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Volume 2009/10, Issue 1
October 21, 2009
In This Issue
2009 Stanislaus River Weir Monitoring
2009 Tuolumne River Weir Monitoring
2009 San Joaquin Basin Escapement Surveys
Fall-run Chinook Salmon Predictions
San Joaquin Conditions
Delta Exports
events
 
Oct 22: VAMP Biology Technical Team Meeting

Nov 1-5: CERF Biennial conference

Nov 7: Stanislaus River Salmon Festival

Dec 10: TRTAC Meeting

links

FISHBIO

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field notes
Weir aerial
  Aerial photo of the Tuolumne River weir by FISHBIO.
 
Key Highlights
 
2009 Stanislaus River Weir Monitoring began immediately after installation was completed on September 9, 2009. A total of 256 Chinook salmon were detected as they passed upstream of the weir between September 9 and October 11.

2009 Tuolumne River Weir Monitoring began immediately after installation was completed on September 22, 2009. A total of five Chinook salmon were detected as they passed upstream of the weir between September 22 and October 11.
 
2009 San Joaquin Basin Escapement Surveys. Annual carcass surveys conducted by CDFG began in each tributary during the week of October 5.

Fall-run Chinook Salmon Predictions. A biologist with the U.S. Fish and Wildlife Service at Coleman National Fish Hatchery, Kurt Brown, says there appears to be more jack salmon in the Sacramento River (immature, 2-year old males that follow adults upstream), which is used to predict the next year's return.

San Joaquin River Conditions. San Joaquin River flow at Vernalis was initially relatively stable between 513 cfs and 716 cfs, before it began increasing on September 14 to a high of 1,135 cfs on October 11. Water temperatures in the San Joaquin River exhibited an overall decreasing trend ranging between 78.9F and 61.8F. Average daily dissolved oxygen (DO) in the San Joaquin River increased from 5.4 mg/L to 8.4 mg/L at Rough 'n Ready and fluctuated between 7.6 mg/L and 13.4 mg/L at Mossdale.
 
Delta Exports. Combined total exports (state and federal pumps) steadily decreased during the reporting period from 8,597 cfs to 4,132 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.
 

 
2009 Stanislaus River Weir Monitoring 
 
The Stanislaus River Weir was installed in the same location as past years, i.e., approximately two river miles downstream of Jacob Meyers Park (RM 31.4) near the town of Riverbank (Figure 1 and 2). Monitoring began immediately after installation was completed on September 9 and is expected to continue through the fall-run Chinook salmon migration season. This is the seventh consecutive year that fall-run Chinook salmon and steelhead migration in the Stanislaus River will be monitored using an Alaskan weir and Vaki Riverwatcher (Vaki) fish counter (Figure 3).
 
 
Stanislaus weir installationStanislaus weir

A total of 256 Chinook were detected as they passed upstream of the weir between September 9 and October 11 (Figure 3). Daily passage ranged between zero and 53 Chinook. Passage for the month of September already accounts for 63% of the low 2007 season total which was 408 Chinook. The number observed so far this year is similar to numbers observed during the same period in 2004 through 2006 and 2008 (Table 1).

Vaki photos
  
Figure 3. Photographs taken by the Vaki Riverwatcher as Chinook pass upstream through the Stanislaus River Weir.


Table 1. Annual Fall-run Chinook passage prior to October 12, 2003-2009.
weir numbers

Instantaneous water temperatures measured at the weir ranged between 55.9˚F and 64.9˚F (Figure 4), instantaneous turbidity ranged between 0.1 NTU and 4.0 NTU (Figure 5), and instantaneous dissolved oxygen ranged between 7.0 mg/L and 10.3 mg/L (Figure 6). Daily average water temperatures at Ripon (RPN; RM 15) ranged between 58.5˚F and 73.1˚F and dissolved oxygen ranged between 7.8 mg/L and 10.8 mg/L (Figure 6).

Daily average flow in the Stanislaus River at Goodwin Dam (GDW; RM 58) increased from 200 cfs to 700 cfs, three days after monitoring began. Flows remained at 700 cfs through September 30 and then were ramped down to a base flow of 200 cfs. Flows at Ripon (RIP, RM 15) fluctuated between 214 cfs and 604 cfs (Figure 7). Note: flows downstream of Goodwin Dam may be higher than dam releases due to irrigation returns and other factors.


Weir temperature and passage

Figure 4. 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), 2009.

turbidity and passage

Figure 5. Daily upstream Chinook passage recorded at the Stanislaus River Weir in relation to instantaneous turbidity recorded at the weir, 2009.

weir DO and passage
 
Figure 6. 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), 2009.

weir flow and passage
 
Figure 7. 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), 2009.


 
2009 Tuolumne River Weir Monitoring
 
The Tuolumne River Weir was fabricated in August and installed approximately two river miles downstream of Fox Grove Fishing Access (RM 24) near the town of Hughson.(Figure 8 and 9). Monitoring began immediately after installation was completed on September 22 and is expected to continue through the fall-run Chinook salmon migration season. This is the first year that fall-run Chinook salmon and steelhead migration will be monitored using an Alaskan weir and Vaki Riverwatcher (Vaki) fish counter. This Vaki Riverwatcher is a newer system than that used at the Stanislaus River Weir and captures video clips rather than photos to assist in the verification of identifying the species of fish passing the weir (Figure 10).          
 Tuolumne fabricationTuolumne Weir 
A total of five Chinook were detected as they passed
upstream of the weir between September 22 and October 11 (Figure 10). Daily passage ranged between zero and two Chinook.

screen grab

Figure 10. Vaki Riverwatcher video clip of a Chinook salmon passing upstream through the Tuolumne River Weir. Click on the photo to view the video.

