The Resources Agency DEPARTMENT OF FISH AND GAME FISH AND BIVALVES AT BOLSA CHICA MARSH RE-ESTABLISHMENT PROJECT. Eric H. Knaggs and Rolf E.

Transcription

1 . 7-1 ' ~ - -* t.,:. - w State of California. The Resources Agency DEPARTMENT OF FISH AND GAME FISH AND BIVALVES AT BOLSA CHICA MARSH RE-ESTABLISHMENT PROJECT Eric H. Knaggs and Rolf E. Mall MARINE RESOURCES Administrative Report No January 1981

2 FISH AX9 ElVAL,VES AT BOLSA CHICA Eric H. linag6s?/ and Rolf E. I!all- 3 / The objectives of thz study arc: I. De.ter111-in.e changes in the ncial>+-r of specj-cs of fishes and bi.vzl-\.cs before I11:.ase I ai~d durj.cg Phase I at Holsa Chicn Marsh. 2. Determine. if CaliforLlia Depal:tncnt of Fish ai~d Garne's predicted bcnefits in l'i:cst.. I werc ac11ievc:ci by i.ncreases in fish species, 3. Dc tel:i:iine i.nf:lucnces of wzter ri;.enngemcilt prac tr.i.c.e:i upcjri f is11 an4 bi.val.vc ~~~>po:;itioi~, This report is divided into two inajcr topics: (I.) tile iishes ei~d tiv:llves collected in July, August, and Scpte-bcr arid (2) e discussion of the project: clbjectives ziter four qunrtc?:.o of sc?.n;3lir!g. Fi9.cen speeicc of fishcn and elght cpcc.ics of bivalvcs were collcct.ecl fro:n ~III.IC~ Eol.sa I3ay and south Iiolsa slough ill July, hu~ust, a11d September j.360. Giailt k.clpf l.sh, Betlr;.,.:ostic7ius?~ost~-atu:;.; gray snoot:hhound, ii:listsz~!s cnl ifornicz~s; California halibu:, 2:'ai~clichthys califoi~r:ic~.~s; yell nvf in croaker, li1mhi?iiza roncadoil; 1:Teshington clam, SU,T~L?GV~X:~?~i/kt~LLi; egg c~c!<l_e, Lnevica~diu~l; subst~>iai,u:n; aild a small burl:o~;.ing clnri~, CoopcreZZa su!)di~phr,77a, llave not been previously ir~pc!rted from inner Bolsa Cay. 'J'he number of fish species i.n outer Eclsa Bay cl~r.ny,?d from 10 ~rior to Fhcrse I to 18 during Ph~sc 1. The nui:,ber- of / 1 -. Marine Resources Region, Admlnistratiuc Report No. 61-4, January / Califolni-a Ilcpartinent of fir;?^ and Gzn.2, Planning I~L-zilch o:l I.P./I. to :.:at-ional Marine l?ichclrie.s Service, Southv;:.st Kegion, 300 Sc. Ferry Street, Terminal Island, C / Mavj'.uc I:.c:.;~urccs 1:~:g:l on, Gal-if orni.3.(;txt e Fisheries L.r:.bo~:r:tory, 350 C;nScicn l;llorc, Long I3cac11, CA 9C3S02

3 fish species in inner l;ol.sa Gay and south Eol.sa slougli changed froin three pri.or to Phnse I to 24 duri.ng Phase I. Eleven species of bivalves were found in outcr Bolsa Gay both prior to Phase I and during l'hase I. The ilurnber of bivalve specri.es i.n inner Bolss: Bay changed from tvo prior to Phase 1 t.o nine during Phasc I. Kith the water r?r<nn,qement practices of Fhase I in icner Eol.sa Bay and south Illol.sa slougil; t.lie nu1nljc.r c!f resident fish species is 14, wliilc t.he numbe~: of resident Liva1.v~~ is five. A11 three study objectives ill-c disccsst~cl n!?d recorriilcndations are 111ade on water n:snsgmer,t practfces concern in^ fishes and bivalves in inner- Holsa Gay srid south Bolsz slough.

4 l'iiis study 3s designed to cx~inlne thc fir;hc;ks and bivalve? that in11abj.t I',olsa C'nica c!:s;'in~ I'hzisc 1 of thc ninr;h re--estnl1l.i~111fii7ilt: project. I'hcse I is the t-ime p2riod frcn tile orig.i.riz1 opening of t.!le tri.dc gat:es in mid-0ci-oht-: catil.. therc arcs. activi-tic:; c?ltcri.nir, this l'hzse 1 salt rfiarsi-~, F.?:ea J)L~.?.r.crL:,tioc Our gel;zzi:l s?-mi>].e r.:rc;;s of j;o]i:;; C:;jc;: );ar;:h arc ::s fc)110~-::: 1. OilLc~ iiolsc.; i:,sy :is t.hc: jl?~c;-t:idal. ~~c-~r!:lon of 133:!.::a Chic2 '.'-%--' I'Lci L : -1 \t:lthj-, Stat<; 1,2ii..c',,5 li~~:li.l.cd by the!,';,riier Avi:rLui2 hi-i.!?r:e (TJos Pntoa 1)ridgcj fix the nv~:tl~r,:c?st and t?:c t-i.de g~:r:rs on the rout1-1- eclst (Figl~rc. i). 2. Inner Lais2 1;::pi is the i.nt~rtiilsl.!?ortion of l;nl.sn Chica 1.1arsil boundl::d by t-!:r. le-vee system on the r;o!-'ihczst, t:i.dt. gatcu or1 the niirth;::est v2.t;j.t~:' ~~~al.l;i;ay on the ~:~i!tli~a',~i, anii Pacific Ctj.i~t I!:! ~:ib';:y On tl, r.: SOI.T~:~~~~C S l: (17ign1-p. 1). 3. Soeikh Col.sn Sl.c.1:gli is tlxc intctrtidzl pclrt.i.c:? of ZoS.c;a C:!ii.r,?- Plnr~?: hi::unil{sd ljy tl.:t. vir-;it.o~: r:al.l;,,:iiy oil. Liie no:.tlis:est,!.cvcc

