p. 1 4. 0 Entrainmen t an d Source Wate r Results 

### Th e Harbor

Mouth , Ocea

n North , an

dOcea n Sout h station s wer

e no t sample di n June , July , or August . Generally concentration s o f undentifie dgobie s wer

e lo w a t th e Ocea n Stations . The Ocea n Nort h Statio n ha

dn o unidentifie dgobie s collecte di n Septembe

r an dOctober

and concentration s o

f 73/1,00 0 m 3 

### wer

e reache di n Februar y 200 0 durin g high tide . Unidentifie d gobie s wer

e collecte da

t th e Ocea n Sout h Statio n i n low concentration s (les s tha n 15/1,00 0 m3 

### ) durin g th e September , October , November , an dDecembe

r survey s durin g high tide . I n Januar y andFebruar

y 2000 , concentration s increase da t the Ocea n Sout h Statio n t o apea k o f 209/1,00 0 m 3 

### durin g alow tid e o n Februar y 24 , 2000 . Datafro mth e sourc e wate

r survey s show tw o seasona

l peak s i n unidentifie dgob y concentrations . Th e highes t concentratio n i

n the Elkhor

n Sloug h station s occurre da

t Kirby Par k i n Jun e 199 9 (2,913/1,00 0 m 3 

### ) during hig

h tide . Othe

r hig h concentration s occurre ddurin g a hig h tide a t th e Harbor

Bridg e Station i

n Novembe

r 199 9 (1,940/1,00 0 m3 

### ) anda t alow tide (concentratio n = 1,721/1,000 m) i n Februar y 2000 . Thes e distinc t

seasona l peak s ma

y indicat e spawnin g b y tw o specie s o

f goby . The pea

k concentratio n a

t Kirby Par k als o coincide dwit

h a pea k i n ba y goby concentrations . I

t i s possibl e tha

t thes e unidentifie dgobie s ma y b e ba y gob y tha t wer e to o small to identif

y t o species . Similaritie s i

n concentratio n increase s between ba y goby andunidentifie dgobie s als o occurre di n Novembe

r a t th e Harbor

Bridge , Harbor

Mouth , Ocea n North , an

dOcea n Sout h stations . Unidentifie dgobie s wer

e the secondmos t

abundantly entraine dlarva l fishe s collecte di

n the first entrainmen

t samplin g progra

mfro mNovembe

r 197 8 through March 198 0 (PG&E , 1983) . Taxonomi c separation s wer e not mad e within th e Family Gobiida e excep t fo r longja w mudsucker . It

wa s though

t tha t thes e unidentifie dgobie s wer e probably arro w goby , ba

y goby , andyellowfin gob y Acanthogobius flavimanus. Highes t

concentration s o

f 1,200/1,000 m 3 

### wer

e collecte din Januar

y 198 0 a t Unit s 1 through 5 (PG&E , 1933) .

E9-053. 9 4-3 4 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P. 2

4. 0 Entrainmen t an d Sourc e Wate rResult s 

## 4. 4 Ba y Goby Photographer : Nei l McDanie l



### Lepidogobius

lepidus

Range: Fro mCedro s Island . Baj aCaliforni at o

Vancouve r

Island , Britis h Columbia . Life History: Size : t o 10 8 m m(4.2 5 in.) ; ag e a

t maturity : on e t o tw o year s old ; fecundity : limite d informatio n available ; lifespan : seve n plu s years . Habitat: Intertida l mudflats , shallo w pools . Fishery: None . Distributio n Map fo

r Bay Gob y Th e bay gob y Lepidogobius lepidus i s acommo n bottom-dwellin g inhabitan t o f bay s an d estuarie s alon g th e Pacifi c coas t o f Nort h America . The y rang e fro mVancouve r Island , Britis h Columbi ato Cedro s Island , Baj aCaliforni a(Mille r an d Lea , 1972) . Bay gob y wer e th e mos t abundan t gob y specie s collecte dbetwee n 198 0 t o 199 2 durin g traw l survey s conducte d i n Sa n Francisc o Ba

y b y th e Californi aDepartmen t of Fis h an d Gam e (CDFG) . Th e bay gob y i s generall y considere dashallow-wate r marin e specie s bu

t ma y occu r o n mu d an d mud-san d substrate s dow n t o depth s o f 6 1 m(20 0 ft. ) (Mille r

an d Lea , 1972) . The y ar e commo n o n intertida l mudflat s wher e the y remai n i n invertebrat e burrow s an d shallo w pool s whe n th e tid e i s ou t (Grossman , 1979) . Lik e man y marine-estuarin e specie s the y are toleran t o f variation s i n salinit y an dtemperature . Durin g populatio n monitorin g studie s i n th e Sa n Francisc o Bay

E9-053. 9 4-3 5 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P. 3 

# 3

« y



# I 4. 0 Entrainmen t an d Sourc e Wate rResult s

Estuar y ba y gob y occasionall y (durin g period s o f lo w Delt aoutflow ) move d fro mmarin e waters , upstrea mthroug h th e Carquine z Strait s int o th e lowe r salinit y water s o f

Suisu n Ba y (CDFG , 1999) . Th e ba y gob y i s arelativel y small , elongat e specie s tha t reache s atota l lengt h (TL ) o f abou t 10 8 mm(4.2 5 in. ) (CDFG , 1999) . Ba y gob y vary fro mligh t olive-gree n t o tan o r

brow n i n colo r wit h dark reddish-brow n o r

brow n dorsa l mottling . Ventrall y the y hav e auniformlighte r coloration . The y generall y hav e ablack-edge d first dorsa l fin. Scale s ar e smal l an d cove r th e bod y an dposterio r

portion s o f

th e hea d (Hart , 1973) . The y hav e amoderate-size d termina l mouth an dablun t

snou t (Hart , 1973) . A s with othe r gob y specie s thei r

pelvi c fins ar e fused , formin g ahollo w cone . Ba y gob y ar e reporte d t o liv e for 7 year s o r

more , whic h i s considere d unusua l longevit y for

asmal l fish specie s (Grossman , 1979) . Lif e span estimate s o f

2 t o 3 year s hav e bee n derive dfro mlengt h frequenc y dat acollecte d b y CDFG . Base do n difference s i n ov asize/developmen t fro mfis h collecte d durin g Apri l an d Ma y of f Hunter s Poin t

Powe r Plan t i n San Francisc o Ba y an d i n Mos s Landin g Harbor , ba y gob y hav e bee n characterize da s asynchronou s multipl e spawner s (Wang , 1986) . Femal e ba y gob y appeare dt o becom e reproductivel y matur e at around4 0 mm(1. 6 in. ) (Grossman , 1979) . With th e exceptio n o f

afew gobie s tha t

matur e withi n thei r

first year , mos t

individual s withi n acohor t d o no t becom e reproductivel y matur e unti l thei r secondyear

(Wang , 1986) . Spawnin g occurre d i n Morr o Ba y fro mSeptembe r throug h March , with peak activit y occurrin g fro mJanuar y t o Marc h (Grossman , 1979) . Grossma n (1979 ) suggeste d tha t th e timin g o f

reproductio n i n ba y gob y ma y b e highl y variable . Littl e informatio n abou t th e detail s o f

ba y gob y spawnin g behavio r exist s in curren t

literature . Becaus e ba y gobie s us e invertebrat e burrow s fo r predato r avoidanc e an dt o stave-of

f dehydratio n durin g lo w tide s i t i s though t

tha t th e species , lik e man y othe r gob y species , ma y als o us e burrow s fo r spawnin g (Grossman , 1979 ; Wang , 1986) . N o fecundit y informatio n i s availabl e fo r ba y goby . Egg s ar e demersal , an d spherical/elliptica l i n shap e with a n adhesiv e anchorin g poin t (Wang , 1986) . Newl y hatche dlarva e ar e smal l ( 3 m m[0.1 2 in. ] o r less ) an d nearl y transparen t (Wang , 1986) . Literatur e suggest s tha t

ba y gob y hav e aplanktoni c lif e phas e o f

3 t o 4 month s (Grossman , 1979 ; Wang , 1986) . A 3 t o 4 month estimat e fo r th e pelagi c phas e corresponde d wel l wit h th e recruitmen t

model s (base do n gonada l maturit y inde x data ) fo r th e specie s develope d b y Grossma n (1979) . Thi s estimat e als o corresponde d wit h th e first appearanc e o f

settle d larva e i n Morr o Bay , Californi adurin g 1977 . Ba y gob y larva e occu r sympatricall y with th e larva e o f arro w gob y Clevelandia ios, cheekspo t gob y Ilypnus gilberti an d yellowfi n gob y Acanthogobius flavimanus i n Sa

n Francisc o Ba y an d with arro w gob y C . ios an d shado w gob y Quietula y-cauda i n Morr o Ba y (Wang , 1986 ; Grossman , 1979) . I n astud y b y Wan g (1986 ) mos t larva l ba y gobie s wer e collecte di n Sa n Francisc o Ba y fro mNovembe r throug h May , wit

h peak number s occurrin g i n Apri l an dMay . Th e greates t concentration s o f

larva l ba y gobie s withi n th e Sa n E9-053. 9 4-3 6 MLP P 316(b ) Resource Assessmen t 4-28-200 0P. 4

4. 0 Entrainmen t an d Source Wate r Result s 

### Francisc o Ba

y systemappeare dt o b e concentrate dbetwee n th e Golden Gat

e Bridg e andAngel Island(Wang , 1986) . A

t abou t 2 5 m mTL (0.9 8 in. ) ba

y gob y larvae settl e out

o f th e plankto n layer s t o begin ademersa

l existence . A leopard-spot-lik e patter n o f melanophore s form s abov e th e latera l lin e i n juvenile s aroundthe time the y descendt

o th e botto m(Grossman , 1979) . I n addition to thi s crypti c coloration , juvenile s (an dadults ) occup y th e burrow s o f blu e mud shrim

p Upogebia pugettensis, geoduck clam s Panope generosa an dother burrowin g animal s fo

r shelter an dpredato r avoidanc e (Grossman , 1979) . N o species-specifi c larva

l survivorship estimate s wer e availabl e fo

r ba y goby . However , Brother s (1975 ) calculate dlarva l mortalit y ove r two-months , post-hatchin g fo r thre e sympatri c gobiid s (arro w goby , cheekspo t goby , andshadow goby ) fro mMissio n Bay , California . Thes e estimate s wer

e usedt o approximat

e ba y gob y mortalit

y fo r earl y lif e stage s a s well a s post settlemen t juvenil e an

dadul t stages . Lac

k o f species-specifi c fecundit

y datapreclude d estimatio n o

f FH fo r thi s species , bu

t substitutin g survivorshi

p fro mthes e closel y relate d specie s fo r larval , juvenile , an

dadul t stage s allowedu s t

o project futur e losse s o f equivalent

adults . Juvenil e ba

y goby fee do n avariet y o f smal l crustacean s includin g copepod s andamphipods , a s wel l a s som e detrita l materia l (Wang , 1986) . Growt

h i s initially rapid , wit

h 5 0 percent

o f their tota l growt h (length ) occurrin g within th e first 2 year s (Grossman , 1979) . Followin g thi s perio d o f rapi dgrowth , increase s i

n lengt h slo w to abou

t 6 m m(0.24 in. ) pe r

yea r (Grossman , 1979) . Th e die t o f adul t ba y gobie s i s not

detaile di n curren t literatur e bu t probabl y consist s o

f man y o f the sam e item s consume dby sympatri c gob y species , includin g small crustaceans , mollusks , larva l fishes, an

dfish an dinvertebrat

e eggs . Ba y gob y ar e though t t o b e a n importan

t foo dite mi n the die t o f avariet y o f vertebrate and invertebrat e predators . Their

abundance , smal

l size , an dlon g planktoni c lif

e mak e ba y gob y larva e a n importan

t lin k i n the foodwe

b o f bay/estuarin e system s (Wang , 1986) . Thei r abundanc e a s juvenile s an

dadult s suggest s tha

t the y remai n a n important

forag e specie s throughout

all lif e stages . Th e Pacifi c staghor n sculpin Leptocottus armatus andCaliforni a halibut Paralichthys californicus ar e among th e man

y fish predator s o f

adul t ba y gob y (Brothers , 1975) . I t i s als o assumedtha

t man y o f th e elasmobranch specie s (shark s andrays ) tha t inhabi t estuarin e system s pre

y o n ba y gobie s (Grossman , 1979) . A predator y opisthobranc h specie s Navanax intermis i s als o adocumente dpredator (Paine , 1963) . Wadin g and"prob e feeding " bird s ar e though t t o regularly prey o

n ba y gobie s livin g o

n intertida l mudflat s (Reeder , 1951) . Bir dspecie s lik

e marble dgodwit s Limosafedoa an dwillet s Catoptrophorus semipalmatus ar e abundan t o n expose dtida

l flats an dprobably consum

e agrea t numbe r o f ba y goby . Tem s Sterna spp . ar e als o though

t t o b e among the avia

n predator s ofth e ba

y gob y (Grossman , 1979) . Du e t o their smal l size , ba y gob y ar e not harveste dcommercially fo r huma n consumptio n o r

targete d b y recreationa

l angler s (Wang , 1986) . Ther e i s no mention i

n current literature o

f thei r harves t o r us e a s bait , although they woul dprobably b e a n effective bait

fo r man y species . E9-053. 9 4-3 7 MLP P 316(b ) Resource Assessmen t 4-28-200 0P. 5 4. 0 Entrainmen t an d Source Wate r Results 

### 4.4.1 Bay

goby results (30.4 percent) Ba y gob y comprise d30. 4 percen t o f th e tota l number s o f

larva l fishe s collecte d i n entrainmen t survey s a t th e ne w C C unit s intak e (Figur e 4-1) . The y wer e collecte d i n al l entrainmen t survey s fro mMarc h 2,199 9 throug h Februar y 24 , 200 0 fro mi n front o f th e intak e o f

th e C C unit s (Figur e 4-9) . Concentration s wer e typicall y belo w 200/1,00 0 m 3 fo r fro mMarc h 199 9 throug h mid-Octobe r

1999 . Peak

concentratio n (2,668/1,00 0 m 3 ) occurre d o n Novembe r 18 , 199 9 an d th e lowes t concentratio n (22/1,00 0 m 3 ) occurre d o n Ma y 6 , 1999 . Fro mNovembe r 22 , 199 9 throug h Februar y 24 , 2000 , concentration s range d fro malo w o f 152/1,00 0 m 3 t o ahig h o f 906/1,00 0 m 3 (Figur e 4-9) . Th e die l distribution s wer e plotte dfo r concentration s o f

bay gob y collecte d i n front o f th e ne w combined-cycl e unit s intak e fromJun e 199 9 throug h Februar y 200 0 (Figur e 4-10) . W e analyze d onl y th e entrainmen t

survey s tha

t coincide d wit

h th e sourc e wate r

surveys . Ba y gobie s wer e typicall y collecte d( 8 ou t of 9 surveys ) in highes t

concentration s durin g th e nighttim e betwee n 180 0 an d030 0 hour s PST . I n February 200 0 th e pea

k die l concentratio n occurre d a t daw n a t 062 7 hours . Ba y Gob y Entrainmen t Mea n Concentratio n



## • ••••I-l , •••l.l.lllll l 

# lllillhl l

• ' - --"":s8-3"°?""Sv"? 8ls ***: s,Lj ''* , " ? 2!!?58 " O - J * s a s —M O - J 8 8 s a Figur e 4-9 . Mea

n surve y concentration s (#/1,00 0 m) o f larva l ba y goby a t th e Mos s Landin g Powe

r Plant ne w combined-cycl e unit s intake : Marc h 199 9 through Februar

y 2000 .

E9-053. 9 4-3 8 MLP P 316(b ) Resource Assessmen t 4-28-200 0P. 6

4. 0 Entrainmen t an d Source Wate r Results

Ba y Gob y Larva l Entrainmen t Die l Mea n Concentratio n

| 6.00 0 8 c 3 3 .~ ^

1 . • _ R 

## I n • » l 

# 1 1 1 

# If. .

_• • n I I



## _

__ • B ? a « y tt Au g 1 2 a$ 3 s ' Se p 1 6 ; : 3

s a » 5 * a s - De c 2 9 8:"*'aas; -

Ja n 2 0 Fe b 24 Note : thes e entrainmen t

survey s wer e conducte d coincidentall y wit h sourc e wate r

surveys . Figur e 4-10 . Concentration s (#/l,00 0 m 3 ) o f larva l ba y gob y a t the ne w combined-cycl e unit s intak e separatedb

y sample collectio n tim

e (PST) : June 1999 throug

h Februar y 2000 . Ba y gob y comprise d5. 0 percen t ofth e total fishe s collecte d i n th e Elkhor n Sloug h area , 30. 5 percen t

i n th e Mos s Landin g Harbo r area , an d 4. 1 percen t

i n th e Ocea n are afro mJun e 199 9 throug h Februar y 200 0 (Figur e 4-4) . Bay gob y wer e collecte d in al l survey s (Figur e 4-11) . The y wer e als o collecte da

t al l station s i n November . Th e highes t concentration s occurre d a t hig h tide s i n September , October , Novembe r 1999 , an d Januar y 2000 . Generall y peak concentration s occurre ddurin g hig h tide s excep t i n Augus t

an d December . Th e highes t concentratio n (509/1,00 0 m 3 ) occurre da t hig h tid e i n Octobe r

a t th e Harbo r

Bridg e station .

E9-053. 9 4-3 9 MLP P 316(b ) Resource Assessmen t 4-28-200 04. 0 Entrainmen t an d Sourc e Wate r Result s

Ba y Gob y Sourc e Wate r Mea n Concentratio n P. 7

E 10 0 § 

## i c s • Hig h

• Lo w 

# 1

I oo o OO O OO O !

© i i . — ,— .

°M§8 « Ju n 1 6 Au g 1 2 Se p 1 6 0 iiSS5 t , MSS5 0 MSS*5°8H84 , , M S S Oc t 1 4 No

v1 8 De c 2 9 Ja n 2 0 Fe b 2 4

. Key— KP: Kirb y Park ; D : Dairies ; HB : Harbo r Bridge ; HM : Harbo r

Mouth ; ON : Ocea n North ; OS : Ocean Sout h <2 > Station s no t

include di n stud y desig n unti l September . © Sample s voide ddu e t o imprope r preservation . Figur e 4-11 . Sourc e wate

r concentration s (#/l,00 0 m 3 ) o f larva l ba y gob y a t si x station s nea

r Mos s Landin g Powe

r Plant : June 199 9 through Februar y 2000 . Sub-sample s o f

ba y gob y larva e collecte d fro mth e sourc e wate r survey s an d th e ne w combined

cycl e intak e survey s that

corresponde d t o sourc e wate r surveys (referre d t o a s paire d surveys ) wer e measured . Th e first 5 0 specimen s pe r

sampl e wer e measured . Th e length frequenc y distributio n o f

bay gob y larva e varie d amon g sourc e wate r samplin g locations . Th e larges t number s o f

smal l larva e wer e collecte d fro msamplin g station s locate d i n th e harbor , a s show n i n Figur e 4-12 . Althoug h ou r sampl e siz e o f

length-frequenc y varie d with th e numbe r o f larva e amon g sourc e wate r

samplin g stations , th e shorte r ba y gob y larva e appea r

t o b e missin g fro m both o f th e Elkhor n Sloug h samplin g sites . Very few ba y gob y larva e wer e collecte d in th e uppe r Elkhor n Sloug h (Kirb y Park) . Thi s findin g alon g wit h apatter n o f

increasin g averag e larva l siz e an dconcentratio n at

th e Dairie s Statio n suggest s tha t th e sourc e o f

ba y gob y larva e i s somewher e i n th e directio n o f

th e harbo r

an dMontere y Bay . Th e appearanc e o f large r (possibl y olde r

stage ) larva e collecte di n th e mid-sloug h sample s (Dairie s Station ) i s consisten t with atranspor t

o f larva e fro maharbor/ba y sourc e u p th e slough . Thi s patter n o f shorte r t o longe r larva l length fro mth e Montere y Ba y t o uppe r sloug h woul d poin t

t o th e Mos s Landin g Harbo r an d Montere y Ba y a s alarva l source . Th e stron g patter n o f decreasin g concentratio n o f ba y gob y larva e fro m th e harbor-ba y t o th e uppe r sloug h als o point s t o th e harbor-ba y a s aprimar y sourc e o f ba y gob y larvae . Thi s conclusio n i s consisten t wit h ou r knowledg e ofth e species ' preferre d spawnin g habitat . E9-053. 9 4-4 0 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P. 8

4. 0 Entrainmen t an d Sourc e Wate r Result s

Ba y Gob y Vs Statio n

Figur e 4-12 . Lengt

h frequency o

f al l larva l ba y gob y Lepidogobius lepidus length s measured (n=l,lll* ) b y sourc e wate

r an dintak e sampling location s (June 1999 throug h Januar y 2000) . *C C Unit s intake : N = 862 ; sourc

e wate r survey: N = 24

9 Th e lengt h frequenc y o f

al l ba y gob y larva e fromth e paire d surveys i s plotte d i n Figur e 4-1 3 alon g with th e length frequenc y o f sourc e wate r

specimen s collecte d a

t hig h an d lo w tid e stages . Th e figur e show s tha t

mor e individual s wer e collecte d a t hig h tide , particularl y i n th e 3. 0 t o 3. 1 siz e classes . Hig h tid e wate r qualit y condition s o r

current s appear

t o favo r hatchin g an d distributio n o f

ba y gob y larvae . Th e lengt h o f specimen s range d fro m3 t o 4. 2 mm ; th e majority o f individual s wer e betwee n 3. 3 an d3. 6 mm . Al l o f th e ba y gob y length s measure d fro mboth entrainmen t

an dsourc e wate r

sub-sample s ar e plotte db y surve y i n th e Figur e 4-1 4 scattergram . Inspectin g th e scattergra mfo r period s o f

larg e number s o f

smalle r individual s followe d b y period s o f

fewe r an dlarge r

individual s t o indicat e ahatchin g event , i t i s possibl e tha t

acohort o f ba y gobie s hatche di n Jul y an dNovembe r 1999 . Howeve r

th e trend s ar e slight , an d th e increas e i n average length betwee n survey s appear s t o b e les s tha n expecte d basedo n th e growth o f individual s i n asingl e cohort . I t i s mor e likel y tha t

hatchin g occurre d severa l time s durin g th e summe r an dfal l months , an dth e residua l cohort o f eac h hatchin g puls e blende d i n with ne w peak s o f hatchin g larvae .

E9-053. 9 4-4 1 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P. 9

4 0 3 5 3 0 2 5

^ 2 0 o E 5 1 5 1 0 5 - - 4. 0 Entrainmen t an d Sourc e Wate r Result s

Ba y Gob y Lengt h Frequenc y v s Tid e

• Lo w Tid e D Hig h Tid e 

# ffl I J L 3 3. 1 32 3. 3 -3. 4 3. 5 3. 6 3. 7 3. 8 3. 9 4 4. 1 4. 2 4. 3 4. 4 4. 5 4. 6 4. 7 4. 8 4. 9 5 Lengt h (mm ) Figur e 4-13 . Lengt

h frequency of

all larva l ba y goby Lepidogobius lepidus measure d (n=l, l 11* ) by hig h an d low tide stag e (June 199 9 throug h Januar y 2000) . *CC Units intake : N = 862 ; sourc e wate r survey : N = 24 9

E9-053. 9 4-4 2 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.1 0

4.0 0 3.5 0 3.0 0 2.5 0 2.0 0

1.0 0 0.5 0 0.0 0 05/20/9 9 4. 0 Entrainmen t an d Sourc e Wate r Result s

Ba y Gob y Lengt h b

y Dat e 

# 1 K 

# 1 j \ 

# 1

• *

• <

< 

# } • *

> t i 1 

# I * • •

i

i • »

07/09/9 9 08/28/9 9 10/17/9 9 Dat e 01/25/0 0 03/15/0 0 Figur e 4-14 . Scattergra

mplo t o f all larva l ba y goby Lepidogobius lepidus length s measured (n=l, l 11* ) b y sourc e wate

r surve y dat e (June 199 9 through Januar y 2000) . *C C Unit s intake : N = 862 ; sourc e wate r survey : N = 24 9 Ba y gob y wer e no t

identifie di n th e PG& E (1983 ) entrainmen t studies . It

i s likel y tha t

the y wer e collecte dan dtha t

the y wer e include d i n th e genera l Famil y Gobiida e dat aanalysi s discusse d i n Sectio n 4.3 .

E9-053. 9 4-4 3 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.1 1

4. 0 Entrainmen t an d Source Wate r Results 

## 4. 5 Blackeye Goby

Coryphopterus

nicholsi Photographer : Da n Duga n Range: Fro mPoin t

Rompiente , Baj aCaliforni at o Quee n Charlott e Islands , Britis h Columbia . Life History: Size : t o 15 0 m m( 6 in.) ; Ag e at

maturity : tw o years , protogynou s hermaphrodite ; Fecundity : 3,30 0

_t o 4,80 0 eggs ; lifespan : five years . Habitat: Rock y reef

s near sand-roc k

interface . Fishery: None .

Distributio n Ma p fo r

Blackey e Gob y 

### Th e blackey e goby Coryphopterus nicholsi occur s commonl y aroundnearshor

e reef s fro m Quee n Charlott e Islands , Britis h Columbi at o Point Rompient e in Baj aCaliforni a(Mille

r an d Lea , 1972) . They ar

e amarine specie s bu

t will occasionally enter

bay s andestuarie s (Wang , 1986) . Blackey e gob

y typically inhabi t

benthi c substrate s nea

r th e sand-rock

interface . They liv e i n crevice s an

dburrow s within small territorie s tha t they defen

daggressivel y (Love , 1996) . Blackey e goby ar

e know n t o occu r fro mthe intertida

l zone dow

n to depth s o

f 13 7 m(45 0 ft. ) (Love , 1996) . Th e specie s i s reporte dt o b e largely diurna

l (Love , 1996) . Fossi l blackey e gob y otolith s hav e bee

n identifiedfro

mPliocen e deposit s i

n Californi atha

t ar e estimate dhav e bee

n formedbetwee

n 8 an d1 2 millio n year s ag o (Eber t andTurner , 1962) . Har

t (1973 ) reporte d tha

t "blackeye goby larva

e hav e th e abilit

y t o surviv e exposur

e to lo w salinities . E9-053. 9 4-4 4 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.1 2 

# 1

H 

# 1 1 1 H 

# I 

# I 1 1 1 4. 0 Entrainmen t an d Sourc e Wate rResult s



# 1 Th

e blackey e gob y i s a

n elongate , medium-size dgob y tha t ca n b e distinguishe dfro

mother member s o

f th e famil y b y their larg e scales , ligh

t coloration , an

daflesh y ridge tha

t extend s dorsally fro

mt o jus t behindth e eye s t o the insertio n o

f the firs t dorsa l fi n (Eber t andTurner , 1962) . Blackey e gob y reach amaximu msiz e o f abou t 15 0 m m( 6 in. ) andhav e alif

e spa n o f a s muc h a s 5 year s (Love , 1996) . Wit h the exceptio n o

f portion s o f thei r head , thei r

bod y i s covere d wit

h large , cycloi dscale s (Hart , 1973) . Blackey e goby ar e pal e ta n to orange-oliv e i

n coloratio n wit

h som e brownis h an

dgree n specklin g (Mille

r an dLea , 1972 ; Hart , 1973) . A small iridescen t blu e spot i s presen t belo w eac h o f the larg e blac

k eye s an dthe dista l margin o f their first dorsa l fin i s tippe dwit

h black (Eber t an dTurner , 1962 ; Miller

an dLea , 1972 ; Hart , 1973 ; Love , 1996) . Blackey e gob y hav e amoderate-sized , termina l mout h tha t i s directe dforwar

d (Hart , 1973) . Th e joine dpelvi c fin s o f male s becom

e darke r i n color durin g breedin g season (Eber t an dTurner , 1962 ; Love , 1996) . Th e specie s i s hermaphroditi c (protogynous ) s o all blackey e goby star

t lif e a s female s (Wiley , 1973 ; Love , 1996) . They become reproductively matur e within 2 year s an

da t atota l lengt h (TL) o f 3 8 t o 5 1 m m(1. 5 to 2 in. ) (Love , 1996) . Femal e blackey e goby transfor minto male s a

t around64 t

o 7 6 m m(TL ) (2. 5 t

o 3 in.) . Male s ca n be recognize dby th

e presenc e o

f aprotrudin g urogenita

l papill a(Wang , 1986 ; Love , 1996) . Femal e blackey e gob y ar

e oviparou s an

dbasedo n examination s o

f ov aby Wiley (1973 ) ar

e abl e to spaw n mor e tha n onc e durin g aseason (Wang , 1986) . Th e spawnin g seaso n o f blackey e gobie s extend s fro

mFebruar y through Octobe

r (Eber t an dTurner , 1962 ; Wiley , 1973 ; Love , 1996) . Pea

k spawnin g activit

y occur s i n the late sprin g an

dearl y summe

r (Love , 1996) . Male s prepar e anes t by clearin g (scraping ) a

n are ao n the underside o

f ledge s o r underneat h rock s fo r eg g attachmen

t (Love , 1996) . Female s deposit betwee n 3,30 0 and4,80 0 elongate/oblon g egg s in the nes t (Wiley , 1973 ; Love , 1996) . Eber t an dTurne r (1962 ) calculate da

n averag e nes t

siz e o f 1,70 0 eggs . Egg s ar

e demersa l an dadhesiv e a

t th e poin t o f attachmen

t (Eber t andTurner , 1962 ; Wiley , 1973) . Nests , formedb y asingl e laye r o f eggf. , ar e generally circula

r i n shap e and averag e abou

t 10 0 m m( 4 in. ) i n diamete r (Eber t an dTurner , 1962) . Male s guar dth e nes t and ten dth e egg s until the

y hatch (Love , 1996) . N o information was availabl e concernin g incubatio n time . Newly hatche dlarvae ar e planktoni c an

dabou t 3 m m(0.1 2 in. ) i

n lengt h (Eber t and Turner , 1962) . Larva

e ca n b e carrie dgrea

t distance s by current s andwindaction . Juvenile s have bee n foun di n surfac e water s fa

r offshor e a s wel l a s i n th e stomach s o

f albacore (Eber

t and Turner , 1962) . Th e duratio n ofth e planktoni c larva l phas e i s approximately 7 5 day s (Steele , 1997) . Juvenile s begin settlin g ou t o f th e wate r colum n a t alengt h (TL ) o f 2 1 t o 2 8 m

m(0.8 3 t o 1. 1 in. ) an dsee k out rock y substrate s t

o commenc e their

demersa l lif e phas e (Wang , 1986) . No species-specifi c larva

l survivorshi

p estimate s wer

e availabl e fo

r blackey e goby . However , Brother s (1975 ) calculate dlarva l mortalit y ove r two-months , post-hatchin g fo r thre e sympatri c gobiid s (arro w goby , cheekspo t goby , an dshadow goby ) fro

mMissio n Bay , California . Thes e estimate s wer

e use dt o approximat

e ba y gob y mortalit y fo r earl y lif e stage s a s well a s post E9-053. 9 4-4 5 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.1 3



## I I 

# 1 1

H I E 

# 1 1 1 1 1 1 1 1 1 4. 0 Entrainmen t an d Sourc e Wate rResult s



### settlemen t juvenil e andadult

stages . Lac

k o f species-specifi c fecundit

y datapreclude d estimatio n o

f FH fo r thi s species , bu

t substitutin g survivorship fro mthes e closel y relate dspecie s fo r larval , juvenile , andadult

stage s allowedu s to project futur e losse s o f equivalent

adults . Blackey e gob y consum

e avariet y o f smal l organism s andlarva

l forms . Th e diet

o f juvenile s include s crustacean s suc

h a s copepod s an

damphipod s an

dtheir nauplii , a s well a s mollus k an d echinoder mlarvae , an

dbryozoan s (Wang , 1986) . Th e die t o f adult blackey e gob y consist s mostly o f small crustacean s (copepod s an damphipods ) an

dmollusk s suc

h a s limpet s an

d snail s (Love , 1996) . Durin g their planktoni c stag e larva

l blackey e gob y ar

e probably consume d by a variet y o f species . Juvenile s an

dadult s develop predator

avoidanc e behavio r

but stil l fal l prey t o numerou s fis

h an dbir dspecies . Divin g bird s suc h as pelagic , Brandt's , an

ddouble-creste d cormorant s ar

e among th

e reporte davia

n predator s o

f blackey e goby (Love , 1996) . Blackey e gob y ar e no t targete dby commercia

l o r recreationa

l fishermen an

dar e probably rarely , if

ever , taken . 

