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3792

2000 Fall-Run Chinook Salmon SpawningEscapement in the Yuba River

Prepared for:

Yuba County Water Agency1402 D Street

Marysville, CA 95901Contact: Curt Aikens

530/741-6278

Prepared by:

Jones & Stokes2600 V Street

Sacramento, CA 95818-1914Contact: Stephanie Theis

916/737-3000

June 2001

UBRi\RY COpy

Contents

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Introduction........................................................................................ 1Methods 1Results 3

River Conditions 3Spawning Escapement, Timing, and Distribution 4Run Composition ; 5Hatchery Fish 5Recovery Rates 5

Recent Trends in Abundance 6References Cited 7

Printed References 7Personal Communications 8

2000 Fall-Run Chinook Salmon SpawningEscapement in the Yuba River

June 2001

J&S 00402

,

Figures

Figure Follows Page

1 Lower Yuba River Chinook Salmon SpawningEscapement Survey Reaches 2

2 Length Frequencies of Fish Collected in the FirstThree Weeks of Surveys 4

3 Daily Yuba River Flows Measured at the Smartvilleand Marysville Gages,September 1-December 25, 2000 4

4 Mean Daily Yuba River Water TemperaturesMeasured at Parks Bar, Smarville, and Marysville,September 1-December 25,2000 4

5 Weekly Counts of Fresh Salmon Carcasses bySurvey Reach, 2000 6

6 Annual Fall-Run Chinook Salmon SpawningEscapement in the Lower Yuba River during Pre­(1953-1971) and Post- (1972-2000) New BullardsBar (NBB) Reservoir Periods 6

7 Annual Hatchery and Natural SpawningEscapement of Sacramento River Chinook Salmon 6

2000 Fall-Run Chinook Salmon SpawningEscapement in the Yuba River iii

June 2001

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,

IntroductionFrom 1953 to 1989, the California Department of Fish and Game (DFG)conducted annual surveys of chinook salmon carcasses on the lower Yuba Riverto estimate fall-run chinook salmon (Oncorhynchus tshawytscha) spawningescapement (i.e., the number of salmon that return to spawn each year). Becauseof budget cuts, DFG suspended its surveys of Yuba River salmon carcasses in1990. In response, the Yuba County Water Agency (YCWA) retained Jones &Stokes in 1991 to conduct the escapement surveys and has continued thesesurveys each year since. DFG assisted Jones & Stokes from 1992 through 1994,but was unable to participate in subsequent years.

The objectives of these surveys are to estimate total chinook salmon run size inthe lower Yuba River (downstream of Eng1ebright Dam). Additional informationobtained from the surveys includes run timing, spawning distribution, proportionof adults (age 3 and older) and grilse (age 2), and the proportion of males andfemales.

This report presents the results of the 2000 spawning escapement surveys. Theresults of the 1991-1999 surveys were reported in previous documents (Jones &Stokes Associates 1992-2000).

MethodsFrom 1973 to 1989, DFG used a modified form of the Schaefer mark-recoverymethod to estimate the number of chinook salmon that spawn each year in theYuba River (Schaefer 1951). The Schaefer method is a mark-recapture techniquedesigned to estimate the number of fish in a population as a series of distinctunits separated either spatially or temporally. The sampling methods used duringthe 2000 spawning escapement surveys on the Yuba River were generallyconsistent with those used by DFG during past surveys with a few modifications.

Weekly carcass surveys were conducted during the principal spawning season forfall-run chinook salmon, from October 3,2000, to December 21,2000, in thefollowing reaches (figure 1 and appendix B):

• Rose Bar (Rose Bar at the downstream end of the narrows to Parks Bar at theHighway 20 bridge),

• Parks Bar (Highway 20 Bridge to Daguerre Point Dam), and

• Daguerre (Daguerre Point Dam to the Simpson Lane bridge in Marysville).

These reaches include nearly all of the spawning areas used by chinook salmonin the Yuba River. Spawning may occur in the narrows between Rose Bar andEnglebright Dam, but spawning gravel is scarce in this reach. For many years,DFG did not survey the reach above Parks Bar. Instead, DFG assumed that15.5% of the run spawned above Parks Bar. This figure was based on the

III

2000 Fall-Run Chinook Salmon SpawningEscapement in the Yuba River

June 2001

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Escapement Survey Reaches

River Conditions

Results

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tagged with white flagging and treated as a chopped fish). Decomposedcarcasses that were found in the water were placed back in the water, while thosecarcasses found up on the banks were left on the banks. Previously tagged fishwere also counted and chopped, and then marked as recovered fish, specifyingthe color of the tag.