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6 system c;-c the nortilec-.st arid soulhenst, arid PaciEic Coast 1li~k~:~~ay on tlic sout'iwerit (FLgu~i: 1), Saxplc Siti: Locat:l: 3;::; Site nu~scr 1 is iri SUU~:~ P.;rl~i? ~:lc)~~gli i7.l tll~ r,ul:t!lt?a~t COT~?CT elf t.k~c marsh (?'~.cl:i-~ 1.). This site v:,:o chose11 1)::cnuse it: \,i:;.; a land 2.r cln nn?. suhjc\-.t pcrj.oc!ic floodi.1:~ before l'11c.i;:-: I, but ciurl.iig Pi-:a.c;c L 5.: is a. l.?r,tcr a?-.?,? infl~!ciiccd by ti i'cs. T:lcr:c:ore, all f:i.r!ies cr~ptuxcd ;!c: t?ii::, si!:c krc.-yi: in,-\rn.ded ':.i~i:j s ltc :;:fire tlir. t:li.e gates we:-.: c!;-;pned. Site n:!:-i:lcr Z is I.ncnted in nor.t!i IZoI-sa.t,lrju;:'n directly across iiur ri.idd]c i:-;1cr:d. T1jj.s ::s'.tc iu:cs ch::::.?:! ~c-c~u:<~ it 1.: \:~t~r. ileayc::t: i : 1 b. : Ti.;f:.; ~,?-i:r *b,jzr a I.c.:!~ aritc: :lo!. CI?,',.~C:CS- L3 t:idc,l f :!.oc~dl;l;: beiore I'i?;?e I. Sj.1;~ ~;".:...:?;~~:s 3 ;nd!. ; nl-2 in j.~:;;::.r l;02.:;;: T:15s l;?~:; 2 l,??.t:p:: 21;~;:. Ijc;o;.\: P;:r;,:;*. 1 n~lci, crl:!.ijl~.:-.s to 1: 8 i-!at:@;. c.j:e;?.. 'l:':;t..li::f(jre, fis.,!~ ~11r; - - t)i-v:j.l.~~s, g)j.,:<::-~~~i;~; at. i)!<..~.:! s<-::c.:z: <lj~r:,;-i~, ;':!.,<IC-C.. P. 7 p.2-- 1:r: - r,,,..i.bl, L-I.:~~I c ~ ~ ~ ~ i.p. ~ :i.~;~i<:: ~ : z<oi.~a ( : ~ ~,. ~ y ~ ~,.,A 1. could 1 ) ~ co.:;::rirt,.: 1.0 $<...L. tc --T.-7-:>i.r I~.,L. 5 j.5: 41"~ otter Eo!SP" j?;?.y (!';f;i.!j:~ I). li;l?.i.:; ~ 2. l.?;s t ~ zelect~d :Fs;r cor;p<i~:i.i:g; lrl:asc I iis'!? colleccioil:-: j.~-~ cat:'1: l3iil~:a E~:J :,~$i-.!; 77: pre--~l!ase I fish co3.1.ectio:1s fro:,? 1:hj.s arc::!. S5t.c ~:.~l::iiirr. 6 is iil ovter Bnlsa I:!y. Tii::.s s:iec., tias c.e,'.ec:.cd f.or cctr:!;~i;~ring Li.veivc:; ca:,turcd I)cforr: 2:-id dii.!-li;~, IJliase I.