### 4.5.1 BOsickeye

goby results (3.0 percent) Blackey e gob

y comprise d3. 0 percen

t o f the tota l number s o

f larva l fishe s collecte di

n entrainmen

t survey s a t the ne w CC unit s intak

e (Figur e 4-1) . The

y wer e collecte di

n al l entrainmen

t survey s fro

mMarc h 2 , 199 9 throug

h Decembe

r 9 , 199 9 fro

mi n fron t ofth e intak

e o f th e ne w C C unit s (Figur

e 4-15) . They wer

e collecte dagain in low concentration s (belo w 35/1,00 0 m3 

### ) i

n th e Decembe

r 21 , Decembe

r 29,199 9 an

dJanuar y 13 , Februar

y 3 , Februar

y 10 , andFebruar

y 24,200 0 surveys . Pea

k concentratio n (281/1,00 0 m3 

### ) occurre do n Novembe

r 11 , 199 9 and the lowes t

concentratio n (1/1,00 0 m 3 

### ) occurre do

n March 2,1999 . Concentration s wer e typically belo w 50/1,00 0 m 3 

### fo r most ofth e tim e perio dsampled . Th e die l distribution s wer

e plotte dfo

r concentration s o

f blackey e gob y collecte di

n fron t o f th e ne w combined-cycl e unit s intak e fro mJun e 199 9 through Februar y 200 0 (Figur

e 4-16) . W

e analyze d onl

y th e entrainmen

t survey s tha

t coincide dwit

h the sourc e wate

r surveys . The

y wer e no t collecte d i

n the Januar

y 200 0 entrainmen

t surve y tha t coincide dwit

h th e sourc e wate

r survey . Blackey e goby wer e typically collecte di

n highes t concentration s durin g th e nighttime between 220 0 an

d230 0 hour s PS T except

i n Octobe r whe n the highes t

concentratio n occurre d afte r sunset a t 182 9 PS T hours .

E9-053. 9 4-4 6 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.1 4

4. 0 Entrainmen t an d Source Wate r Results Blackey e Gob y Entrainmen

t Mean Concentratio n 30 0

25 0

20 0

15 0

g 10 0 o 2

0 J 

## ••••III - 

# Jil l • • I . 

### X f I f i •

? ? * - 5 | i i i r i i i t t i i f | s s f f f i ? - ? i ? i f i i i . i

i t t ? s i s as m a- i s s = s K 5 8 j • i * i j - • • • - s i • g - _ s B * i s j , Figur e 4-15 . Mean surve y concentration s (#/1,00 0 m) o f larval blackey e gob y a

t th e Mos s Landin g Powe r Plan t ne w combined-cycl e unit s intake : Marc h 199 9 throug h Februar y 2000 .

E9-053. 9 4-4 7 MLP P 316(b ) Resource Assessmen t 4-28-200 0' P.1 5 

### " 1

4. 0 Entrainmen t an d Source Wate r Results Blackey e Gob y Larva l Entrainmen

t Die l Mean Concentratio n 700- i

^50 0 Eentratlon{3IMeanCone

0 TM 

### 1 

# . 1

. I i B- S • . ' • 1 • 

# I I • En l m •

m a1 s : i x X 8 » ' 2 Au g 1 2 Se p 1 6 ; ; : B 8 s 5 a Oc t 1 4 Ja n 2 0 Fe b 2 4 Note : thes e entrainmen

t survey s wer

e conductedcoincidentall

y wit h sourc e wate

r surveys . 

### Figur e 4-16 . Concentrations (#/l,00 0 m 3

### ) o f larva l blackey e gob y a t th e ne w combined-cycl

e unit s intak e separate db y sampl e collectio n tim e (PST) : Jun

e 199 9 throug h Februar y 2000 . Blackey e gob y comprise d1. 6 percen t ofth e tota

l fishe s collecte di

n th e Elkhor

n Slough area , 2. 9 percen t i n th e Mos s Landin g Harbo r area , an dles s tha n 1 percen

t i n th e Ocea

n are afro m Jun e 199 9 throug

h Februar y 200 0 (Figur

e 4-4) . Blackey e gob y wer e collecte di

n all month s except Decembe r 199 9 an dJanuar y 200 0 (Figur

e 4-17) . They wer

e onl y collecte da

t lo w tide s excep t a t Kirb y Par k i n Jun e an dNovembe

r 199 9 an dth e Dairie s an

dHarbo r Mout h i n Februar y 2000 . However , th e pea

k concentratio n (280/1,00 0 m 3 

### ) occurre da t hig h tid e i

n Jun e a t Kirb y Park . Blackey e gob y wer

e no t collecte da

t th e Ocea n station s except

a t the Ocea n Nort h statio n durin g alo w tide in October . Blackey e gob y wer

e not identifie di

n th e PG&E (1983 ) entrainmen t studies . It

i s likel y tha

t they wer e collecte dandtha

t they wer e include di

n th e genera

l Family Gobiida

e dataanalysi s discusse di n Section 4.3 .

E9-053. 9 4-4 8 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.1 6

4. 0 Entrainmen t an d Source Wate r Results 

## 4. 7 Whit e Croake r Source : CDF G



### Genyonemus

lineatus Range: Fro mTodo s Santo s Bay , Baj aCaliforni anort h t o Barkle y Sound , Vancouve r Island , Britis h Columbia . Life History: Size : u p t o 380 m m(1 5 in. ) an d0. 5 k

g ( 1 lb) ; Ag e a

t maturity : on e t o four

years ; Fecundity : spawn s 1 8 t o 2 4 time s aseason , 80 0 t o 37,00 0 eggs ; Lif e span : twelv e t o fifteen years . Habitat: Near

shor e an doffshor e water s t o 10 0 m (32 8 ft ) i n depth . Fishery: Recreational , smal l commercia l market .

Distribution Ma

p fo r Whit e Croake r Th e whit e croaker , als o calle ddrum , belong s t o th e Famil y Sciaenida e (Orde r Perciformes ) whic h contain s ove r

21 0 species . Whit e croake r ar e foun d fro msouther n Baj aCaliforni at o Vancouve r

Island , Britis h Columbia . The y ar e mos t abundan t fro msouther n Californi a northwar dt o abou t

Monterey ; the y ar e uncommo n north o f San Francisc o (Love , 1996) . The y ar e presen t

i n th e Sacramento-Sa n Joaqui n Estuary , Tomale s Bay , an d th e Mos s Landin g Harbor/Elkhor n Sloug h area . In North America , ther e ar e abou t 3 4 specie s o f

croaker , man y o f the mimportan t

a s sport an dcommercia l fishe s (Moyl e an d Cech , 1988) . Th e whit e croake r ha s bee n give n man y names ; i n centra l Californi aan d in mos t fish markets , "kingfish " i s mos t ofte n used . Whit e croake r

ar e bottom-dwellin g fishe s foun d schoolin g an d feedin g alon g warm , shallow , nearshor e coasts . Whit e croake r ar e usuall y foun d i n loos e school s ove r san d o r mu d bottom s o f bay s an destuarie s an di n area s les s than 3 0 m(9 8 ft ) dee p jus t

outsid e th e surf

zon e (Streamnet , 1999) . The y may also , however , inhabi t off-shor e water s u p t o 10 0 m(32 8 ft ) dee p (Frey , 1971) . E9-053. 9 4-5 6 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.1 7 

# 1 1 1

I I I B 

# 1 4. 0 Entrainmen t an d Source Wate r Results

Thes e fish see mt o mov e inshor e durin g summe r month s an d offshor e i n winter . Whit e croaker , silve r i n color , can reac h 38 0 mm(1 5 in. ) i n length an d can weig h ove r 0. 5 k g ( 1 lb ) (Streamnet , 1999) . Thes e fish reac h maturit y i n on e t o four year s an d ma y liv e fro mtwelv e t o fiftee n year s (Frey , 1971) . Althoug h som e spawnin g take s plac e throughou t th e year , mos t

occur s betwee n Novembe r an d Ma y (Skogsberg , 1939 ) with th e heavies t concentratio n durin g th e earl y sprin g months . Adult s spaw n i n both near-shor e shallo w water s an d th e ope n water s o f bay s an d estuaries . A larg e spawnin g cente r

i s locate dnorth an d sout h ofth e Palo s Verde s Peninsula , fro mRedond o Beac h t o Lagun aBeach , an dasmalle r cente r i s foun d north o f

Ventura(Lov e e t

al. , 1984) . Female s la y fro m80 0 t o 37,00 0 eggs , an dar e abl e t o spaw n 1 8 t o 2 4 time s aseaso n (Lov e e t al. , 1984) . Th e fertilize degg s ar e pelagi c an dmos t drif t int o th e shallo w san d an d grave l botto mregion s ofth e bay s an destuaries . Th e spherica l egg s hatc h i n abou t on e week , wit

h th e newl y hatche d larva e averagin g abou t 1. 6 mm(0.0 6 in.) (Watson , 1982) . Th e youn g larva e ar e pelagi c an d post-flexio n larva e settl e ou t t o th e san dan dgrave l botto msubstrat e a s the y develo p (Lov e e t al. , 1984) . Ther e ar e n o species-specifi c estimate s o f survivorshi p i n th e literatur e an d therefor e w e assume d a9 9 percen t larva l mortalit y throug h settlement . Length frequenc y analysi s o f whit e croake r

larva e a t th e Diabl o Canyo n Powe r

Plan t i n yielde d mortalit y rate s o f approximatel y 9 9 percen t (Tenera , 2000) . Murdoc h e t

al . (1989 ) estimate s adail y larva l growth rat e o f 0.2 0 m mpe r

day . Th e shallow s o f

bay s an destuarie s ar e use d a s nurser y ground s for th e whit e croaker , bu t

larva e ar e foun di n ope n wate r

a s wel l (Wang , 1986) . Whil e afe w larva e hav e bee n take n a s fa r a s 15 0 mile s offshore , mos t

larva e resid e withi n 2 0 mile s o f th e coas t (Love , 1996) . Earl y juvenile s remai n i n th e bay s an d estuaries ; a s the y mature , th e juvenile s graduall y migrat e t o deepe r ocea n waters , usuall y i n th e summe r an d fal l (Wang , 1986) . Juvenile s ar e approximatel y 1. 3 t o 1 3 c mT L (Emmett e t al. , 1991) . Bot

h juvenile s an d adult s favo r cloud y water . Th e whit e croaker , althoug h no t o f prim e importance , ha s commercia l valu e a s bai t an d a s afoo d fish. Commercia l landin g informatio n for whit e croake r

in th e Montere y an d Mos s Landin g are a i s show n i n Figur e 4-22 aan db . I n additio n t o man , whit e croake r ar e preye d upo n b y tuna , se a bass , dolphin , halibut , an dse alions . Whit e croake r fee d o n jus t

abou t anything , includin g crabs , shrimps , mollusks , an ddetritus . Sinc e i t i s omnivorou s an d feed s i n nearshor e waters , th e whit e croake r i s susceptibl e t o pollutant s accumulatin g i n it s tissues . Th e whit e croake r fishery ha s bee n subjec t

t o occasiona l closure s du e t o health threat s t o humans .

E9-053. 9 4-5 7 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.1 8

4. 0 Entrainmen t an d Sourc e Wate r Result s (a ) 1.2 -, 

### s 10 

### - c 2 0. 8 - ,§ . 0. 6 - c 0. 4 - 3 o a 0. 2 - 0. 0 - C O o > 

### Whit e Croake r Landing s

Q 3 0 ) O »* • <V Ci Q D Q

D O ) 0 5 0 5 0 5 0 5 O ) 0 5 0 5 0 > 0 5 

### 198 7 t o 199 8 1 Stat e Tota l •jMontere y Are a • Mos s Landin g

v < o C O ^ O ) 0 5 C O 0 > O ) O ) O ) O ) 5 3 O S O ) (b) 

### Whit e Croake r Landin g Value s 198 7 t o 199 8 pMontere y Are a

• Mos s Landin g

Source: CDFG Landing Tables Figur e 4-22 . (a

) Whit e croake r Californi astate-wide , Montere y area , an d Mos s Landin g Harbor

landing s (1,000,00 0 lbs ) an

d(b ) White croake

r Californi astate-wide , Montere y are aan d Mos s Landin g Harbor landing s value s (dollars) : 198 7 t o 1998 . 

### 4.7.1 White

Croaker

Results (2.1 percent) Whit e croake r

comprise d2. 1 percen t

o f th e tota l number s o f

larva l fishes collecte d i n entrainmen t

surveys at

th e ne w C C unit s intak e (Figur e 4-1) . The y wer e collecte d i n fou r entrainmen t

survey s i n Marc h 199 9 an d th e first surve y i n Apri l 199 9 (Figur e 4-23) . A hig h concentratio n (197/1,00 0 m 3 ) occurre d o n Marc h 8 , 1999 . Whit e croake r larva e wer e collecte d o n Jun e 24 , 199 9 i n lo w concentration s (2/1,00 0 m 3 ) . Beginnin g in Novembe r 199 9 the y wer e

E9-053. 9 4-5 8 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.1 9

4. 0 Entrainmen t an d Source Wate r Results 

### collecte d i n eac h weekl y surve y excep t o n Januar y 21 , 2000 . The highes t

pea k concentratio n (226/1,00 0 m 3 

### ) occurre don Decembe r 21,1999 . The diel distribution s wer

e plotte dfo

r concentration s o

f larva l whit e croake r collecte di

n fron t o f the ne w combined-cycl e unit s intak e fro mJun e 199 9 through Februar y 200 0 (Figure 4-24) . W

e analyzed onl

y th e entrainmen

t survey s tha

t coincide dwit

h th e sourc e wate

r surveys . Durin g Jun e through Octobe

r 199 9 an ddurin g Januar

y 200 0 n o whit

e croaker larvae wer

e collecte d i

n entrainmen

t survey s tha

t coincide dwit

h sourc e wate

r surveys . Whit e Croake r Entrainmen t Mea n Concentratio n

8 g 10 0

5 0 

# J

J L 

# I

_ _ _

### .Il a 

# IB - 

# I I | |



# I I

= N i. s a v. - m Z g = s 8 - * s » 3 j s 8 "''-'- " = "•-'••'•" ' -""*•*' * **' • 8 8 5 S 8 

### Figur e 4-23 . Mea

n surve y concentrations (#/1,00

0 m ) o f larva l whit e croake r a t th e Mos s Landin

g Powe r Plan t ne w combined-cycl

e unit s intake : Marc

h 199 9 throug h Februar y 2000 . I n Novembe

r 199 9 larva

l whit e croaker wer e collecte di

n highes t concentration s befor

e daw n (063 6 PST) . I

n Decembe

r 199 9 an dFebruar y 200 0 larva

l whit e croaker wer e collecte di

n nearly equa l pea k concentration s durin g nighttim e anddaytime .

E9-053. 9 4-5 9 MLP P 316(b ) Resource Assessmen t 4-28-200 04. 0 Entrainmen t an d Sourc e Wate r Result s

Whit e Croaker Larva l Entrainmen t Die l Mea

n Concentratio n

5 8 0 

### I tl C | j 6 0 S c 3 s ] 

# 1



# 1 l l 1 1 1

« ; = B - Ju l 1 2 ; 3 ;

Au g 1 2 5 s : 3 ? t 8 S Se p 1 6 Note : Thes e entrainmen t survey s wer e conducte dcoincidentall y wit h sourc e wate r

surveys . Figur e 4-24 . Concentration s (#/1,00 0 m 3 ) o f larva l whit e croake r a t the ne w combined-cycl e unit s intak e separatedb

y sample collectio n tim

e (PST) : Jun e 1999 throug

h Februar y 2000 . Whit e croake r

comprise dles s tha

n 1 percen t

o f th e larval fish tax acollecte d i n th e Elkhor n Sloug h area , 0. 9 percen t

i n th e Mos s Landin g Harbo r area , an d 4. 4 percen t

i n th e Ocea n area . Whit e croake r

larva e wer e collecte donl y durin g th e October , November , Decembe r 1999 , an d Februar y 200 0 survey s (Figur e 4-25) . The y wer e collecte d fro mth e Ocea n South Statio n i n Octobe r an dNovember , fro mth e Dairie s Statio n i n November , an d fro mth e Harbo r Bridg e Statio n i n December . Whit e croake r larva e wer e no t

collecte d at

an y station s i n th e Januar y 200 0 sourc e wate r

survey . The y wer e collecte d at al l station s excep t

Kirb y Par k

i n Februar y 2000 . Th e peak

hig h an dlo w tid e concentration s (155/1,00 0 m 3 an d 116/1,00 0 m 3 , respectively ) occurre da

t Kirb y Park

i n Februar y 2000 . Whit e croake r

larva e wer e entraine dfro mAugus t 197 9 t o Marc h 198 0 durin g th e first entrainmen t

stud y (PG&E , 1983) . Th e peak concentratio n (400/1,00 0 m 3 ) occurre d a t th e Unit s 1 throug h 5 intak e i n Novembe r an d Decembe r

197 9 (PG&E , 1983) .

E9-053. 9 4-6 0 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0[<T' - P.2 1 

### " 1 4. 0 Entrainmen t an d Source Wate r Results

Whit e Croake r Sourc e Wate r Mea n Concentratio n BHig h • Lo w

O O O O O O O O O j i ! 

# 1

8 Jun1 6 Ju l 1 2 Aug1 2 Se p 1 6 Oc t 1 4 No v 1 6 Dec2 9 Ja n 2 0 Feb2 4 Key— KP: Kirb y Park ; D : Dairies : HB : Harbo r Bridge ; HM : Harbo r

Mouth ; ON : Ocea n North ; OS : Ocea n Sout h O Station s not

include di

n stud y desig n unti l September . © Sample s voide ddu e t o imprope r preservation . Figure 4-25 . Sourc e wate

r concentration s (#/l,00 0 m 3 ) o f larva l whit e croake r a t si x station s nea

r Mos s Landin g Powe

r Plant : June 199 9 throug

h Februar y 2000 .

E9-053. 9 4-6 1 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.2 2

4. 0 Entrainmen t an d Source Wate r Results 

## 4. 8 Blenniidae : Combtoot h blennie s Combtoot h blennie s ar e aprominen t grou p amon g th e fish faun atha t inhabit s inshor e rock y habitat s throughou t

muc h o f th e world . The y ar e member s o f th e Famil y Blenniida e withi n th e Orde r Blennioidei , whic h als o include s th e clinids . Clinid s ar e a n extremel y variabl e grou p o f intertida l fishe s tha t

include s kelpfis h Gibbonsia spp . an d fringehead s Neoclinus spp . Th e Famil y Blenniidae , th e combtooth blennies , contain s aroun d 34 5 specie s i n 5 3 gener a(Nelson , 1994 ; Moser , 1996) . The y deriv e thei r commo n nam e fro mth e arrangemen t o f closel y space d teet h in thei r jaws . Fou r

Blennii dspecie s hav e bee n reporte d t o occu r i n th e CalCOF I stud y area , althoug h one , Ophioblennius steindachneri, onl y range s a s fa r nort h a s Baji aSebastia n Vizcain o i n centra l Baj aCaliforni a(Moser , 1996) . Th e Famil y Bleniida e i s compose do f specie s tha t

var y widel y in genera l appearanc e (Moser , 1996) . Despit e thi s diversit y i n appearanc e th e famil y share s severa l commo n externa l characteristics . Combtooth blennie s ar e al l relativel y smal l fishe s tha t typicall y gro w t o atota l lengt h o f les s than 20 0 mm(7. 9 in.) (Moser , 1996) . Mos t hav e blun t

head s tha t

ar e toppe d wit

h som e arrangement

o f cirri (Moyl e an d Cech , 1988 ; Moser , 1996) . Thei r bodie s ar e generall y elongat e an dwithou t

scales . Dorsa l fins ar e ofte n continuou s an d contai n mor e sof t ray s than spine s (Moyl e an dCech , 1988) . Coloratio n i n th e grou p i s quit e variable , eve n amon g individual s ofth e sam e species-(Stephen s e t al. , 1970) . Blennie s inhabi t

avariety o f

har dsubstrate s i n th e intertida l an d shallo w subtida l zone s o f tropica l an dsubtropica l marin e habitat s throughou t th e world . The y ma y occu r t o depth s o f 2 4 m(8 0 ft) but

ar e mor e frequentl y foun d i n wate r depth s o f les s than 5 m(1 5 ft

) (Love , 1996) . Combtoot h blennie s ar e commo n i n rocky tidepools , reefs , breakwaters , an d o n pie r pilings . The y ar e als o frequentl y observe do n encruste d buoy s an d boa t hulls . With th e exceptio n o f th e semi-pelagi c sabertooth blenn y Aspidontus taeniatus the y ten d t o b e demersa l (Moser , 1996) . Combtooth blennie s ar e omnivore s an d ea t both alga e an d avariet y o f invertebrates , includin g limpets , urchins , an dbryozo a(Love , 1996) . 

### 4.8.1 Hypsoblennius

Spp . Combtooth blennie s ar e represente dalon g th e Californi acoas t b y thre e member s o f

th e genu s Hypsoblennius; th e ba y blenn y Hypsoblennius gentilis, rockpoo l blenn y Hypsoblennius gilberti, an dmusse l blenn y Hypsoblennius jenkinsi. Thes e specie s co-occu r throughou t

muc h o f thei r range . Th e ba y blenn y H. gentilis i s foun d alon g bot h coast s o f

Baj aCaliforni aan d u p th e Californi acoas t

t o a s fa r north a s Montere y Bay , althoug h i t i s absen t fro mth e Cap e Sa

n Luca s are a(Mille r

an dLea , 1972 ; Stephen s e t al. , 1970) . Th e distributio n ofth e rockpoo l blenn y H. gilberti extend s fro mMagdalen aBay , Baj aCaliforni at o Pt . Conception , California(Mille r E9-053. 9 4-6 2 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.2 3 

# 1 1 I

1

1 4. 0 Entrainmen t an d Sourc e Wate rResult s

an d Lea , 1972 ; Stephen s e t al. , 1970) . Th e rang e o f th e musse l blenn y H. jenkinsi extend s onl y a s fa r nort h a s Coa l Oi l Poin t

i n SantaBarbar aCount y bu t occur s south t o Puert aMarquis , Mexic o (Mille r

an dLea , 1972 ; Stephen s e t al. , 1970) . Eac h specie s appear s t o hav e differen t habita t preferences . Th e musse l blenn y H. jenkinsi i s onl y foun d subtidall y an d inhabit s musse l beds , th e burrow s o f

borin g clams , o r

Serpulorbis spp . tube s (Stephen s e t al. , 1970) . The y generall y remai n withi n on e mete r o f thei r chose n refug e (Stephen s e t al. , 1970) . Rockpoo l blenn y H. gilberti typicall y inhabi t cobbl e i n th e intertida l an d shallo w subtida l zon e an dma y regularl y rang e a s fa

r a s 1 5 m(4 9 ft

) withi n thei r

territories . Ba y blenn y H. gentilis are usuall y foun dsubtidall y bu t

appear t o hav e genera l habita t

requirement s an d ma y inhabi t avariet y o f intertida l an dsubtida l area s (Stephen s e t al. , 1970) . Ba y blenn y ar e commonl y foun d i n musse l Mytilis spp . bed s an do n encruste dfloats , buoys , docks , an d eve n foule d boa t hull s (Stephen s e t al. , 1970) . H. gentilis ar e ofte n foun d in bay s an d ar e toleran t o f nearl y estuarin e condition s (Stephen s et

al. , 1970) . The y ar e amon g th e firs t fish specie s t o coloniz e ne w o r disturbe d marin e habitat s suc h a s ne w breakwater s (Stephen s e t al. , 1970 ; Moyl e an d Cech , 1988) . Ther e ar e severa l morphologica l difference s betwee n th e adult s o f thre e sympatri c Hypsoblennius species . Th e hea dshap e i s different , a s i s th e posterio r exten t o f th e latera l lin e (Stephen s e t

al. , 1970) . I

n addition , th e numbe r

o f fin rays , coloration , an d siz e may b e distinguishin g characteristic s amon g adult s (Stephen s e t al. , 1970) . Ba y blenn y ar e th e larges t o f th e thre e Hypsoblennius specie s inhabitin g th e Californi acoast , reachin g asiz e o f 14 7 m m (5. 8 in. ) an dlivin g fo r

at leas t 7 year s (Stephen s e t

al. , 1970 ; Mille r

an d Lea , 1972) . Th e rockpoo l blenn y attain s asiz e o f 14 0 mm(5. 5 in.) an d ma y liv e fo r 8 t o 1 0 year s (Stephen s e t al. , 1970 ; Mille r

an dLea , 1972) . Stephen s e t al . (1970 ) state d tha t

th e rockpoo l blenn y gre w faste r an d attaine dalarge r

siz e than th e ba y blenny , however , Mille r an d Le a(1972 ) list s th e ba y blenn y a s growin g larger . Th e smallest ar e musse l blenn y whic h gro w t o 11 2 m m(4. 4 in.) an d hav e alif e span 3 t o 6 year s (Stephen s e t al. , 1970 ; Mille r

an d Lea , 1972) . Mal e an d femal e growth rate s ar e similar . Femal e rockpoo l blenn y ar e 6 4 mm(2. 5 in.) T L o r mor e i n siz e befor e the y becom e reproductivel y matur e (Love , 1996) . Som e individual s matur e withi n thei r first year , howeve r

i t i s mor e commo n fo r

blenn y t o becom e matur e i n thei r secon d (Love , 1996) . Th e spawnin g seaso n ofth e thre e Californi aHypsoblennius spp . begin s i n th e sprin g an d ma y exten dint o Septembe r

(Stephen s e t

al. , 1970) . Blennie s ar e oviparou s an d la y demersa l egg s tha t ar e attache dt o th e nes t

substrat e b y adhesiv e pad s o r filaments (Moser , 1996) . I n Hypsoblennius spp. , th e responsibilit y for tendin g th e nes t

reside s wit

h th e male . Female s spaw n 3 t o 4 time s ove r aperio do f

severa l week s (Stephen s e t al. , 1970) . Male s guardth e nes t aggressivel y an d wil l ofte n chas e th e femal e away , however , severa l female s ma y occasionall y spaw n with a singl e mal e (Stephen s e t

al. , 1970) . Th e numbe r

o f egg s afemal e produce s varie s proportionatel y wit

h he r siz e (Stephen s e t

al. , 1970) . Th e smalle r

an d shorter-live d H. jenkinsi carrie s relativel y mor e egg s pe r length than H. gilberti (Stephen s e t al. , 1970) . A femal e musse l E9-053. 9 4-6 3 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.2 4 

# I 8 I

i



# I 

# 1 4. 0 Entrainmen t an d Sourc e Wate rResult s

blenn y H. jenkinsi may carr y 50 0 egg s i n he r first yea r an d u p t o 2,90 0 egg s b y he r thir d year (Stephen s e t

al. , 1970) . Femal e rockpoo l blenn y H. gilberti may produc e fro m60 0 t o 3,20 0 egg s pe r spawnin g (Love , 1996) . Incubatio n tim e i s temperature-dependen t an d egg s typicall y hatc h i n 4 t o 1 8 day s (Love , 1996) . Larva e o f al l thre e specie s ar e pelagi c an d around2. 7 m m(0.1 1 in. ) 2 day s afte r

hatchin g (Stephen s e t

al. , 1970) . Th e planktoni c phas e for Hypsoblennius spp . larva e ma y las t fo r 3 month s (Stephen s e t

al. , 1970 ; Love , 1996) . Stephen s e t al . (1970 ) foun d that , althoug h al l Hypsoblennius spp . larva e wer e th e sam e siz e a t hatching , larva e ofth e rockpoo l blenn y H. gilberti wer e large r

a t th e tim e o f

settlemen t

(1 8 t o 2 1 mm[0.7 1 t o 0.8 3 in.] ) than eithe r th e musse l blenn y o r

ba y blenn y (1 2 t o 1 4 m

m[0.4 7 t o 0.5 5 in.]) . H e assume d tha t th e siz e differenc e wa s th e resul t

o f mor e rapi d growth rathe r tha n alonge r

larva l phase . Th e accelerate d | growth rat e o f th e rockpoo l blenn y continue d throug h th e firs t post-larva l year

a s individual s gre w t o atota l lengt

h o f betwee n 6 5 an d 8 0 mm(2. 6 t o 3. 1 in. ) (Stephen s e t al. , 1970) . Musse l | | an dba y blenn y o f th e sam e ag e average d4 5 m m(1. 8 in. ) in total lengt

h (Stephen s e t

al. , 1970) . Rate s o f larval mortalit y wer e no t availabl e fo r

blennids , bu t

Brother s (1975 ) indicate d that l l 9 9 percen t

larval mortalit y ove r

tw o month s i s reasonabl e for thre e specie s o f

gobie s tha t

ar e ecologica l analogs i n simila r habitats . Dail y surviva l wa s estimate d a s (1-0.99) 1 ' 6 0 = 0.926 dl

. A growth rat e o f

0. 2 mm d_ 1 wa s estimate d usin g th e differenc e betwee n transformatio n lengt h (Moser , 1996 ; 1 0 - 2 2 mm ) an dhatc h lengt h (Moser , 1996 ; 2. 3 - 3. 0 mm ) an d 7 5 day s t o settlemen t

(Fitc h an dLavenberg , 1975) . I t wa s assume d tha t

th e ag e at

entrainmen t

wa s | approximatel y midwa y t o flexion . Th e growth rat e wa s use d t o estimat e th e ag e o f entrainmen t a s 7. 8 days , i.e. , on e hal f

ag e a t flexio n (flexio n lengt

h minu s hatc h length divide d b y growth | ) rate) . Surviva l t o entrainmen t was the n estimate d a s 0.92 6 = 0.55 . Larva l surviva l fro mentrainmen t t o settlemen t

(7 5 days ) was estimate d a s 0.92 6 lo "' ° = 0.0057 . Adul t mortalit y was estimate dfro mag e grouping s o f thre e specie s i n Stephen s e t al . (1970) . Exponentia l instantaneou s mortalit y rate s (Z ) wer e calculate d fro mthes e ag e grouping s usin g th e relationshi p betwee n lo g number s a t ag e In(N t ) an d ag e t: In(N t ) = -Zt+b Th e averag e o f

th e estimate dinstantaneou s mortalit y rate s (H. jenkinsi: Z=0.72 ; H. gilberti: Z=0.57 ; H. gentilis: Z=0.64 ) wa s use d t o estimat e annua l adul t surviva l o f

0.52 5 yr" 1

. Usin g thi s annua l rate , th e surviva l fro msettlemen t t o ag e 3.6 7 year

(averag e ag e use d i n fecundit y hindcasting ) was estimate da s 0.11 . Larva l blennid s ar e no t

difficul t t o distinguis h fro mothe r larval fishe s throug h acombinatio n o f myomer e counts , pigmentatio n pattern s an d thei r elongate d for

m(Moser , 1996) . Th e norther n E9-053. 9 4-6 4 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.2 5

4. 0 Entrainmen t an d Source Wate r Results rang e o f th e ba y blenn y extend s t o Montere y Ba y whil e th e range s o f adul t rockpoo l an d musse l blenn y d o no t

exten dnorth o f

Poin t Conception , Sant aBarbar aCount y (Mille r an d Lea , 1972) . Larva l Hypsoblennius spp . ar e not easil y distinguishe d fro meac h other . Becaus e o f th e lon g pelagi c lif

e phas e ofth e genus , an dth e correspondin g potentia l for long-rang e dispersal , i t

i s possibl e tha t

larva l rockpoo l an dmusse l blenn y coul d occu r i n th e Mos s Landing/Elkhor n Sloug h are aa s wel l a s withi n entrainmen t samples . Fo r

thi s reaso n identification s o f Hypsoblennius spp . larva e wer e not mad e pas t

th e genu s level . Al l Hypsoblennius larva e wer e combine di n th e Hypsoblennius spp . category . Fo r assessmen t

purpose s in Sectio n 6 , w e assum e tha t th e unidentifie dblennie s i n ou r sample s ar e bay blenny . 