Weekly population estimates were computed based on the proportion of taggedcarcasses recovered and the total number of tagged and untagged carcassesobserved. Weekly estimates were added together to obtain the total spawningescapement estimate.

Separate population estimates for adult male and female chinook salmon werenot possible because of the difficulty in determining the sex of highlydecomposed carcasses (both tagged and untagged) during tag recovery efforts.Therefore, the sex composition of adult salmon was based on the proportion ofmales and females observed weekly among fresh carcasses. Attempts todistinguish between male and female grilse by external characteristics were notreliable enough to separate, although most of the smaller salmon are typically age2 males.

Salmon carcasses were classified as adults if they were greater than 25.5 incheslong (fork length), or as grilse if they were less than 25.5 inches long. Thiscutoff length was determined from length-frequency data acquired from thechinook salmon collected on the Yuba River in the beginning of the 2000 season(figure 2). The length-frequency distribution indicated that the 25.5-inch cutofflength was a reasonable criterion, although there was apparently some overlap inadult and grilse lengths.

Streamflows, water temperature, and water clarity were monitored during thespawning escapement surveys to examine the relationship of these variables tospawning timing and distribution. Telemetered daily flow data were obtainedfrom the U.S. Geological Survey (USGS) gage below Englebright Dam nearSmartville, California (Station 11418000), and the USGS gage near Marysville,California (Station 11421000). Water temperature was recorded hourly usingOnset optic stowaway recording thermometers placed near the USGS Smartvillegage, at the Highway 20 bridge crossing, Daguerre Point Dam, and near theUSGS gage near Marysville. Water clarity was visually estimated each day thatthe survey was conducted.

Figure 3 presents the daily average Yuba River flows during the 2000 chinooksalmon spawning season. Yuba River flows below Englebright Dam (Smartvillegage) ranged between 967 and 1089 cubic feet per second (cfs) during the surveyperiod, and were relatively stable throughout the spawning season. Yuba River

June 2001

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Figure 2Length Frequencies of Fish

Collected in the First Three Weeks of Surveys

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Figure 4Mean Daily Yuba River Water Temperatures Measured

at Parks Bar, Smartville, and Marysville,September 1 - December 25, 2000

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Figure 3Daily Yuba River Flows Measured at the Smartville and

Marysville Gages, October 1 - December 25, 2000

Oct 1 Oct6 Octll Oct 16 Oct21 Oct26 Oct31 Nov5 Nov10 Nov 15 Nov 20 Nov 25 Nov 30 Dec5 DeclO Dec 15 Dec 20 Dec 25

Survey Date (2000)

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Run Composition

Recovery Rates

Hatchery Fish

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remained fairly constant between September and December, in the low 50s.Water temperatures at the Marysville gage (approximately 6.8 miles downstreamof Daguerre Point Dam) reached 60°F in early October, but quickly dropped bymid-October to the mid- to low 50s. Spawning peaked in the 2nd and 3rd weeks ofOctober in the Rose Bar Reach. Spawning peaked in the 3rd and 41h weeks ofOctober and the 1st week of November in the Parks Bar Reaches. Spawningpeaked in the 151 week of November in the Daguerre Reach after temperaturesdropped to 55°F or below (figure 5).

The Rose Bar Reach is approximately 3.99 miles long. An estimated 30.8% ofthe run (4,575 fish) spawned in the Rose Bar Reach (table 1); therefore, about1,147 fish spawned per mile.

The Parks Bar Reach is approximately 6.34 miles in length. An estimated 39.5%of the run (5,860 fish) spawned in the Parks Bar Reach (table 1); therefore, about924 fish spawned per mile.

The Daguerre Reach is approximately 9.22 miles long; however, the lowerportion of the surveyed reach (generally from the city dump downstream toSimpson Lane) is relatively deep with fine-grained sediments that are generallyunsuitable for spawning. About 6 miles of the surveyed portion of this reachcontain spawning habitat. An estimated 29.7% of the run (4,417 fish) spawned inthe Daguerre Reach; therefore, about 773 fish spawned per river mile.

