CONSERVATION BIOLOGY PROGRAM

Summary Report: Green , Longfin Smelt, and Dredging Operations in the San Francisco Prepared for U.S. Army Corps of Engineers by Bronwen Stanford, Kat Ridolfi, and Ben Greenfield San Francisco Estuary Institute

CONTRIBUTION NO. 598 SAN FRANCISCO ESTUARY INSTITUTE 7770 Pardee Lane, Second floor, Oakland, CA 94621 DECEMBER p: 510-746-7334 (SFEI), f: 510-746-7300, www.sfei.org 2009 Thisreportcanbecitedas:Stanford,B.,K.Ridolfi,andB.Greenfield,2009.Summary Report:GreenSturgeon,LongfinSmelt,andDredgingintheSanFranciscoEstuary. PreparedfortheU.S.ArmyCorpsofEngineers.SFEIContribution#598.SanFrancisco EstuaryInstitute,Oakland,CA. TABLEOFCONTENTS

1.ABSTRACT...... 1 2.ACKNOWLEDGEMENTS...... 2 3.INTRODUCTION...... 3 4.GREENSTURGEON...... 6 4.1.Managementhistoryandcurrentstateofknowledge...... 6 4.1.1.Greensturgeonbiologyandecology...... 8 4.1.2.Impactsofdredging...... 10 4.2.Concernsofstakeholders...... 14 4.3.Futureresearchandrecommendations...... 14 5.LONGFINSMELT...... 17 5.1.Managementhistoryandcurrentstateofknowledge...... 17 5.1.1.Longfinsmeltbiologyandecology...... 17 5.1.2.Impactsofdredging...... 19 5.1.3.Otherpotentialthreatstolongfinsmelt...... 22 5.2.Concernsofstakeholders...... 23 5.3.Futureresearchneeds,andpotentialsolutions...... 24 6.NEXTSTEPS...... 26 7.REFERENCES...... 28 1. ABSTRACT

In2009,CaliforniaDepartmentofFishandGameCommissionlistedlongfinsmelt (Spirinchusthaleichthys )asthreatened,andNOAAformallyadopted“take”provisions forgreensturgeon( Acipensermedirostris Ayres).Thesechangesinthemanagement status,andassociatedpermittingissues,havepromptedrenewedinterestamongLTMS participantsinthemanagementofthesenativefish.Inresponse,LTMSheldsymposia onDecember2and3,2009,toreviewandconsiderthescience,management,andpolicy relatedtodredgingactivitiesandthesespecies.Aprimarystressortobothspeciesis reductionofappropriatehabitat,duetowaterdiversionactivitiesandotherbasin-scale modificationsinwaterflow.Localstudiesofdredginghaveshownlittleevidenceof directentrainmentforeitherspecies,andthefrequencyofencounterwithsitesof dredgingactivityislikelytobeverylow.Nevertheless,spatialandtemporalpatternsof populationmovementsandreproductiveactivityvaryfromyeartoyear,makingit difficulttoemployanenvironmentalworkwindowsapproach.Availableinformationis limitedonotherdirecteffectsofdredging,includingsedimentcontamination,habitat modification,andunderwaternoise.Indirecteffectsduetomaintenanceofactive navigationchannelsposepotentialconcerns.Inparticular,introductionofinvasive species,andmortalityduetopropellerstrikes,bothwarrantattention.

Asafollowupsteptothesymposia,werecommendthatLTMShostaworkshoptargeted towardsspecificLTMSmanagementneedsforgreensturgeonandlongfinsmelt.The workshopshouldincludeLTMSparticipants,thescientiststhatpresentedatthe symposium,anddredgingoperators,andcouldfocusontheintegrationofcurrent researchfindingsintotoolsthatwouldbeusefulformanagers.Appropriatetoolsfor considerationincludepredictiveordescriptivemodelsofspeciesdistribution,andof potentialimpactsofvariousdredgingactivities.Thereshouldalsobeconsiderationof managementapproachesthatbroadlyaddresstheprimaryecosystem-levelstressorsfor greensturgeonandlongfinsmelt,ratherthanemployingsmallscaleproject-level mitigation.Inparticular,anintegratedregionalrestorationandmonitoringprogrammay bethemosteffectiveapproachtoimprovethehealthofthespecies.