7 We have divided this report into two major topics as follows: (1) the fishes and bivalves collected in July, August, and September 1980 and (7) a discusslo11 of t:l?e project ob-jccti.ves after four quart-ers of sampling. FISHES AIm BIVA1,VES COLI.,ECTED IN JULY, AUGUST, AED SEPTELIGER 1980 llatcrials aild Methods l.taterirtls and ~i~etf-:oc',s used to collect iiclies during the August collectioll!:ere the seme r-is dcscribcd Ly Ri~aggs oil; Mall (13eOa, b). No m-inno~ traps were used to collect fl.sf!es. S~ilrple sritc $7 (Figure 1) was not samplcd eincc t.l~c. proposal 1-0 a!!ci~ sen c-aler from 1-hc area.ill.- side the Phase I cili.kcs t:c flow outside and rerl.ooj?, small. pi~rt:i.on of the foi-inc?r oetla.l;ds was h~*c.t:i:~i, (Ki12ggs iind I.laS.1,!.?3i)c.). Durj.r!:.: our August Xe::ult-s F j.:;i? :-? Fivz b:--;c;-sc.in~ a?:;', :mi)<. :;ill.---;;:,t. sr.l-;plc s:jico \:?:re c11cj::ti:i for c~1j.c~-- tion of fishss on L7,1,,.;u:it 21, 1980, L'iftcen spcc5.c~ of fish weri:. collected from inner B,32.::a Gcy an.? sc:~!t.il?:olsr; slc~ii~h ~t r;it.os 1, 2, 3, and CI, (T,?L.l.e 1 ). Fcq~r, L oi t!i::si., ti~ic ~;icb!:t 'k-clpf is11, Ilc-la-7.0:itlz i?ostraizia; Gray srs~ooti-~11~unc!, ill~ist;aiun ~ azf.fi~*i~i~~q Celif ~ri?-i a hali-but, Pc~aZ.ich-Llr~s ~a7y.i.fol~nic~:s; aild yel1.owfi.11 c.rcaker, li:i?ii~)7iil~ ro~:cador have ilot bee11 re.portecl previous]-y frox inner Hols~ Bay 2nd sauth Bo1sr.i.slough. Tell species of fi.c.1lc.s were captzred in o11t.c~ i;ol.sa Uay r:t site 5. TWO of these species, gray s~!loo;l~hound and Cs1ilorr~i.a halil~ut. have not: heen re- po~-~ecl here previous1.y. Biv~lv~:, -- - Eight species of bivalves werc collected o!~ August 27, at: site

8 n-a n- on- "-3 L?O mc m w YIN uvv -u uv vv vu O.nN OIO a m C I N ~ O U,,WN 4 N m.i." ",a UOOOC r,qn r(cinnr\' (ON N n- n -a0 n- - N m.3- N O m -44 N"-, 4 uvv vu U O\D-f04N n n n n n- n-- A-o -nu- m o n x o n - ~ -AN --anm J ~ N \ C. urn -4 mom- mom m-woo I O Y - ) ~ mh.40~ my. m 0. 4 ~ mm-i 0-f-f-4 uuu vvvv vu vu.>vvv vvv Uuvuv.,hWY)? Nmm h*\d-fc m a rr r(444-l 04 - Y ~ N O I ~ C O YOrn4NW A/. n 0 A n n me- ---w-c. 4n-A Y)-A4 VI--~VI dm-n hmm 4-44 cj~cm-fdh dm-4 nwm4 N N A ~ N uvu uuuv vuuuvu uvvv vvvv uuuu.d 0-4. n. 4 OO4NN O"3m44NOm Om44Y)N Y)t7WP-YIhNP-O. o - ~ o o r n OVIN "lo m Y) m A A A A

9 4 (Table 2). Three of these species, Washington clam, Saxidomus nuttazzi; - egg cockle, Laevicardiwn substriatun; and small burrowing clam, CoopereZZa ubdiaphana have not been reported from inner Bolsa Bay. Six species of bivalves were collected on July 16, 1980, and September 10, 1980 at site 6 All species of bivalves collected at site 6 have been reported from outer Bolsa Bay prior to or during Phase 1. Discussion Fishes Large numbers of topsmelt were taken in all bag seine sets. An exotic fish, Tilapia mossambica, was observed and captured throughout Bolsa Chica Marsh. Another exotic species, the yellowfin goby, Acanthogobius fzavimanus, was also collected in significant numbers. The yellowfin gobies.captured ranged in size from 119 to 302 mrn total length. Zeptorynchus, occurred at all stations sampled. Bay pipefish, Syggnathus Male bay pipefish were brooding larvae. Bivalves A clam bed located at site 4 contained a number of different species of bivalves. Recruitment of the 1980 year class of common littleneck clams, Protothaca starnirzea, and Washington clams was successf ul. The common littleneck was sampled in larger numbers than the smooth chione, Chione fzuctrifraga, (Table 2). This is the first time another bivalve species was more numerous at site 4 than the smooth chione. A large population of the conlmon littleneck continues to occur at site 6. Correction to Fish Collected at --- Balsa Chica Marsh May 15, 1980 Certain gobies in the May 15, 1980 collection were mis-identified. The goby identified as CZeveZandia ios was in actuality two species,