### 4.8.2 Blennie s Hypsoblennius spp . Result s (1. 9 percent ) Blennie s comprise d1. 9 percen t ofth e tota l number s o f

larval fishe s collecte d in entrainmen t surveys a t th e ne w C C unit s intak e (Figur e 4-1) . The y wer e no t collecte d in th e entrainmen t survey s unti l Apri l 29 , 199 9 an dwer e presen t i n every surve y fromMa y 1 3 throug h Decembe r 9 , 199 9 (Figur e 4-26) . Larva l blennie s wer e no t collecte d in th e entrainmen t survey s fro m Decembe r

16 , 199 9 throug h Februar y 17 , 2000 . The y wer e collecte d i n lo w concentration s (1.6/1,00 0 m 3 ) durin g th e Februar y 24 , 200 0 survey . Peak concentratio n (272/1,00 0 m 3 ) occurre do n Septembe r

16 , 1999 . Concentration s wer e typicall y belo w 50/1,00 0 m 3 for mos t o f th e tim e perio dsampled . Hypsoblennius spp . Entrainmen t Mea n Concentratio n

25 0

10 0 

### 11 1 •.-.- . Imflliiiitfffm--.i_ttlltiti.llll1tlttitlli t j fc 5 sal s . •_n = s s " 8 = i = g*is"ssB" s:: 88''i*i8*is 8 Figure 4-26. . Mea

n surve y concentration s (#/l,00 0 m 3 ) o f larva l Hypsoblennius spp . a

t th e Mos s Landin g Powe

r Plan t ne w combined-cycl e unit s intake : March 1999 throug h Februar y 2000 . E9-053. 9 4-6 5 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.2 6

4. 0 Entrainmen t an d Sourc e Wate r Result s Th e die l distribution s wer e plotte dfo r concentration s o f

larva l blennie s collecte d i n front o f th e ne w combined-cycl e unit s intak e fro mJun e 199 9 throug h Februar y 200 0 (Figur e 4-27) . W e analyze donl y th e entrainmen t surveys tha t

coincide d with th e sourc e wate r surveys ; n o larva l blennie s wer e collecte di n th e Decembe r 199 9 an d Januar y 200 0 entrainmen t surveys . Th e peak die l concentratio n o f

blennie s occurre d a

t nighttim e betwee n 183 0 an d 023 0 hour s PS T betwee n Jun e an dNovembe r

1999 , excep t

i n Augus t

199 9 an dFebruar y 2000 , whe n th e pea k concentration s occurre da t 065 9 an d145 2 hour s PST , respectively . Blennie s comprise d6. 8 percen t ofth e tota l larva l fishe s collecte d i n th e Elkhor n Sloug h area , 5. 1 percen t

i n th e Mos s Landin g Harbo r area , an d 3. 0 percen t

i n th e Ocea n are afro mJun e 199 9 throug h Februar y 200 0 (Figur e 4-4) . Larva l blennie s wer e collecte d in al l survey s excep t Decembe r

199 9 an dJanuar y 200 0 (Figur e 4-28) . I n Octobe r 1999 , the y wer e collecte d a t al l station s excep t

Ocean South . Th e highes t concentration s occurre d in June , July , an d Augus t durin g lo w tide . Th e highes t peak concentratio n occurre d i n Augus t (503/1,00 0 m 3 ) a

t th e Dairie s station . Larva l blennie s wer e no t identifie di n th e PG& E (1983 ) entrainmen t studie s no r

hav e the y bee n collecte di

n othe r studie s o f

Elkhor n Slough/Mos s Landin g Harbo r (Nybakke n e t

al. , 1977 ; Yoklavich e t

al. , 1992) . Sinc e Montere y Ba y i s th e norther n mos t boundar y o f

th e Hypsoblennius spp . range , i t i s possibl e tha t

thi s i s ane w specie s fo r

thi s area . Hypsoblennius

spp . Larva l Entrainmen t Die l Mea n Concentratio n

i SO O I S S | 60 0 S c i 3 TM

• R- i 

### ...H i •••ni l •



# . 1

• • 1 

### .I n

. - R -

5 5 : 3 "*

* Au g 1 2 Se p 1 6 Oc t 1 4 3*8S8S8S' , -'SB3; * De c 2 9 Ja n 2 0 Fe b 2 4 Note : Thes e entrainmen t survey s wer e conducte d coincidentall y wit h sourc e wate r

surveys . Figur e 4-27 . Concentration s (#/1,00 0 m 3 ) larva l Hypsoblennius spp . a

t the ne w combined-cycl e unit s intak e separate db

y sample collectio n tim

e (PST) : Jun e 199 9 through Februar y 2000 . E9-053. 9 4-6 6 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.2 7

4. 0 Entrainmen t an d Sourc e Wate r Result s

Hypsoblennius

spp . Sourc e Wate r Mea n Concentratio n

E 10 0 • Hig h

• Lo w

000 00^\ 000 

# 1

® 5 ° S i § S 5 ° i i i S 5 ° S i i S 5 ° ! i i 8 5 ° H ? 8 5 ° M S 8 5 ° i i S 8 5 ° i I I 8 5 ° i i 5 S Jun1 6 Ju l 1 2 Aug1 2 Se p 1 6 Oc t 1 4 No

v 1 8 Dec2 9 Jan2 0 Feb2 4 Key— KP: Kirb y Park ; D : Dairies ; HB : Harbo r Bridge ; HM : Harbo r

Mouth ; ON : Ocea n North ; OS : Ocea n South • 0 Station s no t

include d in stud y desig n unti l September . © Sample s voide ddu e t o imprope r preservation . Figure 4-28 . Sourc e wate

r concentration s (#/l,00 0 m 3 ) o f larva l Hypsoblennius spp . a

t six station s nea

r Mos s Landing Powe

r Plant : June 1999 throug

h Februar y 2000 .

E9-053. 9 4-6 7 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.2 8

4. 0 Entrainmen t an d Source Wate r Results 

## 4. 9 Longja

w Mudsucke r Photographe r Dre w Talle y

^5 3 

### Gillichthys

mirabilis Range: Fro mBaji aMagdalena , Baj aCaliforni at o Tomale s Bay , California . I n Arizona : th e Sal t Rive r an d th e lowe r Colorad o River . Introduce d int o th e Salto n Sea , California . Life History: Size : u p t o 21 0 m m(8.2 5 in.) ; Ag e at maturity : on e year ; Fecundity : spawn s tw o t o thre e time s aseason , 4,00 0 t o 9,00 0 eggs ; 8,00 0 t o 27,00 0 egg s (Barlow , 1961) ; Lifespan : tw o years . Habitat: Tida l flats , shallo w mudd y waters . Fishery: Commercia l an drecreational : bait-fis h fishery . Distributio n Ma p fo

r Longja w Mudsucke r 

### Th e longja w mudsucke

r Gillichthys mirabilis i s amediu mt o larg e gob y specie s tha

t commonl y inhabit s bays , estuaries , tida l sloughs , an

dsal t pond s along the Pacifi c coas t o f Nort h America . The nativ e distributio n o

f longja w mudsucker s extend s along the Pacifi c Coas t fro mBaji a Magdalena , Baj aCaliforni ato Tomale s Bay , Californi a(Love , 1996 ; Wang , 1986) . They ar e mos t abundan t fro mSa n Francisc o Ba

y south . A

n isolate dpopulatio n ha s bee n documente di

n th e uppe r reache s o f th e Gul f o f Califomi aan

da n introduce dpopulatio n ha s als o become well establishe di

n th e Salton Sea . Th

e latte r populatio n i s descendedfro m50 0 fish tha

t wer e plante d by CDF G during Novembe

r 193 0 (Barlo w an

dD e Vlaming , 1972) . Longja w mudsucke

r hav e als o bee n reporte di

n Arizon a(Roosevel

t Lak e o n the Sal t River ) an dth e lower

Colorado Rive

r wher e the y ar e commonl

y usedas bai

t (Fuller , 1999) . The occurrenc e o f longja w mudsucke

r i n thes e system s i s though

t to have bee

n derive dfro

mbait bucke t release s (Fuller , 1999) . E9-053. 9 4-6 8 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.2 9 

# 1 1 1 I 1 1 1 1 1 1 1 1 1 4. 0 Entrainmen t an d Sourc e Wate rResult s

Longja w mudsucke r

ar e abl e t o tolerat e awid e rang e o f environmenta l conditions . Th e specie s ar e abundan t

o n tida l flat s an di n shallo w mudd y backwater s (Love , 1996) . The y ca n liv e i n wate r with salinitie s rangin g fro mtw o an d ahal f time s tha t

o f seawate r t o nearl y freshwater , an d ar e abl e t o withstan dwate r temperature s a s hig h a s 35 ° C (95 ° F ) (Love , 1996) . Thei r preferre d temperatur e rang e i s betwee n 9 ° C an d 23 ° C (48 ° F an d 73 ° F ) (D e Vlaming , 1971 ; Love , 1996) . Longja w mudsucke r ar e characterize d a s havin g bi-moda l breathin g capabilitie s (Moyl e an dCech , 1988) . In additio n t o extractin g oxyge n fro mth e wate r wit h thei r gills , mudsucker s hav e th e abilit y t o absorb oxyge n fro mai r take n i n (gulped ) an d hel d i n thei r larg e an d highl y vascularize dbucca l cavit y (Moyl e an d Cech , 1988 ; Love , 1996) . The y als o hav e th e abilit y t o underg o limite dcutaneou s respiratio n throug h thei r fin s (Barlow , 1961) . The y ca n surviv e extende dperiod s o f

tim e ou t o f th e wate r

an d hav e bee n observe d "walking " acros s tida l flat s fro mon e poo l o f

wate r o r burrow t o th e nex t

(Moyl e an d Cech , 1988 ; Todd , 1968) . Mudsucker s ofte n retrea t

int o hole s an dcra b burrow s whe n tida l flat s are expose d durin g lo w tide s (Love , 1996) . I t ha s bee n reporte dtha t

longjaw mudsucke r

ca n liv e ou t o f th e wate r

fo r 6 t o 8 days , i f the y ar e kep t

mois t (Eschmeye r

e t al. , 1983) . Longja w mudsucke r

ar e olive-brow n t o dar

k brow n in colo r

wit h yellowis h bellie s (Mille r an d Lea , 1972) . Juvenile s often hav e 8 dar k bar s dow n th e lengt

h o f thei r bod y an d adar

k blotc h o n thei r first dorsa l fin (Walke r

e t al. , 1961 ; Love , 1996) . Longja w mudsucke r reac h amaximu m siz e o f abou t 21 0 mm(8.2 5 in.) . The y ar e readil y distinguishe d fro mothe r similar-lookin g gobie s b y thei r

disproportionatel y lon g uppe r jaw , whic h extend s t o nea r th e margi n o f

th e gil l opening . Thei r

pelvi c fins fus e t o for

madis c (Walke r

e t al. , 1961) . Th e lif e span o f longja w mudsucke r

i s abou t 2 year s (Walke r

e t al. , 1961 ; Lov e ,1996) . The y becom e sexuall y matur e an dma y spaw n i n thei r first year , whe n the y ar e 2 5 t o 5 1 m m( 1 t o 2 in. ) long . Longja w mudsucke r ar e multipl e spawner s an d hav e bee n documente d spawnin g 2 t o 3 time s ayear

(Walke r e t al. , 1961 ; Wang , 1986) . Spawnin g activit y peak s i n th e sprin g bu t ma y commenc e a s earl y a s Novembe r (i n Sa n Francisc o an d Tomale s bays ) an d extend s throug h Jul y (Barlo w an dD e Vlaming , 1961 ; Wang , 1986 ; Love , 1996) . Th e timin g o f spawnin g i s controlle db y environmenta l cue s suc h a s seasona l change s i n ligh t an d temperatur e (Moyl e an d Cech , 1988) . Female s ar e oviparou s an d la y fro m4,00 0 t o 9,00 0 adhesive , club-shape d egg s whic h ar e attache dt o th e side s ofth e burro w wit h centra l stalk s (Weisel , 1947) . Barlo w (1961 ) reporte dlongja w mudsucke r layin g betwee n 8,00 0 an d 27,00 0 eggs . Th e egg s ar e guarde d b y male s durin g thei r

1 0 t o 1 2 da y incubatio n perio d (a t 18 ° C [64 ° F] ) (Weisel , 1947 ; Wang , 1986) . Larva e ar e pelagi c an d3 t o 4 m m(0.1 2 t o 0.1 6 in. ) T L at hatchin g (Wang , 1986) . The y occu r a t al l level s withi n th e wate r colum n (Barlow , 1963 ; Wang , 1986) . Becaus e o f heav y pigmentatio n observe di n post-larva e a s smal l a s 8 t o 1 2 mm(0.3 1 t o 0.47 ) TL , th e pelagi c larva l phas e o f th e longja w mudsucke r

i s though t

t o b e short

i n compariso n t o th e pelagi c phas e o f sympatri c gob y larva e (Barlow , 1963) . Dependin g o n local hydrographi c conditions , larva e ca n b e disperse d E9-053. 9 4-6 9 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.3 0 

# 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 H 4. 0 Entrainmen t an d Sourc e Wate rResult s

ove r awid e geographi c are ao r remai n relativel y concentrate d nea r thei r nata l habitats . Larva e settl e ou t a t 8 t o 1 2 m mi n lengt

h (0.3 1 t o 0.4 7 in.) an d begi n t o develo p dens e pigmentatio n (Wang , 1986) . Th e growth rat e o f

youn g longja w mudsucke r i s rapi d bu t

varie s seasonally . Fitc h an d Lavenber g (1975 ) provide dagrowth rat e fo r th e first year o f lif e o f 12. 7 cm/yea r

( 5 in. ; o r 0.33 8 mm/day) . A 2 0 da y larva l duratio n wa s estimate d based o n asettlemen t siz e o f 1 0 m man d hatc h siz e o f 3. 5 mm(Wan g 1986 ) usin g th e growth rat e o f 0.33 8 m md- 1 calculate d fro m12 7 m mgrowth in th e firs t year (Fitc h an dLavenberg , 1975) . Larva l mortalit y was assume d t o b e 9 9 percen t ove r th e larval period . Larva l length s range dfro m2. 7 t o 4. 7 m m(mea n 3.8 6 mm ) usin g th e cente r 9 8 percen t o f measure dlengths . Surviva l t o entrainmen t wa s estimate d usin g ag e 3. 4 d , basedon growth fro mth e smallest ofth e 9 8 percen t

interva l t o mean length , a s (1-0.99)3.4/2 0 = 0.455 . Walke r e t al.(1961 ) foun dthat

th e highes t

growt h rate s in th e Salto n Se apopulatio n occurre d durin g th e ho t

summe r months . B y Augus t

th e modal siz e o f

th e sample d young-of-the-year (YOY ) populatio n ha dreache dastandar d lengt h (SL ) o f 6 0 t o 8 0 mm(2. 4 t o 3. 2 in.) (Walke r e t al. , 1961) . Growth rate s ha dslowe db y Decembe r wit h th e moda l siz e of

yearlin g gob y rangin g from8 0 t o 11 5 m

mS L (3. 2 t o 4. 5 in.) (Walke r e t al. , 1961) . Male s wer e observe d t o gro w slightl y faste r

than female s (Walke r

e t al. , 1961) . Longjaw mudsucke r ar e carnivorou s an d juvenile s fee do n avariety o f invertebrate s an d occasionall y o n smal l fishes . Thei r die t include s harpacticoid s an dothe r

copepods , nematodes , an d fl y larva e o f

th e Famil y Heliida e (Walke r e t al. , 1961 ; Wang , 1986) . Muc h o f thei r die t a s adult s i s compose d o f crustacean s suc h a s crab s an dghos t shrim p (Love , 1996) . I n th e Salto n Sea , th e mos t importan t

foo d o f adul t mudsucke r was th e pil e wormNeanthes spp. , althoug h the y als o consume d barnacles , avariet y o f insec t larvae , an da

n occasiona l Deser t

pupfis h (Walke r

e t al. , 1961) . Longja w mudsucke r ar e preye d upo n b y avariet y o f

bird s an dfishes . Longja w mudsucke r

ar e considere dexcellen t bai t an d ar e use d i n avariet y o f recreationa l fisheries. The y ar e considere don e o f th e bes t bait s t o us e fo r

corvin aCynoscion xanthulus in th e Salto n Se a(Walke r

e t al. , 1961) . Mos t

mudsucker s use d for

bai t ar e capture d i n cylindrica l minno w traps . A smal l commercia l bai t fishery exist s for

longja w mudsucke r

i n th e Sa n Francisc o Bay Estuar y an dDelt at o suppl y th e need s o f stripe d bas s fishermen . Annua l landing s o f longja w mudsuckers , reporte di n th e CDF G CMASTE Rdatabase , ar e generall y small . Betwee n 198 7 an d1996 , state-wid e landing s range d fro m1 0 pound s i n 199 4 t o 55 7 pound s i n 1987 . N o landing s wer e reporte din 199 0 o r 1991 . Othe r

source s hav e reporte d mean annua l catche s fo r

th e live-bai t

industr y t o b e aroun d 14,00 0 pounds .

E9-053. 9 4-7 0 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.3 1

4. 0 Entrainmen t an d Source Wate r Results 

### 4.9. 1 Longja

wMudsucke r Gillichthys mirabilis

Result s (1. 2 percent ) Longja w mudsucke r

comprise d1. 2 percen t

o f th e tota l number s o f

larva l fishe s collecte d i n entrainmen t

survey s at

th e ne w C C unit s intak e (Figur e 4-1) . The y wer e collecte d i n al l entrainmen t

surveys fro mMarc h 2,199 9 throug h Februar y 24 , 200 0 (Figur e 4-29) . Pea k concentratio n (43/1,00 0 m 3 ) occurre d o n Novembe r 4,199 9 an d th e lowes t

concentratio n (1.5/1,00 0 m 3 ) occurre don Marc h 8 , 1999 . Longja wMudsucke r Entrainmen t Mea n Concentratio n

* £ 3 5 C 3 0 2 5 

# a m m iifff«{«fjjff!;srfc££ f

-r» w - N tt ^ i .1 . <! , - -r* H li H 1* ' L•

u » • iiiillltltiitiii i a 8 3 » S 8 S 2 8

- * a o » I - S : Ii i B 8 Figur e 4-29 . Mea

n surve y concentration s (#/l,00 0 m 3 ) o f larva l longja w mudsucke

r a t the Mos s Landin g Powe r Plan t ne w combined-cycl e unit s intake : Marc h 1999 through Februar

y 2000 .

E9-053. 9 4-7 1 MLP P 316(b ) Resource Assessmen t 4-28-200 04. 0 Entrainmen t an d Source Wate r Results



### Th e diel distribution s wer

e plotte dfo

r concentration s o

f larva l longja w mudsucke

r collecte d i

n fron t o f th e ne w combined-cycl e unit s intak e fro mJun e 199 9 throug

h Februar y 200 0 (Figur

e 4

- 30) . W e analyze donl

y th e entrainmen

t survey s tha

t coincide dwit

h the sourc e wate

r surveys . Th e die l concentration s o

f larva l longja w mudsucke

r variedbetwee

n nigh t an dday . Th e highes t concentration s occurre da

t nigh t i n th e Septembe

r 199 9 throug

h Januar y 200 0 survey s (Figur

e 4

- 30) . Th e highes t

concentration s occurre di

n dayligh t hour s durin g the Jun e an

dAugus t 199 9 an d Februar y 200 0 surveys . Concentration s wer e nearly equa

l betwee n nighttime anddaytim

e durin g th e July 199 9 survey . Longja w Mudsucke r Larva l Entrainmen t Die l Mea n Concentratio n

J < o 

# 1 

# I I I 

# 1 ll . 1

1 1 1 

# I I I 1 1 

# III . : « " s s " Ju n 1 7 3 3 3 ' Au g 1 2 t a « "

Se p 1 6 = ; : » 8 8 5 « ~i

: a r = 8 8 S " De c 2 9 Ja n 2 0 : : 3 tt s : Fe b 2 4 Note : Thes e entrainmen t survey s wer e conducte dcoincidentall y wit h sourc e wate r

surveys . 

### Figur e 4-30 . Concentrations (#/l,00 0 m 3 

### ) o f larva l longja w mudsucke

r a t th e ne w combined-cycl

e unit s intak e separate db y sampl e collectio n tim e (PST) : Jun

e 199 9 throug h Februar y 2000 . Longja w mudsucke

r comprise d5. 1 percen

t o f the tota l larva l fishe s collecte di

n th e Elkhor

n Sloug h area , 1. 6 percen

t i n the Mos s Landin g Harbor area , an dles s tha n 1 percent

i n the Ocea n are afro mJun e 199 9 through Februar y 200 0 (Figur

e 4-4) . Longja

w mudsucke

r wer e collecte d i

n al l survey s (Figur

e 4-31) . The pea

k hig h tide concentratio n (272/1,00 0 m 3 

### ) occurre da t Kirby Par k i n Jul y 1999 . The pea

k low tide concentratio n (219/1,00 0 m 3 

### ) occurre di n Februar y 200 0 a t Kirb y Park . Longja

w mudsucke

r larva e wer e onl y collecte dtwic e (a

t Ocea n Sout h durin g hig

h tid e i n Novembe

r 199 9 an da t Ocea n Sout h durin g alo

w i n Januar y 2000 ) fro

mth e tw o station s locate din Montere

y Bay .

E9-053. 9 4-72 MLP P 316(b ) Resource Assessmen t 4-28-200 04. 0 Entrainmen t an d Sourc e Wate r Result s

Longjn r MudsuclcerSoui'c e Wata r Mea n Concentratio n

E 100

5 1 0 s • Hig h

• Lo w

000 000 000 

# I -

Ju l 1 2 Au g 1 2 Se p 1 6 Oc t 1 4 No

v1 8 De c 2 9 Ja n 2 0 Fe b 2 4 Key— KP: Kirb y Park ; D : Dairies ; HB : Harbo r Bridge ; HM : Harbo r

Mouth ; ON : Ocea n North ; OS : Ocea n South •$ > Station s no t

include di n stud y desig n unti l September . ® Sample s voide ddu e t o imprope r preservation . 

### Figure 4-31 . Sourc e wate

r concentration s (#/l,00 0 m3 

### ) o f larva l longja w mudsucke

r a t si x station s nea

r Mos s Landin g Powe

r Plant : Jun e 199 9 through Februar y 2000 . Al l longja w mudsucke

r larvae collecte dfro

mth e sourc e wate

r survey s an

dth e ne w combined

cycl e intak

e survey s tha

t corresponde dto sourc e wate r survey s (referredto a s paire dsurveys ) wer e measured . Th e lengt

h frequency distributio n o

f longja w mudsucke

r larvae wa s simila

r throughout

th e sourc e wate

r stud y area . Th e generally unifor mlengt h o f larvae among th e variou s samplin g locations , a s shown i n Figur e 4-32 , provide s littl e insigh t int o hatchin g site s base do n larva l stage . Although th e sampl e siz e o f length-frequenc y varie dwit h concentration s o f larva e among sourc e wate

r samplin g locations , th e shorte r longja w mudsucke

r larvae appea

r t o b e missin g fro

msample s collecte dbot

h th e a t th e Harbor

Bridg e an dHarbor Mout h stations . Thi s sligh t patter n o f shorter to longer larva l lengt h fro mth e uppe

r slough t o Monterey Ba

y wouldpoin

t t o th e inne r slough an dmarshe s as alarva

l source . A muc

h stronger patter n o f decreasin g concentratio n o f longja w mudsucke

r larva e fro muppe r slough to the Monterey Ba y als o point s t o the slough andmarshe s as aprimar y sourc e o f longja w mudsucke

r larvae . Thi s conclusio n i s consistent

wit h ou r knowledg e o

f th e species ' preferre dspawnin g habitat .

E9-053. 9 4-7 3 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.3 4

1 2

1 0

• o £ 6 o V xt E • Kirb y Par k

• Dairie s • Harbo rBridg e D Harbo rMout h • C C Unit s Intak e



# £ 

# u H I 4. 0 Entrainmen t an d Sourc e Wate r Result s Longja w Mudsucke rLengt h Frequenc y 

# I I 1 

# u 3 3. 1 3. 2 3. 3 3. 4 3. 5 3. 6 3. 7 3. 8 3. 9 4 4. 1 4. 2 4. 3 4. 4 4. 5 4. 6 4. 7 4. 8 4. 9 5 Lengt h (mm ) Figur e 4-32 . Lengt

h frequency o

f all larva l longja w mudsucker s Gillichthys mirabilis measure d (n=180* ) b

y sourc e wate

r an dintak e sampling location s (June 1999 through Januar y 2000) . , 1

*C C Unit s intake : N = 47 ; sourc e wate r surveys : N = 13 3

E9-053. 9 4-7 4 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.3 5

4. 0 Entrainmen t an d Sourc e Wate r Result s

Longja w Mudsucke r Lengt h Frequenc y V s Tid eIndividualumberof

0 - • Lo w Tid e D Hig h Tid e 

# 1 

# 1 ni l i 

# 11 - n



## n • " 

# 1 I ( 

# j . 

# . n , 3 3. 1 3. 2 3. 3 3. 4 3. 5 3. 6 3.7 3. 8 3. 9 4 4. 1 4. 2 4. 3 4. 4 4. 5 4. 6 4. 7 4. 8 4. 9 5 Lengt h (mm ) Figur e 4-33 . Lengt

h frequenc y o f al l larva l longja w mudsuckers Gillichthys mirabilis measured (n=180* ) b

y hig h an dlo w tide stag e (Jun

e 1999 throug

h Januar y 2000) . *C C Unit s intake : N = 47 ; sourc e wate rsurveys : N = 13

3 Th e length frequenc y o f

al l longjaw mudsucke r

larva e fro mpaire d survey s i s show n i n Figur e 4-3 3 plotte dalon g wit h lengt h frequenc y o f

sourc e wate r

specimen s collecte d at

hig h an d lo w tid e stages . Tida l stag e appear s t o hav e n o relationshi p t o larva l stage . Difference s i n th e individua l lengt

h o f specimen s wer e sligh t

rangin g fro m2. 5 t o 5. 5 mm ; th e majority o f specimen s wer e betwee n 3. 4 an d4. 5 mm . Al l o f th e individua l length s o f longja w mudsucke r larva e collecte di n paire dsurveys are plotte d b y surve y i n th e Figur e 4-3 4 scattergram . Lookin g a t Figur e 4-3 4 fo r

period s o f

larg e number s o f

smalle r individual s followe d b y period s o f fewe r an dlarge r individual s t o indicat e ahatchin g event , i t i s possibl e tha t

cohort s o f

longja w mudsucker s hatche di n Jul y an dSeptembe r 1999 . Howeve r

th e pattern s ar e slight , an d th e increas e i n length betwee n survey s appear s t o b e les s than expecte d base d o n growth rat e i n a singl e cohort . I t

i s mor e likel y tha t

hatching s occurre d throughou t th e summe r

an d fal l months , an dth e residua l fractio n o f eac h previou s puls e blende d int o th e peak s o f newl y hatche d larvae .

E9-053. 9 4-7 5 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0T""" ' P.3 6 * 1 4. 0 Entrainmen t an d Sourc e Wate r Result s

6.0 0

5.0 0

4.0 0

3.0 0

2.0 0

1.0 0

O.O O 05/20/9 9 Longja w mudsucke rLengt h Vs Tim e

« ( • )

•

• • •

• • • • 

## i •

• • • 

## i * • • • • •

# 

# I • 

## r j i \ }

07/09/9 9 08/28/9 9 10/17/9 9 12/06/9 9 01/25/0 0 03/15/0 0 Figur e 4-34 . Scattergra

mplo t o f larva l longja w mudsucker s Gillichthys mirabilis length s measured (n=180* ) b

y sourc e wate

r surve y dat e (Jun e 199 9 through Januar

y 2000) . *C C Unit s intake : N = 47 ; sourc e wate r surveys : N = 13 3 Longja w mudsucke r

larva e wer e entraine d throughou t th e stud y perio d (Novembe r 197 8 throug h Marc h 1980 ) durin g th e first entrainmen t

study . Th e peak

concentratio n (150/1,00 0 m 3 ) occurre da

t Unit s 1 throug h 5 i n Septembe r 1979 .

E9-053. 9 4-7 6 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.3 7

4. 0 Entrainmen t an d Sourc e Wate r Result s 

## 4.1 0 Pacifi c Herrin g



# ^ 4 i'! ' '^WWW'Wiiini-* ! „ . Clupea pallasi Range: Fro mnorthern Baj aCalifomi at o Toyam aBay , Japan , westwar d t

o th e Yello w Sea . Life History: Size : U

p t o 4 6 c m(1 8 in. ) an d55 0 g 11. 2 lb) ; Ag e a t maturity : tw o t o thre e year s old ; Fecundity : 4.00 0 t o 130,00 0 eggs ; Lif

e Span : Alaska

- t o ninetee n years , California

- t o eleve n years . Habitat: A schoolin g specie s found nea r shor e t o hundred s o

f mile s of f shore ; spawn s i

n intertida l an d sub-tida l zones . Fishery: Commercial : valuabl e ro e fishery ; Recreational : smal l pier

an dshor e angle r

fishery . Distributio n Ma

p fo r Pacifi c Herrin g Pacifi c herrin g belon g t o th e Orde r Clupeiforme s whic h contain s som e of th e world' s mos t numerou s an deconomicall y importan t fishe s (e.g. , herring , sardine , anchovy) . Th e overal l distributio n o f

th e Pacifi c herrin g extend s fro mBaj aCaliforni at o th e nort h Pacifi c an d westwar d t o Japan an dth e Yello w Se a(Mille r an d Lea , 1972) . I

n Nort h America , Pacifi c herrin g rang e fromBaj aCaliforni anorth t o arcti c Alask a(PSMFC , 1999) ; the y ar e mos t abundan t of f Alask a an dBritis h Columbia . I

n California, mos t

o f th e population s ar e foun d i n th e Sa n Francisc o an d Tomale s ba

y area s (Fitc h an dLavenberg , 1975) . Pacifi c herrin g are foun d fro mver y nearshor e area s t o hundred s of

mile s of f th e coas t (Love , 1996) . Pacifi c herrin g ar e small , streamline dmarin e fishes , measurin g up t o 4 6 c m(1 8 in. ) i n lengt h an d weighin g up t o 55 0 g (1. 2 lb ) (PSMFC , 1999) . Thes e slende r fis h are silvery belo w an d bluish

gree n t o oliv e abov e (Love , 1996) . Pacifi c herrin g stock s livin g i n th e water s of

f of Alask aan d Canad aten dt o gro w large r an dliv e longe r

than th e herrin g of

f California . I

n Alaska , herrin g hav e bee n age dt o ninetee n year s ol d an d can measur e 3 8 c m(1 5 in.) i n length . Pacifi c herrin g i n Californi amay liv e t o eleve n year s of ag e an d rarel y excee d 30. 5 c m(1 2 in. ) i n lengt h (Fitc h

E9-053. 9 4-7 7 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.3 8



# 1 1

1

I B

a B 

# 1 • 4. 0 Entrainmen t an d Source Wate r Results



### an dLavenberg, . 1975) . Californi aPacifi c herrin g reach maturit y a t 2 to 3 year s o

f ag e and a t a lengt h o f 16. 5 to 17. 8 c

m(6. 5 to 7 in. ) (Love , 1996) . Pacifi c herrin g exhibi t

importan t behaviora l characteristic s suc

h a s schoolin g anddiurna

l (daily ) vertica l movement . A schoo l start s t o for mwhe n ayoun g juvenil e approache s th e tail o f anothe r juvenile ; bot

h vibrat e rapidly , an

dbegin swimming together . The schoo l increase s i n siz e a s othe r fish join , an dsoo n astead y schoolin g patter

n emerges . A schoo l behave s a s a n individua

l organism , tightenin g into abal l whe n threatene do

r spreadin g ou

t whe n approachin g shallo w o r surfac e waters . Singl e school s o f herrin g hav e bee

n estimate dt

o include man

y million s o

f individual s (Svetovidov , 1963) . Ther e i s asiz e limi

t fo r individual s within aschool ; th e differenc e betwee

n the smalles t

an d larges t herring members i s approximately 5 0 percent , The fishe s above or

belo w the siz e limit

brea k awa y an dfor mne w schools . Th e depth s a

t whic h herrin g swi

mar e relate dt o plankton movement , ligh t intensity , temperature , an

dbreedin g conditio n (Svetovidov , 1963) . Mos t herrin g ar e believe dt

o sta y i n deepe r wate r durin g the da

y an d the n mak e avertica l migratio n fro

m30 0 t o 40 0 m(98 5 to 1,31 2 ft

) towar dth e surfac e a

t night . Thes e diurna

l movement s correspon dt

o th e movemen

t o f plankto n an

dals o t o temperature , as th e fis

h move fro

mdee p colde r water s to warme

r surfac e waters . Th e spawnin g activit

y o f Pacifi c herrin g i s largel

y influencedby thei r

geographica

l location . I

n California , spawnin g i s know n to occu r i n Sa n Dieg o Bay , Sa

n Lui s River , Morr

o Bay , Elkhor

n Slough , Sa n Francisc o Bay , Tomale s Bay , Bodeg aBay , Russia n River , Noy o River , Shelte r Cove , Humbold

t Bay , andCrescen

t Cit y Harbor (Lee t e t al. , 1992) . Fis h begin enterin g protecte dcoasta

l bays , estuaries , an

dshallo w nearshor

e environment s approximately tw o month s prior to spawnin g (Eldridge , 1977) . I n the Mos s Landing an

dElkhor n Sloug h area , spawnin g take s plac e fro

mNovembe

r through Jul y (Hardwick , 1973) . Mos t spawnin g occur s durin g the winter , but

asmall , noticeabl e pea

k occur s fro mJun e to July . The souther n Pacifi c herrin g population s ar

e abl e to spaw

n i n warme r wate r temperature s (18 ° C [64.4 ° F] ) tha n the Canadia

n stock s ( amaximumobserve dspawnin g temperatur e o f 10 ° C [50 ° F] ) (Alderdic e an dVelson , 1971) . The majorit

y o f spawnin g habita

t i s nea r vegetation i

n shallo w water s rangin g fro mth e mea n low-tide level t

o adept h o f approximately 4 m(1 3 ft) . The substrat e o f th e spawnin g ground s tend s t o b e clean , hard , andcovere dwit h gravel . Othe

r substrat e ma y include rocks , pilings , an d jetties . A soft , mudd

y bottomma

y b e usedi f avegetativ e cove

r i s available . Male s an

dfemale s spaw n simultaneously ove

r aperio do f 1 t o 7 day s (Mille

r andSchmidtke , 1956) . The fertilize d eggs , broadcas t

mostly a t night , ar e adhesiv e an

dcommonl

y attach t o eelgrass , algae , and othe r intertida l vegetatio n (Hardwick , 1973) . Thousand s o f female s repeatedly deposit their egg s o n the vegetation , which ca

n result i n eg g masse s fro

m1 0 to 1 5 layer s thick

(about 5 c m[ 2 in.] ) (Love , 1996) . I

n larg e spawnin g runs , a9-m(30-foot ) wid e ban do f herrin g egg s ma

y spa n a distanc e o f 2 0 mile s along the shorelin e (Lee t e t al. , 1992) . I

n Elkhor n Slough , Pacifi c herrin g E9-053. 9 4-7 8 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.3 9 4. 0 Entrainmen t an d Source Wate r Results 