Adult male and female salmon comprised 46% and 54%, respectively, of thefresh adult carcasses observed during the 2000 surveys (table 1). Grilse salmoncomprised 12.4% of the total number of fresh carcasses and 13% of the totalestimated population. The sex of grilse could not be reliably determined in thefield, but typically the majority of grilse are male. Spring-run chinook salmonmay have been included in the surveys because there is no way to visuallyseparate the 2 runs of chinook salmon.

Five coded-wire-tagged salmon were recovered from the Yuba River during the2000 surveys and delivered to DFG for decoding. All the hatchery fish wererecovered by the end of November. The tags have not been deciphered at thetime of publication.

The weekly recovery rates of tagged adult salmon carcasses (i.e., the percentageof tagged carcasses that were recovered) averaged 44% in the Rose Bar andParks Bar Reaches and 42% in the Daguerre Reach, with an overall recovery rate

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I m Jones & Stokes Figure 5Weekly Counts of Fresh Salmon Carcasses

Iby Survey Reach, 2000

Table 2. Annual Fall-Run Chinook Salmon Spawning Escapement in the Yuba River duringPre- (1953-1971) and Post- (1972-Present) New Bullards Bar Reservoir Periods

9,25824,11917,8095,6413,7798,7227,416

12,43012,40614,02539,36714,2569,965

13,06619,40618,5108,5019,837

no survey14,4136,3616,516

10,69114,56127,52025,77830,80223,06714,85215,110

19721973197419751976197719781979198019811982198319841985198619871988198919901991199219931994199519961997199819992000

Average12906

6,0005,0002,0005,0001,0008,000

10,00020,0009,000

34,00037,00035,00010,0008,000

23,5007,0005,230

13,8305,650

Pre-Reservoir Escapement Year__Post-Reservoir EscapementYear1953195419551956195719581959196019611962196319641965196619671968196919701971

AverageSources:1953-1966: Hallock (n.d.)1967-1989: Mills and Fisher (1994)1991-1999: Jones & Stokes Associates (1992-2000)

----------------~--

Pre-New Bullards Bar Reservoir Post-New Bullards Bar Reservoir

~erage = 15,110 a I

\ !Average=14,421 bj~53-1971 Average = 12,9061\\1

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a Average post-NBB spawning escapement based on actual estimates of spawningescapement in Rose Bar reach in 1994 and 1995-2000 (dark bars).

b Average post-NBB spawning escapement based on assumptions that 15.5% of spawningescapement spawned in Rose Bar reach in 1994 and 1995-2000.

LEGENDIIiM@lllil Estimated Count_ Actual Count

SOURCES:1953-1966: Hallock (n.d.)1967-1989: Mills and Fisher (1994)1991-2000: Jones & Stokes Associates (1992-2000).

mJones & Stokes Figure 6Annual Fall-Run Chinook Salmon Spawning Escapement

in the Lower Yuba River during Pre- (1953-1971) andPost- (1972-2000) New Bullards Bar (NBB) Reservoir Periods

-------------------

2000199519901985

Year

19801975

50,000

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100,000

450,000 i I

400,000 f-I------------------------------------------

300,000

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o1970

SOURCE:Pacific Fishery Management Council (2001)

m Jones & Stokes Figure 7Annual Hatchery and Natural Spawning Escapement

of Sacramento River Chinook Salmon

Printed References

References Cited

I

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Boydstun, L. B. 1994. Analysis of two mark-recapture methods to estimate thefall chinook salmon (Oncorhynchus tshawytscha) spawning run in BogusCreek, California. California Fish and Game 80(1):1-13.

Hallock, R. J. n.d. Status of the Sacramento River system salmon resource andescapement goals. California Department of Fish and Game. Red Bluff, CA.

Jones & Stokes Associates. 1992. 1991 fall-run chinook salmon spawningescapement in the Yuba River. June. (JSA 91-219.) Sacramento, CA.Prepared for Yuba County Water Agency, Marysville, CA.