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11 C. ios and c2i~i~cll~za 9-c~:!;iia (Table 3). All other fishes were correctly DLSCUSS10:; OF PROJECT OSJECTJVES AFTER FOUR QUARTEP,? OF S~L~~I'LIKG Determine Cl~rr!gcs %;-I -. tile Kunl.L>ee of Specfes of Fjshec; and -- Bival.vcs Hefo-1-c: Phase I and I1urlng 12iiasc. I at:!;ois:~(2':-i'l.c~ :iz.r-,ch Firlles. Ten specits of fishes wcrf collcctcd ii? cuter Bolts Bay prior to l'hasc I (T;b?e 4). Scven ~peci.es of fish?~ wore cci:::11lcv3 i.n tke faj.1 of 1979, and the tot;:? r,u;nl,r of species ir.r:-i~.>i:;;ccl to 1.0 vith t-he Felruai:y S98C sa1::pl.e. 'I'hr. r!illillcr of fish spccis!:s coll.~:ctc~d in Mas 19SO increased tile total. f.i.~li.sl~zci.cs frlund in this 2~-i'~ t.0 1.5, tjhile a tat;-l of 1.8 fist). ~;.-,r.ci.es t.:ei-r: (Tab1.c 4). f'c;~~:;! tfh~?~: C~UI: rjanpli~;;; r.;;ried in Au:;ust. 1.5iGC1 r. ~'hl-ce s:?c:s$..r:s of fi c;l:;~!< vr:xe coll.<ict~.d ii.1 <:lr~ci Bol ::2 J;::.y pr.i.0; to ~'~~~~~ 1 ('i::.!j].c> 5). E~.;;}J?: :,,;;,:-:~.:-es of fj-~;:lps \,:,.y:-,, - < ~, ~ J. ~ C 2.17,. ~ ~ t:ij,->, ~? fa1-j n.f 1.979, ancj 1.>1t? t or:al ll~~ii.t~r.:r ol si)<:ci c?s r.::ibt.i;rc.,.? cc.,r;tirrx-g Lo :fucl'e..,<-c to?3 durrij-:; Zinzrj;;..:i: I.'jhC, (5'i:l:l.c 5). KC) fis':i 5pc:c:.<?s [\:pl.q foylr~:l ;i:: c~;;?: s;i::,,se *;:i?..r>:; :i.11, :,;ul.jl f;~~~-i:>;7. pj(~,cl;;h ~"--jc,r to r'ilar,p I r;.irl.cc [-?>.-.c,-...,. ~2.SX:I~~C ~:i.t<:.:; tq?~?:~> ~<~il:~ ~.:I:F;;S;!!(!t ~~!bj~~t: i.1:.. c flc3:r,. 6j.cl-it' s:>cclcs of Li.si~c.s v?erc: col.lec~e.?. i1-i Mot.~.j~!:i.,cr 1.979, while 1-.:~YF..?. of 1.3 specics wc~:e fov:\cl y'lt-i: :: tovr c!ur:.rizc.r-s c.f suinp 1. in (Y'F:'~.I. 1.: 6 j. 1.k e>:p~c'c.-d the T,IIL~~.I~'I: 01 fish sr!ccj.ec; fourid in outer I!r;S.sn Bay dnrin& Pi-iasr: :r to be jp;r:~~xir;:z?-nly tile s::rrc oc, foa::c'! prfr~r to Phzse I sincc! thi.s area wzs n:ot r.:odj.ficd pl-)yslcall y. l'1.c oilly chan;;? t.iiat: occurred $11 tlli:: arc2 1.7;~s a gre;.t.c? vo!.uri~r: ol' t!:!.i:c~: flovi.ng t.:hrc)~,gh outer Lro1.s~ 31;:~ to flood and c-iro-in iriricr Bole:: T;r:y and south BoS st1 slol~y,h. 12e-vcr tl~:t_l.c-ss: 'ihere w;:.:; iisi 1)Lncr~i~.sc f TO:;! 1.0 f is!^. species found prior t:o

12 TABU 3. Amendment to Fishes Collected at Bolsa Chica Hareh May 15, Prephase I pond numbered areaa Site Kucber of sets corresponding to Total length in m TL KO. Bag seine Gill net Scientific name Common name our site numbers No. captured* min.* max. * hchoa conpressa deepbody anchovy Mne 1 Fmdull~~ parvipinnie Calif. killifish 2 Clerwlmd:'~ ios arrow goby 2 Xomti.,ogoSius f ~vinwnus yellowfin goby 1 Athdr:n~;;s affinzs topsmelt 99 Quietula y-ca~da shadow goby 32 Atherimps affittia Ftoldulw pal-~ipittnie CLat~clo~dia ins Lqchoa c~~z*es:a C:iic:u2a y-cauda Xtheriqops affinis FaduZu parvipinnis AccltlcpcSius flnwimm::!~ Zt:ic;:t..;j.~ rlrcs;<l-h CLcvc lundia ioc AtharLnc,-s afj^i?~is iiyps"?s~ttc guttulata Cles'clmddia ios Po~-;cl,:hy.? q;riaster Hjp;cy;etta guttulnta Qw~togmter aggregata Athcrinops af~~inis Clc~~~~l~~dio ios Lcnt~cottr~.? n-mntts L1r02~,~hm hhlleri i!u:$ i c.cilha2:~s At;!ezinop~ aj3,finis Ojr!:; t;.cas ccz. nggreaata Leptoc~ttu armatw, Tilopia nossarhica Ftmd:rlus prvi~irntis 0:llicitl:p rr;l,1;silis CIevaimdis ins Xcm thuqobi,~ f lavinnnus Syn,-nat;~w 2cptorhpchuo Qirietulc y-cauda Clevelandia ios topsmclt Calif. killifish arrow goby deepbody ancl~ovy shadow goby topsmelt Calif. killifish y,-ll,,.r:., -,,:-* 'Ic:l%: r.clzuctccr arrow $;0'3y to;13nclt diamond turbot arrow goby j acksmelt shiner surfperch yellowfin goby round stingray shadow goby spccklefln midshipman diallio~ld turbot shiner surfperch topsmelt arrow p,oby fit a-hnm sci11ni.n round stingray stripcd mullet topn~nclt shiner surfperch staehorn sculpin tilapla Calif. killifish longjaw mudsucker arrow ~oby yellowfin goby bay pipefish shadow goby none Number in parentheais is second set

