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Volume 2010/11, Issue 6
December 22, 2010
In This Issue
Calaveras River Juvenile Migration Monitoring
Tuolumne River Juvenile Migration Monitoring
Stanislaus River Weir Monitoring
Tuolumne River Weir Monitoring
Merced River Conditions
San Joaquin Basin Escapement Surveys
Mokelumne River Woodbridge Dam Fish Ladder Monitoring
San Joaquin Conditions
Delta Exports
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Salmon Escapement Project Work Team Meeting:
Jan. 18

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FISHBIO



Trout Unlimited California

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field notes
Sac-Fry Chinook salmon
  Photo by FISHBIO.
Key Highlights


Calaveras River Juvenile Migration Monitoring at Shelton Road (RM 28) continued sampling during the reporting period, and a total of 165 O. mykiss were captured.

Tuolumne River Juvenile Migration Monitoring at Waterford (RM 30) began on December 3 and a total of 17 Chinook salmon fry were captured through December 12.

Stanislaus River Weir Monitoring continued during the reporting period and 1,346 Chinook salmon have been counted as of December 12.

Tuolumne River Weir Monitoring was suspended due to high flows and a total of 766 Chinook salmon were counted through November 30.

Merced River. As of December 10, forty-two Chinook salmon have been spawned at the Merced River Fish Facility

San Joaquin Basin Escapement Surveys. Annual carcass surveys conducted by California Department of Fish and Game (CDFG) continued during the week of December 6. Observations of live adult Chinook salmon and spawning activity (redds) have been on the decline since mid-November.

Mokelumne River Woodbridge Dam Fish Ladder Monitoring. As of December 12, a total of 7,052 Chinook passed upstream of the dam.


San Joaquin River Conditions. San Joaquin River flows at Vernalis ranged between 1,761 cfs and 5,288 cfs. Water temperatures in the San Joaquin River ranged between 47.1F and 57.5F. Average daily dissolved oxygen (DO) in the San Joaquin River fluctuated between 8.9 mg/L and 10.9 mg/L at Mossdale, and between 8.0 mg/L and 9.1 mg/L at Rough 'n Ready.

Delta Exports.Combined total exports (state and federal pumps) fluctuated during the reporting period and ranged from 8,551 cfs to 10,508 cfs.


 
2010/11 Calaveras River Juvenile Migration Monitoring
O. mykiss
Figure 1. O. mykiss captured at the Calaveras River rotary screw trap.


The Calaveras River rotary screw trap at Shelton Road (RM 28) was operated twelve days between November 22 and December 12. A total of 165 O. mykiss were captured during the reporting period, with daily catches ranging between 2 and 93 individuals (Figure 1). Of the O. mykiss captured, 122 were measured, and all were Age 1+ (100-299 mm) rated as parr (n=7), silvery parr (n=67), and smolt (n=47). Average forklengths and weights of O. mykiss are provided in Table 1.


No Chinook salmon were captured during this reporting period.


Instantaneous temperature recorded at the trap ranged from 43.8F to 54.6F, and turbidity ranged from 0.48 NTU to 2.23 NTU. Daily average flow fluctuated between 21 cfs and 50 cfs at New Hogan Dam (NHG), 0 cfs to 38 cfs at Bellota (MRS), and 1 cfs to 30 cfs at Cosgrove Creek (COS; Figure 2).


Table 1. Biosampling data for O. mykiss captured at Shelton Road between November 22 and December 12, 2010. Parentheses indicate range.

Catch Table

 

 Flow and Catch

Figure 2. Daily O. mykiss catch at Shelton Road, and Calaveras River flow recorded by New Hogan Dam (NHG) and Cosgrove Creek (COS) combined, and flow recorded at Bellota (MRS), between November 1 and December 12, 2010.

 

 
2010/11 Tuolumne River Juvenile Migration Monitoring

The Tuolumne River rotary screw trap at Waterford (RM 30) was installed December 1 and monitoring began on December 3 to sample during increased flows due to flood control. The trap sampled continuously between December 3 and December 12.

Chinook salmon fry
Figure 3. Chinook salmon fry captured at Tuolumne River rotary screw trap in Waterford.


A total of 17 juvenile Chinook salmon fry were captured during the reporting period. Daily catch ranged between zero and five Chinook (Figure 3). Average forklengths and weights of all the Chinook salmon are provided in Table 2. Most of the fry were buttoned up, and few sac-fry have been observed.