1 2. ACKNOWLEDGEMENTS

WethankChristineWermefordevelopingbackgroundmaterialandconceptsusefulin developmentofthisreport.JoanneCablingandLindaWanczykassistedwithgraphic design,includingthereportcoverpagegraphics.Theconferenceplanningcommittee, includingBillBrostoff,DavidWoodbury,PeteLaCivita,andGeorgeIsaac,provided conceptualguidanceandrecommendationsondevelopmentoftheconferenceprogram andcontent.ConstructivesuggestionswerealsoprovidedbyBrendaGoeden,Ellen Johnck,JessicaHamburger,andBrianRoss.Theresearchsummariesinthisreportwere derivedfromthepresentationsprovidedbyPeteKlimley,MikeThomas,AlexHearn, CynthiaFowler,MikeParsley,AndrewCohen,StephaniaBolden,DavidWoodbury,Josh Israel,DougClarke,TracyCollierRandyBaxter,JimHobbs,JonathanRosenfield, JordanGold,JenniferDeLeon,JohnZentner,andBrianSwedberg.Readersare encouragedtoconsulttheoriginalpresentationsforfurtherinformation,availableonthe webat http://www.sfei.org/cb/greensturgeon .Wealsothankthestakeholderparticipants fortheirinputatthesymposium:AnneWhittington,J.T.Wick,DavidWoodbury,Tom Gandesbery,LenCardoza,B.K.Cooper,andRainerHoenicke.Constructivereview commentsonpreviousdraftsofthisreportwereprovidedbyThomasJabusch,Rainer Hoenicke,BillBrostoff,MikeParsley,AndrewCohen,JoshIsrael,andDavidWoodbury. ThisworkwasfundedbytheU.S.ArmyCorpsofEngineersLTMS.

2 3. INTRODUCTION 1

TheLong-TermManagementStrategyforthePlacementofDredgedMaterialintheSan FranciscoBayRegion(LTMS)providesacooperativeframeworkformaintainingthe navigationchannelsoftheSanFranciscoEstuaryinaneconomicallyand environmentallysoundmanner.LTMSisanongoingcollaborationofmultiple participants 2.

Inordertogainabetterunderstandingofhowdredgingimpactstwospeciesofconcern, NorthAmericangreensturgeon( Acipensermedirostris Ayres)andlongfinsmelt (Spirinchusthaleichthys ),theU.S.ArmyCorpsofEngineers(USACE)fundedtheSan FranciscoEstuaryInstitute(SFEI)toholdtwosymposiatoevaluateanddisseminatethe latestavailableinformationonthesespecies.Theobjectivesofthesymposiawereto:  Disseminatecurrentknowledge,  Reviewguidelinesneededtomanagethesespeciesandcomplywithrelevant regulatorymandates;and  Developstudyplansforfurtherwork.

ThesymposiawereheldonDecember2and3,2009,inOakland,CA,withoneday dedicatedtoeachspecies.Therewereover100participants,includingscientists, regulators,representativesfromthedredgingcommunity,andotherinterestedparties. Thesymposiaalsoincludeddiscussionsofthevariousmanagementoptionsforthese specieswithrespecttodredgingoperationsintheregion,suchasthedredgingwindow policy.Thisbriefreportsummarizesthemajorfindingsanddiscussionsofthesymposia, includingthecurrentstateofknowledge,managementhistoryofthespecies,potential impacts(bothdirectandindirect)ofdredging,prioritiesandissuesidentifiedby stakeholders,andfutureresearchrecommendations.

Inthepastfewyears,decliningpopulationsofgreensturgeonhaveincreasedawareness ofthespecies,andresultedinlocalresearchstudies,includingbothpublishedliterature andunpublishedstudies(Armoretal.2006,Klimleyetal.2007).Thishasincluded taggingstudiesperformedbyCaliforniaexpertsinthefield,fundedbyLTMS.The southerndistinctpopulationsegment(DPS)ofNorthAmericangreensturgeon (Acipensermedirostris Ayres)waslistedas“threatened”byNOAAFisheriesunderthe FederalEndangeredSpeciesAct(ESA)in2006.Threeyearslater,inMay,2009,NOAA Fisheriesproposedarulingtoapply“take”provisionsforthispopulation.Green

1 ThisIntroductionispartiallybasedonpriorprojectdocuments,includingtheprojectConceptProposal, draftedbyChrisWerme,anindependentconsultant,andtheSFEIresponsetotheprojectRFP 2 AgencyparticipantsincludetheNationalOceanicandAtmosphericAdministration(NOAA)National MarineFisheriesService(NOAAFisheries),theCaliforniaDepartmentofFishandGame(CDFG),the U.S.ArmyCorpsofEngineers(USACE),U.S.EnvironmentalProtectionAgency(EPA),Bay ConservationandDevelopmentCommission(BCDC),StateWaterResourcesControlBoard(SWRCB), andotherlocalagencies.Stakeholderparticipantsincludedredgingcontractors,municipalitiesandprivate entitiesthatperformdredgingactivities,andprivateandpublicentitiesthatprocuredredgedsedimentsfor habitatrestorationandotherbeneficialreuses.