### ar e know n t o broadcas t

egg s o n Salicornia spp . (pickleweed) , abrackis h mars h vegetatio n (Wang , 1986) . Female s ar

e capabl e o

f spawnin g only onc e per

season , andafte

r producin g between 4,00 0 an

d130,000 eggs , the

y promptly retur

n t o th e ocean , leavin g th e egg s t o incubat e an dhatch . Th e rat

e o f eg g developmen

t varie s wit h surroundin g water

temperature ; Pacifi c herrin g egg s commonly hatc h within 1 0 to 1 4 day s a

t 11.8 ° to 13.5 ° C (53.2 ° t o 56.3 ° F ) (Wang , 1986) . Their

salinit y toleranc e rang e i s 8 to 1 8 pp t an dseem s to hav e n o effect

o n eg g developmen

t (Fitch andLavenberg , 1975) . Shortly afte

r hatching , an

das th e eye s becom

e pigmented , th e threadlik

e larvae move towar

d the surfac e waters . They tendto concentrat e nea r th e surfac e an

dremain fo

r alon g time i

n th e are a ofth e spawnin g grounds . Som e larvae , however , have bee n foun dsevera l mile s ou t t o sea , drifting wit

h th e current s (Fitch an

dLavenberg , 1975) . I

t take s abou

t 7 0 day s (Hay , 1985 ) (whe

n larva e ar e approximately 2 6 m

mT L [1. 0 in.] ) fo

r th e larva e t o metamorphose . Metamorphosi s i s complet e b y 3 5 m mTL (1.3 8 in. ) (Stevenson , 1962) . Juveniles , dependin g on geographica l region , rang e fro

m3 5 t o 15 0 m mTL (1.3 8 t

o 5. 9 in. ) (Reilly , 1988) . Herrin g usually reach maturit y i n 2 t o 3 year s i n Californi aan

d3 t o 4 year s i n Washingto n (Hart , 1973) . Pacifi c herrin g ar

e pelagic , an

dwhil e som

e ma y remain i n th e bay s andestuaries , mos t leav e andretur

n to th e ocea

n (Eldridge , 1977) . A

t al l lif e stage s Pacifi c herrin g ar

e plankto n feeders , primarily selectin g copepods , amphipods , fish larvae , an dmollusks . The

y do no t fee d durin g th e spawnin g season , bu t feedintensively i

n the summe

r afte r spawning . Pacifi c herrin g ar

e awel l describe dspecie s wit

h bot h age-andstage-specifi c mortalit y estimate s availabl e fro

mth e scientifi c literature . Eg g mortalit y ha s bee n estimate dto rang e fro

m2 0 percen t (Hoursto n andHaegele , 1980) t o a s hig h a s 9 9 percen

t (Hardwick , 1973 ; Leet

et al. , 1992) . Larva

l mortalit y ca n als o b e derive dfro

mth e literatur

e andi s assume dto b e 9 9 percent through settlemen

t (survivorship = 0.221) . Datao n larva l ag e andgrowt

h (e.g. , Stevenson , 1962 ; Alderdic e andHourston , 1985 ) ar e als o importan

t fo r estimatin g survivorship . Tota l adult mortalit y ha s bee n estimate da s abou

t 5 0 percen t annually (z= 0.69 ) b y Hoursto n andHaegel e (1980) . Estimate s o

f natura l adul t mortalit y (m) ar e i n clos e agreemen

t fro mavariet y o f studies : m= 0. 4 - 0. 5 (Trumbl e an

dHumphreys , 1985) , m = 0.3 9 (Frie dan dWespestad , 1985) , m = 0.3 6 (Schweiger

t andHourston , 1980) , m = 0.5 6 (Gunderson an dDygert , 1988) , an dm = 0.3 1 - 0.7 1 (Stocke r e t al. , 1985) . Pacifi c herrin g ar

e a n importan

t specie s i n the foodchain an

dar e fe dupon , a t al l lif e stages , by man y other specie s includin g ctenophore s (com b jellies) , chaetognath s (arro w worms) , salmon , lingcod , sharks , seabirds , an dmarine mammals . Pacifi c herrin g ar e als o sough

t afte r b y ma n fo r food , bait , an

droe . I n additio n to predation , the y ar e als o subject

t o bein g carrie dout

o f protectiv e bay s an

destuarie s int

o area s wit h littl e o r n o foo dsupply . Despite th e sever e

E9-053. 9 4-7 9 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.4 0

4. 0 Entrainmen t an d Source Wate r Results mortalit y rate , th e recruitmen t o f Pacifi c herrin g remain s hig h du e t o thei r extremel y hig h fecundity , thei r

distribution , an dearl y ag e o f maturity . Th e harves t

o f Pacifi c herrin g i s amulti-millio n dolla r industr y i n th e Unite d States , wit h mos t o f th e fish comin g fro mAlaska , Washington , an d California . Th e Pacifi c herrin g fishin g industry i s highl y regulate dnorth o f San Francisc o Bay . Ther e ar e smal l fisheries i n th e Montere y an d San Francisc o are atha t

targe t Pacifi c herrin g fo r

bai t an dfood , bu t

th e mor e valuabl e fishery involve s herrin g egg s (roe) . Ther e i s aver y lucrativ e expor t

marke t for herrin g roe , especiall y fo r kazunok o komb u (roe-on-kelp ) whic h i s considere d adelicac y in Japan . Ther e ar e alimite d numbe r o f permit s issue dfor

thi s fishery i n San Francisc o Bay . Larg e amount s o f gian t kelp , transporte dfro mth e Channe l Islands , ar e suspende d fromrafts , whic h ar e the n anchore d in th e Pacifi c herrin g spawnin g grounds . A t th e en d ofth e spawnin g period , diver s collec t th e kel p an d attache deggs , pac k

i t i n sal t an dexport

th e hig h price d produc t

t o Japan . Commercia l landin g informatio n on Pacifi c herring , sac-roe , an d roe-on-kel p i s show n in Figur e 4-35 aan d b . (a )

• ; 25 , | 2 0 - 

## 1 15 

## " I 1 0 - ? 5 - 3 ° 0 Q . U H 

# I987 Pacifi c Herrin g an d Sac-Ro e Landing s 

# llll h •ill . ooo>o<-c\ic*><'tn<or^c o flooocncno>o>c*oci>c , oo)cn cncncooicDcbcAcnocnc n g Pacifi c Herrin g fl Herrin g Sac-Ro e

(b ) a : •o 40 0 , c S 30 0 - 3 | 20 0 - » 10 0 - 3 0 - o a1987•1988j1989M Roe-on-Kel p Landing s

O v

C

M C

O ^ w Oi Oi Oi

Oi

Oi

Oi Oi Oi Oi

Oi

Oi

Oi 

# 11996 

# 11997 

# •1998 gRo e o n Kel p

Source: CDFG Landing Tables. Figur e 4-35 . (a) Pacifi c herring , sac-ro e an d (b ) roe-on-kel

p Californi astate-wide landings : 1987 throug h 1998 .

E9-053. 9 4-8 0 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.4 1

4. 0 Entrainmen t an d Source Wate r Results 

### 4.10.1 Pacifi c herrin g Clupea pallasi result s (0.9

percent) Pacifi c herrin g comprise d0. 9 percent o f th e tota l number s o

f larva l fishes collecte di

n entrainmen

t survey s a t th e ne w C C unit s intak

e (Figur e 4-1) . The

y wer e collecte di

n al l entrainmen

t survey s fro

mMarch 2 , 199 9 through Jun e 24,199 9 an dagain i n August , Octobe

r an dDecembe

r 199 9 fro mth e ne w C C unit s intak

e (Figur e 4-36) . They wer

e collecte di

n lo w concentration s i

n the Augus t

3 1 (2/1,00 0 m 3 

### ) , Octobe

r 2 8 (8/1,00 0 m 3 

### ) , andDecembe r 2 , 199 9 (2/1,00 0 m3 

### ) entrainmen

t surveys . N o Pacifi c herrin g larvae wer e collecte ddurin g th e July , September , an

dNovembe

r 199 9 surveys . They wer

e collecte dagain eac

h wee k beginnin g o

n Januar y 20 , 200 0 throug

h Februar y 24 , 2000 . Th e highes t

concentratio n (110/1,00 0 m3 

### ) occurre d o n Februar y 3 , 2000 . Pacifi c Herrin g Entrainmen t Mea n Concentratio n 12 0

| 4 0 S 

## 1.1,1,1.1,1,1 , 

# .L.ll l ,—,—,—,_•.,—,— , A.......... . m ,I, M ,—T-B-JLT J 

# il l fftfi**1*ftfttitt**lm'tmt*i.f1t1111iiitiii i

« s s ' B 8 rti 8 = B « - 8 S i 5 j i 8 - m i j j - S 5 j

j g - • = r . S 8 S 8 

### Figur e 4-36 . Mea

n surve y concentration s (#/l,00 0 m) o f larva l Pacifi c herrin g a t th e Mos s Landin

g Powe r Plan t ne w combined-cycl

e unit s intake : Marc

h 199 9 throug h Februar y 2000 . The diel distribution s wer

e plotte dfo

r concentration s o

f Pacifi c herrin g larvae collecte di n fron t ofth e ne w combined-cycl e unit s intak e fro mJun e 199 9 through Februar y 200 0 (Figur

e 4-37) . Pacifi c herrin g larva

e wer e no t collecte di

n th e July 199 9 through Novembe r 199 9 entrainmen

t survey s tha

t coincide dwit

h th e sourc e wate

r surveys . Pea

k concentration s occurre ddurin g the daytim e i n June 199 9 an

dFebruar y 2000 . I n Decembe

r 199 9 pea k concentratio n occurre d a

t 222 4 hour s PST , an

di n Januar y 200 0 they wer

e onl y collecte da

t 183 0 hour s PST .

E9-053. 9 4-8 1 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.4 2

4. 0 Entrainmen t an d Source Wate r Results

Pacifi c Herrin g Larva l Entrainmen t Die l Mea n Concentratio n

E 6 0 

# 1

1 1 

# I I 1 

# 1 1 

# II I i - = * S 8 Ju n 1 7 Oc t 1 4 l!8K--SSKS B 3 «BSS» a De c 2 9 Ja n 2 0 Fe b 2 4 Ju l 1 2 Au g 1 2 Se p 1 6 Note : thes e entrainmen

t survey s wer

e conductedcoincidentally wit h sourc e wate

r surveys . Figur e 4-37 . Concentration s (#/l,00 0 m 3 ) o f larva l Pacific herring a

t the ne w combined-cycl e unit s intak e separate db

y sample collectio n tim

e (PST) : June 1999 through Februar y 2000 . Pacifi c herrin g larva e comprise d10. 9 percen t ofth e larva l fish tax acollecte d i n th e Elkhor n Sloug h area , les s than 1 percen t i n both th e Mos s Landin g Harbo r an d Ocea n areas . The y wer e no t collecte da

t an y sourc e wate r

station s i n August , September , October , an d Novembe r 199 9 (Figur e 4-38) . Th e peak

concentratio n occurre d a t Kirb y Park

durin g lo w tid e i n Februar y 200 0 (1,815/1,00 0 m 3 ) . Th e peak hig h tid e concentratio n (1,127/1,00 0 m 3 ) als o occurre d a t Kirb y Park i n Februar y 2000 . Entrainmen t

dat ashowe dtw o spawnin g period s fo r Pacifi c herrin g durin g th e first entrainmen t stud y (PG&E , 1983) . Pacifi c herrin g larva e wer e entraine d betwee n Ma y 197 9 an d earl y Augus t 197 9 an dagai n fro mDecembe r 197 9 throug h Marc h 198 0 (Figur e 4-38) . Th e pea k concentratio n (460/1,00 0 m 3 ) occurre da t Unit s 1 throug h 5 i n Januar y 198 0 (PG&E , 1983) . Peak concentration s fro mth e previou s entrainmen t stud y (PG&E , 1983 ) occurre d at Unit s 1 throug h 5 i n Januar y 1980 .

E9-053. 9 4-8 2 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.4 3



# f 

# I

m



# I 1 4. 0 Entrainmen t an d Sourc e Wate rResult s



# i 4«H H R©© k

Orab s FsiinnioD

y Csionerodlai e Roc k cra b ar e decapo dCrustaceabelonging to the infraorde r BrachyuraandFamil y Cancridae . Fou r commercially importan

t cra b species , th e dungenes s cra b Cancer magister, the Pacifi c o r brow n rock cra b Cancer antennarius, the redroc

k cra b Cancer productus, an

dth e yello w rock cra b Cancer anthonyi inhabit

overlappin g range s along the Pacifi c Coas t o f Nort h America . Th e fou r specie s occu

r sympatrically . However , th e relativ e abundanc e o f each differ s geographically (Carroll an

d Winn , 1989 ; Jensen , 1995) . Along th e coas t o f Californi are d rock cra b an ddungenes s cra

b ar e mor e commo n i n th e north , yellow rock

cra b i n th e south , and th e brow n roc k cra b i s generall

y mor e abundan t i n the centra

l region s o

f th e stat e (Carroll and Winn , 1989 ; Parker , 1992) . Roc

k cra b inhabi t avariet y o f substrataincludin g rock , gravel , sand , sandy

silt , an d mu d (Winn , 1985 ; Carrol

l an dWinn , 1989) . Al

l fou r specie s occur

i n th e lo w intertida

l zone . However , th e maximu mdept h rang e reporte dfo

r eac h differs (Morri s et

al. , 1980 ; Carroll an dWinn , 1989 ; Jensen , 1995) . Th e first stag e zoea

e o f slende r roc k cra b Cancer gracilis wer

e collecte di n Elkhor n Sloug h an di n offshor e water s o f Montere y Ba y which suggeste dtha

t adul t female s usedth e are afo

r spawning (Hsueh , 1991) . The carapace s o

f roc k cra b ar e broa dan dgenerally ova

l i n shape , howeve

r th e proportion s an

d dorsolatera

l shap e varie s specie s t

o species . The margin o

f the anterior

half o f th e carapac e o

f eac h specie s i s line dwit

h a n equa l numbe r o f teet h (anterolatera

l teeth ) o n each side o

f the body . Th e characteristic s (number , relativ e size , o r appearance ) o

f thes e teet h are differen

t i n eac h specie s (Schmitt , 1921 ; Carroll an dWinn , 1989) . Th e dorsa

l an dventra l coloratio n o

f th e exoskeleto n als o varie s betwee n th e specie s (Carroll an

dWinn , 1989) . All thre e specie s hav e dark-tippe d claws . Adul

t roc k crab s ar e sexually dimorphi c wit

h male s attainin g alarger

siz e an dgrowin g larger , mor

e robus t chela e (claws) . Th e shap e o

f the abdomina

l fla p o f arock crab , a s wit h all brachyura , i s th e mos t definitiv e externa

l sexua l characteristic . I

n male s th e abdomina l flap s ar e slende r an dnarrow to apoin

t whil e thos e o

f female s ar

e broadandrounded . Detail s o f the reproductiv e behavior

o f roc k crab s hav e no t

bee n wel l documente di

n literature , but ar e though t t o follow apatter

n simila r t o othe r cancri dcrabs . Matin g only occur s immediately afte

r afemale ecdysi s (molt) , whe n sh e i s i n asoft-shelle dconditio n (Carrol l and Winn , 1989) . A mal e rock crab , stimulate db y pheromone s release dfro mth e female befor

e sh e molts , will locat

e an d"embrace " th

e femal e i n aface-to-fac e positio n (Carrol l andWinn , 1989 ; Jensen , 1995) . Thi s embrac e continue s through molting , insemination , andth e initia l hardenin g o f he r exoskeleto n (Carroll an

dWinn , 1989) . Durin g th e inseminatio n phase , th e mal e insert s hi s gonopo d(paire dpleopods ) into the spermatothec ao f th e femal e anddeposit s aspermatophor e (Carroll an

dWinn , 1989 ; Jensen , 1995) . The sper mcontaine di

n the spermatophor

e ca n b e viabl e fo r mor e tha n ayea r an dma y be use db y th e femal

e fo r multipl e spawning s (Carrol l and Winn , 1989) . Followin g mating the spermatophor e harden s to for

maplu g tha

t close s of f th e E9-053. 9 4-8 4 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.4 4 

# § 

# i f i I I I I 4. 0 Entrainmen t an d Source Wate rResults



### spermatothec aan

di s though

t to preven t furthe r matin g b y th e female (Carrol l andWinn , 1989 ; Jensen , 1995) . Fertilizatio n occur s internally a s th e egg s ar e being extrude d(Carrol l an d Winn , 1989) . Eg g extrusio n occur s abou t 1 1 week s afte

r matin g an

dthe female carrie s th e eg g mas s unde r he r abdomina l fla p (attache dt

o seta e o n th e endopodite s o

f th e pleopods ) unti l the egg s hatch (Carroll an

dWinn , 1989) . Ovigerous , or "berried " female s ar

e foun dthroughout

the yea r howeve r thei r season o f pea k abundanc e varie s somewha t fro mspecie s to specie s (Toole , 1985 ; Winn , 1985 ; Reilly , 1987 ; Carroll an dWinn , 1989) . Variation s i n th e siz e o

f afemale' s eg g mas s occu r betwee n individual s an

dspecie s (Carroll an

dWinn , 1989) . Information o

n th e tim e require dfo

r eg g developmen

t an dhatchin g i s not

availabl e fo

r red roc k crabs , howeve

r literatur e suggest s tha

t wate r temperatur

e i s a n importan

t variabl e fo

r brow n an d yello w roc k crab s (Anderson an

dFord , 1976 ; Carroll , 1982) . A s wit h al l decapo dcrustaceans , growt h i n roc k crab s i s a n incrementa

l proces s occurrin g onl

y a t th e tim e o f molting . Newl

y hatche dlarva

e (prezoea l stage ) mol

t t o afirst stag e zoe ai

n les s tha n a n hou r (Carroll an

d Winn , 1989) . Larva

l roc k crab s underg o aserie s o

f 5 zoea l molt s (siz e changes ) an

don e megalopa

l mol t befor e the y bea r an y resemblanc e t

o the adults . Zoe aan

dmegalop s ar

e pelagi c an

d ar e widely disperse dby win

dan dcurrent s ove

r the continenta

l shel f (Carroll an

dWinn , 1989) . Juvenil e crab s begi

n t o settl e ou t o f th e wate r colum n (following the megalopa

l molt) durin g th e lat e spring an

dsumme r (Winn , 1985) . Moltin g event s separat

e th e variou s post-larva

l stages , o r

instars , i n th e lif e o f acrab . Becaus e o

f their rigid exoskeleton , increase s i n th e bod y dimension s o

f acra b ca n occur only afte r molting . Roc k cra b growt h i s characterize das indeterminat e becaus e moltin g an

dgrowt h progres s indefinitely (no termina

l molt ) unti l th e anima l dies . Th e perio do

f time between molt s (intermolt period) lengthen s a s th e siz e o f a n anima l increase s an

dth e proportiona

l growt h (widt h an dweigh t increase ) fro

meac h mol t tend s t o decreas e (Carroll , 1982 ; Carroll an d Winn , 1989) . Wate

r temperatur

e i s among th

e factor s reporte dt

o hav e a n effec t o n the growt

h rat e o f post-larva l crab s (Anderson an

dFord , 1976) . Whil e animal s u p to 7 6 m m( 3 in. ) carapac e widt

h (CW) ma y mol t 2 o r mor e time s i n ayear , the intermolt

period s o f crab s i n thei r later instar s ma

y las t 1 6 month s or

longe r (Carroll , 1982 ; Parker , 1992) . Th e maximu mage attaine dby eac

h o f the roc k cra b specie s i s no t

wel l definedi n literatur e but estimate s (base do

n siz e andgrowt

h curves ) sugges t

tha t som e individual s ma

y liv e fo r a t leas t 6 year s (Carroll , 1982 ; Carroll an d Winn , 1989) . Roc k crab s ar e generalis t

carnivore s an

dassum e the rol e o

f bot h apredato r

andascavenger . The y actively forag e fo

r avariet y o f sessil e an dmobil e animal s includin g snails , clams , echinoderms , an

dcrustacean s (Carroll an

dWinn , 1989) . Becaus e o

f their powerfu l chela e (claws) , adul

t roc k crab s hav e th e abilit

y t o crush an d consum e athick-shelle dmollusk s (gastropod s an

dbivalves ) lik

e cockle s Protothaca staminea (Boulding , 1984 ; Bouldin g an d LaBarbera , 1986) , mussel s Mytilus spp . (Smit h an dPalmer , 1994 ; Dugan , pers . obs. , 1997) , an d E9-053. 9 4-8 5 MLP P 316(b ) Resource Assessmen t 4-28-200 04. 0 Entrainmen t an d Source Wate r Results

abalon e Haliotis spp . (Schie l an dWelden , 1987) . The y als o consum e crustacean s suc h a s hermi t crab s (Morri s e t

al. , 1980 ; Rickett s e t

al. , 1985) , barnacle s Balanus spp . (Rickett s e t al. , 1985) , an davariet y o f

crab specie s includin g smaller , o r newl y molte d (soft) , roc k crabs . Cannibalis m ha s bee n observe din th e closel y relate d dungenes s crab (Gotshall , 1977) . Foo d preference s durin g laborator y cultur e indicat e tha t roc k crab s ar e activ e planktivore s durin g thei r larva l stage s (Rumril l et

al. , 1985) . Roc k

crab s als o hav e ahighl y develope d abilit y t o sens e th e presenc e o f

foo di n th e vicinit y (Carrol l an d Winn , 1989) . Amin o aci d concentration s a s lo w a s 1 0 " n moles/lite r

can b e detecte db y th e animal s olfactory apparatus (Fuzesser y an d Childress , 1975) . Roc k crab s ar e vulnerabl e t o predatio n throughou t thei r lives . However , th e risk i s greatl y diminishe di n adul t

crabs . A hos t

o f planktivorou s fishe s an d invertebrate s consum e pelagi c roc k crab larvae . A s juveniles , roc k crab s are preye d upo n b y avariety o f fishe s a s wel l a s som e invertebrat e species . Th e scorpionfis h Scorpaena guttata, cabezo n Scorpaenichthys marmoratus, barre dsan dbas s Paralabrax nebulifer, an d anumbe r o f rockfis h specie s Sebastes spp . ar e amon g th e man y piscin e predator s ofjuvenil e roc k crab s (Turne r

e t al. , 1969 ; Robert s e t al. , 1984 ; Winn , 1985 , Carrol l an d Winn , 1989) . Th e san d star Astropecten verilli i s know n t o pre y o n juvenil e yello w roc k crab s (Van Blaricom , 1978 , 1982) . On e o f th e primar y predator s o f adul t roc k crab s i s th e souther n se aotte r Enhydra lutris (Carroll , 1982 ; Benech , 1986) . Roc k crab ar e als o afavore dpre y ite mo f octop i (Ambrose , 1984 ) an d ar e consume d b y som e shar k specie s (Talent , 1982) . Large r roc k crab s ar e vulnerabl e t o predatio n b y fishe s an d t o cannibalis mdurin g th e "soft-shelled " perio d followin g amol t (Knowle s an d Carlisle , 1956 ; Carroll , 1982) . Roc k crab s hav e no t

bee n th e focu s o f

adedicate d commercia l fishery unti l relativel y recently . Historicall y the y wer e considere dbycatc h i n trap fisheries targetin g mor e valuabl e specie s an d wer e eithe r

throw n bac k

int o th e se ao r

lef t o n th e shor e t o di e (Dahlstro man d Wild , 1983 ; Winn , 1985) . Smal l roc k cra b landing s hav e bee n reporte d sinc e at leas t th e 1930's , however , a separat e marke t

categor y was not

establishe d fo r

th e grou p unti l 195 0 (Parker , 1992) . Annua l roc k cra b landing s o f

around 20,00 0 pound s wer e reporte d in 195 0 (Heiman n an d Carlisle , 1970 ; Carrol l an dWinn , 1989 ; Parker , 1992) . Th e fisher y gre w a t a n annua l rat e o f

abou t 1 0 percen t fro mth e lat e 1950 s unti l 197 1 (Parker , 1992) . Landing s nearl y double d in 197 2 an d b y 197 5 ha d surpasse d1 millio n pound s fo r th e firs t tim e (Parker , 1992) . State-wid e landing s fro m197 9 throug h 199 8 an dlanding s fro mMontere y Ba y port s fro m198 6 throug h 199 8 ar e show n i n Figur e 4-39 . Durin g th e pas t tw o decade s roc k

cra b landing s hav e average d ove r 1. 3 millio n pound s annuall y (Figur e 4-39 ) (CDF G Landin g Summaries , 1979-1998) . Commercia l fisherme n generall y receiv e aroun d$1.0 0 pe r poun d fo r

whole , liv e roc k

cra b (Parker , 1992) .

E9-053. 9 4-8 6 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.4 6 F T - ' 

# I I 

# i i 

# i I I 

# I I I



# i i i 

# i 4. 0 Entrainmen t an d Sourc e Wate r Result s

(a ) Landing s o f al l Roc k Cra b Marke t Categorie s i n Californi a (197 9 throug h 1998 ) 2,000,00 0 1,800,00 0

M 1,200,00 0 •o c 0 . 800,00 0 600^00 0 400,00 0 200,00 0

o

> © •> - c y c o •* * m t o h - ooo)0-*-wco^»ntDr-o o I s

- 0 0 C

D COCOC O COCOC O C O C O O J Oi O O Oi

Oi Oi Oi Oi Oi Oi Oi

Oi

Oi

O)

Oi

Oi

O OiOiOiOlOiOiOiOiO i Oi

Oi Yea r (b )

Roc k cra b landing s i n Montere y Ba y Port s (198 6 throug h 1998 ) 

# 1 1 1 

# i i 40,00 0 , 35,00 0 • 30,00 0 - 25,00 0 - •o § 20,00 0 • o a 15,00 0 - 10,00 0 • 5,00 0 - • g Sant a Cru z | Montere y QMOS S Landin g 

# 1 1 L l

I ltl-"i i • M | • Bill—, J 198 6 198 7 198 8 198 9 199 0 199 1 199 2 199 3 199 4 199 5 199 6 199 7 199 8 Yea r Source: CDFG Landing Summaries 1979-1998. Figure 4-39 . (a

) Californi astate-wide landing s (lbs ) o f roc k crab s (include s the roc

k cra b market categorie s o

f unspecifiedrock

crabs , brow

n roc k crab , redroc

k crab , an d yello w crab) : 197 9 through 1998 . (b ) Port s o

f Montere y Ba y landing s (lbs ) ofth e marke t categor y "Unspecifie d Roc

k Crab" : 198 6 through 1998 .

E9-053. 9 4-8 7 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.4 7 

# I 

# I I I I 

# J I I |

# 1 I I I 

# I I 

# i l i i 4. 0 Entrainmen t an d Source Wate r Results



### I n additio n t o landing s o

f whol e roc k crab , rock cra b claw s are lande dby gillne t fisherme n who catch the mincidentally , de-cla

w the mandretur

n the mt o the ocean . Whil e rock

cra b claw s wer

e include d i n th e cra b cla w marke t category , the majorit

y o f landing s wer

e compose do

f th e claw s o f shee p cra b Loxorhynchus grandis (D . Parker , CDFG , pers . comm.) . Estimate s o f the percentag e o

f rock cra b claw s i n thes e landing s ar

e not available . Cra

b cla w landing s hav e decline d significantly sinc e th e early 1990 s whe n dept h restriction s fo

r gillnet us e wen t into effect . The specie s compositio n o

f landing s o

f whole roc k crab s i s not

availabl e becaus e they hav e historicall y been lande di

n acombinedmarke

t categor y (Unspecifie dRock

Crab ) andno t separate dby species ; som

e separatio n b

y specie s ha s occurre dsinc e 1995 . However , the bul k o f the landing s ar

e still groupe dint

o the "UnspecifiedRoc

k Crab " marke

t category . Trappin g studie s have provide dsom

e insigh t int o variation s i

n th e seasona

l abundanc e o

f each specie s an

d regiona l difference s i

n specie s compositio n (Selby , 1980 ; Carroll , 1982 ; Carrol l an d Winn , 1989) .

E9-053. 9 4-8 8 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.4 8 

# I I I I I I i i l i i i i i i i i i i 4. 0 Entrainmen t an d Sourc e Wate r Results 

## 4.1 2 Hair

y Roc k Cra b Cancer

jordani Cancerjordani Picture t o com e

Range: Fro mNeah Bay , Washingto n t o Bahf ad e Tortuga , Baj aCalifornia . Life History: Size : male s u p t o 39. 3 m m(1. 5 in.) ; female s t o 19. 5 m

m(0. 7 in.) ; Siz e a

t maturity : n o informatio n available ; Fecundity : n o specifi c informatio n available ; lif e span : n o estimat e available . Habitat: Unde r

rock s in shallo w bays , subtidall y in kel p holdfasts ; intertidall y t o depth s o f 10 4 m(34 0 ft) . Fishery: N o commercia l o r recreationa l fishery .

Distributio n Ma p for

Hair y Roc k

Cra b Th e hair y roc k

cra b i s on e o f

th e smallest

member s o f

th e Famil y Cancridae . Th e specie s range s fro mBahf

ad e Tortuga , Baj aCalifornia , Mexic o t o Neah Bay , Washington , althoug h i t i s rar e north o f Coo s Bay , Orego n (Jensen , 1995) . Hair y roc k cra b occu r

fro mth e intertida l zon e dow n t o depth s o f

104 m(34 0 ft) (Garth an d Abbott, 1980) . The y ar e mos t ofte n observe d unde r

rock s in th e shallo w water s o f

bays , bu t ma y als o b e foun d subtidall y in th e holdfast s o f kelp . I n Montere y Bay , u p t o 7 8 hair y roc k crab hav e bee n documente d pe r m 2 o f kel p holdfas t

(Gart h an d Abbott , 1980) . Th e carapac e o f

th e hair y roc k

crab i s similar

i n shap e t o othe r

cance r crab s an d ha s asmoot

h bu t somewha t irregular surface . Th e leg s an d dorsa l surfac e o f th e carapac e ar e covere d wit h hair . Th e hair y roc k

cra b ma y b e confuse d wit h juvenil e brow n roc k

crab C. antennarius, whic h often hav e ahair y appearanc e (Carrol l an d Winn , 1989) . Anothe r smal l cance r

crab , th e furrowe d roc k cra b Cancer

branneri, als o ha s hai r

coverin g it s carapac e an d legs . Hair y roc k crab s d o no t

hav e th e re dventra l spottin g presen t i n juvenil e C . antennarius (Carrol l an d Winn , 1989) . Th e specie s E9-053. 9 4-8 9 MLP P 316(b ) Resource Assessmen t 4-28-200 0

# 1 I I 1 

# t I I I I I 1 1 I I I I 

# I I I 4. 0 Entrainmen t an d Sourc e Wate r Result s



### als o ha s te n teet h linin g th e anterio r

margin o f th e carapace , instea

do f nin e a s in C. antennarius (Gart h an dAbbott , 1980) . Th e anterolatera l teet h o f hair y rock cra b ar e shar p andstrongly curved , an dar e alternately larg e an

dsmall (Gart

h andAbbott , 1980 ; Carrol l andWinn , 1989 ; Jensen , 1995) . Dorsally , th e carapac e o f th e hair y rock cra b i s dar k brown o r reddis h i n color an dofte n mottle di

n appearanc e (Jensen , 1995) . Ventra l surface s ar

e ligh t an dunifor mi n coloration . The fingers o

f th e claw s ar

e dark-tippe d(Jensen , 1995) . Th e hair y rock cra b i s a smal l Cancer specie s wit

h male s measurin g u

p to 39. 3 m

m(1. 5 in. ) an

dfemale s to 19. 5 m

m(0. 7 in. ) (Jensen , 1995) . Th e lif e spa n o f th e specie s andth e age/siz e a t maturit y i s unknown . Information o

n th e lif e histor y o f th e hair y rock cra b i s scarce . Reproductiv e behavior ca n b e assumedt o follow th

e patter n o f other cancer crabs . Ovigerou s female s hav e bee n foun d i n Monterey Ba

y durin g Octobe

r andNovember . The egg s an dlarva e o f hair y roc k cra b ar e simila r i n siz e t o thos e o f large r roc k cra b specie s (J . Carroll , Tenera , pers . comm.) . Hair y rock cra b larva e have bee n reporte dt

o b e large r tha n thos e o f C . antennarius i

n th e sam e stag e (J . Carroll , Tenera , pers . comm.) . Becaus e o f th e smal l siz e o f adul t female hair

y rock crab , an dth e proportionally larg e siz e o

f individua l eggs , i t ha s bee n suggeste dtha

t th e specie s i s probabl

y les s prolifi c tha

n large r Cancer specie s (J . Carroll , Tenera , pers . comm.) . Basedo n thes e observations , th

e fecundit y wouldprobably b e o

n ascal e o f thousand s o r

ten s o f thousand s o

f egg s instea

do f th e hundred s o

f thousand s o r

million s typica

l o f large r cancer cra b species . I

t i s likely tha t the larval , juvenile , andadult hair y roc k cra b ar e preye dupo

n b y the sam

e assemblag e o f fishe s an d invertebrate s tha

t consum e the larva e an dearly cra b stage s o f other Cancrid species . Becaus e o

f thei r small size , adult

hair y rock cra b probably remain vulnerabl e to predatio n by fish specie s suc h a s cabezo n Scorpaenichthys marmoratus androckfishe s Sebastes spp. , an d smal l octopi Octopus spp . throughout their lives . Th e specie s i s no t

harveste d commercially o

r recreationally . 