13 TABLE 4. Species of Fishes Captured in Outer Bolsa Bay Prio- to Phase I and During Phase I. Species of Fishes Prior to phase I Arrow goby California corbina California killifish Deepbody anchovy Round stingray Shiner surfperch Staghorn sculpin Striped mullet Tidewater goby Top s melt Species of Fishes During Phase I Arrow goby Bay pipefish California halibut California killifish Cheekspot goby Deepbody anchovy Diamond turbot Grey smoothhound Long j aw mudsucker Shadow goby Shiner surfperch Staghorn sculpin Striped bass Striped mullet Tilapia Topsmelt LThite croaker Yellowfin goby

14 TABLE 5. Species of Fishes Captured in Inner ~olsa Bay Prioi to Phase I and During Phase I. Species of Fishes Prior to Phase I 1. Bay pipefish 2. California killifish 3. Topsmelt Species of Fishes During Phase I Arrow goby Bay pipef ish California halibut California killifish Deepbody anchovy Diamond turbot Giant kelpfish Goldfish Grey smoothhound Jacksmelt Longj aw mudsucker Northern anchovy Queenf ish Round stingray Shadow goby Shiner surfperch Specklefin midshipman Staghorn sculpin Striped mullet Tilapia Top snie It Yellowfin croaker Yellowfin goby

15 TABLE 6. Species of Fishes Captured in South Bolsa Bay Prior to Phase I and During Phase I. Species of Fishes Prior to Phase I Species of Fishes During Phase I No species of fish since this 1. area was a land area not 2. subject to periodic flooding Arrow goby Bay pipefish California killifish Deepbody anchovy Diarnond turbot Northern anchovy Pacific bonito Shadow goby St aghorn sculpin Striped mullet Tilapia Top smel t Yellowf in goby

16 Phase I to 18 species found during Phase I (Table 7). We did expect an increase in the number of fish species in inner Bolsa Bay, but we expected the nilnlber of fish species to level off or increase very slowly after several quarters of sampling. With this leveling off of the total number of fish species captured, we could assume that we had captured the fish species inhabiting inner Bolsa Bay. This leveling off of the total number of fish species captured did not occur, and the total number of new fish species captured continued to increase during our sampling (Table 7). Thus we can hypothesize that either (a) our equipment was not adequately sampling all species of fishes, or (b) fish species continued to be recruited to this area during our sampling. We have rejected the first hypothesis since the project sampling gear has been used successfully to capture large numbers of fish species in similar coastal areas of southern California. The number of fish species found in south Rolsa slough continued to climb during the sampling, but at a slower rate and with fewer species than inner Bolsa Bay (Table 7). Total number of fish species found during Phase I increased over the number of fish species found prior to Phase I in outer Rolsa Bay, inner Bolsa Bay,and south Bolsa slough. Thus, we feel the opening of tide gates to allow tidal action in inner Bolsa Bay and south Bolsa slough has been successful in increasing the number of fish species focnd in the Bolsa Chica Marsh. Eivalvcs. The number of bivalve species found in outer Bolsa Bay was 11 prior to Phase I. During Phase I, wc found only three species at the beginning of our study (Table 8); however, by the end of our study a total of 11 species were found in outer Bolsa Bay. We feel that most of the bivalves in outer Bolsa Bay have been discovered since (a) the number

17 TABLE 7. Number of Fish Species Collected by Area and Time in the Bolsa Chica Ecological Reserve. Number of Species by hredl Outer Bolsa Inner Rolsa South Bolsa Date of collection 3 Bay Slough Prior to Phase I Phase I Sept.-Nov Feb Apr.-May Aug / - The number of species is cumulative for Phase I

18 TABLE 8. Number of Eivalve Species Collected by Area and Time in the Bolsa Chica Ecologiczl Reserve. 1 / Number of Species by Area- Date of collection Outer Bolsa Inner Bolsa -- Bay - Bay Prior to Phase I Phase I November 1978 January 1979 March 1979 May 1979 July 1979 Noveinber December 1979 January 1980 March 1980 May 1980 July 1980 August 1980 September 1980 no sample no sample no sample no sample no sample no sample no sample 9 no sample 1 / - Nuinber of species is cumulative for Phase I