3 sturgeonsoutsideoftheBay-Deltaregionhavealsosufferedpopulationdeclines.For example,theyarelistedas“rare”inCanada(Moyle2002).

Lessresearchhasbeenconductedonlongfinsmelt,thoughCDFGsurveydataindicate thatthelongfinsmelthasdeclinedsubstantiallysincethe1980s(RosenfieldandBaxter 2007,CaliforniaDepartmentofFishandGame2009).InJanuary2009,theCalifornia DepartmentofFishandGame(CDFG)listedlongfinsmeltas“threatened”underthe CaliforniaEndangeredSpeciesAct(CaliforniaDepartmentofFishandGame2009).

TheCaliforniaESA(CESA)isverysimilartothefederalESAinmanyways(e.g.the listingprocessandthedefinitionoftake)althoughtherearesomedifferences.Thestate ESAprotectsonlyspeciesandlimits“take”withintheboundariesofthestate,whilethe federalESAalsoprotectsdistinctpopulationsandcanlimittakewithinadefinedareaof criticalhabitatforthepopulation.CESAismorestringentthanthefederalESAintwo keyways:1)whilespeciesareonthecandidatelist,theyareaffordedfullprotectionofa listedspeciesandtakeisprohibited,and2)fullmitigationfortakeisrequiredforlisted species.ThismeansthatundertheCESA,ifanactivitywouldresultinthetakeof10 ,anactionthatwouldimproveconditionstoreplacethose10fish(throughhabitat improvement,forexample)isrequired.

Previousreviewsidentifymultipleprobablethreatstolongfinsmeltandgreensturgeon populationsinCalifornia,includingreductioninDeltaoutflows,entrainmentviawater diversions,elevatedwatertemperatures,climaticvariation,exposuretotoxicsubstances, ,poaching,andbothdirectandindirecteffectsduetoinvasivespecies interactions(Moyle2002,Adamsetal.2007).Therelativeimpactsofthesemultiple factorsonsurvivalandrecruitmentofgreensturgeonandlongfinsmelt,andthe relationshipsofthesefactorstodredgingactivitieshavereceivedlittleattention.

Greensturgeonareatfurtherriskofpopulationdeclinesduetotheirlonglifespan,late maturity,reducedhabitatsize,andlossasbycatch.Theirlifehistoryandlatematurity meanthatthelossofevenafewspawnerscouldbeharmfultothepopulation.Green sturgeonareoftencaughtasbycatchduringrecreationalandcommercialharvestingof whitesturgeon(Adamsetal.2007).RisktotheSacramentoRivergreensturgeon populationisparticularlyseverecomparedtothatoftheNorthernDPSintheKlamath Riverbasin,asspawningareasabovewaterdiversiondamsarenowinaccessible,when historicallysturgeonmayhavebeenabletoaccesstheentireSacramentoRiversystem upstreamofdams(includingtributariessuchastheMcCloud,PitandFeatherRivers; Adamsetal.2007).

Therecentchangesinlistingstatusofgreensturgeonandlongfinsmeltto“threatened” areimportanttoLTMSparticipants.Thisnew,moreprotectedstatushasimplicationsfor dredgingoperationsanddredgedmaterialplacement.Millionsofcubicyardsaredredged fromSanFranciscoBayannuallytomaintainthenavigationchannelsneededtosupport theshippingindustryandrecreationalboatingactivities.Potentialdirecteffectsof dredgingonfishesincludeinterferencewitheggattachment,fertilization,orrespiration; exposuretochemicalcontaminantsinsuspendedsediments;entrainment;effectsto

4 survivalandmovementthroughmultiplelifestages;andbehavioralimpactsonadult spawningactivity(WilberandClarke2001).Dredgingcanalsoaffectfishesbyindirect mechanisms-intermediatepathwaysresultingfromecosystemchangesorhuman activities.Forexample,largecommercialvesselactivityisfacilitatedbymaintenanceof navigationalchannels.Thesevesselscanbevectorsforspeciesintroduction,andcan injurefishesordisturbtheirmovementsorbehavior.

