MRS). No flow was recorded at Cosgrove (COS).

Table 1. Biosampling data for O. mykiss captured at Shelton Road between November 14 and November 30, 2008. Parentheses indicate range.
cal table 

cal catch
Figure 1. Daily O. mykiss catch at Shelton Road and Calaveras River flow recorded by combined New Hogan Dam and Cosgrove Creek (NHG+ COS), between November 14 and November 30, 2008.


2008 Stanislaus River Weir Monitoring

Between November 14 and November 30, a total of 112 Chinook were recorded passing upstream of the weir, increasing the season total to 873. In comparison, total passage through November 30 in previous years ranged from a low of 380 Chinook in 2007 to a high of 4,420 Chinook in 2003 (Figure 2). During this sampling period, daily upstream passage ranged between zero and 27 Chinook. Weir passage included five Chinook with clipped adipose fins (ad-clipped), increasing the season total of ad-clipped fish to 36 (4.1% of passage to date). Total length (estimated by the Vaki Riverwatcher) of Chinook passing upstream ranged from 430 mm to 1,030 mm  with 18.6% ranging between 750-759 mm (Figure 3). Grilse (<600 mm) accounted for 12% of the Chinook passing upstream of the weir which is similar to 2003, 2005, 2006, and 2007, but lower than 2004 (Figure 4).
 
cumulative count
Figure 2. Cumulative Chinook salmon upstream passage recorded at the Stanislaus River Weir, 2003 to 2008.
weir length
Figure 3. Length frequency of Chinook salmon recorded passing upstream of the Stanislaus River Weir, 2008.
 
grilse 

Figure 4. Percent Chinook salmon grilse (<600 mm) passing upstream of the Stanislaus River Weir between November 14 and November 30 for years 2004 to 2008.  "n" = total number of Chinook recorded during that time period.

Between November 14 and November 30, there were four O. mykiss (one ad-clipped) recorded passing upstream of the weir and zero recorded passing downstream of the weir, increasing the season total to 18 O. mykiss (nine ad-clipped) upstream and four O. mykiss (three ad-clipped) downstream. It is unknown whether passage detections of fish smaller than about 400 mm represent unique fish since it appears that some passage detections may be the same individual(s) passing up and downstream. Vaki-estimated total lengths for O. mykiss passing upstream without an adipose fin was 213 mm, and those with adipose fins ranged between 350 mm and 492 mm (Figure 5). Ad-clips indicate hatchery origin and ad-clipped O. mykiss are not released in the Stanislaus River. These fish may be from a September 23 release of 300 mm to 400 mm Mokelumne River Hatchery steelhead in San Pablo Bay. A small subset of the San Pablo Bay release group was acoustically tagged (i.e., 30) and nearly one-half (12 of 30) of these individuals have been acoustically detected upstream of their release location (i.e., at Chipps, Montezuma Slough, etc).
rbt length
Figure 5. Total length estimated and passage timing for O. mykiss passing upstream and downstream at the Stanislaus River Weir, 2008. "X" indicates absence of an adipose fin (i.e., ad-clipped).

One 24 hour trapping event was conducted during the sampling period (November 20-21). A total of three Chinook were trapped consisting of two males and one female. Total lengths ranged from 675 mm to 910 mm (avg: 828 mm). No O. mykiss were trapped during this period.

Releases from Goodwin Dam (GDW; RM 58.4) ranged between 246 cfs and 259 cfs and flow at Ripon (RIP; RM 15) ranged between 268 cfs and 290 cfs (Figure 6). Instantaneous water temperatures at the weir ranged between 51.8˚F and 55.2˚F, while daily average water temperatures at Ripon (RPN; RM 15) ranged between 53.2˚F and 57.2˚F (Figure 7). Instantaneous turbidity at the weir site ranged between 0.2 NTU and 1.0 NTU (Figure 8). Instantaneous dissolved oxygen at the weir ranged between 9.5 mg/L and 10.5 mg/L, while daily average dissolved oxygen at Ripon (RPN; RM 15) ranged between 9.7 mg/L and 10.3 mg/L (Figure 9).
flow and passage
Figure 6. Daily upstream Chinook passage recorded at the Stanislaus River Weir in relation to daily average flows (cfs) recorded in the Stanislaus River at Goodwin (GDW) and Ripon (RIP) and in the San Joaquin River at Vernalis (VNS), 2008. Note: flows downstream of Goodwin Dam may be higher than dam releases due to irrigation returns.
 