No O. mykiss were captured during this reporting period.


Instantaneous temperature taken at the trap ranged from 51.9F to 54.3F, and turbidity ranged from 1.11 NTU to 3.41 NTU. Daily average flow at La Grange (LGN) ranged between 1,900 cfs and 3,890 cfs (Figure 4).


Table 2. Biosampling data for Chinook salmon captured and measured at Waterford between December 3 and December 12, 2010. Parentheses indicate range.

Catch Table

 

 Flow and Catch

Figure 4. Daily Chinook salmon catch at Waterford and Tuolumne River flow recorded by La Grange (LGN) and Modesto (MOD), 2009.

 

 
2010/11 Stanislaus River Weir Monitoring 

Between November 22 and December 12 a total of 117 fall-run Chinook salmon were detected by the Vaki Riverwatcher as they passed upstream of the Stanislaus River weir, increasing the season total to 1,346 (Figures 5). Daily passage during this sampling period ranged from 0 to 17 Chinook (Figure 6). The number of Chinook passages observed so far this year represents a slight increase over the total passages observed last year (Table 3).

 

Instantaneous water temperature measured at the weir ranged between 45.8˚F and 55.2˚F, and daily average water temperature at Ripon (RPN; RM 15) ranged between 46.9˚F and 56.8˚F (Figure 7). Instantaneous turbidity ranged between 0.63 NTU and 2.87 NTU (Figure 8). Instantaneous dissolved oxygen at the weir ranged between 9.25 mg/L and 12.17 mg/L, and daily average dissolved oxygen at Ripon (RPN; RM 15) ranged from 8.93 mg/L to 11.53 mg/L (Figure 9).

 

Daily average flows in the Stanislaus River at Goodwin Dam (GDW; RM 58) remained stable between 201 cfs and 208 cfs. Flows at Ripon (RIP; RM 15) fluctuated between 237 cfs and 283 cfs. Note: flows downstream of Goodwin Dam may differ from dam releases due to irrigation, precipitation and other factors.

 

Table 3. Annual fall-run Chinook passage at the Stanislaus River weir prior to December 12, 2003-2010.
YTD Passage Table
Cummulative Chinook passage 2003-2010

Figure 5. Cumulative passage of fall-run Chinook salmon recorded at the Stanislaus River weir from 2003-2010.



Flow and Catch

Figure 6. Daily upstream Chinook passage 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) in 2010.

 
 
Temperature

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) in  2010.

turbidity and passage

Figure 8. Daily upstream Chinook passage at the Stanislaus River weir in relation to instantaneous turbidity recorded at the weir in 2010.


Dissolved Oxygen
Figure 9. Daily upstream Chinook passage 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) in 2010.


2010/10 Tuolumne River Weir Monitoring 
Tuolumne River weir removal
Figure 10. Tuolumne River weir removal.


The Tuolumne River weir was removed on November 30 in anticipation of increased flows due to flood control releases that were expected to exceed the maximum operational flow for the weir (>1,500 cfs)(Figure 10).


Between November 22 and November 30 a total of 82 Chinook salmon were detected by the Vaki Riverwatcher as they passed upstream of the Tuolumne River weir, increasing the season total to 766 (Table 4). Daily passage ranged from 1 to 28 Chinook (Figure 12). The number of Chinook passages observed so far this year has exceeded the total passage count observed last year (Figure 11).


Instantaneous water temperature measured at the weir ranged between 48.3˚F and 54.3˚F. Daily average water temperature at Modesto (MOD; RM 17) was not available during the reporting period (Figure 13). Instantaneous turbidity ranged between 0.76 NTU and 2.62 NTU (Figure 14), and instantaneous dissolved oxygen ranged between 7.79 mg/L and 10.07 mg/L (Figure 15).


Daily average flows in the Tuolumne River increased from 360 cfs to 3,890 cfs at La Grange (LGN; RM 50) and from 437 cfs to 4,510 cfs at Modesto (MOD; RM 17). Note: flows downstream of La Grange may be higher than dam releases due to accretion and Dry Creek inflow.


Table 4. Annual fall-run Chinook passage at the Tuolumne River Weir, 2009 and 2010.

YTD Passage Table

Cummulative Chinook passage 2009-2010

Figure 11. Cumulative passage of fall-run Chinook salmon recorded at the Tuolumne River weir in 2009 and 2010.