### 4.12.1 Hairy

Rock Crab Results (29.3 percent) Hair y rock cra b comprise d29. 3 percent

o f th e tota l numbe r o f entraine dmegalop s a

t th e ne w C C unit s intak e (Figur e 4-1) . They wer

e collecte di

n 1 2 ofth e 4 2 entrainmen

t survey s (Figur

e 4-40) . They wer e collecte dfro

mth e endo

f Augus t 199 9 through mid-Octobe

r 199 9 andagain fro

m mid-Novembe

r 199 9 through th e beginnin g o f Decembe r 1999 . They wer

e collecte dagain i

n lat e Decembe

r 1999 , mid-Januar

y andmid-Februar

y 2000 . Th e pea

k concentratio n (63/1,00 0 m3 

### ) occurre do

n Septembe

r 30 , 199 9 al

l remainin g concentration s wer e belo w 11/1,00 0 m3



### .

E9-053. 9 4-9 0 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.5 0 

# I I 1 I I I I I 1 I 4. 0 Entrainmen t an d Source Wate r Results

Hair y Roc k Cra b Megalop s Entrainmen t Mea n Concentratio n

•C5 0 14 0 8 3 0 3 20



# • I 

# 1 I i i i i ? -

j ? , | | i i r r § r 2S:K*sJ?MS.;c;g«j;s*? s 5 3 2 5S8ii ~ =S S S i i i i 8 s i i i f s ? ? i ? r i * i i

? i i ( 0 —u —tfiK* —— NIMI D —wN*»rtH S O ~ 4 » i f " J ? ° - S 8 S S i Figur e 4-40 . Mea

n surve y concentration s (#/l,00 0 m 3 ) o f hair y roc k cra b megalop s a

t the Mos s Landin g Powe r Plan t ne w combined-cycl e unit s intake : Marc h 199 9 through Februar

y 2000 . Th e die l distribution s wer e plotte dfo r concentration s o f

hair y roc k

cra b megalops . W e analyze d onl y th e entrainmen t

surveys that

coincide d wit

h sourc e wate r

survey s fro mJun e 199 9 throug h Februar y 2000 . Hair y roc k crab megalop s wer e collecte d onl y durin g th e Septembe r throug h Decembe r

199 9 surveys (Figur e 4-41) . Concentration s wer e highes t durin g th e earl y mornin g i n Septembe r

1999 , durin g th e nighttim e in Octobe r an dNovembe r

1999 , an d i n th e afternoo n i n Decembe r

1999 . 

# I i i i i E9-053. 9 4-9 1 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.5 1 

# I i 1 1 I I I I i i i i i 1 f I I i i 4. 0 Entrainmen t an d Source Wate r Results

Hairy Roc k

Cra b Megalop s Entrainmen t Die l Mea n Concentratio n

j ~ 3 5 E

s S 1 5 

### 1 

## 1

Au g 1 2 S £ 8 S "

Se p 1 6 Oc t 1 4 Fe b 2 4 Note : Thes e entrainmen t survey s wer e conducte d a t th e sam e tim e a s th e sourc e wate r surveys . Dat aar e preliminary . Figur e 4-41 . Concentration s (#/l,00 0 m 3 ) o f hair y roc k roc k megalop s a

t th e ne w combined-cycl e unit s intak e separate db

y sample collectio n tim

e (PST) : June 1999 throug

h Februar y 2000 . Hair y roc k

cra b megalop s wer e collecte d i n th e September , October , Decembe r 1999 , an d Februar y 200 0 sourc e wate r surveys (Figur e 4-42) . Peak concentration s occurre d durin g th e hig h an d lo w tide s (169/1,00 0 m 3 an d79/1,00 0 m 3 , respectively ) a t th e Ocea n Nort h Statio n o n Decembe r

29 , 1999 . Hair y roc k

cra b megalop s wer e collecte d predominatel y at Ocea n North , Ocea n South , an dHarbo r Mouth stations . The y wer e neve r collecte d a

t th e Kirb y Park , Dairie s an d collecte donl y onc e i n Octobe r 199 9 a t th e Harbo r

Bridge .

E9-053. 9 4-9 2 MLP P 316(b ) Resource Assessmen t 4-28-200 0

# r P.5 2

4. 0 Entrainmen t an d Sourc e Wate r Results

Hairy Roc k

Cra b Megalop s Sourc e Wate r Mea n Concentratio n

14 0 E 12 0 

### I r 10 0

s I 6 0 3 • Hig h Tid e

• Lo w Tid e

000 000 000\ i 1 

# 1 1 

# II I j © | j 

### i 1

Ju l 1 2 Au g 1 2 Se p 1 6 Key— KP: Kirb y Park ; D : Dairies ; HB : Harbo r Bridge ; HM : Harbo r

Mouth ; ON : Ocean North ; OS : Ocea n Sout h <3 > Station s not

include din stud y desig n unti l September . © Sample s voide ddu e t o imprope r preservation . Figure 4-42 . Sourc e wate

r concentration s (#/l,00 0 m 3 ) of hair y roc k cra b megalop s a

t six station s nea

r Mos s Landing Powe

r Plant : June 199 9 throug

h Februar y 2000 .



# E E9-053. 9 4-9 3 MLP P 316(b ) Resource Assessmen t 4-28-200 04. 0 Entrainmen t an d Source Wate r Results



## 4.1 3 Yellow Roc k

Cra b Cancer

anthonyi

Cancer anthonyi Photographer : Da n Duga n

Range: Fro

mHumbold

t Bay , Californi at

o Bajia Magdalena , Baj aCalifornia . Life History: Adul

t crab s sexuall

y dimorphic ; size : male s to 17 6 m

m(6. 9 in.) , female s reac

h 14 4 m m(5. 6 in.) ; siz e a t maturity : 9 0 t

o 10 0 m m(3. 5 t o 3. 9 in. ) fo

r laboratory-reare d animals ; fecundity : 680,00 0 t o 3.8 5 million eggs ; lif

e span : no estimat

e available . Habitat: Sof

t substrate s suc

h a s sand , sandy-silt , an

d mud ; occu r i n the vicinit

y o f roc k reef s or artificia l structures ; the lowe

r intertida l zone t o depth s exceeding 13 0 m(427 ft) . Fishery: Moderat

e commercia

l fishery , smal

l recreationa

l fishery . Distributio n Ma

p fo r Yellow Cra

b 

### Th e yello w cra

b Cancer anthonyi Rathbun occur s alon g th e Pacifi c Coas t o f Nort h Americ afro

m Humbold t Bay , Californi ato Baji aMagdalena , Baj aCaliforni a(Jensen , 1995) . Withi n thi s rang e their distributio n i s almos t

exclusively associate dwit

h san dsubstrata(Winn , 1985 ; Carroll an d Winn , 1989) . The specie s i s mos t abundan t o n the expanse s o

f open , sand

y substratatha

t characteriz e muc

h o f th e Souther

n Califomi aBight . I

t is , however , als o commonl y encountere d nea r th e rock-san dinterfac e o

f natura l an dartificia l reef s i n th e region (Morris , 1980 ; Carroll an d Winn , 1989) . Yellow cra

b ar e als o common underneat

h an di n the vicinit

y o f offshor e oil an d ga s platform s sout

h o f Point Conception (Pag e e

t al. , 1999) . I

n th e norther n part s o f their range , wher e rock y benthi c substratapredominate , their distributio n appear s t o b e confine dmor e t o E9-053. 9 4-9 4 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.5 4 4. 0 Entrainmen t an d Sourc e Wate rResult s 

# 1 1 1 I 1 1 1 1 1 1 1 1 1 1 1 bays , sloughs , andestuarie s (Jensen , 1995) . Yellow roc k cra b occur fro mth e lowe

r intertida l zon e to depth s exceedin g 13 0 m(427 ft ) but ar e mos t commonl y foun din depth s betwee

n 1 8 to 5 5 m(5 9 t o 18 0 ft ) (Morri s e

t al. , 1980 ; Winn , 1985 ; Carrol l an dWinn , 1989 ; Jensen , 1995) . The y ar e th e mos t abundan t cance r cra b specie s harveste di

n southemCalifornia , ofte

n composin g 7 0 t o 9 5 percent o f the tota l cra b catch i n the region (Carrol l andWinn , 1989) . Durin g diver

survey s of

yello w rock

cra b population s i

n Sant aMonic aBa

y i t wa s note dtha

t th e specie s wa s never

see n durin g dayligh

t hour s i n the vicinit

y o f traps , but wer e ofte n abundan t i n th e trap s th e next

mornin g (R . Hardy , CDFG , pers . comm.) . Thes e observation s sugges t tha t yello w rock

cra b ar e nocturnally activ e i

n shallo w wate

r an dremain burie dandinactiv e durin g dayligh t hours . Th e carapac e o

f th e yello w rock

cra b i s simila r i n shap e to tha

t o f th e brown rock

crab , bu t i s proportionally large

r an dconve x dorsolatera

l l y (domed) . It s surfac e i s smoot h an dther e ar e te n anterolatera

l teet h extendin g along th e anterior margi n o f eac h side o f the body . Th e anterolatera

l teet h ar e wide r an dles s acut e tha n thos e o f th e brow n roc k crab . Th e carapac e i s wides t betwee n the nint h anterolatera

l teet h (Carrol l an dWinn , 1989) . Dorsally , the yellow roc k cra b varie s fro

mligh t brow n t o yellow o r orang e i n color (Carroll an

dWinn , 1989 ; Jensen , 1995) . Ventra

l surface s ar

e aunifor mligh t yellow wit

h n o redspecklin g (Carrol l an dWinn , 1989) . Th e walkin g leg s ar e als o yello w or

orang e i n colo r an dgenerally do no t

hav e hai r (Carroll an dWinn , 1989 ; Jensen , 1995) . Th e tip s ofth e claw s ar e dar k (Carrol l an

d Winn , 1989) . Lik e the brown roc

k crab , adult

yellow rock

cra b ar e sexuall y dimorphic , wit

h male s attainin g a large r siz e an dgrowin g larger , mor

e robus t chela e (claws) . Mal e crab s gro w to amaximu msiz e o f 17 6 m m(6. 9 in. ) whil e female s reach 14 4 m m(5. 6 in. ) (Jensen , 1995) . N o estimate s ofth e lif e spa n o f yello w rock

cra b wer e cite di n th e literatur

e reviewed . A laboratory-reare dfemale yello w cra b becam e sexually matur

e afte r moltin g to the thirteent

h insta r (Anderso n andFord , 1976) . Th e molt

occurre dwhe

n th e cra b wa s 40 0 day s ol dan

dhadapost-mol t

carapac e widt

h o f 9 8 m m(3.8 6 in. ) (Anderso n an

dFord , 1976) . Ovigerou s female yello w roc k crab s ar e foun dthroughou

t the yea r (Toole , 1985 ; Winn , 1985 ; Reilly , 1987) , however , the y ar e mos t commo n during the winte

r andsprin g month s (Reilly , 1987) . Th e siz e o

f afemale' s eg g mas s i s variabl e an dca n contain fro

m680,00 0 t

o 3.8 5 millio n egg s (Carroll andWinn , 1989) . The clutch siz e i n yellow roc

k crab s i s reporte dto averag e 2. 6 millio n egg s (Carroll an

dWinn , 1989) . Developmen t o f the egg s andsubsequen

t hatchin g take s 7 t o 8 week s a

t ambien t temperature s o

f 10 ° to 18 ° C (50 ° t

o 64 ° F ) (Anderso n andFord , 1976 ; Carroll , 1982) . Yellow rock cra b egg s hav e hatche di

n 4 3 day s a

t aconstant temperatur

e o f 17 ° C (63 ° F ) (Carrol l an

dWinn , 1989) . Larva

l developmen

t wa s accelerate dsignificantly b y a wate r temperatur

e increas e o

f 4 ° C (7.2 ° F ) fro

m18 ° to 22 ° C (64 ° to 72 ° F ) (Anderso n an d Ford , 1976) . Becaus e o

f th e shortene dduratio n o

f eac h insta r a t 22 ° C (72 ° F) , th e tota

l tim e E9-053. 9 4-9 5 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.5 5 r r - * * * * : . ••>- * 

## 1 I 4. 0 Entrainmen tan d Sourc e Wate r Result s | require d fo r

larva l developmen t

was cu t t o 3 3 day s a s compare d with 4 5 day s a t 18 ° C (64 ° F ) (Anderso n an dFord , 1976) . Difference s i n post-larva l growth i n yello w crab s hav e bee n I attribute dt o wate r temperatur e (Anderso n an d Ford , 1976) . 

## | 4.13. 1 Yello

w Roc k Cra b results (19. 6 percent

) Yello w roc k

cra b comprise d19. 6 percen t o f th e tota l numbe r

o f entraine d Cancer

spp . megalop s • a

t th e ne w C C unit s intak e (Figur e 4-1) . The y wer e collecte d i n al l C C unit s intak e entrainmen t surveys fro mNovembe r

4 , 199 9 throug h Decembe r 21 , 199 9 an d agai n i n th e Januar y 1 3 an d 20 , m 200 0 survey s (Figur e 4-43) . Th e highes t concentration s occurre d i n Decembe r 199 9 (peak • concentration , 16.3/1,00 0 mo n Decembe r 16 , 1999) . Al l othe r

concentration s wer e belo w 3.4/1,00 0 m 3

. 

# 1 | Yello w Roc k Cra b Megalop s Entrainmen tMua n Concentratio n

1 6 - H 1 4 - 

### f g,2- H S 8 8

• 5 6 

### • 1

4 

## 1 2 

# ! • i 

# •lli l l l

• • ? : ? M ' f M s f

? ' n ? ? f

* J ! ? 8 f

» ! ' • = ' » • • * ! * • ! ' ' • s « 8 • aS- i saf e s~ S = : s " 8 Sj ' j : 8 " ; i » ' ° i s i " : ! s ' i : i i m Figure 4-43 . Mea n surve y concentration s (#/l,00 0 m 3 ) o f yellow roc

k cra b megalop s a

t the Mos s 1 Landin g Powe r Plan t ne w combined-cycl e unit s intake : Marc h 1999 through Februar

y 2000 . i i

• : 1 Th e die l distribution s wer e plotte dfor concentration s o f

yello w roc k

cra b megalops . W e B analyze d onl y th e entrainmen t survey s tha t

coincide d wit

h sourc e wate r

survey s fro mJuri e 199 9 H throug h Februar y 2000 . The y wer e collecte d onl y in th e Novembe r 199 9 an d Januar y 200 0 ; | surveys durin g on e cycl e a t nigh t (023 6 an d 183 0 hour s PST , respectively ) (Figur e 4-44) . i : 1

E9-053. 9 4-9 6 MLP P 316(b ) Resourc e Assessmen t • 4-28-200 0

• • ;

*P.5 6

4. 0 Entrainmen t an d Source Wate r Results

Yello w Roc k

Cra b Megalop s Entrainmen t Die ! Mea n Concentratio n

1 2 E § 1 0 5

S 6 S 2 4

; 3

B 1 1 5*i-"uI* ; *58»5 : '*;S3* S

Ju l 1 2 Au g 1 2 Se p 1 6 t! » 8 S * De c 2 9 Iiii '

Ja n 2 0 s « a : •

Fe b 2 4 Note : Thes e entrainmen t survey s wer e conducte da t th e sam e tim e a s th e sourc e wate r surveys . Dat aare preliminary . Figur e 4-44 . Concentration s (#/l,00 0 m 3 ) o f yello w roc k

cra b megalop s at

th e ne w combined-cycl e unit s intak e separate d b y sampl e collectio n tim e (PST) : Jun e 199 9 throug h Februar y 2000 .

E9-053. 9 4-9 7 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.5 7

4. 0 Entrainmen t an d Source Wate r Results Cancer anthonyi megalop s wer e onl y collecte d a t th e Ocea n South Statio n durin g ahig h tid e (concentratio n = 8.4/1,00 0 m 3 ) o n Decembe r 29 , 199 9 (Figur e 4-45) .

" E 6

< B 4 u * c 

# u Yello w Roc k Cra b Megalop s Sourc e Wate r Mea n Concentratio n

• Hig h Tri e • Lo w Tid e



### 1

i 000\ 000 0O0 © £ Z Vt -0 m Z W T £ z w -o S Z « T < a m z w **

3 Au g 1 2 Se p 1 6 No v 1 8 Key— KP: Kirb y Park ; D : Dairies ; HB : Harbo r Bridge ; HM : Harbo r

Mouth ; ON : Ocea n North ; OS : Ocea n Sout h <3 > Station s no t

include din stud y desig n unti l September . ® Sample s voide ddu e t o imprope r preservation . Figur e 4-45 . Sourc e wate

r concentration s (#/l,00 0 m 3 ) o f yello w rock

cra b megalop s a

t si x station s nea

r Mos s Landing Powe

r Plant : Jun e 1999 through Februar y 2000 .

E9-053. 9 4-9 8 MLP P 316(b ) Resource Assessmen t 4-28-200 04. 0 Entrainmen t an d Sourc e Wate r Result s



## 4.1 4 Brow n Roc k

Cra b Cancer

antennarius

Cancer antennarius Photographer : Da n Duga n Range: Fro mQuee n Charlott e Sound , Britis h Columbi a t o Cab o Sa

n Lucas , Mexico . Life History: Adul t

crab s sexuall y dimorphic ; size : male s t o 17 8 m

m( 7 in.) , female s t o 14 8 m m(5. 8 in.) ; siz e a t maturity : 6 0 t o 8 0 m

m(2. 4 in . t o 3. 1 in.) ; fecundity : 410,00 0 t o 2.7 9 millio n eggs ; lif e span : estimate d t o b e 5 t o 6 years . Habitat: A variety o f

substrate s includin g rock , gravel , sand , an dsandy-silt . Occur s fro mth e lowe r intertida l t o depth s exceedin g 10 0 m(32 8 ft. ) Fishery: Smal l recreationa l fishery ; moderat e commercia l fishery .

Distributio n Ma p for

Brow n Roc k

Crab Th e Pacifi c o r

brow n roc k

crab Cancer

antennarius Stimpso n i s distribute d i n nearshor e water s alon g th e Pacifi c Coast

o f North Americ afromQuee n Charlott e Sound , Britis h Columbi at o Cab o San Lucas , Mexic o (Jensen , 1995) . Althoug h i t i s reporte d t o b e abundan t i n Barkle y Sound , Britis h Columbi a(Jensen , 1995) , th e specie s rang e o f peak abundanc e extend s fro mSa n Francisc o Ba y t o coasta l area s sout h ofth e U.S.-Mexic o borde r (Carrol l an d Winn , 1989) . Brow n roc k

crab ar e amarin e specie s that inhabi t nearshor e coasta l region s bu t ma y als o b e foun di n slough s an destuaries . The y are , however , unabl e t o osmoregulat e an d d o not tolerat e brackis h condition s wel l (Gart h an dAbbott, 1980) . Brow n roc k crab inhabi t

avariet y o f E9-053. 9 4-9 9 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.5 9 4. 0 Entrainmen t an d Source Wate r Results substrate s includin g rock , gravel , sand , an d sandy-sil t (Winn , 1985) . The y occu r fro mth e lowe r intertida l zon e t o depth s exceedin g 10 0 m(32 8 ft ) bu t ar e typicall y foun d nea r

th e rock-san d interfac e i n depth s o f

les s tha n 5 5 m(18 0 ft) (Carrol l an d Winn , 1989) . Juvenil e brow n roc k crab inhabitin g th e intertida l zon e surviv e exposur e t o th e ai r durin g lo w tid e b y shelterin g themselve s unde r

rock s an dalga e (Ricketts , 1985) . Th e carapac e ofth e brow n roc k cra b i s generall y oval in shap e an d relativel y fla t dorsolatera l l y wit h a n irregular

bu t otherwis e smoot

h surface . Nin e anterolatera l teeth lin e th e anterio r margi n o f th e carapac e o n eac h sid e o f th e body . Th e carapac e i s wides t betwee n th e eighth anterolatera l teeth (Carrol l an dWinn , 1989) . Th e dorsa l surfac e o f th e carapac e i s generall y amottle d brow n colo r bu t may rang e fro morange-re d t o gray . Ventra l surface s ar e ligh t (whit e t o cream ) i n coloratio n wit

h reddis h specklin g (Carrol l an d Winn , 1989) . Th e re d specklin g o n th e ventra l surface s i s adistinguishin g characteristi c o f th e specie s an d i s no t

presen t o n othe r cancri d crabs . Anothe r distinguishin g characteristi c of th e specie s i s th e tw o pair s o f antenna e (on e long , on e short an dstout ) that

originat e betwee n th e retractabl e ey e stalk s (Carrol l an d Winn , 1989) . Th e walkin g leg s o f

brow n roc k

crab s may b e hairy , especiall y i n juvenile s an d female s (Carrol l an d Winn , 1989) . Adul t

crab s ar e sexuall y dimorphic , wit h male s attainin g alarge r siz e an d growin g large r mor e robus t

chela e (claws) . Mal e crab s gro w t o asiz e (maximu mcarapac e widt h [CW] ) o f 17 8 m m( 7 in. ) whil e female s reac h 14 8 m m(5. 8 in.) (Jensen , 1995) . Th e lif e span o f brow n roc k cra b i s estimate dt o b e 5 t o 6 year s (Carroll , 1982) . Ovigerou s femal e brow n roc k crab s ar e foun d throughou t th e year (Toole , 1985 ; Winn , 1985 ; Reilly , 1987 ) however , the y ar e mos t commo n durin g th e winte r month s (Carroll , 1982) . Th e siz e o f afemale' s eg g mas s i s variabl e an d can contai n fro m410,00 0 t o 2.7 9 millio n egg s (Carrol l an dWinn , 1989) . Developmen t o f th e egg s an d subsequen t hatchin g takes 7 t o 8 week s a t temperature s o f

10 ° t o 18 ° C (50 ° t o 64 ° F ) (Anderso n an d Ford , 1976 ; Carroll , 1982) . Siz e (CW ) increase s i n th e brow n roc k crab rang e fro m7 t o 2 6 percen t pe r molt , whil e increase s i n bod y weigh t

o f 5 0 t o 7 0 percen t

hav e bee n measure d (Carroll , 1982) . Th e sexe s underg o amol t t o maturit y (5 0 percen t

maturit y valu e of

populatio n usin g Somerton , 198 0 method ) fro m betwee n 6 0 m man d8 0 mm(CW ) (2. 4 in . an d 3. 1 in.) (Carroll , 1982) . Brow n roc k crab s ar e estimate dt o g o throug h 1 0 t o 1 2 molt s befor e reachin g sexua l maturit y (Parker , 1992) . 

### 4.14. 1 Brow n Roc k

Cra b Result s (19. 0 percent ) Brow n roc k

cra b comprise d19. 0 percen t o f th e tota l numbe r

o f entraine d Cancer

spp . megalop s a t th e ne w combined-cycl e unit s intak e (Figur e 4-1) . The y wer e collecte d i n 1 4 o f th e 4 2 entrainmen t

collection s a

t th e ne w combined-cycl e unit s intak e (Figur e 4-46) . Highes t concentration s occurre di n tw o survey s i n Septembe r 199 9 (bot

h concentration s wer e approximatel y 9/1,00 0 m 3 ) an dagai n in Januar y 200 0 (9.5/1,00 0 m 3 ) . Al l othe r concentration s fro mth e ne w C C unit s intak e entrainmen t surveys wer e belo w 5.1/1,00 0 m 3

. E9-053. 9 4-10 0 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.6 0

4. 0 Entrainmen t an d Sourc e Wate r Result s

Brow n Roc k

Cra b Megalop s Entrainmen t Mea n Concentratio n

" E 7

1 1 • 

# I 1 , 1



# 1 1 • > 

# 1 iiifif?*f?illiriirst||»| »

<*<-> - »(i o *^ s -• U , «W-*QS ; f f I f ? ? j ? ? ? | I 5 I * —3 S

! " ? S - « • wo-- * t O ( 0 U ^IS> 0 * . —C B s s Figur e 4-46 . Mea

n surve y concentration s (#/l,00 0 m) o f brow n roc k cra b megalop s a

t th e Mos s Landin g Powe

r Plan t ne w combined-cycl e unit s intake : March 1999 through Februar y 2000 . Th e die l distribution s wer e plotte dfo r concentration s o r

brow n roc k

crab megalops . W e analyze donl y th e entrainmen t survye s that

coincide d wit

h sourc e wate r

survey s fro mJun e 199 9 throug h Februar y 2000 . The y wer e collecte d i n th e Augus t throug h Novembe r

199 9 an d th e Januar y 200 0 entrainmen t surveys . Th e highes t

concentration s occurre d a t approximatel y 024 0 hour s PS T durin g th e Septembe r throug h Novembe r

199 9 surveys . In Januar y 200 0 the y wer e onl y collecte da

t nighttim e a

t 183 0 an d 221 9 hour s PS T (Figur e 4-47) .

E9-053. 9 4-10 1 MLP P 316(b ) Resourc e Assessmen t 4-28-200 04. 0 Entrainmen t an d Sourc e Wate r Result s

Brow n Roc k

Cra b Megalop s Entrainmen t Die l Mea n Concentratio n P.6 1

i a 1 5

- 1 

# 1 1 j 

# I I 1 

# 1

S S * 5 ' Ju l 1 2 Au g 1 2 t t s e " Sep 1 6 ! 1 ( ! ' De c 2 9 858S"-SSt!*:

- Note : Thes e entrainmen

t survey s wer

e conducted a

t th e sam e tim e a s th e sourc e wate

r surveys . Dat

aar e preliminary . Figur e 4-47 . Concentration s (#/l,00 0 m 3 ) o f brow n roc k

roc k megalop s a t

th e ne w combined-cycl e unit s 

### intak e separate db y sampl e collectio n tim e (PST) : Jun

e 199 9 throug h Februar y 2000 . Brow n roc k cra b megalop s wer

e predominately collecte da t th e Ocea n Nort h an dOcea n Sout h station s (Figur

e 4-48) . Pea

k concentratio n (25.1/1,00 0 m 3 

### ) occurre do

n alow tide a

t the Ocea n Nort h statio n o n Decembe

r 29,1999 . They wer

e only collecte da

t th e Harbo r

Mout h Statio n during alow tide o

n Februar y 24 , 2000 . The

y wer e neve r collecte da

t th e Kirb y Park , Dairies , or Harbo r Bridg e station s fro

mJune 199 9 through Februar y 2000 .

E9-053. 9 4-10 2 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.6 2

4. 0 Entrainmen t an d Source Wate r Results

Brow n Roc k

Cra b Megalop s Mea n Sourc e Wate r Concentratio n

2 5 • Hig h Tid e • Lo w Tid e

000 000 000 •



# r i

i ! ® Au g 1 2 Se p 1 6 Key— KP: Kirb y Park ; D : Dairies ; HB : Harbo r Bridge ; HM : Harbo r

Mouth ; ON : Ocea n North ; OS : Ocea n South O Station s no t

include din stud y desig n unti l September . © Sample s voide ddu e t o imprope r preservation . Figure 4-48 . Sourc e wate

r concentration s (#/l,00 0 m 3 ) o f brow n roc k cra b megalop s a

t si x station s nea

r Mos s Landin g Powe

r Plant : Jun e 199 9 throug

h Februar y 2000 .

E9-053. 9 4-10 3 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.6 3 4. 0 Entrainmen t an d Source Wate r Resull s 

## 4.1 5 Dungenes s Cra b Cancer magister

Cancer magister Source : CDF G Range: Fro mPribilo f

Islands , Alask at o Poin t Conception , California . Life History: Size : male s t o 23 0 m m( 9 in.) , female s t o 16 5 m m(6. 5 in.) ; ag e at

maturity : on e an dahal f

years ; fecundity : 700,00 0 t o 2. 5 millio n eggs , spawn s onc e a year ; lif e span : t o 8 years . Habitat: Commo n subtidall y t o 9 0 m(29 5 ft) ; a s dee p a s 23 0 m(75 0 ft) . Fishery: Recreational , larg e commercia l market .

Distributio n Map fo r

Dungenes s Cra b 

### Dungenes s cra

b occu r i n Pacifi c coasta

l water s fro

mPribilo f Islands , Alaskato Point

Conception nea r SantaBarbara , Californi a(Jensen , 1995) . The y ar e one o f the larges t

andmos t commercially importan

t crab s along th e Pacifi c Coast . Th e norther n coas t o f California , includin g th e Bodeg aBa

y an dSa n Francisc o area , support s asizabl e dungenes s cra b population , whil e smalle

r population s occu

r i n the Montere

y Ba y an dMorr o Bay/Avil aBeach are a (Dahlstro man

dWild , 1983) . Fiv e sub-population s ar e reporte dto exis t

i n Californi awater s i

n th e followin g areas : 1 ) Avil aBeach/Morr o Bay , 2 ) Monterey Bay , 3 ) Sa n Francisco , 4 ) For

t Brag g t o Cap e Mendicino , an

d5 ) Eureka/Crescen

t Cit y (Gart h an dAbbott , 1980) .

E9-053. 9 4-10 4 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.6 4



# 1 1

B 4. 0 Entrainmen t an d Source Wate r Results

Dungenes s cra

b ar e confine dmainl y t o col d an d temperat e water s wit h annua l mea n temperature s rangin g betwee n 4 ° an d 24 ° C (40 ° t o 75 ° F ) (Gart h an d Abbott , 1980) . Adul t dungenes s crab commonl y occu r subtidall y t o 9 0 m(29 5 ft ) residin g o n sand y bottom s an d i n eelgras s beds , bu t

ma y b e foun da s dee p a s 23 0 m(75 0 ft ) (Jensen , 1995) . Estuarie s ar e importan t t o thei r lif e cycle , an ddungenes s crab ar e though t t o inhabi t

al l estuarie s fro mMorr o Bay , Californi at o Puget

Sound , Washingto n (PSMFC , 1999) . Dungenes s crab ar e beig e t o ligh t brow n o n to p an d ligh t

orang e t o crea mbelow ; coloratio n varie s littl e betwee n individual s excep t for asligh t purpl e t o blu e contras t

i n thei r claw s an d leg s (Jensen , 1995) . Mal e dungenes s crab ca n measur e u p t o 23 0 m m( 9 in. ) i n carapac e width , howeve r the y ar e mor e commonl y foun d measurin g les s tha n 19 0 m m(7. 5 in.) . Carapac e width in female s i s approximatel y 16 5 m m(6. 5 in.) (Gart h an d Abbott , 1980) . Matin g o f

dungenes s crab , betwee n hard-shelle d male s an d soft-shelle d (recentl y molted ) females , occur s in th e near-shor e ocea n i n th e vicinit y o f estuaries . O n th e centra l coas t o f California, matin g occur s fromMarc h throug h Ma y (Wil d an d Tasto , 1983) . Th e female s hol d sper minternall y unti l Septembe r t o Novembe r

a t whic h tim e spawnin g begin s an d last s throug h Decembe r

(Garth an dAbbott , 1980) . Th e egg s ar e fertilize d an d th e sponge-lik e mas s o f 700,00 0 t o 2. 5 millio n egg s i s carrie d o n th e female' s abdome n unti l late-Decembe r (Wil d an d Tasto , 1983 ) throug h Februar y (Garth an d Abbott , 1980) . Egg s start hatchin g i n Decembe r

an d reac h apeak

in Marc h (Gart h an dAbbott , 1980) . Afte r hatching , dungenes s crab exis t i n apre-zoea l stag e for

approximatel y 1 0 t o 1 5 minute s (Reilly , 1983) . Durin g th e nex t 10 5 t o 12 5 days , larva l developmen t o f dungenes s crab progresse s throug h fiv e zoea l stage s (approximatel y 8 0 t o 9 5 days ) t o amegalopa l stag e (approximatel y 2 5 t o 3 0 days ) (Wil dan d Tasto , 1983) . Size s rang e fro mapproximatel y 2. 5 mm (0.2 5 in.) for

stag e on e zoea e t o 11. 0 m m(0.4 3 in.) for megalopa e (Poole * 1966) . Al l larva l stage s ar e planktoni c an dth e zoea e ten d t o mak e vertica l die l migration s whic h kee p the mi n th e to p 1 5 t o 2 5 m(4 9 t o 8 2 ft ) ofth e wate r

colum n b y da y an d i n surfac e water s b y nigh t (Reilly , 1983) . Th e surfac e current s carr y th e larva e offshore , causin g mor e lat e stag e zoea e t o b e distribute dfarthe r

out t o se atha n th e earl y stag e zoea e (Wil d an d Tasto , 1983) . I n Californiawaters , megalopa e transfor mint o juvenil e dungenes s cra b i n Apri l throug h June . Youn g megalopa e trave l towar dth e coas t wit h th e ai d o f

tida l current s an d als o b y attachin g themselve s t o th e bell s o f jellyfis h an d th e tentacle s o f Velella velella (Clas s Hydrozoa ) (Garth an d Abbott , 1980) . Th e megalopa e mol t int o first juvenil e instar s whic h the n settl e i n shallo w coasta l waters , estuaries , an dtida l flats . Livin g o n eelgras s bed s an d othe r aquati c vegetation , th e juvenile s gro w int o adult s throug h aserie s o f molts ; i t take s approximatel y on e an d ahal f year s an deleve n t o thirtee n molt s t o reac h maturit y (Gart h an d Abbott , 1980 ; Wil d an d Tasto , 1983) . Afte r

reachin g maturit y (a t

acarapac e widt h o f

abou t 1 0 c m[ 4 in.] ) dungenes s E9-053. 9 4-10 5 MLP P 316(b ) Resource Assessmen t 4-28-200 04. 0 Entrainmen t an d Source Wate r Results



### cra b mol t an dmat e onl y onc e ayear . Th

e lif e spa n fo r dungenes s cra

b i s abou t eigh t year s (Butler , 1961) . Dungenes s cra

b ar e carnivorous , eatin g smalle r crustaceans , shrimps , molluscs , clams , worms , an doccasionally fishes . Dungenes s cra b are als o a

n importan

t prey species . Adult

dungenes s cra b ar e eate n b y harbor

seals , sealions , andhumans . Cra b larva e ar e eaten b y Pacifi c herring , Pacifi c sardines , rockfishes , an dsalmon . Juvenil e dungenes s cra b ar e fe dupo n by starr

y flounder , lingcod , rockfishes , sturgeon , Englis h androc k sole , sharks , andskate s (PSMFC , 1999) . Marin e worms , particularly Carcinonemertes errans, prey on th e fertilize degg s of dungenes s cra

b (Gart h an dAbbott , 1980) . The centra l Califomi acra

b fisher y bega n t o declin e i

n the early 1960' s andth e dungenes s cra b populatio n stil l remain s a

t lo w level s today . A numbe

r o f factor s hav e bee

n investigate dan

d suggeste da s t

o th e caus e of

thi s decline . It

i s possibl e tha

t pesticides , urba

n pollutants , an

d sewag e hav e contribute dt

o th e mortalit

y o f larva l an dadult crab s (Gart

h an dAbbott , 1980) . Dungenes s cra

b cannot tolerat e condition s of

lo w dissolve doxygen . Contaminants , eve n i n lo w concentrations , ar

e highly toxi c t

o dungenes s crab . Predatio n o n megalopa

e b y Columbi aRive

r salmon ha s bee

n suggeste da s acaus e fo

r th e reductio n i

n recruitmen

t o f cra b along th e centra

l coas t (Wildan dTasto , 1983) . A s larg e number s o f Coh o salmon bega

n to b e successfull

y introduce dfro

mthe Columbi aRive

r hatcheries , th e dungenes s cra b populatio n bega

n t o decline . Th e chang e i

n th e ocea n climate , includin g highe

r se alevels , increase dwate

r temperatures , an

d greate r intensit y ofth e Davidso n Current , appear s t o hav e contribute dto th e dungenes s crabs ' decline . Highe

r wate r temperature s reduc e eg g surviva l an dhatchin g success , an

dma y limit ovar y development . Wit

h th e increas e i

n th e forc e ofth e Davidso n Current , man y cra b larva e ma y b e drifting northward , leavin g centra l Californi awit

h decrease drecruitment

(Wil dand Tasto , 1983) . Dungenes s cra

b landing s throughout

Californi ahav e varie dthrough th e years . Landing s wer e highes t in th e Sa n Francisc o are aunti l th e 194 4 to 1945 seaso n (Dahlstro mandWild , 1983) . Sinc e tha t time , th e majorit

y o f dungenes s cra

b landing s hav e been in norther n California . The Morr o Bay/ A vil aBeach an

dMonterey area s ar

e i n th e souther

n par t ofth e crab' s range , and hav e neve r contribute dsignificantly t

o th e dungenes s cra

b fishery. Figure s 4-49 aandb sho w reporte d commercia

l dungenes s cra

b landing s andvalue s fo

r th e Monterey andMos s Landin g area s fro m1987 to 1998 .