temp and passage
Figure 7. Daily upstream Chinook passage recorded at the Stanislaus River Weir in relation to instantaneous water temperature recorded at the weir and daily average water temperature recorded in the Stanislaus River at Ripon (RPN) and in the San Joaquin River at Vernalis (VER), Mossdale (MSD) and Rough & Ready (RRI), 2008.

turbidity and passage
Figure 8. Daily upstream Chinook passage recorded at the Stanislaus River Weir in relation to instantaneous turbidity recorded at the weir, 2008.
DO and passage
Figure 9. Daily upstream Chinook passage recorded at the Stanislaus River Weir in relation to instantaneous dissolved oxygen recorded at the weir and daily average dissolved oxygen recorded in the Stanislaus River at Ripon (RPN) and in the San Joaquin River at Mossdale (MSD) and Rough & Ready (RRI), 2008.



 

Tributary Carcass Surveys
 
The California Department of Fish and Game continued their annual adult fall-run Chinook carcass surveys throughout the reporting period on the Merced, Tuolumne, and Stanislaus Rivers.  As of November 17, seven weekly surveys have been completed. Although numbers are extremely low on all tributaries, the largest number of live fish was observed on the Stanislaus River with a peak live count thus far of 277 Chinook.  Peak live counts on the Tuolumne and Merced Rivers were 200 and 62, respectively.  Since spawning at the hatchery was initiated during week 5, an additional four females were spawned this period, increasing the season total to 10.

The largest number of redds was observed on the Stanislaus River with a peak redd count thus far of 226. Peak redd counts on the Tuolumne and Merced Rivers were 141 and 39, respectively. Typically, a peak in the number of redds observed occurs in mid-to-late November.

The total number of carcasses tagged through week seven on the Merced, Tuolumne, and Stanislaus rivers is 45, 67, and 86; respectively. The total number tagged carcass recoveries on the Merced, Tuolumne, and Stanislaus rivers were two, 12, and 13; respectively.

San Joaquin River Conditions 
 
During the reporting period, flows in the San Joaquin River at Vernalis fluctuated between 1,016 cfs and 1,245 cfs (Figure 10). Average daily water temperatures in the San Joaquin River ranged between 59.8F and 54.1F at Vernalis, between 61.0F and 51.4F at Mossdale; and between 60.9F and 58.0F at Rough 'n Ready Island (Figure 11). Average daily dissolved oxygen (DO) in the San Joaquin River ranged between 7.0 mg/L and 7.3 mg/L in the deep water ship channel (measured at Rough 'n Ready Island) and between 8.0 mg/L and 10.7 mg/L at Mossdale (Figure 12).
flow
Figure 10. San Joaquin River flow at Vernalis, 2007 to 2008.
temp
Figure 11. San Joaquin River daily average water temperature at Vernalis, Mossdale, and Rough 'n Ready, 2007 to 2008.
DO
Figure 12. San Joaquin daily average dissolved oxygen at Mossdale and Rough 'n Ready, 2007 to 2008.


Delta Exports

Mean daily pumping at the C.W. Jones Pumping Plant (federal pumps previously known as Tracy Pumping Plant) exhibited a general decreasing trend ranging between 1,020 cfs and 3,611 cfs (Figure 13). Mean daily pumping at the Harvey O. Banks Pumping Plant (state pumps) also exhibited a general decreasing trend ranging between 1,426 cfs and 2,983 cfs. Combined total exports (state and federal pumps) ranged between 2,448 cfs and 6,590 cfs.
 
exports
Figure 13. Daily exports at the C.W. Jones Pumping Plant (federal) and Harvey O. Banks Pumping Plant (state), 2007 to 2008.
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