Chinook passage and flow

Figure 12. Daily upstream Chinook passage 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) and Maze Road Bridge (MRB) in 2010. 


Temperature

Figure 13. Daily upstream Chinook passage 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 Maze Road Bridge (MRB), Vernalis (VER), Mossdale (MSD) and Rough & Ready (RRI) in 2010.

 
turbidity and passage

Figure 14. Daily upstream Chinook passage at the Tuolumne River weir in relation to instantaneous turbidity recorded at the weir in 2010.


Dissolved Oxygen

Figure 15. Daily upstream Chinook passage 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) in 2010.


 
Merced River Conditions 

CDFG reported that 2 salmon were spawned at Merced River Fish Facility during the week of December 6increasing the season total to 42. During carcass surveys conducted the week of December 6, a total of 35 live Chinook and 87 redds were observed.

During the reporting period, flows in the Merced River at Cressy (CRS; RM 52) are only available for ten days during the reporting period but were stable between 206 cfs and 241 cfs, and at Stevinson (MST; RM 5) ranged from 322 cfs to 372 cfs (Figure 16). Water temperatures in the Merced River ranged from 47.5F to 53.6F at Cressy, and from 45.4F to 55.9F at Stevinson (Figure 17).

Flow 

Figure 16. Daily average flows (cfs) recorded in the Merced River at Cressy (CRS) and Stevinson (MST) in 2010.

Temperature

Figure 17. Daily average water temperatures (F) recorded in the Merced River at Cressy (CRS) and Stevinson (MST) in 2010.


 
San Joaquin Basin Escapement Surveys


Annual carcass surveys conducted by CDFG continued during the week of December 6. The largest number of live fish was observed on the Stanislaus River (48 fish), while 35 live fish were observed on the Merced River. Flows are high on the Tuolumne River and visibility is poor, therefore no escapement surveys could be conducted.

The number of redds decreased during the reporting period with 74 redds observed on the Stanislaus River and 87 on the Merced River.


 
Mokelumne River Woodbridge Dam Fish Ladder Monitoring
 
Fall-run Chinook salmon returning to the Mokelumne are counted annually by East Bay Municipal Utility District (EBMUD) as they ascend the fish ladder at Woodbridge Dam. As of December 12, a total of 7,052 Chinook have passed upstream of the dam this season (Figure 18).
 
Chinook passage and flow 

Figure 18. Daily upstream Chinook passage recorded at the Woodbridge Dam fish ladder in relation to daily average flows (cfs) recorded in the Mokelumne River at Camanche Reservoir (CMN) in 2010. Note: Graph does not include fish observed before September 22.


 
San Joaquin Conditions

During the reporting period, flows increased in the San Joaquin River at Vernalis ranging from 1,761 cfs to 5,288 cfs (Figure 19). Water temperatures in the San Joaquin River fluctuated between 47.1F and 54.7F at Vernalis, between 47.5F and 55.4F at Mossdale, and between 51.0F and 57.5F at Rough 'n Ready Island (Figure 20). Average daily dissolved oxygen (DO) in the San Joaquin River fluctuated from 8.0 mg/L to 9.1 mg/L in the deep water ship channel (measured at Rough 'n Ready Island), and between 8.9 mg/L and 10.9 mg/L at Mossdale (Figure 21).


Flow 
 Figure 19. San Joaquin River flows at Vernalis from December 1, 2009 through December 12, 2010.


Temperature

Figure 20. San Joaquin River daily average water temperatures at Vernalis, Mossdale, and Rough 'n Ready from December 1, 2009 through December 12, 2010.

Dissolved Oxygen

Figure 21. San Joaquin daily average dissolved oxygen at Mossdale and Rough 'n Ready, from December 1, 2009 through December 12, 2010.



Delta Exports

Mean daily pumping at the C.W. Jones Pumping Plant (federal pumps previously known as Tracy Pumping Plant) remained relatively stable during the reporting period and fluctuated between 4,062 cfs and 4,139 cfs (Figure 22). Mean daily pumping at the Harvey O. Banks Pumping Plant (state pumps) ranged between 4,489 cfs and 6,369 cfs. Combined total exports (state and federal pumps) during this period ranged from 8,551 cfs to 10,508 cfs.

Exports

Figure 22. Daily exports at the state and federal pumping stations from December 1, 2009 through December 12, 2010.