E9-053. 9 4-10 6 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.6 6 4. 0 Entrainmen t an d Source Wate r Results (a ) Dungenes s Cra b Value s an d Landing s fo r th e Montere y Area * 198 7 t o 199 8 T $35 0

- - $30 0

- $25 0

- - $20 0

- - $15 0

- - $10 0

- - $5 0 (

A •a re(thouValue

Im re •••Pound s Lande d —• —Dolla r Valu e $ 0 o a (b ) Dungenes s Cra b Value s an d Landing s fo r Mos s Landin g 198 7 t o 199 8 $14 0 $12 0 $10 0 $8 0 $6 0 $4 0 $2 0 $ 0DollarValue(thousands • • • Pound s Lande d

• Dolla r Valu e

Source: CDFGLanding Summaries 1987-1998. Figure 4-49 . Dungenes s cra b landing s (lbs ) an

d valu e (dollars ) of

landing s fro

m1987 through 199 8 fo

r (a) Monterey Ba

y ports * and(b ) th e por

t o f Mos s Landing . (•include s Monterey , Mos s Landing , an d Sant aCruz) .

E9-053. 9 4-10 7 MLP P 316(b ) Resource Assessmen t 4-28-200 0r 4. 0 Entrainmen t an d Source Wate r Results



### 4.15.1 Dungeness

Crab Results (14.7 percent) i Dungenes s crab s comprise d14. 7 percen t o f th e tota l numbe r

o f entraine d Cancer

spp . megalop s collecte di n th e ne w C C unit s intak e surveys . The y wer e collecte d i n al l survey s fro mmid-Apri l 199 9 throug h Jun e 3,199 9 (Figur e 4-50) . Peak concentratio n (10.1/1,00 0 m 3 ) occurre d o n Ma y 20,1999 . Th e lowes t

concentration s (1.2/1,00 0 m 3 ) occurre d o n Apri l 2 9 an d Ma y 27,1999 .

Dungenes s Cra b Megalop s Entrainmen t Mea n Concentratio n



# 1 l l 

# II I 1 i n H . 

### u J 

### i i i 1

1 n n ^ n $ n 5 

### n H 

### n n ? n ! • s ( 

### * ! s .*?&£ > z N H ~ ^ * --u . ... . m S I " 8 <* > •* : 8 8 r 2 8 Figur e 4-50 . Mea

n surve y concentration s (#/l,00 0 m 3 ) o f dungenes s cra

b megalop s a

t the Mos s Landing Powe r Plan t ne w combined-cycl e unit s intake : Marc h 199 9 through Februar

y 2000 . Dungenes s cra b megalop s wer e not collecte d a

t an y sourc e wate r

station s fro mJun e 199 9 throug h Februar y 2000 . I t i s importan t

t o not e tha t

sourc e wate r

collection s di d no t

begi n unti l Jun e 16,199 9 after

th e dungenes s crab megalop s wer e collecte d in entrainmen t surveys a

t th e ne w combined-cycl e unit s intake .

E9-053. 9 4-10 8 MLP P 316(b ) Resource Assessmen t 4-28-200 0rr r " 4. 0 Entrainmen t an d Source Wate r Results



## 4.16 Re d Roc k Cra

bCancer

productus

Cancer productus Source : CDF G Range: Fro mKodiak

Island , Alask at o Isl aSan Martin , Baj aCalifornia . Life History: Adul t

crab s sexuall y dimorphic ; size : male s t o 20 0 m

m(7. 8 in.) , female s t o 15 8 mm(6. 2 in.) ; fecundity : 560,00 0 t o 1.0 1 millio n eggs . Habitat: Har d substrat e suc h a s rock y reefs , well

protecte d boulder-strew n beaches , an dgrave l beds . Occu r fro mth e lowe r

intertida l zon e t o depth s o f a t leas t 9 1 m(29 9 ft) . Fishery: Recreational ; smal l commercia l fishery .

Distributio n Ma p for

Re d Roc k

Cra b 

### Th e red rock

cra b Cancer productus Randall occur s along th e Pacifi c Coas t o f Nort h Americ a fro mKodia k Island , Alask

ato Isl aSa

n Martin , Baj aCaliforni a(Jensen , 1995) . Base do n th e low densitie s o f re drock crab s collecte ddurin g trappin g studie s i n Sa n Dieg o County , i

t i s commonl

y contende d tha

t souther n Californi adefine s th e southemexten t ofth e specie s rang e (Winn , 1989) . Th e abundanc e o

f redroc k crab , relativ e t

o the othe r roc k cra b species , increase s wit

h latitude within th e state . Redroc

k cra b inhabit avariet y o f substrataincludin g intertida l an dsubtida l rock y areas , gravel , coars e sand , an dmud(Carroll an

dWinn , 1989) . They ar

e commonly foun

d i n clos e associatio n wit

h har dsubstratumsuc

h a s rock y reefs , well-protecte d boulder-strew n beaches , an

dgravel bed s (Morris , 1980 ; Carroll an dWinn , 1989 ; Jensen , 1995) . Redrock cra b occu r fro mthe lowe

r intertida l zon e t o depth s o f a t leas t 9 1 m(29 9 ft

) (Winn , 1985 ; Carroll an

d E9-053. 9 4-10 9 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.6 9 4. 0 Entrainmen t an d Source Wate r Results 

# 0 

# fl Q 0 0 0 Q Q 

# 0 0 8 0 0 B 0 0 Winn , 1989) . Juvenil e re droc k crab inhabitin g th e intertida l zon e surviv e exposur e t o th e ai r durin g lo w tid e b y shelterin g themselve s unde r rock s an d alga e (Ricketts , 1895) . Re d roc k cra b ar e ofte n collecte di n bays , estuaries , an d sloughs , however , thei r distributio n i n thes e area s i s affecte db y salinit y gradient s becaus e th e specie s lacks th e abilit y t o osmoregulat e (Garth an d Abbott , 1980) . Th e carapac e o f

th e re droc k

cra b i s simila r

i n shap e but

mor e laterall y elongat e tha n th e carapac e o f

brow n roc k

crab s o r yello w crabs . Ther e ar e te n anterolatera l teeth linin g th e anterio r margin s o f

th e carapac e alon g eac h sid e of th e body . Th e carapac e i s wides t betwee n th e eight h anterolatera l teet

h (Schmitt , 1921 ; Carrol l an d Winn , 1989) . Anterolatera l teeth ar e no t equa l in siz e i n re droc k

cra b an dbecom e large r

an d mor e acut e posteriorl y (Schmitt , 1921 ; Carrol l an dWinn , 1989) . A shel f o f 5 equally-space d teet

h protrude s betwee n th e eye s fro mth e frontal margi n o f

th e carapac e (Carrol l an d Winn , 1989) . Thi s shel f i s on e o f th e mos t distinguishin g characteristic s o f th e specie s a

t al l size s (Carrol l an d Winn , 1989) . Adul t red roc k crab s ar e generall y auniformreddis h colo r dorsally , bu t

may als o hav e amottle d appearanc e (Carrol l an dWinn ; 1989 , Jensen , 1995) . Ventra l surface s ar e uniformin appearanc e an d typicall y rang e fro moff-whit e t o ligh t yello w i n coloratio n (Carrol l an d Winn , 1989) . Whil e ther e i s n o ventra l specklin g (red ) i n re d roc k crab , th e dorsa l surface s o f th e walkin g leg s ma y hav e aspeckle dappearance . Th e tip s o f th e claw s ar e dar

k (Carrol l an d Winn , 1989) . Juvenil e redroc k cra b ar e highl y variabl e i n dorsa l coloratio n an d displa y awid e arra y o f patterns . Th e backgroun ddorsa l coloratio n i n juvenile s ma y consis t o f variation s o f

green , yellow , red , o r white . Dorsa l pattern s includ e zebra-lik e stripes , multicolore d bands , vermiculations , blotches , speckling , an duniformcolors . Lik e th e brow n roc k cra b an d yello w crab , adul t red roc k crab ar e sexuall y dimorphic , wit

h male s attainin g alarge r siz e an d growin g larger , mor e robus t chela e (claws) . Mal e crab s gro w t o amaximu msiz e (CW ) o f 20 0 m m(7. 8 in.) , whil e female s reac h 15 8 m m(6. 2 in. ) (Jensen , 1995) . N o estimate s o f th e lif e spa n o f re d roc k cra b wer e cite d i n th e literatur e reviewed . Th e siz e o f

afemale' s eg g mas s i s variabl e an d can contai n fro m560,00 0 t o 1.0 1 millio n egg s (Carrol l an dWinn , 1989) . N o informatio n abou t th e developmen t

an d subsequen t

hatchin g o f redroc k cra b egg s was availabl e i n reviewe d literature . Tras k (1970 ) foun d tha t

re d roc k cra b larva e develope dt o th e megalopa l stag e in 9 7 day s a t atemperatur e o f

11 ° C (52 ° F) , however , non e o f hi s laboratory-reare dlarva e survive d t o th e first crab instar . 

### 4.116- 1 Re d R®e k

Cra b Result e (9M

p>ere®nt ) Re droc k cra b comprise d9. 8 percen t o f th e tota l numbe r

o f entraine d Cancer

spp . megalop s a

t th e ne w C C unit s intak e (Figur e 4-1) . The y wer e collecte d i n 1 2 o f th e 4 2 entrainmen t

survey s (Figur e 4-51) . Th e peak

concentratio n (8.3/1,00 0 m 3 ) occurre d o n Ma y 20 , 1999 . Concentration s remaine da t o r belo w 2.0/1,00 0 m 3 for

al l remainin g surveys . E9-053. 9 4-11 0 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.7 0 4. 0 Entrainmen t an d Source Wate r Results

Re d Roc k

Cra b Megalop s Entrainmen t Mea n Concentratio n



## 1 1 

# 1 1 I lll l II I 

# 1 1 III I II I •ss:B8S?«?:?g!ii : 5*8 - » « s ;2 g t S I I I I 8 g f I ! i j f j f j f F S f | I I 5 8 s f - s 5 R j 8 S S Figur e 4-51 . Mea

n surve y concentration s (#/l,00 0 m 3 ) o f re d roc k cra b megalop s a

t the Mos s Landin g Powe r Plan t ne w combined-cycl e unit s intake : Marc h 1999 throug

h Februar y 2000 . Th e die l distribution s wer e plotte dfo r concentration s of

re d roc k crab megalops . W e analyze d onl y th e entrainmen t

survey s tha t

coincide d wit

h sourc e wate r

survey s fro mJun e 199 9 throug h Februar y 2000 . The y wer e collecte d onl y at nigh t i n Jul y an d Novembe r

199 9 durin g on e cycl e (223 1 an d023 6 PST , respectively ) (Figur e 4-52) .

E9-053. 9 4-11 1 MLP P 316(b ) Resource Assessmen t 4-28-200 04. 0 Entrainmen t an d Source Wate r Results

Re d Roc k

Cra b Megalop s Entrainmen t Die l Mea n Concentratio n P.7 1

i 4 m S i » s

S 3 J = 8 : = S i I S Au g 1 2 Se p 1 6 Ja n 2 0 Fe b 24 Note : Thes e entrainmen t survey s wer e conducte d a t th e sam e tim e a s th e sourc e wate r surveys . Dat aar e preliminary . Figur e 4-52 . Concentration s (#/1,00 0 m 3 ) o f red roc k roc k megalop s a

t the ne w combined-cycl e unit s intak e separatedb

y sample collectio n tim

e (PST) : Jun e 1999 through Februar y 2000 . Re droc k cra b megalop s wer e not

collecte d i n an y sourc e wate r survey s fro mJun e 199 9 throug h Februar y 2000 . I t

i s importan t

t o not e tha t

th e sourc e wate r

collection s di d not

star t unti l Jun e 16 , 199 9 after

th e peak concentratio n occurre d a t th e ne w combined-cycl e unit s intake . Ocea n an dHarbo r

Mout h station s wer e no t adde d t o th e samplin g desig n unti l Septembe r 1999 .

E9-053. 9 4-11 2 MLP P 316(b ) Resource Assessmen t 4-28-200 04. 0 Entrainmen t an d Source Wate r Result s



## 4.1 7 Slende r Roc k

Cra b Cancer

gracilis

Cancer gracilis Photographer : MaGa w Range: Fro mPrinc e Willia mSound , Alask at o Bahf a Play aMaria , Mexico . Life History: Size : male s t o 11 5 m m(4. 5 in.) , female s t o 8 7 m m(3. 4 in.) ; ag e at

maturity : approximatel y 1 0 month s o f

ag e (post-settlement) , abou t 6 0 m m(2. 4 in.) ; fecundity : spawn s onc e aseason , 143,00 0 t o on e millio n eggs ; lif e span : approximatel y 4 years . Habitat: Sand y an d mudd y bottom s o f intertida l area s t o 17 4 m(57 1 ft) , kel p an d eelgras s beds , seasonall y i n bay s an d sloughs . Distributio n Ma p for

Slende r Cra b 

### The slende

r crab , occasionally calle dgracefu l crab , ar e foun dfro mPrinc e Willia

mSound , Alaskat o Bahf aPlay aMaria , Mexic o (Jensen , 1995) . They inhabi t th e sand y andmudd

y bottom s o f intertida l area s an dar e foun dsubtidally , ofte

n i n kelp bed s t

o depth s o f 174 m (57 1 ft ) an di n eelgras s bed s (Gart

h an dAbbott , 1980) . Slende

r cra b do not osmoregulat

e an d therefor e canno t tolerat e low salinit

y brackis h environments . They ar e usually not

foun di n estuaries , bu

t ma y b e foun dseasonally i

n bay s an dslough s (Jensen , 1995) . Slende r cra b ar e ofte n misidentifie da s dungenes s crab , but ar e muc h smalle r i n size . Thei r carapac e widt

h measure s u

p t o 11 5 m m(4. 5 in. ) i

n male s an

du p to 8 7 m m(3. 4 in. ) i

n female s (Jensen , 1995) . Their

white-tippe dclaw s lac

k th e serration s belongin g t o dungenes s cra b an d their purpl e walkin g leg s ar

e slender . E9-053. 9 4-11 3 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.7 3 

# i I i 

# i I § i § 

# i i i 

# i i 

# i 

# i i 

# t 

# I i 4. 0 Entrainmen t an d Source Wate r Results



### I n Monterey Bay , spawnin g o f slende r cra b hav e bee n reporte dt o occu

r i n th e sprin g andfal

l (Graham , 1989) . I

n Elkhor n Slough , matin g i s common in Novembe r andovigerou s female s ar

e foun d i n th e sloug

h durin g July an

dAugus t (Gart h andAbbott , 1980) . Female s produc e on e batch per year , although i

n alaborator

y setting , som

e female s produce dasmal l secondbatch . Th e numbe

r o f egg s extrude dpe

r female ca n rang e fro

m143,000 to on e million . Female s ar e abl e to spaw

n fo r a t leas t two , an dpossibly thre e seasons , ove r their lifetim e (Orensan z an

d Gallucci , 1988) . Afte r hatching , slende

r cra b exis t i n apre-zoea

l stag e fo r aver y shor t tim e befor e moltin g to first stag e zoeae . Slende

r cra b progres s through fiv

e zoea l stage s to amegalop s stag e in a n averag e o

f 48. 9 day s a

t 17 ° C ; each stag e lastin g approximately on e wee k (Alley , 1975) . Al

l larva l stage s ar e planktoni c andthe cra

b larva e ma y becom e widel y distributed . I

n Monterey Bay , concentration s o

f first stag e zoea

e hav e bee n foun dfro m6 to 1 1 k

m(3. 7 to 6. 8 miles ) offshor e durin g the sprin g an

dlat e summe r (Graham , 1989) . Othe

r larva l stages , includin g megalopae , ar e foun d distribute doffshor

e a t al l time s o f the year . I

t i s estimate dtha

t slende r cra b matur e a t a siz e o f abou t 6 0 m m(2. 4 in. ) carapac e widt

h an da t approximately 1 0 month s o f ag e (post

settlement) (Orensan z an

dGallucci , 1988) . Slende

r cra b mol t approximately 1 1 to 1 2 time s and liv e fo r abou t 4 years . I n Monterey Bay , young slende r cra b ar e a n importan

t foo dsourc e fo

r th e starr y flounde r Platichthys stellatus (Gart h andAbbott , 1980) . Slende r cra b feedo n barnacle s andbivalves , sometime s causin g problem s fo r th e commercia

l oyste r fishery . Som

e adult s ar e occasionall y take n in th e sportfishery . 

### 4.17. 1 Slende rRoc k

Cra b Result s (7. 1 percent ) Slende r rock cra b comprise d7. 1 percen

t o f th e tota l numbe r o f entraine dCancer

spp . megalop s (Figur e 4-1) . The y were collecte din th e March 14,199 9 survey an dagain in Novembe r 199 9 through mid-Februar

y 200 0 survey s (Figur

e 4-53) . Highes t

concentration s occurre do

n Januar y 20,200 0 andFebruar

y 3 , 200 0 (4.0/1,00 0 m 3 

### an d3.2/1,00 0 m3 

### , respectively) . Fo r all remainin g survey s concentration s wer e a t o r belo w 2.0/1,00 0 m.

E9-05 3 9 4-11 4 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.7 4 

# I I § 

# I I 

# i

-y 

# I 

# i I i i 

# i i 

# t i i i i 4. 0 Entrainmen t an d Source Wate r Results

Slende rRoc k

Cra b Megalop s Entrainmen t Mea n Concentratio n

4. 0 3. 5 3. 0 2. 5 - 2. 0 £ 1- 5 1. 0 

# 1 

# 1 1 1 1



# n

: t: j ! s " s = s IWWWl l sSK?c:83*r' s i j j g " i i

t 8 " ; 

### Figur e 4-53 . Mea

n surve y concentrations (#/l,00 0 m 3 

### ) o f slende r roc k cra b megalop s a

t th e Moss Landin g Powe r Plan t ne w combined-cycl

e unit s intake : Marc

h 199 9 throug h Februar y 2000 . Th e diel distribution s wer

e plotte dfo

r concentration s o

f slende r rock cra b megalops . W

e analyze donly th e entrainment survey s tha

t coincide dwit

h sourc e wate

r survey s fro

mJun e 199 9 through Februar

y 2000 . They wer

e collecte di

n onl y one cycl e pe

r survey (Figur

e 4-54 ) i n Novembe r (123 6 hour s PST) , Decembe r (153 4 hour s PST) an

dJanuar y 200 0 (183 0 hour s PST) .

E9-053. 9 4-1-1 5 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.7 5 

# 1 I 

# i i i 

# I t 4. 0 Entrainmen t an d Sourc e Wate r Result s

2 5

E 2 0 § J c 0 * 5 1 5 t. c • m 3 

## I"

5 Slende rRoc k Cra b Megalop s Entrainmen t Die l Mea n Concentratio n

. 

# i i i i i 

# i i 

# t i t i i aj . 3 B s s w Ju l 1 2 a - 8 3 s 3 : s : 3 t t 9 i Au g 1 2 Se p 1 6 5 s ; a ; s t s a B Oc t 1 4 No

v1 8 De c 2 9 S8S-"3BEi

- Ja n 2 0 Fe b 2 4 Note : Thes e entrainmen

t survey s wer e conducte d a t th e sam e tim e a s th e sourc e wale r surveys . Dat

aar e preliminary . Figur e 4-54 . Concentration s (#/!,00 0 m 3 ) o f slende r roc k roc k megalop s a t

th e ne w combined-cycl e unit s intak e separate d b y sampl e collectio n tim e (PST) : Jun e 199 9 throug h Februar y 2000 . 

### Slende r roc k cra b megalop s wer

e predominately collecte da t th e Ocea n Nort h an dOcea n Sout h station s i n September , October , andDecembe r 199 9 (Figur

e 4-55) . They wer

e collecte da

t th e Harbo r Mout h Statio n only o

n Octobe r 14 , 199 9 durin g lo

w tide . Pea

k concentratio n (11.2/1,00 0 m 3 

### ) occurre ddurin g alo w tide a t th e Ocea n Nort h Statio n o

n Septembe

r 16 , 1999 .

E9-053. 9 4-11 6 MLPP 316(b ) Resourc e Assessmen t 4-28-200 0P.7 6 | 

# I 1 

# i i 

# I i 

# t i i 

# i i i I t i 

# i i i i 4. 0 Entrainmen t an d Source Wate r Results

Slende r Roc k

Cra b Megalop s Sourc e Wate r Mea n Concentratio n

E 8 • Hig h Tid e • Low Tid e

000 000 000 )

© £ Z W T £ZW* 0 C D £ Z W "

D £ Z (/ > T l O ) £ Z D £ Z ffi D C O £ Z Ju l 1 2 Au g 1 2 Se p 1 6 Key— KP: Kirb y Park ; D : Dairies ; HB : Harbo r Bridge ; HM : Harbo r

Mouth ; ON : Ocea n North ; OS : Ocea n Sout h O Station s no t

include din stud y desig n unti l September . © Sample s voide ddu e t o imprope r preservation . Figur e 4-55 . Sourc e wate

r concentration s (#/l,00 0 m 3 ) o f slende r rock cra b megalop s a

t si x station s nea

r Mos s Landin g Powe

r Plant : June 199 9 throug

h Februar y 2000 .

E9-053. 9 4-11 7 MLP P 316(b ) Resource Assessmen t 4-28-200 04. 0 Entrainmen t an d Source Wate r Results



## 4.1 8 Europea n Gree n Cra b Carcinus maenas 3 .7 7



# I | 

# i i t i i Carcinus maenas

Distributio n Ma p for

Gree n Crab * *Als o introducedto Sout

h Africaan

dAustralia ; distribution unknow n Photographer : McGa w Range: Native : alon g th e Atlanti c Coas t o f Europ e an d North Afric afromNorwa y t o Mauritania ; introduce d t o Sout h Africa , Australi aan d bot h coast s o f

North America . Life History: Size : male s t o 9 2 m m(3. 6 in. ) bu t

rarel y excee d 8 0 m

m(3. 1 in.) ; Fecundity : ma y spaw n twic e i n aseason , 185,00 0 eggs ; Ag e at maturity : on e t o thre e years ; Lif e span : t o five years . Habitat: A variety o f

protecte dan d semi-protecte d marin e environments , includin g rock y shores , cobbl e beaches , sand/mu dflats , an dtida l marshes ; intertidall y t o depth s o f

1 0 m(3 3 ft. ) Fishery: N o commercia l o r recreationa l fishery i n U.S . 

### Th e Europea

n gree n cra b Carcinus maenas i s a

n environmentally tolerant

specie s tha

t ha s becom e widely distribute doutside ofit s nativ e rang e following unintentiona l introductions . The specie s i s muc

h maligne doutside o

f it s nativ e rang e becaus e o

f it s voraciou s feeding habits . Th e gree n cra b i s adecapo dcrustacea

n belongin g to the Infraorde r BrachyuraandFamily Portunidae . It s nativ e rang e extend s alon g th e Atlanti c Coas t o f Europ e andNort

h Afric afro

mNorwa y t o Mauritani a(Grosholtz , 1996) . Introduce dpopulation s occu r i n Sout h Africa , Australia , and alon g bot h coast s o f Nort h Americ a(WDFW , 1999) . Th e specie s ha s bee n documente do n th e Atlanti c Coas t

o f Nort h Americ asinc e the 181 7 an dno w occur s fro

mNov aScoti at

o Virgini a (Grosholtz , 1996) . It

wa s no t foun dalon g th e Pacifi c Coas t

unti l 1989/199 0 whe

n a n establishe d populatio n was discovere di n Sa n Francisc o Bay . Gree

n cra b wer e reporte di

n Bodeg aBa

y b y E9-053. 9 4-11 8 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.7 8 

# 1

I

i 4. 0 Entrainmen t an d Source Wate r Results



### 199 3 an d ca n no w b e foundi

n ever y majo r ba y andestuar

y betwee n Monterey Ba

y an d Humbold t Ba y (Grosholtz , 1996) . They hav e bee n reporte dto occu

r a s fa r nort h a s Willap aBay , Washingto n andas fa

r sout h a s Morr o Bay , California . Th e Willap aBa y populatio n apparently di d no t persis t (Jensen , 1995) . Gree

n cra b occu r i n avariet y o f protecte dandsemi-protecte d marine environment s includin g rock y shores , cobbl e beaches , sand/mu dflats , an dtida l marshe s (WDFW , 1999 ; Grosholtz , 1996 ; Cohe n an dCarlton , 1995) . The

y ar e mos t ofte n foun di n th e intertida l an d shallo w subtida

l region s o f estuaries , typically i

n depth s o f les s tha n 6 m(2 0 ft

) (Jensen , 1995) . The

y hav e bee n collecte dto depth s o

f 1 0 m(3 3 ft

) i n Sa n Francisc o Ba

y (Cohe n an dCarlton , 1995) . On e o f th e reason s fo

r the succes s o

f the gree n cra b i s toleranc e o

f awide rang e o

f environmenta

l conditions . Adul

t gree n cra b ar e euryhalin e an

dtolerat e salinitie s fro

m4 to 5 2 ppt

(Cohe n an d Carlton , 1995) . Th e specie s i s als o eurytherma l andlive s i

n wate r temperature s rangin g fro

m5 ° t o 30 ° C (41 ° to 86 ° F ) but

ar e reporte dto tolerat

e temperature s t

o 0 ° C (32 ° F ) (WDFW , 1999) . The specie s als o achieve s reproductiv e succes s unde r awid e rang e o f environmenta

l conditions . Successfu l embryoni c developmen

t ca n occu r a t temperature s betwee

n 11 ° and25 ° C (52 ° t

o 77 ° F ) (WDFW , 1999) . Surviva l o f egg s an dlarva e i s hig h i n salinitie s rangin g fro

m2 6 t o 3 9 ppt , however , larva

l developmen

t i s inhibite di

n salinitie s o

f les s tha n 1 3 pp t (WDFW , 1999) . Becaus e ofth e species ' wide environmenta l tolerance s it

has bee n suggeste dtha

t i t ma y eventually rang e alon g th e Pacifi c Coas t fro mAlaskat

o Baj aCaliforni a(Cohe

n an dCarlton , 1995) . Th e dorsa l surfac e o f th e green cra

b carapac e i s smoot

h bu t somewha t irregular . Fiv e anterolatera

l teet h lin e the anterio r

margin o f th e carapac e o

n eac h side o f th e body . Th e teet

h ar e oriente dforwar

dandare relatively acute . Th e las t pair o f walkin g legs , although not highly modifiedfo

r swimmin g a s i n man

y othe r Portuni dcrabs , ar

e slightly flattene d(Jensen , 1995) . Gree n cra b ar e ofte n multicolore ddorsally andrang e fro madar k mottle dgreenis h to orang e (Jensen , 1995) . Yello w patche s ar e ofte n present o n th e dorsa

l surface . Coloratio n varie s individually andwit

h th e lengt h o f tim e sinc e th e las t

mol t (WDFW , 1999) . A recentl y molte d individua l i s typically dar

k mottle dgree

n in coloratio n an

dgradually turn s t o orang e and the n re da s th e intermolt

perio dprogresses . Th e ventra l coloratio n i s similarly variable . Gree n cra b ca n reach asiz e o

f 9 2 m m(3. 6 in. ) bu

t rarely excee d8 0 m

m(3. 1 in. ) (Jensen , 1995) . Male s grow faste r an dattain alarger

siz e tha n females . Individual s typically liv e fo r 3 t o 5 year s i n Californi a(Grosholtz , 1996) . Matin g i n gree n crab s occur s immediately following th e mol t o f afemale . Muc

h o f the reproductiv e informatio n availabl e o n th e specie s ha s bee

n collecte di

n it s nativ e range . Th e timin g o f matin g an dsettlement

appear s t o var y geographically . I

n th e Nort h Sea , moltin g i

n female s andsubsequent

matin g occur s betwee

n Apri l andNovember , but i s mos t common fro

m Jun e to Octobe

r (WDFW , 1999) . Along th e centra l coas t o f Maine matin g occur s fro

mJul y E9-053. 9 4-11 9 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.7 9 

# 0 8 

# s fi S 0 fi 8 0

B 4. 0 Entrainmen t an d Sourc e Wate rResult s



### through Octobe

r (WDFW , 1999) . Smalle

r female s ma

y molt andmat e earl y i n th e season and the n again i n th e fal l (WDFW , 1999) . Male s mol t i n th e Balti c Se abetween Ma y an dJune ; alon g th e centra

l coas t o f Maine , matur

e male s hav e complete dmoltin g b y Jul y (WDFW , 1999) . Egg s ar e usually extrude di

n th e spring , although ovigerou s female s ca n b e foundfro

mmid

winte r to early summe

r (WDFW , 1999) . Adul

t gree n crabs , particularl y ovigerou s females , ar e reporte dto migrat

e to deepe r wate r durin g winte

r month s (WDFW , 1999) . It i s thought tha t thes e female s ma

y move to deepe

r wate r t o reduc e variabilit

y i n environmenta

l factor s suc

h a s salinit y an dtemperatur

e (WDFW , 1999) . Femal e gree n cra b ca n produc e u

p to 185,000 egg s a

t atim e unde r favorable condition s (Cohe n an dCarlton , 1995) . Larva

e are pelagi c an

daggregat e i n the uppe r layer s o f th e wate r colum n a t nigh t durin g ebb tide . Thi s behavio r i s though t t o facilitat e dispersa l o f th e larva e into offshor

e water s wher

e growt h an ddevelopmen

t occur . Estimate s o

f the perio do

f tim e larva e spen di n offshor e water s var

y fro m2 week s to a s long a s 2 month s (a

t 15 ° C [59 ° F] ) (WDFW , 1999 ; Grosholtz , 1996) . Afte r larvae mol

t to megalopa

e the y again aggregat

e i n the surfac e water s a

t nigh t an dar e carrie dinshor

e wit h th e floo dtide . The y eventually mol

t to juvenile s an

dsettl e ou t i n th e uppe r intertida l zone . Grosholtz (1996 ) state s tha t gree n cra b recrui t durin g th e spring an

dmatur e durin g th e first

year . Othe

r source s sugges t tha t juvenile s settl e ou

t i n lat e Augus t an dmaturit y occur s durin g th e secondo r thir d yea r (WDFW , 1999) . Gree n crab s ar e highly successfu

l predator s an

dconsum e awid e variet y o f invertebrates . Th e specie s i s fast-moving andhighly dexterou s compare dto other decapo dcrustaceans . It

exhibit s learnin g capabilitie s whe

n handlin g prey , thereb y reducin g handlin g time durin g foragin g (WDFW , 1999) . Gree

n crab s hav e bee

n documente dpreyin g o

n organism s fro

mmor e tha n 15 8 generai n 10 4 familie s (Cohe

n et al. , 1995) . Analysi s o

f stomach content s include dplant s an d protist s fro m5 phyla , andanimal s fro m1 4 phyla . Dominan

t prey specie s varie da

t differen t location s bu

t include dmussels , clams , snails , polychaetes , crabs , isopods , barnacles , andalga e (Cohe n et al. , 1995) . I

n thei r nativ e range , gree

n crab s prey heavily o

n mussel s Mytilus edulis, dogwelk s Nucella lapillus, andcockle s Cerastoderma edule (WDFW , 1999) . Green cra b hav e bee n reporte dt o greatly reduc e th e abundanc e ofit s invertebrat e prey populations , includin g commercially importan

t specie s (Grosholtz , 1996) . Ther e i s grea t concer n ove r th e expansio n o

f th e gree n cra b along th e Pacifi c Coas t

o f Nort h America . Gree

n cra b predatio n o

n quahog s Mercenaria mercenaria i s though t t o hav e bee

n a facto r i n th e collaps e o

f soft-shell cla

mfisherie s alon g th e Atlanti c seaboar di n th e 1950' s (WDFW , 1999) . Th e specie s ha s als o becom e problemati c fo

r th e eas t coas t har dshell cla m Mya arenaria fisher

y (Grosholtz , 1996) . I

n California , significan

t reduction s i

n population s o

f th e smal l clam s Nutricula spp . an

dTransennella spp. , th e cumacea n Cumella vulgaris, an

d th e amphipo dCorophium spp . hav e bee n attribute dto gree

n crab s (Grosholz , 1996 ; Groshol z an d Ruiz , 1995) . The specie s ha s als o bee n documente dpreyin g o

n other cra b specie s u

p to it s ow n E9-053. 9 4-12 0 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.8 0 4. 0 Entrainmen t an d Source Wate r Result s size . Thes e includ e youn g Dungenes s cra b Cancer magister an d th e yello w shor e cra b Hemigrapsus oregonensis. Gree n crab s ar e voraciou s predator s o f youn g oyster s Crassostrea gigas an dfrequentl y recrui t int o oyste r

cultur e bag s (Grosholz , 1996) . The y ar e als o aknow n intermediat e hos t

o f a n acanthocephala n wor mProfilcollis botulus whic h ha s bee n know n t o caus e heav y mortalitie s i n seabird s (WDFW , 1999) . Ther e i s acommercia l fishery fo r gree n crab s i n Europ e wher e the y ar e use d fo r bot h foo d an d bait , however , becaus e o f thei r smal l size , n o commercia l harves t o r marketin g o f

th e specie s ha s occurre di n th e Unite dStates . Th e mos t likel y avenu e o f

it s introductio n int o Sa n Francisc o Ba y i s fro mlarva e an djuvenile s containe d in th e ballas t wate r o f larg e ships . Gree n crab s ar e als o know n t o occu r

in discarde dpackin g materia l (algae ) use d fo r seafoo d product s shippe d fro mth e Ne w Englan dcoast . Th e specie s expansio n u p an d dow n th e coas t ma y b e th e resul t

o f natura l dispersa l o f

larva e bu t

coul dals o b e fromballas t wate r o r seafoo d packin g material . 