19 of species has equalized at 11, and (b) 11 species is the same number found prior to Phase I. Only two species of bivalves were found in inner Bolsa Bpy prior to Phase I. The number of bivalve species found during Phase I has increased to nine (Table 9). It 'appears that recruitment in inner Bolsa Bay is still continuing (Table 8). Sampling for bivalves was not conducted in South Bolsa slough. Opening the tide gates does not appear to have affected the number of bivalve species found in outer Bolsa Bay. h'everthe1.c~~ this action did increase significantly the number of bivalve species found in inner Bolsa Bay during Phase I (Table 8). Determine if California Department of Fish and Game's Predicted Benefits in ~hc?se I were-~chieved b\r Increases in Fish S~ecies It is stated oi page 26 in a Department of Fish and Game report en- titled "Bolsa Chica Marsh Re-establishment Project, Volume I," "that a predicted benefit would be an increase in the number of species of fish from four collected during pre-phase I to nine species during Phase I." It should be noted that we assume this statement refers only to inner Bolsa Bay and south Bolsa slough. Since the mosquito fish, Gambusia affinis, was found outside the Phase I marsh, there were only three species of fishes within inner Bolsa Bay and south Bolsa slough prior to Phase I. The number of nine species predicted in Phase I was exceeded by 15 species to a total of 24 species in inner Bolsa Bay and south Eolra slough (Table lo),. Thus, the predicted benefits of increases in fish species was exceeded by 2.7 times. Detcrrnine Influences of Water Management Practices -- Upon Fish and Bivalve Composition Since we believe the major impacts of water management practices

20 TABLE 9. Species of Bivalves Captured in Inner Bolsa Bay Prior to Phase I and During Phase I. Species of Eivalves Prior to Phase I 1. Bay mussel 2. Smooth chione Species of Bivalves During Phase I 1. Banded chione 2. Ray mussel 3. Eentnose clam 4. California jackknife clam 5. Common lit tleneck clam 6. Cooperella clam 7. Egg cockl-e 8. Smooth chione 9. Washington clam

21 TABLE 10. Species of Fishes C~,tured in Inner Bolsa Bay and South Bolsa Slough Prior to Phast I and During Phase I. Species of Fishes Prior to Phase I Species of Fishes During Phase I 1. Bay pipefish 1. Arrow goby 2. California kill if ish 2. Bay pipefish 3. Topsmelt 3. California halibut 4. California killifish 5. Deepbody anchovy 6. Diamond turbot 7. Giant kelpfish 8. Goldfish 9. Grey smoothhound 10. Jacksmelt 11. Long j aw mudsucker 12. Northern anchovy 13. Pacific bonito 14. Queenf ish 15. Round stingray 16. Shadow goby 17. Shiner surfperch 18. Specklefin midshipman 19. Staghorn sculpin 20. Striped mullet 21. Tilapia 22. Topsmelt 23. Yellovfin croaker 24. Tellowf in goby

22 have been on inner Bolsa Bay and south Bolsa slough, we will confine our - remarks to inner Bolsa Bay and south Bolsa slough areas. The passage of water between inner and outer Bolsa Bay is possible through three 48 in. (122 cm) culverts with flat tide gates on the outer Bolsa Bay side of each culvert. Many different combinations of opening and closing the three culverts have been tried during Phase I. However, only two coabinations have been used for lengthy periods of time: (1) one culvert open for the period mid-october 1978 to March 1980, and (2) two culverts Qpfn from March 1980 to the end of our sampling in August We were not able to determine statistically if one culvert or two culverts open was more beneficial to increased fish and bivalve species' immigration. We continued to find increases in the number of fish species in inner Eolsa Eay with either one or two culverts open. However, with only four data points, it would appear that more species entered with tvo culverts open (Table 7). The number of fish species (eight) remained the same in south Bolsa slough with one culvert open, but increased to 12 with two culverts open. The difference in nunbers of bivalves with two culverts open was that recruimtnt increas~d within a species such as the common littleneck clan, and Washington clam, and juveniles of these species were able to survive in inner Eolsa Bay. This may be related to water quality improving con- siderably when two culverts were open (Feldmeth and Associates, 1980). Lre defined resident fishes as fishes that were captured in two out of four of our sarcpling quarters able 11). Therefore, there are 12 fish species determined to be resident fishes in inner Bolsa Bay and seven fish species in south Eolsa slough (Table 12). The number of resident fish species in the combined inner Bolsa Bay and south Eolsa alougll is 14 species.

23 TABLE 11. Fishes Captured at Bclsa Chica Marsh During Phase I of the Reestablishment Project. Fishes Collected in Outer Bolsa Bay = 0, Fishes Collected in Inner Bolsa Bay = I, and Fishes Collected in South Bolsa Slough = S. Fish Name Months and Year Fish Collected 9-11/79 2/80 4,5180 8/80 Arrow goby Bay pipefish California halibut California killifish Cheekspot goby Deepbody anchovy Diamond turbot Giant kelpf ish Goldfish Grey smoothhound Jacksmelt Long j aw mudsucker Northern anchovy Pacific bonito Queen fish Round st ingray Shadow goby Shiner surfperch Specklefin nidshipman Staghorn sculpin Striped bass Striped mullet Tilapia Topsmelt White croaker Yellovf in croaker Yellowfin goby S I-S 0 S-I I-S I 0-I-S 0 S

