California Department of Fish and Wildlife

Monthly Abundance Indices

Fall Midwater Trawl indices for age-0 striped bass (Morone saxatilis), delta smelt (Hypomesus transpacificus), longfin smelt (Spirinchus thaleichthys), American shad (Alosa sapidissima),splittail (Pogonichthys macrolepidotus), and threadfin shad (Dorosoma petenense) from 1967-2015; please note that no surveys were done in 1974, 1979, and September and December 1976.

The September 1976 index was calculated by taking a quotient of the respective September and October indices (September/October) for pre-Corbula amurensis years 1967-1973, 1975, 1977-1978, 1980-1987 then averaging the quotients.

This mean quotient was then multiplied by the respective 1976 October index to generate the September index. The 1976 December index was calculated for each species by averaging the 1976 November and 1977 January indices.

In addition, due to the low number of stations sampled in Nov. 1969, the 1969 Nov. index is the average of the October and December 1969 index.

Mulitple Table View

Age-0 Striped Bass

YearSeptOctNovDecTotal
19671194136811789226619677
1968163311606023243719
196938941548139312378072
197022771817275014328276
197139921837135122959475
1972316097413776056116
19731516441100513244286
1974
1975177268112848114548
19762391172438211420
1977307204180192883
197811155613365862598
1979
19807393841022681493
1981583916103719954531
1982147693893911134466
1983193419945272327312473
198412872666137412546581
1985125825587521760
198627065325081973943
19876031692063721350
198810698129144477
19891541527660442
19902342353974541320
1991262128115439944
19926202465446322042
19935085132812541556
19942061882066591259
199511613114190478
1996714632243392
19972871436969568
19982342901265741224
199915468134185541
2000931549051388
2001181217114219731
20021820152073
200334342518111
2004161761554
200540292626121
2006236183970363
2007323414282
200857398539220
2009923142470
2010165111143
2011112623068272
201220161475125
2013185133470
20148244559
201548112952
Delta Smelt (all ages)

YearSeptOctNovDecTotal
19679415731126408
196823525212386696
1969148785532313
1970742342825071673
19711974714282071303
1972572470811421265
19733083121983271145
1974
197529021410291697
19766942121127359
1977982425288480
19781676531309572
1979
19803702745874231654
19811322754161374
1982454779162333
19832287824132
198447446724182
198541242817110
198692153471212
1987714069100280
198858671930174
1989887515845366
19901095018817364
199112624927935689
19927235724156
1993375470941391078
19946512718102
199512034935278899
199619231372127
19971510971108303
1998238971570420
1999198380114172864
200043012856142756
2001754811730603
200220462944139
2003151361742210
2004261823774
2005397726
20063334141
20079451028
20082512423
20091331017
201061201129
2011505423216343
201202312742
2013432918
201444019
201550027
Longfin Smelt (all ages)

YearSeptOctNovDecTotal
196715484499927480878181737
196814087714466543279
19693579798457851585759350
1970889410105641606515
1971238857225019277415903
1972138118106398760
19732794123780810575896
1974
197531859811987052819
1976151290541658
197729178381210
197817441173145022526619
1979
19801523360713526635431184
198122239817914032202
1982789813961281711287562905
198315231065407319911864
19843282612255119177408
19852031219722992
19869721543185717886160
1987134703849321520
19881617207551791
1989113237376456
199010181151243
1991872792134
199230126176
199399112128459798
199441079452545
1995543093115163288205
19962271413031346
199710651194339690
19981491578203228956654
1999195327363312235243
20001635489388163437
2001744627100247
2002127144182254707
2003106277318467
20044499129191
20051221393129
20061563169184331949
2007202913
20080194377139
200908104765
2010274178191
2011681692301477
201262173661
201382821107164
2014635216
201500044

American Shad (all ages)

YearSeptOctNovDecTotal
1967151910916072053422
196827427713770758
1969132011777894023688
197036625417066856
19713514733802551459
19721405610930335
1973599193211821085
1974
197512405874861782491
1976956910280346
1977126147233130636
197876210603212212364
1979
1980129516975234013916
19812865223492771434
19822245160913252105389
19839628529581592931
198429217226786817
19853163325643861598
19866945673132861860
1987261292222124899
19888053103001351550
19895693395923781878
1990149394713695074316
199110767798722602987
19927555304632662014
1993197215679087105157
19944393873911171334
1995324622207915556812
1996175610729355234286
199726556563911252594
1998131820935152144140
199934615514569715
200025332612659764
200133823911078765
20023728323343821920
200333452947127917899360
20046808378106947
20058265521771891744
200611191426464062313
200712325711657553
2008142519213271
20098175252216624
201013054114385683
2011413204142135894
201213514134105415
201374618688309
2014461772143278
2015612223979
Splittail (all ages)

YearSeptOctNovDecTotal
196743103965
1968673218
19697117328
19701302217
1971458118
1972301913
197320204
1974
197521014
197600112
197700000
197814164337
1979
19801141016
1981933318
198276201211119
198354266311154
19841014116
1985340815
1986142581158
198710341229
198834209
198931004
199052108
19911026018
199220103
1993431210
199401023
199543275176
19961300922
199710001
1998127924517281
199924312039
200004318
200110201527
200200101
200345009
200412104
200550005
200610304
200710001
200800000
200900011
201000000
20111500015
201200011
201300011
201400011
201500000
Threadfin Shad (all ages)

YearSeptOctNovDecTotal
196768103640928135712735
19681631157016186145433
1969591511468285098398
197015968207868614063
19711064347317596106906
19721527185811066225113
1973104346113301232
1974
197529224267135718
197615854213236282957
19772703284728975699016
19789844811494852099
1979
19801243402314725417279
19811164342818232596674
198230437511972252101
19835835876532652088
198434611327820757
198527825860225821
19867423421657882829
19878917219845283475
198840928715551582409
1989180856442093166897
1990405898171028465859
199163142013998663316
199274210543717912958
19931521253719276936678
19943318198363192305
199516315927303843337
1996146115093425284758
199779735436140478715267
1998192220709597975748
19992670772239216937527
20006818791218981212977
2001438216161407699614401
200213710242533171731
20037483393804971964
20046101793301821301
2005287114110094282865
200618521401211122225
2007801304429233177
2008592936632450
200928132043
20103736344120
201167205289228
201253112241
201396139168277
201418117588282
201519482277253806