____. 1994. 1992fall-run chinook salmon spawning escapement in theYuba River. February. (JSA 91-219.) Sacramento, CA. Prepared for YubaCounty Water Agency, Marysville, CA.

____. 1995. 1993 and 1994 fall chinook salmon spawning escapements inthe Yuba River. February. (JSA 94-223.) Sacramento, CA. Prepared forYuba County Water Agency, Marysville, CA.

_____. 1996. 1995fall chinook salmon spawning escapements in theYuba River. July. (JSA 95-076.) Sacramento, CA. Prepared for YubaCounty Water Agency, Marysville, CA.

____. 1997. 1996 fall chinook salmon spawning escapements in theYuba River. July. (JSA 95-076.) Sacramento, CA. Prepared for YubaCounty Water Agency, Marysville, CA.

____. 1998. 1997fall-run chinook salmon spawning escapements in theYuba River. June 12, 1998. (JSA 97-238.) Sacramento, CA. Prepared forYuba County Water Agency, Marysville, CA.

_____. 1999. 1998fall-run chinook salmon spawning escapements in theYuba River. March 23, 1999. (JSA 97-238.) Sacramento, CA. Prepared forYuba County Water Agency, Marysville, CA.

_____. 2000. 1999fall-run chinook salmon spawning escapements in theYuba River. August 2000. (J&S 97-238.) Sacramento, CA. Prepared forYuba County Water Agency, Marysville, CA.

Mills, T. J., and F. Fisher. 1994. Central Valley Anadromous Sport Fish AnnualRun-size, harvest estimates, and population trends, 1967-1991. InlandFisheries Technical Report. California Department of Fish and Game.Sacramento, CA.

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- - - - - - - - - - - - - - - - - - -Table B-1. Weekly Recoveries of Adult Salmon Carcasses in the Rose Bar Reach, 2000

Tagged TotalWeek of Week of Tagging (i) Carcasses CarcassesRecovery Recovered Recovered

(j) Oct 3 Oct 10 Oct 17 Oct 24 Oct 31 Nov 7 Nov 14 Nov 20 Nov 28 Dec 5 Dec 12 (Rj) (Cj)Oct 10 4 4 104Oct 17 1 15 16 308Oct 24 0 4 46 50 470Oct 31 0 0 4 37 41 325Nov 7 0 0 4 5 26 35 307

Nov 14 0 0 0 4 5 28 37 221Nov 20 0 0 0 0 0 0 5 5 89Nov 28 0 0 0 0 1 4 10 5 20 110Dec 5 0 0 0 0 0 0 1 1 4 6 61

Dec 12 0 0 0 0 0 1 3 0 2 2 8 70

Tagged CarcassesRecovered (Ri) 5 19 54 46 32 33 19 6 6 2 0 222

Total CarcassesTagged (Mi) 10 40 120 118 76 57 36 19 15 10 7 508

Ri/Mi 0.50 0.48 0.45 0.39 0.42 0.58 0.53 0.32 0.40 0.20 0 0.44

Table B-2. Weekly Population Estimates of Adult Salmon in the Rose Bar Reach, 2000

Week of Week of Tagging (i)Recovery

(j) Oct 3 Oct 10 Oct 17 Oct 24 Oct 31 Nov? Nov 14 Nov 20 Nov 28 Dec 5 Total

Oct 10 208 208Oct 17 39 608 647Oct 24 0 79 961 1040Oct 31 0 0 70 752 822Nov 7 0 0 78 113 542 733

Nov 14 0 0 0 61 71 289 421Nov 20 0 0 0 0 0 0 169 169Nov 28 0 0 0 0 0 38 104 87 229Dec 5 0 0 0 0 0 0 19 32 102 153Dec 12 0 0 0 0 0 15 50 0 44 88 197

Total 247 687 1109 926 613 342 342 119 146 88 4619Adj. Total 4138

- - - - - - - - - - - - - - - - - - -Table B-5. Weekly Recoveries of Adult Salmon Carcasses In the Parks Bar Reach, 2000

lagged lotalWeek of Week of Tagging (i) Carcasses CarcassesRecovery Recovered Recovered

0) Oct 4 Oct 11 Oct 18 Oct 26 Nov 1 Nov 8 Nov 15 Nov 21 Nov 29 Dec 6 Dec 13 (Rj) (Cj)