Instantaneous water temperatures measured at the weir ranged between 60.0˚F and 79.3˚F (Figure 11), instantaneous turbidity ranged between 0.2 NTU and 4.6 NTU (Figure 12), and instantaneous dissolved oxygen ranged between 7.1 mg/L and 9.5 mg/L (Figure 13). Daily average water temperatures at Modesto (MOD; RM 17) ranged between 58.5˚F and 73.1˚F.

Daily average flow in the Tuolumne River fluctuated between 102 cfs and 292 cfs at La Grange (LGN; RM 50) and fluctuated between 174 cfs and 269 cfs at Modesto (MOD; RM 17) (Figure 14). Note: flows downstream of La Grange may be higher than dam releases due to accretion and Dry Creek inflow.

Weir temperature and passage

Figure 11. Daily upstream Chinook passage recorded at the Tuolumne River Weir in relation to instantaneous water temperature recorded at the weir and daily average water temperature recorded in the Tuolumne River at Modesto (MOD) and in the San Joaquin River at Vernalis (VER), Mossdale (MSD) and Rough & Ready (RRI), 2009.

weir turbidity and passage
 
Figure 12. Daily upstream Chinook passage recorded at the Tuolumne River Weir in relation to instantaneous turbidity recorded at the weir, 2009.
 
weir DO and passage

Figure 13. Daily upstream Chinook passage recorded at the Tuolumne River Weir in relation to instantaneous dissolved oxygen recorded at the weir and daily average dissolved oxygen recorded in the San Joaquin River at Mossdale (MSD) and Rough & Ready (RRI), 2009.

weir flow and passage
 
Figure 14. Daily upstream Chinook passage recorded at the Tuolumne River Weir in relation to daily average flows (cfs) recorded in the Tuolumne River at La Grange (LGN) and Modesto (MOD) and in the San Joaquin River at Vernalis (VNS), 2009.



 
2009 San Joaquin Basin Escapement Surveys 
 
Annual carcass surveys conducted by CDFG began in each tributary during the week of October 5. 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 seven Chinook. Peak live counts on the Tuolumne and Merced Rivers were six and three, respectively.

The highest number of redds was observed on the Stanislaus River with a peak redd count thus far of 6 and zero redds have been recorded on the Tuolumne and Merced Rivers. Typically, a peak in the number of redds observed for the fall-run season occurs in mid to late November.

Zero females have been spawned at the Merced River Fish Facility (MRFF).

 
Fall-run Chinook Salmon Predictions
 
Fall-run salmon are beginning to return to the Sacramento and San Joaquin River systems.  However, it is too early to tell if returns will be significantly greater this year compared to the past couple of years when escapement was at a record low since the drought that occurred from 1988 to 1992.  A biologist with the U.S. Fish and Wildlife Service at Coleman National Fish Hatchery, Kurt Brown, says there appears to be more jack salmon in the Sacramento River (immature, 2-year old males that follow adults upstream), which is used to predict the next year's return.  A large number of jacks equates to a more productive return the following year. The Columbia River has seen four times the 10-year average number of jacks, which could mean a huge return to the Columbia River in 2010.

It is believed that poor ocean conditions contributed, at least in part, to the decline in the number of salmon returning to the Sacramento-San Joaquin Basin during the past few years.  This year conditions appear to have improved with cooler water temperatures, more upwelling and an increase in food supply (e.g. krill).  Forecasters are predicting that 122,000 salmon will make it back to the Sacramento River system (view entire articles: http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2009/10/08/SPD91A2IKA.DTL; http://www.cbbulletin.com/356408.aspx).


 
San Joaquin Conditions
 
During the reporting period, flows in the San Joaquin River at Vernalis were initially relatively stable between 513 cfs and 716 cfs, and then began increasing on September 14 to approximately 1,000 cfs through October 11 (Figure 15). Water temperatures in the San Joaquin River exhibited an overall decreasing trend ranging from 78.0F to 61.8F at Vernalis; from 78.8F to 62.2F at Mossdale; and from 78.9F to 66.0F at Rough 'n Ready Island (Figure 16). Average daily dissolved oxygen (DO) in the San Joaquin River increased from 5.4 mg/L to 8.4 mg/L in the deep water ship channel (measured at Rough 'n Ready Island) and fluctuated between 7.6 mg/L and 13.4 mg/L at Mossdale (Figure 17).

 
 SJR flow


Figure 15. San Joaquin River flow at Vernalis, August 1, 2008 through October 11, 2009.

 

SJR temperature 

 
Figure 16. San Joaquin River daily average water temperature at Vernalis, Mossdale, and Rough 'n Ready, August 1, 2008 through October 11, 2009.
 

SJR Dissolved oxygen 
 
Figure 17. San Joaquin daily average dissolved oxygen at Mossdale and Rough 'n Ready, August 1, 2008 through October 11, 2009.

 
Delta Exports 
 
Mean daily pumping at the C.W. Jones Pumping Plant (federal pumps previously known as Tracy Pumping Plant) decreased during the reporting period from 4,285 cfs to 3,771 cfs (Figure 18). Mean daily pumping at the Harvey O. Banks Pumping Plant (state pumps) decreased during the reporting period from 4,464 cfs to 272 cfs. Combined total exports (state and federal pumps) decreased during the reporting from 8,597 cfs to 4,132 cfs.
 

Exports 

Figure 18. Daily exports at the C.W. Jones Pumping Plant (federal) and Harvey O. Banks Pumping Plant (state), August 1, 2008 through October 11, 2009.

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