24 TABLE 12. Fish Species Considered to be Resident in Inner Bolsa Bay and South Bolsa Slough During Phase I of the Eolsa Chica Marsh Re-establishment Project. Inner Bolsa Bay Bay pipefish California killifish Dianionf! turbot Long j aw mud sucker Round stingray Shadow goby Shiner surfperch Staghorn sculpin Striped mullet Tilapia Topsinel t Ycllowfin goby South Bolsa Slough Arrow goby - Bay soby California killifish Deepbody anchovy Shadow goby Top sme 1 t Yellowf in goby

25 Fishes that use inner Bolsa Bay and south Bolsa slough as spawning and nursery grounds are topsmelt, shadow goby, arrow goby, bay pipefish, and tilapia. Fishes that use these areas as nursery grounds are California killifish, longjaw mudsuclter, diamond turbot, staghorn sculpin, striped mullet, California halibut, and yellowfin goby. Fishes that use inner Bolsa Bay and south Bolsa slough as nursery areas only, may spawn here also, but we have no spawning data on these fishes. We defined resident bivalves as those species that were captured in two out of the four delineated time periods (Table 13). We did not sample south Bolsa slough for bivalves. The resident bivalve species in inner Bolsa Bay are bay mussel, banded chione, bentnose c1an-1, common littleneck clam, and smooth chione. To predict if any other fishes or bivalves might occur in inner Bolsa Bay or south Bolsa slough, we reviewed our field data for outer Bolsa Bay and animals captured in Ihntington Harbour (Hardy, 1970). Eased on these data, we predict that the sl.ough anchovy, white croalter, chcekspot goby, California mactra, gaper clam, Washington clan, California jackknife clam, rosy razor clam, nestling clam, and mud piddock, will probably become resident anirnls. The black croaker, shovelnose guitarfish, striped bass, and California corbina, may invade inner Bolsa Bay and south Bolsa slough, but they are found in such low numbers in surrounding waters that these anirnals will probably not become estrablished as resident fishes. A population estimate of fishes in Bolsa Chica Marsh could not be made with our study methocls. However, a qualitative estimate of the abundance of fish species was made for the Marsh. For fishes captured with a bag sejne, the most abundant fish was topsmelt in outer Bolsa Eay, inner Bolsa Bay, and south Bolsa slough (Table 14). The second most

26 TABLE 13. Bivalves Captured at Bolsa Chica Plarsh During Phase I of the Re-establishment Project. Eivalves Collected in Outel- Bolsa Eay = 0, and Bivalves in Inner Bolsa Bay = I. Banded chione Bay r:iussel Ben tnose clam California jaclckriif e clarr.: Cornor! 1 it t leneck clan1 Cooperella clan1 Egg cockle Gaper clam Native oyster Nest 1 i ng clan Ribbcd horse mus;scl Rosy razor clan Smoo i-.h chione Washington cla:n

27 TABLE 14. Average Number of Fishes Captured for Resident Fish Species by Bag 1/21 Seine for Outer Bolsa Bay, Inner Bolsa Bay and South Bolsa Slough.-- Fish Namc Average Nunher of Species Captured -- - Outer Bolsa -- ~ a ~?---- Inner / Bol-sn Bay.?/ South Golsa slougq Arrow goby Bay pipef ish California killifish Deepbody anchovy Diamond turbot Longj aw I P L sucker ~ ~ Round stingray Sh~dobr goby Shiner suy-iperch Staghorn sculpin Striped mullet l'ilapia Topsrnel t Yellowfin goby 11 - Numbers were calculated by taking total nun~bcrs of each species captured and dividing this n ~ ~ b by e r total nuinbcr of bag seine sets. \\?hen the rlunber of a species capi-ured uas over 500 for a set, then 500 was used for totrl number captured for thal: sct - 2 / Assumes rill Fishes equally vulnerable to bag seine 3 / - If numbcr is blank, fish not considered a resident for this area

28 abundant fish was killifish in inner nolsa Bay and south Golsa slough (Table 14). Gill nets were used only in inner Bolsa Bay. The most ah-lndant fish captured tias topsmelt (Tab1.e 15). -- Recor.mendations - on Water Management Przctices --- as Co~ccrns Fishcs and Bivdxles in Inner Bolsa Bav and South Colsa Slocch Since the nuiiil~er of fish and bivalve species continues to increacc, we rccormcnd thet tt.70 cul-vcrts be left open for tidal flooding and flush<.::g. TliLs 1,:n'icr exchcingr- rate with two cul.vei-ts open eppears to be bcl?-...ficial to 11 species of fishes ~,~h-icll use Bol.sa Eay and south Bolsa slou~h for syawcing and nurfery grounds. Recrul.tnent of bivalve species increased in inner Bolsa Bny with t ~ culverts o open, and juveniles of these. clan1 species were able to survi~~e i.11 this a.rea. Although we do nct have any concl-et.~ bio1c:;icnl date thst tt~o culverts open rca;;irr,i.zes fish populations or biomass preyed upon by birds; it has b~cn observed that piscivorous birds are higllly successful in capturing various species of fishes, and the numbcr~ of these birds using inner Bolsa Bay 3-nd south Eolsa slough has increcsed signific~ntly (IIarold Xovick, Wildlife Manager-Biologist, Calif. Dept. Fish and Game, pers. cozmun.). Project Reco~~c~ucndations The number of spccies of fishes and bivalves continued-to increase in inncx Bolsa Eay axd south Bclsa slough during Phase I when our sampling ended in August We recomie~ld that car~lpling of fishes and bivalves continue in Eolsa Chica Mlrsh until the numbers of new species found levels off. We recoii1mer.d also that sampli-ng should be cor.cluctc.d on any new areas opened to tidal sction within the C01sz Clzica Marsh.