Oct 11 9 9 103Oct 18 3 11 14 215Oct 26 0 1 20 21 385Nov 1 0 1 12 31 44 437Nov8 0 0 0 10 35 45 445Nov 15 0 0 4 0 10 25 39 451Nov 21 0 0 2 0 2 9 29 42 244Nov 29 0 1 0 3 1 2 6 2 15 108Dec 6 0 0 0 1 0 2 1 3 3 10 96Dec 13 0 0 0 0 0 0 0 0 0 0 0 44

Tagged CarcassesRecovered (Ri) 12 14 38 45 48 38 36 5 3 0 239

Total CarcassesTagged (Mi) 24 38 65 92 106 82 74 32 18 11 542

Ri/Mi 0.50 0.37 0.58 0.49 0.45 0.46 0.49 0.16 0.17 0.00 0.44

Table B-6. Weekly Population Estimates of Adult Salmon In the Parks Bar Reach, 2000

Week of Week ofTagging (i)Recovery

---------_._-

0) Oct 4 Oct 11 Oct 18 Oct 26 Nov 1 Nov 8 Nov 15 Nov 21 Nov 29 Dec 6 Total

Oct 11 206 206Oct 18 92 459 551Oct 26 0 50 627 677Nov 1 0 27 204 629 860Nov 8 0 0 0 202 764 966Nov 15 0 0 79 0 255 624 958Nov 21 0 0 20 0 26 113 346 505Nov 29 0 0 0 44 16 31 89 92 272Dec 6 0 0 0 20 0 41 20 184 173 438

Dec 13 0 0 0 0 0 0 0 0 0 0 44

Total 298 536 930 895 1061 809 455 276 173 0 5477Adj. Total 4970

- - - - - - - - - - - - - - - - - - -Table 8-9. Weekly Recoveries of Adult Salmon Carcasses in the Daguerre Point Reach, 2000

Tagged TotalWeek of Week of Tagging Carcasses CarcassesRecovery Recovered Recovered

0) Oct 12 Oct 19 Oct 27 Nov 2 Nov 9 Nov 16 Nov 23 Nov 30 Dec 7 Dec 14 Dec 21 (Rj) (Cj)

Oct 19 0 0 35Oct 27 0 5 5 111Nov2 2 1 14 17 187Nov 9 0 0 0 16 16 268

Nov 16 0 0 0 18 12 30 354Nov 23 0 0 0 3 0 13 16 206Nov 30 0 0 0 0 2 7 14 23 223Dec 7 0 0 0 1 2 3 2 10 18 147

Dec 14 0 0 0 0 0 0 0 1 6 7 102Dec 21 0 0 0 0 0 0 0 0 0 2 2 50

Tagged CarcassesRecovered (Ri) 2 6 14 38 16 23 16 11 6 2 6 140

Total CarcassesTagged (Mi) 9 16 38 72 60 52 38 27 15 9 336

Ri/Mi 0.22 0.38 0.37 0.53 0.27 0.44 0.42 0.41 0.40 0.00 0.42

Table 8-10. Weekly Population Estimates of Adult Salmon In the Daguerre Point Reach, 2000

Week of Week of TaggingRecovery

----

0) Oct 12 Oct 19 Oct 27 Nov 2 Nov 9 Nov 16 Nov 23 Nov 30 Dec 7 Dec 14 Dec 21 Total

Oct 19 0 35Oct 27 0 296 296Nov 2 99 29 418 546Nov 9 0 0 0 508 508

Nov 16 0 0 0 402 531 933Nov 23 0 0 0 73 0 378 451Nov 30 0 0 0 0 73 153 322 548Dec 7 0 0 0 0 61 55 39 200 355

Dec 14 0 0 0 0 0 0 0 36 219 255Dec 21 0 0 0 0 0 0 0 0 0 225 225

Total 99 325 418 983 665 586 361 236 219 225 4152Adj. Total 3816

3792 00-4022000 Fall-Run Chinook Salmo]Spawning Escapement in theYuba River

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Jones & Stokes. 2001. 2000 Fall-run chinook salmon spawning escapement inthe Yuba River. June 2001. (J&S 00-402.) Sacramento, CA. Prepared forYuba County Water Agency, Marysville, CA.