### 4.18. 1 Europea n Gree n Cra b Carcinus maenas

Result s Europea n gree n cra b megalop s ( 3 individuals ) wer e collecte d in onl y tw o (Apri l 1 5 an d Apri l 22 , 1999 ) entrainmen t

survey s fromth e ne w combined-cycl e unit s intak e (Figur e 4-56) . Concentration s wer e 2.8/1,00 0 m 3 on Apri l 15 , 199 9 an d 1.2/1,00 0 m 3 o n Apri l 22 , 1999 . Europea n Gree n Cra b Megalop s Entrainmen t Mea n Concentratio n

8 ! 1 * 5 C 8 % o 

### I 1 0 2 

### ffffff«t«ffff**t»fcgiiff8ffif;*fFrFFF»»fr!ri?''; * ££?B»£?8S S?8 3 £ S = S:*-;g5S ? Sl8r**:sS?fS23 ? = 35i?S;; K

5 SSf e r » 5 > = = S" 8 = y3osS"sis"S*=B8* £ 28*i*i s 5 B Figur e 4-56 . Mea

n surve y concentration s (#/l,00 0 m 3 ) o f Europea n gree n cra b megalop s a

t th e Mos s Landin g Powe

r Plan t ne w combined-cycl e unit s intake : March 199 9 through Februar y 2000 .

E9-053. 9 4-12 1 MLP P 316(b ) Resource Assessmen t 4-28-200 0

## 5. 0 IMPINGEMEN T EFFECT S

Th e us e o f

ra w wate r

i n powe r plan t coolin g wate r

system s (CWS ) require s tha t objects i n th e wate r large r than th e diamete r

o f th e condense r

tube s b e screene d t o avoi d pluggin g th e condensers . Mos t

CW S intake s emplo y 3/ 8 in . (0.953 cm ) mes h travelin g screen s tha t rotat e ou t o f th e wate r t o clea r debri s an dorganism s fro mth e mesh . Coolin g wate r tha t flow s throug h th e travelin g screen s can imping e weakl y mobil e organism s agains t th e screen s o r

entangle d the min screene ddebris . Thes e organism s ar e typicall y juvenil e an d adul t fishe s an d macroinvertebrates . Th e locatio n ofth e intak e an dtravelin g screens , th e approac h velocities , an d th e quantit y o f debri s in th e wate r

ar e al l factor s that

ca n affec t impingemen t

rates . Impingemen t

studie s wer e previousl y conducte da

t MLP P in 197 9 - 1980 , an d th e result s wer e presente d i n th e Mos s Landin g Powe r

Plan t Coolin g Wate r

Intak e Structure s 316(b ) Demonstratio n (PG&E , 1983) . Mos t specie s o f

fis h hav e th e swimmin g capabilit y t o avoi d impingement . Divers , swimmin g i n front o f th e intak e a

t th e Diabl o Canyo n Powe r Plant , hav e documente d young-of-the-year rockfis h Sebastes spp. , blackey e gob y Coryphopterus nicholsi, an d othe r smal l fishe s swimmin g agains t th e curren t

jus t i n front o f th e bar rack s (Tenera , Inc. , 1998) . Othe r observations , recorde do n vide o tape , showe da1 5 c m(5.9 1 in.) painte d greenlin g Oxylebius pictus swimmin g of f o f th e travelin g scree n after apparentl y restin g ther e (Tenera , Inc. , 1998) . However , i t ha s bee n demonstrate dtha t

whe n ther e ar e larg e amount s o f detritu s (plan t

material ) i n th e intak e area , organism s stron g enoug h t o avoi d th e intak e ma y becom e trappe d i n th e detritu s an d becom e susceptibl e t o impingement (PG&E , 1982) . Th e commo n siz e scree n mes h o f 3/ 8 in . (0.95 3 cm ) i s designe d bot h t o preven t

condense r

tub e fro mpluggin g an dt o minimiz e th e approac h an d through-scree n velocitie s fo r fish protection . A s th e mes h siz e i s increase dmor e larva l an d juvenil e fish wil l ente r th e powe r

plant' s coolin g wate r syste m(b e entrained ) an dsubjecte d t o mechanical , chemical , an d therma l stresses . A reductio n i n mes h siz e o f travelin g screen s wil l increas e th e rat e o f impingemen t

an d th e stres s o f through-scree n velocities . Entanglemen t i n debri s als o increase s wit h through-screen-velocities . If ther e i s n o fish return system , thes e impingemen t effect s decreas e directl y with reduction s i n through-screen-velocities . Consisten t

wit h th e final stud y plan , impingemen t studie s ar e not

bein g conducte d a s apart o f thi s 316(b ) demonstration . Severa l ofth e modification s tha t wil l b e mad e t o th e Unit s 1 throug h 5 intak e structur e a s part o f th e modernizatio n projec t (Sectio n 2.1 ) ar e expecte d t o reduc e th e quantit y o f

debri s an dth e numbe r

o f organism s impinge d o n th e travelin g screen s a t tha t locatio n an dar e discusse dbelow . I t i s importan t

t o not e that

th e dat afro mth e prio r impingemen t

stud y showe dth e overal l rat e o f impingement

(standardize d fo r

difference s i n coolin g wate r

flow ) wa s highe r

a t th e Unit s 1 throug h 5 intak e than a t Unit s 6 an d 7 intake . Thi s E9-053. 9 5- 1 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.8 2 fy 5. 0 Impingemen t Effects

was tru e fo r

both fishes an dmacroinvertebrate s (b y afacto r o f 1. 6 fo r fishe s an d 3. 3 fo r macroinvertebrates ) (PG&E , 1983) . Th e coolin g wate r

volum e pumpe dthroug h th e Unit s 1 throug h 5 intak e structur e wil l b e reduce d fro m381,00 0 gp m(1,44 1 m 3 /min ) t o 250,00 0 gp m(94 6 m 3 /min ) fo r th e ne w combined-cycl e units . A s aresul t

o f th e lowe r

flows , approac h velocitie s wil l decreas e fro m0. 9 fee t pe r secon d (fps ; 0.2 7 meter s pe r

second[mps] ) t o 0. 5 fp s (0.1 5 mps) . Th e ne w travelin g screen s wil l b e incline da t a n approximat e angl e o f

73 ° fro mhorizonta l thu s providin g mor e surfac e scree n are a tha t wil l resul t

i n lowe r through-scree n velocities . Durin g scree n rotatio n o f th e vertica l travelin g screens , debri s ha s atendenc y t o fal l bac k int o th e wate r

a t th e air/wate r

interfac e an d creat e alarg e mass . Thes e ne w angle d screen s wil l b e mor e effectiv e a t removin g debri s than th e conventiona l vertica l travelin g screens . Th e existin g intak e tunne l i s approximatel y 35 0 f t (106. 7 m ) lon g (measure dfro mth e ba r rack s t o th e travelin g screens) . Th e ne w combine d cycl e (CC ) foreba

y intak e desig n place s th e travelin g screen s approximatel y 1 0 feet (3. 1 m ) behin d th e bar racks . Th e shortenin g o f th e tunne l ma y hel p t o reduc e impingement o f schoolin g fishe s that can becom e trappe din th e tunne l an d subsequentl y impinged. Dat apresente di n thi s sectio n ar e fromimpingemen t studie s conducte d a

t th e Mos s Landin g Powe r Plan t in 197 9 - 198 0 a s part

o f th e first 316(b ) Demonstratio n progra m(PG&E , 1983) . Dat areporte di n PG& E (1983 ) wer e presente d a s number s o f organism s caugh t

durin g eac h impingemen t

collection . W e hav e obtaine d th e actua l coolin g wate r volume s fo r

Unit s 1 throug h 5 an dUnit s 6 an d7 fo r th e perio d o f

th e impingement

stud y an d hav e calculate d densitie s o f

th e mos t abundantl y impinge d fishe s an d Cancer spp . crabs . Th e 198 3 evaluatio n foun dtha t th e powe r

plan t wa s employin g BT A intak e technology . Th e evaluatio n indicate dtha t

th e existin g coolin g wate r intak e syste mimpinge s smal l number s o f adul t fishe s an dinvertebrate s o n th e intak e screens . 

## 5. 1 Impingemen t Stud y Th e impingement

stud y (PG&E , 1983 ) wa s designe d t o quantif y th e compositio n an d abundanc e o f impinge dorganism s at

both Unit s 1 throug h 5 an d Unit s 6 an d 7 o f th e MLPP . Length s an d weight s o f

al l fishe s an dselecte dmacroinvertebrate s impinge d in 24-hou r period s wer e recorded . Seasona l an ddie l (day an dnight ) pattern s o f impingemen t

wer e determine d graphically . 

### 5.1.1 Methods Impinge dfishe s an dmacroinvertebrate s wer e collecte d fro mweekl y sample s at th e intake s o f both Unit s 1 throug h 5 an dUnit s 6 an d 7 . Th e impingement stud y bega n o n Januar y 20,197 9 E9-053. 9 5-2 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.8 3 5. 0 Impingemen t Effects 

### an d continue dthrough Marc

h 18 , 1980 . Sample s wer

e take n ove r a24-hou r perio dtha

t wa s divide dinto either

3

- o r 6 - hou r cycles . Thi s cycle-breakdow n o f sampl e collectio n allowe d fo r the determinatio n ofth e diel distributio n ofth e impinge dorganisms . Befor e eac h samplin g perio dal

l th e travelin g screen s wer

e rotate dan

drinsed to remov e previously impinge dorganism s an ddebris . The screen s remaine dstationar y fo r 2.7 5 hour s an

d the n wer e rotate dfo

r 1 5 minute s while impingedorganism s wer e rinsed into acollectio n baske t lined wit h '/i-inch (0.63 5 cm) steel mesh . Thi s procedur e wa s repeate dfo

r th e entir e 24-hou r sampling period . Th e impinge dorganism s wer

e removedfro

mthe detritus . Fishe s an

dmacroinvertebrate s wer

e identified t

o species , counted , an

dmeasured . Th

e for k lengt h (tip o f snou t to for k i n tail ) o f th e fishe s was measure dfo

r u p t o 5 0 individual s o

f eac h species , carapac e width s measure dfo r Cance r spp . an dth e mantl e lengt

h was recorde dfo

r squid s an doctopu s i

n ever y 24-hou r collection . Gonad s o f th e mos t commonl y impinge dfish wer

e periodically examine dto asses s spawning condition . Gonad s wer

e dissecte dfro

mth e fish an

dclassifie da s undeveloped , developing , mature , o r spent . Al l sample s wer

e subjecte dt

o aQualit y Contro l progra

mtha t calle dfo r resortin g sampl e debri s an dreidentificatio n o

f th e collecte dorganisms . Samplin g efficiency wa s als o teste di n variou s experiments . Markeddea

dfish wer e release ddirectly i

n fron t o f th e intake s andth e numbe r o f recovere dfishe s wa s recorded . Eighty-seven percen t o f the dea dfish release dinto the Unit s 1 throug h 5 intak e wer e recovere di

n thi s tes t o f samplin g efficiency but

only 3 5 percent

wer e recovere dfro

mUnit s 6 and7 . Th e lo

w recover y rat e fo r Unit s 6 an

d7 wa s attribute dt

o a travelin g scree

n desig n tha

t was built t o remove jellyfish , kelp , an dalgae . Thi s systemconsist s o f L-shape d bracket s or

cylindrica l projection s attache dto th e travelin g screens . Thes e bracket s interfere d wit

h the effectivenes s ofth e spraywash syste man dsom e ofth e impinge dmateria

l was carrie dove

r an dbypasse dthe secondar

y sluiceway . It

was observe dtha

t thi s "carry-over " occurre d whe

n ther e wa s insufficien

t wate r pressure . The differentia

l collectio n efficiencie s betwee n the tw o intake s wer

e take n int o consideratio n whe

n impingemen

t characteristic s wer

e compared .

E9-053. 9 5- 3 MLP P 316(b ) Resource Assessmen t 4-28-200 05. 0 Impingemen t Effect s



## 5. 2 Lif e Historie s o f Abundantl y Impinge d Fishe s 5.2.1 Fishes Norther n anchovy Engraulis mordax was th e most

abundan t fish specie s collecte dfro

mbot h intake s an d constitute d6 1 percen

t o f al l fishe s impinged . Shine

r perch Cymatogaster

aggregata ranke dsecondin abundanc e a t 9 percent , followedby topsmelt Atherinops affinis ( 9 percent) an d Pacifi c herrin g Clupea pallasi ( 4 percent) . Thes e fou

r specie s accounte dfo

r 8 3 percen t o f all fishe s impinge ddurin g th

e entir e study . Lif

e historie s fo

r thes e species , excep t

Pacifi c herrin g (discusse d previously i

n Section 4.10) , ar

e presente dbelow . Norther n Anchov y Engraulis mordax

Photographer: Mark Conlin 

### Th e norther

n anchovy Engraulis mordax i s aclupeoi dfish (anchovy , sardine , andherring ) belongin g t

o th e famil y Engraulidida

e (th e anchovies) . Engraulidida e contain s 13 9 specie s o

f anchovie s tha

t occu r throughou

t the worl d(Moyl e an

dCech , 1988) . Member s o f th e famil y ca n b e distinguishe dfro

mothe r clupeid s by their

overhangin g snou

t an dlon g uppe

r ja w (Moyl e an

d Cech , 1988) . Norther

n anchovy , one d

f th e most prolifi c fishe s i

n the coasta

l water s o f the Pacific , contribut

e significantly t

o the economic s ofth e world' s fisheries. Th e norther

n anchov y populatio n ha s bee

n separate dint

o thre e distinc t

sub-populations , based o n morphologica

l differences , an

dar e represente dgeographically b y th e northern , central , an d souther n sub-population s (PFMC , 1990 ; Love , 1996) . Th e norther n sub-populatio n i s foun

d fro mVancouve

r Island , Britis h Columbi at

o centra l California . The distributio n o f th e centra l sub-populatio n extend s fro

mcentra l Californi at

o norther n Baj aCaliforni aan

dth e souther

n populatio n i s foun

dalong the souther

n coas t o f Baja . Considerabl e fluctuation s i n anchov y population s occu

r i n respons e t

o cycli c variation s i

n oceanographi c condition s (Moyl e an d Cech , 1988) . E9-053. 9 5- 4 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.8 5 

# 1 1 1 1 1 1 1

i 1 1 1 5. 0 Impingemen t Effect s

Norther n anchov y ar e apelagi c marin e specie s tha t occur s fro msurfac e water s dow n t o depth s o f 30 5 m(1,00 0 ft) (Love , 1996) . The y ca n b e foun d i n dens e school s withi n bay s an d estuaries , an d i n ocea n water s fro mjus t outsid e th e surf

zon e t o mor e than 30 0 mile s offshor e (Love , 1996) . The y ar e mos t

commo n withi n 10 0 mile s o f lan d (Love , 1996) . Anchovie s mak e extensiv e seasona l movement s u p an d dow n th e coast , a s wel l a s offshor e an d inshor e (Love , 1996) . Thei r

patter n o f

seasona l movemen t

i s moderatel y predictable , at best . School s generall y dispers e an dmov e towar dth e surfac e water s aroun d sunse t t o feed . The y re-formint o larger , mor e consolidate dschool s late r i n th e nigh t

(Love , 1996) . Norther n anchov y ar e elongat e fishe s wit h blu e o r gree n back s an d silve r

bellies . The y hav e bee n reporte dt o reac h asiz e o f 22 9 m m( 9 in. ) bu t

rarel y excee d 17 8 m

m(7in. ) (Mille r

an d Lea , 1972 ; Love , 1996) . Norther n anchov y ma y liv e t o 7 years , bu t mos t d o no t liv e pas t 5 year s o f age . Ther e ar e geographi c difference s betwee n th e tim e whe n individual s becom e reproductivel y mature . Whil e al l anchov y ar e matur e b y th e tim e the y reac h 4 year s in age , som e may matur e withi n thei r

firs t year in th e southern part s o f

thei r rang e (Love , 1996) . Spawnin g occur s throughou t th e year (wit h peak s in Decembe r

throug h May ) i n th e souther n en d o f th e norther n anchovy' s range , bu t i s seasona l in th e northern locations . Nea r th e Columbi a River , of f o f th e coas t o f Washingto n an d Oregon , th e fish spaw n fro mmid-Jun e throug h mid

August . Mos t

spawnin g occur s withi n 15 0 mile s fro mshor e an d typicall y takes plac e at night . Female s ar e oviparou s an dcan spaw n 2 t o 3 time s ayear , releasin g fro m2,70 0 tol6,00 0 egg s pe r batc h (Brewer , 1978) . Lov e (1996 ) indicate s that female s can releas e fro m2,70 0 t o 16,00 0 egg s pe r batch , with annua l fecundit y a s hig h a s 130,00 0 egg s in souther n California . Th e numbe r o f egg s produce dvarie s geographically . Egg s ar e pelagi c an d ar e broadcas t int o th e wate r

colum n (Bolin , 1936 ; Wang , 1986) . Th e egg s hatc h i n 2 t o 4 day s an d larva e begi n thei r pelagi c phas e a

t approximatel y 3 m mT L (Wang , 1986 ; Love , 1996) . Th e larva l phas e last s for approximatel y 7 0 day s (Wang , 1986 ; Love , 1996) . Larva e begi n schoolin g at 1 1 t o 1 2 mm(0.4 3 t o 0.4 7 in. ) an d transformint o juvenile s a t 3 5 t o 4 0 m m(1.3 8 t o 1.5 7 in. ) (Hart , 1973) . Surviva l o f juvenile s i s though t t o b e greates t

durin g cal mocea n condition s (Love , 1996) . Norther n anchov y ar e primar y consumer s an d filter-feed o n plankton . The y fee d o n zooplankto n suc h a s krill , copepods , an darro w worms , an d o n phytoplankton , smal l fishes , an d pelagi c fish egg s (Love , 1996) . Anchov y ar e undoubtedl y on e o f th e majo r

forag e fishe s withi n thei r range . Marin e mammals , se abirds , fishes, an d invertebrate s al l pre y on anchov y at som e stag e o f

thei r life . Norther n anchov y i n th e centra l sub-populatio n ar e harveste d commerciall y in Mexic o an d Califomi afo r

reduction , huma n consumption , liv e bait , dea d bait , an d othe r non-reductio n commercia l use s (PFMC , 1998) . Landing s o f norther n anchov y in Californi abetwee n 191 6 an d 199 7 varie dfro malo w o f 7 2 metri c ton s (MT ) in 192 6 t o ahig h o f 143,79 9 M T i n 197 5 E9-053. 9 5-5 MLP P 316(b ) Resource Assessmen t 4-28-200 05. 0 Impingemen t Effects



### (PFMC , 1998) . Thi s historica l variatio n i

n landing s generally reflect s change s i n bot h anchov y population s an

dth e interes t

o f fisherman t

o fish fo r them . Th e mos t

recen t stock assessmen

t fo r norther n anchov y estimate dspawnin g biomas s a t 388,00 0 MT durin g the middl e o f Februar y 199 5 (Jacobson et

al. , 1995) . Although n o mor e recen t stoc k assessment s hav e bee

n made , a qualitativ e analysi s o

f the availabl e dataindicate s tha t thi s remain s th e bes t

estimate o

f curren t spawning biomas s (Jacobso n e t al. , 1997) . Shine r perc h Cymatogaster aggregata 

### Shine r perc h Cymatogaster

aggregata belon g t o th e smal l (2 3 species ) famil

y Embiotocida

e whic h ar e foun dabundantly i

n sub-tropica

l an dtemperat e water s along th e Pacifi c coas t o f Nort h Americ aan

dAsi a(Moyl e an

dCech , 1988) . Shine

r perc h rang e fro

mSa n Quintin Bay , Baj a Califomi at

o Por t Wrangell , Alask

a(Mille r an dLea , 1972) . The

y ar e abundan t fro mBritis h Columbi asout

h (Love , 1996) . Shine

r perch an dstripe dsurfperc

h Embiotoca lateralis ar

e th e tw o mos t widel y distribute dembiotoci dspecie s (Odenweller , 1975) . Shine r perc h inhabit awid e variet y o f habitat s includin g estuarie s an dquiet bays , eelgras s bed s Zostera marina, andope

n coas t area s aroundkel

p beds . The

y ar e als o frequentl

y foun di n the vicinit y o f piers , jetties , andoil platforms . Shine r perc h occu r commonl y i n school s an

d aggregation s fro

mth e intertida

l zon e dow

n t o depth s 6 1 m(20 0 ft

) (Love , 1996) . The

y ar e mos t ofte n foun di n depth s o f les s tha n 1 5 m(5 0 ft

) but hav e bee n collecte da s deep a s 21 0 m(69 0 ft ) (Love , 1996) . They ar

e euryhalin e an

dca n als o b e foun

di n lowe r salinit y area s o f coasta l stream s andeve

n occasionall y i

n freshwate

r (Fierstin e e

t al. , 1973 ; Love , 1996) . The y ar e als o reporte d t o b e eurytherma

l an dliv e i n wate r rangin g fro

m4 ° C to 21 ° C (39 ° F to 70 ° F ) (Odenweller , 1975 ; Love , 1996) . Shine r perc h ar e small fishes tha

t ar e silver y i n overall appearanc e but

hav e black

spot s o n their scales . Th e black

spot s for mabackgroun dpatter

n o f thin horizonta

l stripe s alon g th e side s o

f the fish (Humann , 1996 ; Love , 1996) . There ar e severa l (usuall y 3 ) vertica

l yello w bar s overlai d o n th e patter

n alon g th e mid-bod

y (Humann , 1996 ; Love , 1996) . Ther e i s ofte n adusk y patch o n the snou t below th e nostri l (Humann , 1996 ; Love , 1996) . Shine r perch reach asiz e o

f 17 8 m m (7in. ) andma

y liv e fo r 8 year s (Love , 1996) . The y becom e reproductively matur

e afte r 1 yea r (Love , 1996) . Spawning i

n shine r perch occur s durin g th e sprin g an dsummer . Odenwelle

r (1975 ) relate d th e timin g o f spawnin g t

o the temperatur

e an dproductivit

y o f the environment . I

n the souther

n portion s o f it s rang e spawnin g begin s i n April-May , whil e i

n Britis h Columbi ait

begin s i n June

August . Female s ar

e ovoviviparou s an

dyoung ar

e bomdurin g the winte

r months . Female s stor e sper mfo r aperio do f tim e befor e embry o developmen

t begins . Thirty-si x embryo s ma y develop i n asingl e female (Love , 1996) . Becaus e o f their greatly enlarge dandhighly E9-053. 9 5- 6 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.8 7

!



# 1 B 

# 1 1 1 1 1 1 1 1 i I 5. 0 Impingemen t Effects



### vascularize ddorsal , pelvic , andana l fins, embryo s ar

e abl e to obtai n nutrient s fro mth e mothe

r (anddevelop ) in uterus-lik

e sac s within th e ovary . Whe n bo mthey ma

y b e greater

tha n 3 c mi n lengt h (Moyl e andCech , 1988) . Shine r perch fee dprimarily on planktoni c organism s suc h a s copepods , amphipods , arro w worm s an dfish egg s (Love , 1996) . Whe n zooplankto n abundanc e i s lo w the y will feedheavil y o

n

. benthi c organism s suc

h a s pelecypods , gastropods , polychaetes , tunicates , andfish egg s (Odenweller , 1975) . Shine r perch ar e preyedupo

n by awid e variet y o f marine mammals , birds , andfishes . Oxma n (1995 ) determine dtha

t shine r perc h composed2.8 7 percen

t ofth e prey item s consume db y harbo r seal s Phoca vituUna i

n th e Mos s Landing/Elkhor

mSloug h area . Californi ase alion s Zalophus californianus ar e als o reporte dt o fee

do n shine r perch (Love , 1996) . They hav e a variet y o f avia n predator s including : grea t blu e heron s Ardea herodias, wester n gull s Larus occidentalis, bal deagle s Haliaeetus leucocephalus, leas t tem s Sterna antillarum an dBrandt' s Phalacrocorax

penicillatus an

ddouble-creste dcormorant s Phalacrocorax auritus (Love , 1996) . Shine r perc h ar e als o consume db

y anumbe r o f piscivorou s fishes . Califomi ahalibut Paralichthys californicus, kelp bas s Paralabrax clathratus, andbarre dsandbas s Paralabrax nebulifer ar e among their

man y piscin e predator s (Love , 1996) . Although small landing s ar e made , shine

r perch hav e littl e commercia l value . The

y ar e caugh t by recreationa

l angler s i n bay s an dfro mpier s an

dar e considere dagoodbaitfis h fo r anumbe r o f gamefish . Topsmel t Atherinops

affinis 

### Topsmelt , along wit

h jacksmel t

an dgrunion , belong t

o th e famil y Atherinidae (silversides) . Thes e schoolin g fish ar

e foun dfro mthe Gul f o f Californi ato Vancouve

r Island , Britis h Columbi a(Mille

r an dLea , 1972) , occasionally extendin g a s fa r nort h a s Queen Charlotte Islands , Britis h Columbi a(Humann , 1996) . The y ar e mos t commonly foundfro

mTillamook Bay , Oregon southwar

dandare ver

y abundan t i n Californi awater s (Love , 1996) . Topsmelt usually aggregat

e i n shallo w water s an

dtendt o schoo l nea

r th e surface , although the

y ma y b e see n as dee p a s 9 m(3 0 ft)(Love , 1996) . Topsmelt ar e ofte n th e mos t

abundan t fishes i n estuaries . The

y ar e als o foun

di n kel p canopies , along sand

y beaches , anda

t times , offshore . The Sa n Francisc o topsmelt

{Atherinops affinis affinis), i s distinctiv e becaus e i t i s th e only one o

f th e thre e subspecie s i

n thi s rang e t

o b e foun di n the Sacramento-Sa

n Joaqui n estuary . Topsmelt commonl y liv e i n the salt pond s nea

r the souther

n endo f Sa n Francisc o Bay , withstandin g salinit y concentration s thre e time s greate r tha n tha t o f ocea n water . Topsmel t

are tolerant

t o a wid e rang e o f salinities , as they als o live i n fres h an dbrackis h wate

r (Carpelan , 1955) .