29 TABLE 15. Average?:umber of Firh Captured for Resident Fish Species by Gill Net for Inner Bolsa B~~L/. Fish Name Bay pipefish 2-I California lcilli fish Diamond turbot Longj aw rr,udr;uclcer- 21 Round st ingray Shadow gobyz1 Shiner surfperch Staghorn sculpin Striped niullet ~ila~ia.?l Topsmelt Yellowf in goby Average Nusilbcr of Species Captu-red in 1:nner Eel-sa Bay Numbers were calculated by taking total numbers of each specjes captured and dividing this number by total number of gill net sets 2 1 Species not fully vulnerable to gill. net Species vulnerable t:o gill net, but not captured

30 Appendix 1. Con-~~on Fish Nanics with Equivalent Latin Scientific Name. Scientific Name Arrow goby Bay pipcfish Black croaker Calilornia corbina California halibut California killifish Cheekspot goby Deepbody anchovy Diamond turbot Giant kelplish Goldfish Grey snoott!hound Jacksrrelt Longj aw mudsccker Northern anchovy Pacific bonito Qucenf isti Round stingray Shedow goby Shiner surfpcrch Shovelnose guitarf ish Slough anchovy Specklefin midshipnan Staghorn scul pin Striped bass Striped mullet Tilapia Topsmelt \hi te croaker Pellowf in croaker Yello:c.fji~ goly Cleve landia ios Cheilotrena saturnwn SynUmat3zzis Zeptor3qr,chz;s?~lenticirr7zus u~zdulattls ParaZi.c3zt3zys ca Zifomzicus FunduZz4s parvipi.tlnis Ilpnus gi Zberti Anchoa compressa Hypsopsetta $uf;tuzata Ue terosticllus rostrattis Carassi7~s auratus Muste lus californicus Atherinopsis ca li.j~rr?,i--~ bt.sz~ ' GiZZiclzthys mirabizis Engrau Zis r;rordax Sardg chizieizsis Ser?:phzcs po Zitus Urolophus hazleri QuietuZa y -cauil'a CyrnatogasCer aggregate Hhinobatos proczzizictz~s Axchoa de Zicatissima Porichtl:ps 7:;:jriagter Leptocottus o.i2?natz4s Roccus saxatilis Mug.?: Z cepha Zus Ti Zapia nlos sumbica Ati~er~i?zops affinis Ihribrixa roncador Acanthogobi-us f 2avin;o.l-24s Gsny onemus Zinsatzcs

31 A~~~endix 2. Common Bivalve Names with Equivalent Latin Scientific Name. Common Name Banded chione Bay mussel Rentnose clam California jackknife clam California rnac tra Common littleneck clam Cooperella cl an1 Egg cockle Gaper clam Mud piddock Native oyster Nestling clain Ribbed horse mussel Rosy razor clam Smooth chione IJashington clam Sc.icrlt i fic N'me Chime cazifo~izierzsis b1zjtizus eduzis Efae01~7a xasz~ta Tage 2v.s ca Zij'crniaizus i4uctra cali fomria Proto thaca stcmii?ea CoopereZ Za s?l7/dcctphana Lae o-lcar~diwn su1.s triatzm Tresus nuttnlli Barwen subtrzcii~ata 0s trca Zurida Petricola ea1 ifomzier,sis Geuke~is?:a ier:issa SG Zen roscceus Chionc fzuctif~(iya Saxin'crirzis r,v.ttaz Z i

32 LITERATURE CITED Fel.dmeth, Robert C. and Associates Survey of inner and outer Bolsa Bay: recolonization and recruitment study. Ecological Ke- search Services: Clarelnont, CA IIa,rdy, Robert A The marine enviromi~nt: upper Newport snd Sunszt Bays, Orange County, Calif 0rni.a. Calif. Dept. of Fish and Game, Plar. Res. RP~. Ref. KO p. Knaggs, Eric 11. and R. E. Ilall Fish and. bivalves 21: Bolsa Chica llarsh re-establishment project. Progress report I. Calif. Dept, o-f Fish acd Game, liar. Res. Admin. Rcpt. No p.. 198Ob. E'i.sh :VLI~ bl.vclvcs at Eolsa Chica Pizrsh re-e~tablishi~ent project. Progress report 11. Ca1f.f. Dept. of Fish acd Gane, Mar. Rcs. Adnin. Rcpt. No p EOc. Fish 2nd bi.velves at Eolsa Cllice Ilarsh re-es'iablf.sllrr.cnt project. Progress report 111. Calif. Dept.. of Fish and Gme, Kar. Res. Admi.n. Kept. NO p. Miller, Daniel J. and R. N. J,ea Guide to the coastal marine fishes of Ca.lifcrnia. Calif. Fish and Game, Fish Bull., (157) :

33