E9-053. 9 5- 7 MLP P 316(b ) Resourc e Assessmen t 4-28-200 05. 0 Impingemen t Effects



### Topsmelt ar e silver y gree n along thei

r back s wit h asilve r strip e midlin e alon g thei r

side . The y ca n reach u p t o 36 8 m m(14. 5 in. ) (Love , 1996) an dma y liv e si x to nin e year s (Wang , 1996) . Thes e fishe s matur

e betwee n tw o an dthre e year s o

f ag e (Love , 1996 ) although Carpela n (1955 ) reporte dtha

t the topsmelt

o f th e sal t pond s nea r Alvis o spawne dwhe

n they wer

e one yea r old . Topsmelt spaw n along the Pacific coas t

an di n estuaries . I

n Sa n Francisc o Bay , spawnin g generally occur s betwee

n Apri l an dOctober , wit

h apea k i n Ma y andJun e (Wang , 1996) . Female s probably spaw

n mor e tha n onc e (Wang , 1986 ) an

dproduc e betwee

n 20 0 to 1,00

0 egg s pe r season (Love , 1996) . Spawning take s plac e primarily a t night . Topsmelt

egg s for mlarg e cluster s a s they becom

e entangle di

n the variet

y o f marine plant s useda s spawnin g substrate . Topsmelt larva e o f the estuarie s tendto swi

mi n school s nea

r th e surfac e of

shallo w andope

n water , wherea s pelagi c larva e along the coas t

remai n i n the top fe

w inche s ofth e kelp canopies . Topsmelt fee do n plankton , algae , crustaceans , detritus , amphipods , an dinsec t larvae . Thi s specie s i s targete db

y Californi asealions , harbo r seals , leas t

tems , an dBrandt' s anddouble

creste dcormorants . Topsmel t ar e als o use da s foo dan dbait (Love , 1996) . Bocacci o Sebastes

paucispinis 

### Bocacci o ar

e on e o f the most wide-rangin g an

dcommercially importan

t rockfis h species . They belon g t o th e famil y Scorpaenida

e tha t i s composedrockfishe s an dscorpionfishe s an

di s represente dby mor

e tha n 31 0 specie s worldwid

e (Moyle andCech , 1988) . Bocacci o ar e one o f th e mor e tha n 6 0 specie s i

n th e genu s Sebastes tha

t occu r of f the Pacifi c Coas t

o f Nort h Americ a (Moyl e an d Cech , 1988) . The rang e o f bocacci o extend s fro

mStepova

k Bay , Alaska

n Peninsul a to Pt . Blanca , Baj aCaliforni a(Mille r an dLea , 1972 ; Love , 1996) . They ar e mos t abundan t fro m Britis h Columbi aandsouther n Alask ato centra l Baj aCaliforni a(Love , 1996) . Bocacci o ofte n for mlarg e aggregation s an

dtendt o occu r nea r th e bottom . Though generally associate dwit h har dbenthi c substrates , the

y ma y b e foun dove r mu dan dsandbottom s o r

hig h in the wate

r colum n (Love , 1996) . Bocacci o occu r fro mth e surfac e dow

n t o depth s exceedin g 45 7 m (1,50 0 ft) . Adul

t bocacci o ar

e generally foun

di n deeper , offshor

e water s an

dar e mos t common i n depth s fro

m4 6 m(15 0 ft

) t o 30 5 m(1,00 0 ft

) (Love , 1996) . Juvenile s ma y b e foun di n surfac e water s unde

r drifting mat s o

f kel p o r aroundinshor

e reef s an dkelp bed s (Love , 1996) . Hug e aggregation s ofjuvenil e bocacci o invade shallo w nearshor e water s durin g certai n years . Bocacci o gravitat

e int o deepe r wate r a s they gro

w an dar e though t to mov e abou

t extensivel y a s adults . Tagge djuvenile s have bee n recapture d6 0 an

d8 0 mile s fro

mthei r releas e sit e (Love , 1986) . Bocacci o are a

n elongate , moderatel

y compresse dspecie s o

f rockfis h wit

h asquar e to slightl y indente d tail . The

y ar e readily distinguishe dfro

mothe r rockfish specie s o

f simila r bod y shap e b y their coloratio n an

dlarg e mouth , i

n whic h th e maxillar y extend s beyondthe rea

r margin o f E9-053. 9 5- 8 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.8 9 

# 1 I 1

m 

# I 1 1 1 1 1 I fll 

# I 5. 0 Impingemen t Effect s

th e ey e orbit , whil e i n chilipepper s Sebastes goodei an d silvergra y rockfis h Sebastes brevispinis th e maxillar y onl y extend s t o th e middl e o r rea r o f th e orbit . Th e lowe r

ja w o f bocacci o project s upward , endin g wit

h aprominen t

symphysea l knob . Adult s ar e adark , rusty-brow n t o gra y colo r dorsally , gradatin g t o asilver y belly . Ther e i s scattere d spottin g o n th e bac k an d side s o f juvenile s an dmos t

adults . In adults , th e spottin g i s largel y confine d t o area s abov e th e prominen t

latera l line . Chilipepper s an d silvergra y rockfis h d o no t hav e spotting . Melanisti c (black ) blotche s ar e als o presen t o n asmal l proportio n ofth e adul t bocacci o population . Th e size , shape , location , an d numbe r o f thes e blotche s varie s wit h affecte d individuals . Melanisti c blotche s occu r

o n severa l othe r

schooling , deepwate r

rockfis h species . Bocacci o ar e ovoviviparou s o r primitivel y viviparou s wit h fertilizatio n an d embryoni c developmen t

takin g plac e withi n th e bod y prio r t o larval extrusio n (Phillips , 1964 ; Love , 1996) . Fecundit y varie s proportionatel y wit h th e siz e o f

th e female . A 38 1 m m(1 5 in. ) fis h may produc e 20,00 0 egg s pe r

seaso n whil e a76 2 m

m(3 0 in.) fis h can produc e man y a s 2. 3 millio n egg s in aseaso n (Phillips , 1964 ; Love , 1996) . Whe n embryoni c developmen t i s complet e a femal e extrude s he r

"eyed " larva e int o th e surroundin g water , whic h activate s the m(Morris , 1956 ; Phillips , 1964) . Larva e rang e from3. 7 m m(0.1 5 in. ) t o 5. 4 mm(0.2 1 in.) i n lengt h a t extrusion . Spawnin g seaso n varie s somewha t wit h latitude . I n southern Californi aspawnin g peak s i n Januar y bu t

ma y occu r

i n durin g mos t

othe r month s o f

th e yea r (Octobe r throug h July ) (Love , 1996) . In centra l an dnorthern Californi aspawnin g occur s fro mJanuar y t o Ma y an d peak s i n Februar y (Love , 1996) . Furthe r north spawnin g take s plac e fro mJanuar y throug h Marc h (Love , 1996) . Larva l bocacci o ar e pelagi c planktivore s an d typicall y occu r i n th e to p 10 0 feet o f th e wate r

colum n (Thomas an d Bence , 1992) . The y ar e widel y distribute d ove r th e continenta l shel f

an dhav e bee n collecte d i n plankto n net s a s fa r a s 30 0 mile s offshor e (Thoma s an dBence , 1992 ; Love , 1996) . Whe n larva e reac h asiz e o f 3 8 t o 6 4 m m(1. 5 t o 2. 5 in.) the y begi n settl e out

o f th e wate r

colum n an d orien t

t o botto msubstrate s (Thoma s an d Bence , 1992) . Settlement

generall y occur s b y lat e Ma y o r earl y Jun e (Thomas an d Bence , 1992) . Bocacci o ar e relativel y larg e rockfishe s at adulthoo d an d gro w rapidl y compare d t o man y ofth e deepwate r

rockfis h species . Bocacci o gro w t o ove r 91 0 m m(3 6 in.) reachin g aweigh t o f 1 5 pound s (Thoma s an dBence , 1992 ; Love , 1996) . The y liv e for a t leas t 3 5 year s an d possibl y a s lon g a s 4 0 (A . Andrew s MLM L pers . comm.) . At 8 t o 1 0 year s o f

ag e abocacci o i s aroun d 61 0 m m(2 4 in. ) in lengt

h an dmay weig h 2. 3 k g ( 5 lbs ) (Thoma s an d Bence , 1992 ; Love , 1996) . Female s gro w significantl y faste r than male s an d ar e large r whe n the y matur e (Phillips , 1964 ; Love , 1996) . Female s ar e als o though t t o hav e alonge r

lifespan (Love , 1996) . Siz e a t maturit y varie s geographically , wit h individual s in souther n Californi amaturin g betwee n 35 6 an d 45 7 m m(1 4 t o 1 8 in. ) an dindividual s t o th e north maturin g betwee n 55 9 an d 61 0 m m(2 2 t o 2 4 in. ) (Love , 1996) . E9-053. 9 5- 9 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.9 0 

# i I 

# 1 1 

# 1

1

! 

# 1 1 1 5. 0 Impingemen t Effect s

Th e rapi dgrowth o f

youn g bocacci o i s fuele d b y thei r die t o f smal l fishes . Othe r

youn g rockfis h Sebastes spp. , surfperc h (Famil y Embiotocidae) , jac k mackere l Trachurus symmetricus, an d a variet y o f smal l inshor e fishe s compos e th e bul k o f thei r die t b y th e en d o f

thei r first year (Phillips , 1964) . A s bocacci o gro w an d mov e t o deepe r wate r the y continu e t o pre y primaril y on fishes , however , the y wil l als o consum e invertebrat e specie s suc h a s marke t squi d Loligo opalescens an dpelagi c re dcrab s Pleuroncodes planipes. Smal l rockfishe s Sebastes spp. , sablefis h Anoplopoma fimbria, northern anchovie s Engraulis mordax, an d lanternfis h (Famil y Myctophidae ) ar e amon g th e fishe s frequentl y consume d b y adul t bocacci o (Phillips , 1964 ; Love , 1996) . Pinniped s suc h a s harbo r seal s Phoca vituUna an d norther n elephan t seal s Mirounga angustirostris are amon g th e predator s o f bocacci o (Love , 1996) . Juvenile s als o fall pre y t o avariety o f

seabirds . Historicall y bocacci o hav e bee n amajo r componen t

of commercia l rockfis h landing s i n California . I

n additio n t o bein g th e dominant rockfis h specie s i

n California' s earl y longlin e fishery , i t wa s th e mos t

abundan t rockfis h harveste d i

n th e otte r

traw l fishery fro mMorr o Bay t o Fort Brag g unti l th e mid-1980 s (Thoma s an d Bence , 1992) . Bocacci o hav e als o bee n a prominen t

specie s i n se t gillne t an dhoo k an d lin e rockfis h fisheries . Sinc e th e mid-1980 s chilipeppe r

hav e replace dbocacci o a s th e dominan t rockfis h specie s i n th e traw l fishery (Thoma s an d Bence , 1992) . Federa l managemen t o f bocacci o bega n i n 198 2 an d becaus e o f it s continue d declin e i n abundanc e a

n annua l harves t

guidelin e o f

4 millio n pound s was establishe d fo r th e specie s i n 199 1 (Thomas an dBence , 1992) . Biomas s estimate s for th e specie s fel l fro m 15 0 millio n pound s i n 197 8 t o 2 0 millio n pound s i n 198 9 (Thoma s an d Bence , 1992) . Landing s o f bocacci o hav e continue dt o declin e i n th e 1990 s an d quota s hav e becom e increasingl y restrictive . Decline s i n landing s can b e th e resul t o f anumbe r

o f factor s includin g th e species ' abundance , mor e restrictiv e quotas , an d marke t forces . Commercia l bocacci o landing s i n Californi awer e firs t accuratel y estimate d i n 197 8 whe n the y average daroun d4 millio n pound s annuall y (Thoma s an d Bence , 1992) . Accurat e landin g dat a fo r bocacci o ar e no t

availabl e fro m1981-199 0 (i n CDF G Landin g Summary ) becaus e th e majority o f

bocacci o wer e lande di n acombine d bocaccio/chilipeppe r marke t categor y (Figur e 5- 1 an d Figur e 5-2) . Fro mavailabl e CDF G data , landing s o f bocacci o peake d a

t ove r 1 0 millio n pound s b y 198 0 an dthe n bega n aslo w bu t stead y declin e unti l 199 0 whe n landing s wer e agai n abou t 4 millio n pound s (CDF G Landin g Summary) . Beginnin g i n 1991 , whe n aquot afo r th e specie s was established , landing s decline d fro move r 2 millio n pound s (i n 1991 , 1992 , an d 1993 ) t o les s tha n 300,00 0 pound s i n 199 8 (Figur e 5-3) . Th e ex-vesse l pric e fo r bocacci o sinc e 198 6 ha s average d3 9 cents apoun dan drange d fro malo w o f les s than 3 3 cent s i n 198 6 t o ahig h o f aroun d5 0 cent s i n 199 8 (CDFG) . Virtuall y al l bocacci o ar e processe d (filleted ) an d sol d fres h a s roc k co do r re dsnappe r

fillets.

E9-053. 9 5-1 0 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.9 1

5. 0 Impingemen t Effect s

600,00 0 500,00 0 400,00 0

• o § 300,00 0 o 0 . 200,00 0 100,00 0 I Montere y I Moss Landin g 3 Sant a Cru z

1986 198 7 198 8 198 9 199 0 199 1 199 2 199 3 199 4 1995 199 6 199 7 199 8 Yea r Figur e 5-1 . Bocacci o landing s fro mMontere y Bay ports . Include s marke t categor y 25 3 (bocaccio) . 2,500,00 0 2,000,00 0

c n • O c 3 O Q . 1,500,00 0 1,000,00 0 500,00 0 I Montere y I Mos s Landin g I Santa Cru z

198 6 198 7 198 8 198 9 199 0 199 1 199 2 199 3 199 4 199 5 199 6 199 7 199 8 Yea r Source: CDFG

Landing Summaries 1986-1998. Figur e 5-2 . Landing s o f combine d marke t

categor y for

bocaccio/chilipepper . Include s marke t categor y 95 6 (bocaccio/chilipepper) .

E9-053. 9 5-1 1 MLP P 316(b ) Resourc e Assessmen t 4-28-200 05. 0 Impingemen t Effect s P.9 2

12,000,00 0 - | 10,000,00 0 • 8,000,00 0 c o § 6,000,00 0 o 0 . 4,000,00 0 2,000,00 0 I Bocacci o I Bocaccb/Chilipeppe r

j? > cS > o P <&&c&<&&c&<&<$>cX> d p dfi d ? d p d p d p d ? Yea r N <S P N < ^ N «S P N S P N cJ P N cj P N cj P N c* p ,£ P N cs p g> N c ^ N c ^ ^ ^ jp ^ $> $

Source: CDFGLanding Summaries 1986-1998. 

### Figur e 5-3 . Bocacci

o landing s fro

mCaliforni aincludin g th e combine dcategor y fo r bocacci o an d chilipepper . Bocacci o ar

e als o a n importan

t specie s i n recreationa

l catche s along th e coas t

o f Californi aan

d Oregon (Love , 1996) . A majorit y o f part y boa t landing s o

f th e specie s occu

r fro mMendocin o County , norther

n Californi at o souther

n Californi a(Love , 1996) . I n souther n Californi a bocacci o ma

y accoun t fo r a s muc h as 1 4 percen

t o f the tota l recreationa

l catch (Thoma s an

d Bence , 1992 ; Love , 1996) . The y ar e generall y caugh t i n greate r abundanc e i

n the souther

n Californi afisher

y tha n i n th e norther

n Californi afisher

y (Thoma s andBence , 1992 ; Love , 1996) . Recreationa

l catche s o f bocacci o b y the part

y boa t flee t ar e typically mad

e i n depth s o f 7 6 m (25 0 ft ) t o 22 9 m(75 0 ft

) o f wate r (Thoma s an

dBence , 1992) . Sinc e 198 4 recreationa

l landing s ofth e specie s hav e followedth e sam e trendas commercia

l landing s (Thoma s andBence , 1992) . Beginnin g i

n 199 9 th e recreationa

l tak e o f bocacci o was restricte dto 3 fish pe r day . Pacifi c herrin g Clupea pallasi 

### Th e lif e histor y ofth e Pacifi c herrin g i s discusse di n Section 4.1 0 o

f thi s report . 

### 5.2.2 Macroinvertebrates A majorit y (6 2 percent) o

f the tota l macroinvertebrate s impinge dby bot h MLP P intake s wa s collecte d fro

mUnit s 1 throug

h 5 . Cancer

spp . crab s constitute d3 7 percen t o f the tota l numbe r o f macroinvertebrate s impingeda t Unit s 1 throug

h 5 an d9 percen t a t Unit s 6 an

d7 . Crangon spp . shrimp s constitute d1 9 percen t o f th e tota l numbe r impinge da

t Unit s 1 through 5 an

d 3 1

E9-053. 9 5-1 2 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.9 3 5. 0 Impingemen t Effects 

### percen t a t Unit s 6 and7 . The specie s compositio n o f impinge dorganism s wa s generally simila r betwee n th e tw o intakes . Roc k Crab s Family

Cancridae 

### Th e lif e histor y ofth e rock

cra b i s discusse di

n Section 4.1 1 o

f thi s 316(b ) Demonstratio n Report . Hair y Roc k Cra b Cancer

jordani 

### Th e lif e histor y o f the hair y roc k cra b i s discusse di

n Section 4.1 2 o

f thi s 316(b ) Demonstratio n Report . YellowRoc k

Cra b Cancer

anthonyi 

### Th e lif e histor y ofth e yello w roc

k cra b i s discusse di

n Section 4.1 3 o

f thi s 316(b ) Demonstratio n Report . Brow n Roc k

Cra b Cancer

antennarius 

### Th e lif e histor y o f th e brown roc

k cra b i s discusse di

n Section 4.1 4 o

f thi s 316(b ) Demonstratio n Report . Dungenes s Cra b Cancer magister 

### Th e lif e histor y o f the dungenes s cra

b i s discusse di

n Section 4.1 5 o

f thi s 316(b ) Demonstratio n Report . Re d Roc k

Cra b Cancer

productus 

### Th e lif e histor y o f th e re drock

cra b i s discusse di

n Section 4.1 6 o

f thi s 316(b ) Demonstratio n Report . Slende r Roc k

Cra b Cancer

gracilis 

### Th e lif e histor y o f th e slende

r rock cra b i s discusse di

n Section 4.1 7 o

f thi s 316(b ) Demonstratio n Report . Europea n Gree n Cra b Carcinus maenas 

### Th e lif e histor y o f the Europea

n gree n cra b i s discusse di

n Section 4.1 8 o

f thi s 316(b ) Demonstratio n Report . E9-053. 9 5-1 3 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.9 4 5. 0 Impingemen t Effects Orego n cance r cra b Cancer oregonensis 

### Th e Orego n cance r cra b range s fro

mSt . Georg e Island , Pribilo f Islands , Alaskato Palo s Verde , California , although they ar e uncommon sout

h o f Point Arena , Californi a(Jensen , 1995) . The y ar e foun d i n holes , crevices , empt

y barnacl e shells , unde

r rocks , an do n pilings . Althoug

h the y occu r i n th e intertida

l zone , they ar

e mor e plentiful subtidally t o depth s o f 43 5 m(142 7 ft

) (Gart h an dAbbott , 1980) . Oregon cance

r crab s ar e usually reddish-brow n or orang e abov e an

dlighte r below , wit

h dark

colore dclaws . Th e carapac e colo r ca n vary , however , an

di n som e area s white , mottled , o r stripe d crab s ar

e common (Jensen , 1995) . I t i s astout , smal

l cra b wit h acarapac e widt

h o f 31. 9 m m(1. 3 in. ) i

n male s an

d47. 1 m m(1. 9 in. ) i

n female s (Gart

h an dAbbott , 1980) . (Jense

n [1995 ] report s asiz e t

o 5 3 m m[2. 1 in.]) . The Oregon cra b ha s te n teeth ; the carapac e i s wides t a t the sevent h an deight h tooth . I n Washington population s (Puge t Sound) moltin g an

dmatin g o f th e Oregon cancer

cra b occur s fro mApri l t o June . On

e broo dayea

r i s typica l an dovigerou s female s ar

e mos t ofte n see n fro m Novembe r throug h February . Th e ovigerou s female s tha t ar e occasionally foun

dfro mApril t o Jun e ar e mos t likely carryin g asecon dbrood . Th e averag e numbe r of egg s per female i s approximately 20,540 , wit

h arang e betwee

n 10,000 and33,00 0 (Gart

h an dAbbott , 1980) . Orego n cance r crab s liv e among bed s o

f barnacle s andmussels . Although they fee dmainl y o n thes e crustacean s andmolluscs , polychaet e worms , smalle

r crustaceans , andalgae ar

e als o consumed . The

y ar e primarily carnivore s an

dtendt o b e mor e activ e a t night . Th e most abundantly impinge dshrim p specie s wer

e thre e specie s o

f ba y shrimp : Crangon nigricauda (1 7 percen

t ofth e tota

l macroinvertebrate s impinged) , Crangon nigromaculata ( 7 percent) , an

dLissocrangon stylirostris ( 7 percent) . All thre e specie s wer e collecte dthroughou

t the yea r wit h pea k abundanc e durin g th e winte r tha t wa s associate dwit

h storms . They wer

e impingedprimarily a

t night . Othe

r specie s o f shrim p suc h a s Pandalus danae, Upogebia pugettensis, an

dPeneus californiensis wer e impinge di

n relatively low numbers . Seve n specie s o

f cance r crab s wer e impinge di

n the following orde

r o f abundance : 1 ) Cancer antennarius, C. anthonyi, C. productus, C. gracilis, C. magister, C. jordani, and C. oregonesis. Al l o f thes e cra b specie s wer

e impinge di

n substantially highe

r number s a

t Unit s 1 through 5 . Thre e specie s {Cancer

antennarius, C. anthonyi, C. productus) wer e collecte di

n th e greates t number s an

daccounte dfo

r 3 7 percen t o f th e catch a

t Unit s 1 through 5 but

only 9 percen

t wer e collecte da t Unit s 6 an

d7 . Cancer

antennarius was th e mos t abundan t (2 1 percent) o

f all macroinvertebrate s impinged . Th e frequency of collectio n o

f smal l Cancer antennarius suggeste dtha

t Mos s Landin g Harbor/Elkho mSloug h provide anurser

y habita t fo r juvenil e crabs . C . anthonyi constitute dapproximately 4 percen t o f al l macroinvertebrate s impinged . The E9-053. 9 5-1 4 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.9 5 5. 0 Impingemen t Effects peak abundanc e in Apri l wa s compose d ofjuvenil e crabs . C . productus constitute d les s tha n 2 percen t o f th e tota l numbe r

o f macroinvertebrate s impinged . Again , th e pea k (June ) i n abundanc e wa s represente db y th e presenc e of smal l crabs . Dungenes s cra b wer e collecte d i n lo w number s (2 4 crab s fro mUnit s 1 throug h 5 an d 2 7 crab s fro mUnit s 6 an d 7 ) throughou t th e year . Squi dconstitute dles s tha n 5 percen t

of th e total numbe r

o f macroinvertebrate s impinge d at th e Unit s 1 throug h 5 intak e an d3 percen t a t Unit s 6 an d 7 . The y wer e collecte d i n ever y month an d di dno t displa y aseasona l pattern . Th e peak numbe r o f crab s an d squi d wer e impinge d i n Jun e (6 8 individuals ) a

t Unit s 1 throug h 5 an d i n Octobe r a t Unit s 6 an d 7 (7 0 individuals) . Ba y shrimp s Crangon

spp. Crangon nigricauda, black-taile dshrimp , Crangon nigromaculata, black-spotte d shrim p an d Lissocrangon stylirostris, smooth shrimp , commonl y know n a s "ba y shrimp " belon g t o th e Famil y Crangonidae . Shrim p familie s are easil y differentiate d fro meac h othe r b y thei r claw characteristics ; crangonid s ar e th e onl y shrimp famil y t o hav e subchelat e claws . Thes e shrim p ten d t o bur y in th e san do r mu dan dar e mor e flattene d than othe r shrimp . In Californi atoday , ba y shrim p ar e fishe d commerciall y primaril y i n San Francisc o Ba y (Figur e 5-4 ) an dar e sol dmainl y a s bait . However , in th e 1940' s an d 1950's , annua l ba y shrim p catche s fo r huma n consumptio n average d704,00 0 pound s wit h peak s a s hig h a s nearl y 3,000,00 0 pound s (Chac e an dAbbott , 1980) . Crangonfranciscorum, Francisca n ba y shrimp , wer e th e vas t majority o f

ba y shrim p caugh t

commerciall y unti l th e earl y 1980's . Th e black-taile d ba y shrim p i s currentl y th e mos t

commonl y caugh t

species , an d th e spotte d ba y shrim p ha s als o increase d i n abundanc e sinc e th e 1980' s (SEW , 1999) . Smoot h bay shrim p ar e rarel y take n i n larg e number s (Chac e an dAbbott , 1980) . Black-taile d shrim p Crangon nigricauda Th e black-taile dbay shrim p ar e foun d fro mPrinc e Willia mSound , Alask at o Isl aSan Geronimo , Baj aCalifornia , Mexico . The y ar e commonl y foun d i n estuaries , embayments , an d i n th e nearshor e ocea n environment , rangin g fromth e intertida l zon e dow n t o 5 7 m(18 7 ft) (Jensen , 1995) . Black-taile dshrim p liv e o n sand y an d mudd y bottom s an d ar e als o foun d around eelgras s beds .

E9-053. 9 5-1 5 MLP P 316(b ) Resource Assessmen t 4-28-200 0r r "' P.9 6 -*) 5. 0 Impingemen t Effects

E XZ a o •o c o a. Sa n Francisco , Montere y an d Mos s Landin g Contributio n t o Californi a Ba y Shrim p Landing s

198 6 t o 199 8

| Tota l |Sa n Francisc o I Montere y I Mos s Landin g

C M c o -*

rm c o i* - o o Ol Oi O O ) O * O ) o Ol Or

Or

Or

Oy O) Or Source: CDFGLandings Summaries 1986-1998. Figur e 5-4 . Reporte d commercia l ba y shrim p landing s in Sa n Francisco , Monterey , an d Mos s Landin g area s fro m198 6 t o 1998 .

E9-053. 9 5-1 6 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.9 7 

# I 1

1 i f 

# 1 I 1 1 I 5. 0 Impingemen t Effect s



# I Crangonid s can onl y b e identifie dt o specie s onc e the y reac h alengt h greate r than 1 0 m m(0. 4 in.) . Black-taile dshrim p usuall y becom e matur e after on e year , whe n female s ar e approximatel y 33mm(1. 3 in. ) an dmale s ar e approximatel y 2 8 m m(1. 1 in.) (CDFG , 1999) . Male s generall y reac h atota l lengt

h o f 4 0 mm(1. 6 in. ) an d female s 6 0 mm(2. 4 in.) , althoug h greate r length s hav e bee n reporte di n Sa

n Francisc o Ba y an d som e offshor e population s (FWIE , 1999) . Female s may liv e tw o years , whil e mos t male s di e after

on e year (CDFG , 1999) . Th e spawnin g seaso n of

blac k shrim p appear s t o occu r

year-roun d alon g th e Californi acoast , wit h peak s i n winter-sprin g an dsummer-fal l (FWIE , 1999) . Th e females , carryin g egg s unde r thei r abdomen , remai n partl y burie di n th e san d o r mu d durin g th e day . Th e egg s hatc h at night , a t whic h tim e th e female s emerg e an d beat thei r pleopods , creatin g current s t o releas e th e newl y hatche dlarvae . B y dawn , mos t o f th e larva e hav e bee n free d fromth e female . Fecundit y i s directl y relate dt o th e female' s size , wit h a n average-size d femal e producin g approximatel y 3,70 0 egg s (Krygie r

an dHorton , 1975) . Early-stag e larvae , foun d in th e surfac e waters , generall y occu r

in near shor e location s whil e late-stag e larvae , foun d nea r th e botto mo f

th e wate r column , ar e mor e likel y t o b e foun d in onshor e an d upstrea mlocation s (FWIE , 1999) . Th e planktoni c stag e last s fro mtw o t o fiv e month s (Krygie r an d Horton , 1975) . Blac k shrimp ten dt o migrat e fro mconcentration s o f lowe r t o highe r salinit y a s the y mature . A s eg g stag e developmen t

i n ovigerou s female s advance s fro mstag e on e t o stag e four , th e shrimp' s occurrenc e in mor e salin e water s als o increase s (salinit y average o f 24. 6 ppt fo r female s wit

h stag e four eggs ) (FWIE , 1999) . Highe r temperature s lea d t o large r size s o f ba y shrimp , presumabl y du e t o faste r

growth an d longe r

growin g season s Annua l abundanc e o f th e black

taile dshrimp increase ddurin g th e drough t year s (198 7 t o 1992 ) an d ha s remaine d hig h despit e increase dfreshwate r

flow s an ddecrease d salinities . Black-spotte dshrim p Crangon nigromaculata Th e black-spotte dshrim p i s foun dfro mth e Farallo n Island s i n northe mCaliforni at o Turtl e Bay , Baj aCalifornia , Mexic o (CDFG , 1999) . I t inhabit s shallo w coasta l water s an d i s typicall y foun d o n san dbottom s fro m5 t o 17 4 m(1 6 t o 56 5 ft ) (Jensen , 1995) . I

t i s mor e commonl y foun d i n nearshor e ocean environment s than in estuaries . Th e black-spotte d shrim p i s migrator y an d capabl e o f

swimming , howeve r

i t tend s t o b e mor e epibenthic , remainin g i n area s o f san dan d mud . Th e black-spotte dshrim p i s easil y recognize d b y th e eyespot s o n eithe r sid e o f thei r abdomen . Thes e shrimp ca

n reac h approximatel y 7 0 mm(2. 7 in.) i n siz e (Jensen , 1995) . Th e spawnin g seaso n o f ba y shrim p i s long , wit

h report s o f

ovigerou s female s bein g foun d durin g 9 t o 1 2 month s ofth e year

(FWIE , 1999) . Period s o f peak abundanc e o f

black-spotte d juvenile s i n th e Bay-Delt aare ahav e bee n highl y variable , rangin g fro mlat e sprin g t o winter . I t ha s bee n E9-053. 9 5-1 7 MLP P 316(b ) Resource Assessmen t 4-28-200 05. 0 Impingemen t Effects

hypothesize dtha t

th e Bay serve s a s acontinuatio n o f th e nearshor e nurser y are afo r th e black

spotte dshrim p (CDFG , 1999) . Sinc e th e mid-1980's , th e abundanc e o f black-spotte d shrim p ha s steadil y increased . I t wa s th e secon dmos t

abundan t specie s o f

shrim p caugh t

i n Sa n Francisc o Ba y fro m199 1 throug h 199 3 (CDFG , 1999) . Smoot h shrim p Lissocrangon stylirostris Th e smoot

h shrim p range s fro mChriko f Island , Alask at o Sa

n Lui s Obisp o Bay , nea r

Avil a Beach , California . It

occur s mos t

commonl y in th e subtida l are at o abou t 8 0 m(26 2 ft

) (Jensen , 1995) . Smooth shrim p inhabi t th e surf zon e on wav e swep t

beache s (Jensen , 1995 ) an d ar e sublittora l in region s o f

har dsan do r

mixe d roc k

bottom s (Chac e an d Abbott , 1980) . Smooth shrim p reac h approximatel y 61mm(2. 4 in.) in lengt h (Jensen , 1995) . The y ar e th e leas t abundan t specie s o f

bay shrim p caugh t

b y fisherme n i

n Sa n Francisc o Bay . Smooth shrimp hav e bee n caugh t

i n wate r temperature s rangin g fro m8.7 ° t o 16 ° C (47.7 ° t o 60.8 ° F ) an d a t salinitie s rangin g fro m5 2 t o 10 0 percen t seawate r (Chac e an d Abbott , 1980) . Smooth shrim p ar e faste r movin g than othe r

ba y shrimp , probabl y du e t o thei r mor e challengin g environment . The y fee d o n othe r smal l cmstacean s an dclam s (Jensen , 1995) . Marke t squi d Loligo

opalescens Th e marke t

squi di s amembe r

o f th e clas s Cephalopoda ; squid s an d octopuses . Cephalopod s ar e highl y organize dan dth e mos t intelligen t

o f th e invertebrate s (Hochber g an d Fields , 1980) . Th e gian t nerv e fiber s o f

th e marke t

squi d ar e use d in neurophysiologica l research , addin g muc h t o ou r understandin g o f

nerv e impulses . Marke t squi d rang e fro msouther n Alask at o Isl a Guadalupe , Mexico , bu t

ar e mor e commo n fro mBritis h Columbi asouthwar d (Hochber g an d Fields , 1980) . Marke t

squi dar e pelagic , livin g i n coasta l water s bu t returnin g t o shallo w inshor e water s t o spawn . It

i s th e onl y specie s o f

squi d tha t

i s abundan t

inshor e (Hochber g an d Fields , 1980) . Marke t squi dar e translucen t

blu e i n color , bu t

vary fro mamottle d gol d an d brow n t o adar k brow n o r red . The y hav e a

n ability t o chang e color ; thi s "socia l signaling " i s use d fo r courtship , schooling , feeding , an dfo r camouflag e whe n frightened . Squi d hav e elongate d bodie s an d swi m b y je t propulsion . Mal e marke t squi dreac h 27 5 mm(1 1 in. ) in siz e (no t includin g tentacles ) an d female s approximatel y 20 0 m m( 8 in. ) (UCLA , 1999) . Femal e an d mal e marke t squi d ma y reac h maturit y a

t dorsa l mantl e length s (DML ) a s smal l a s 7 2 t o 8 1 mm(2. 8 t o 3. 2 in. ) (FWIE , 1999) . A t 1 5 m m(0. 6 in. ) DM L squi dar e reporte d t o b e approximatel y 5 0 day s old .

E9-053. 9 5-1 8 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.9 9

5. 0 Impingemen t Effects Marke t squi dspaw n year-roun dfro mSa n Francisc o t o Baja , but

exhibi t biannua l spawnin g peak s (Starr

e t al , 1998) . Th e majority o f spawnin g activit y i n souther n Californiasqui d population s occur s fro mDecembe r throug h March , but

ma y als o occu r

i n July . Squi d population s i n Montere y Ba y spaw n mainl y in Ma y an d June , an d t o alesse r exten t i n Novembe r (Hochber g an dFields , 1980) . Adult s migrat e fro marea s ove r th e continenta l shel f

t o nearshor e sand y an drock y botto mbays , ofte n nea r submarin e canyons , t o spawn . Both mal e an d femal e squi dar e termina l spawner s an ddi e after spawning . Starr

et al . (1998 ) stat e marke t

squi d hav e a lif e span o f on e t o tw o years , whil e Hochber g an d Field s (1980 ) repor t mos t spawner s appea r

t o b e thre e year s old . Th e femal e produce s from18 0 t o 30 0 egg s encase d i n acylindrica l capsul e an d ma y extrud e 2 0 t o 3 0 capsule s durin g aspawnin g even t (Starr e t al , 1998 ; FWIE , 1999) . Th e firs t eg g case s t o b e lai dar e attache dwit

h thi n stalk s t o th e botto msubstrate . Subsequen t layer s (approximatel y 2 0 t o 3 0 capsules ) ar e the n deposite dunti l larg e cluster s ar e forme d (Star r e t al , 1998) . Eg g case s hav e bee n observe di n depth s rangin g fro m3 t o 18 0 m(1 0 t o 59 0 ft) (FWIE , 1999) . Th e egg s hatc h in 1 5 t o 9 0 days , dependin g on wate r temperature . Squi d d o no t

hav e atru e larval stage ; youn g squi d ar e calle d hatchlings . Th e hatchlin g squi d loo k lik e miniatur e adult s an dhav e amantl e lengt h of 2. 7 m m(0. 1 in.) (Starr

e t al , 1998) . Hatchling s liv e of

f thei r yol k sac fo r severa l days . The y ar e wea k swimmer s unti l the y ar e aroun d1 5 mm(0.5 9 in.) DML , an dtherefore , can b e widel y disperse d b y current s (FWIE , 1999) . A t 7 0 t o 8 0 day s ol dhatchling s hav e becom e stronge r swimmer s an d begi n t o for mschool s (FWIE , 1999) . Juvenile s gro w rapidl y an d schoo l fo r approximatel y 4 t o 8 week s i n semi

protecte dnearshor e area s befor e beginnin g t o dispers e int o dee p wate r (Starr e t al. , 1998) . Squi dar e carnivore s an dfee dusin g thei r tentacles , preyin g o n smal l cmstacean s (euphausiids , mysids , etc. ) fishes , polychaet e worms , an d thei r ow n young . Hatchlin g squi d fee d o n smal l planktoni c cmstacean s includin g cra b larvae , copepods , an d penaei d shrim p myse s (FWIE , 1999) . Squi dar e consume db y man y specie s o f fishes , birds , an d marin e mammals . Marke t squi dar e fishe dcommercially , markete d fo r huma n consumptio n o r

sol d a s bait . Figur e 5- 5 show s th e reporte dMontere y are acontributio n t o th e commercia l landing s fo r marke t squi d i n Californi afro m198 6 throug h 1998 . Historically , th e squi d fishery ha s bee n importan t t o th e centra l Californi acoast .

E9-053. 9 5-1 9 MLP P 316(b ) Resource Assessmen t 4-28-200 0