Giventhethreatenedlistingstatusofthesespecies,andconcernabouttheirlong-term populationviability,thereisaneedtoreviewandsynthesizethelatestknowledgeon theirpopulationbiologyandmanagement.

5 4. GREENSTURGEON

4.1. Managementhistoryandcurrentstateofknowledge InMay2009,NOAA-Fisheriesformallyadopted“take”provisionsforthethreatened southerndistrictpopulationofthegreensturgeon(FederalRegisterVolume74,Number 97,availableat http://www.nmfs.noaa.gov/pr/pdfs/fr/fr74-23822.pdf ).Thispopulation segmentincludestheSanFranciscoEstuary.Therecentprovisionspromptanadditional needforinformationaboutpotentialadverseeffectsthatdredgingactivitiesmayhaveon thespeciesandpossiblewaystoavoidorminimizethoseeffects.

CriticalhabitatforthisspecieshasbeendesignatedbyNOAAFisheries.Criticalhabitat includestheSanFranciscoBayandDelta,theSacramentoRiver,andwatersoffthe coastlinefromMontereyBaytotheStraitofJuandeFuca(Figure4.1).BrianRoss(EPA) andEllenJohnck(BayPlanningCommission)openedthesymposiumwithdiscussionsof theneedtodevelopnewstrategiesforthegreensturgeon.Protectionofgreensturgeon presentsanewchallengetostakeholdersbecause‘take’ofthisyear-roundBayresident cannoteasilybeavoidedthroughdesignatedworkwindows,unlikemanyotherprotected species(DavidWoodbury,NOAAFisheries).Stakeholders,includingLenCardozaand JayAch,agreedthatnewstrategiesandmorecleardirectivesareneededtohelpthem fulfilltheirresponsibilitiestobothcomplywiththeEndangeredSpeciesAct(ESA)and conductbusiness,whichincludesperiodicdredging.Inparticular,stakeholdersexpressed adesireforclearlydefined,predictableregulatoryrequirements.Suchrequirementswill enablethestakeholderstomeettheirESAresponsibilitiesandcontinuetoconduct maintenancedredgingtoprovideuninterruptedcommercialnavigation.

CynthiaFowler(USACE)describedthetypesofhydraulicandmechanicaldredgesthat areroutinelyusedinSanFranciscoBay.Shealsoprovidedanoverviewofthemany ongoingdredgingprojectsintheBay.Dredgedsedimentisgenerallydisposedofbyone offourmethods:1)disposalinoneoffourin-baysites;2)re-nourishmentofshorelines; 3)reuseforrestorationprojects;or4)disposalinanoffshoredisposalsiteinthePacific Oceanapproximately50milesoffshoreofSanFrancisco.Shedescribeddredgingasa “movingtarget”–theexactsitesandprojectsmaychangeeachyeardependingon shoalingpatterns,climaticvariation,andavailablefunding.Hermapssummarizedthe diverserangeoflocationsofdredginganddredgedmaterialsplacementactivity(Figure 4.2).

6 Figure4.1.CriticalhabitatforgreensturgeonextendsfromportionsofPuget Sound,,southwardtoMonterey.ItincludestheSanFranciscoBay- DeltaregionandtheSacramentoRiverandselectedtributaries(NOAAFisheries).

7 Figure4.2.Current(2008)dredgingactivityanddredgedmaterialplacementinSan PabloBay(Fowler).Thisisoneofmanygraphicswithdetailedinformation regardingdredgingactivitiesanddredgedmaterialplacementthroughouttheSan FranciscoEstuary.ThedatabaseisbasedonaGeographicInformationSystem (GIS),andisavailablethroughtheUSACE.

4.1.1. Greensturgeonbiologyandecology Dr.JoshIsrael(UC-Davis 3)presentedthecurrentstateofresearchongreensturgeon. Greensturgeonsspendmuchoftheiradultlivesincoastaloceans,returningtoestuaries beginninginlateFebruarytospawn(Figure4.3).Theymoverapidlyupriverduringearly springflows,spendingweekstomonthsintheSacramentoRiver(belowtheShastaDam) wheretheybroadcastspawnintoriverbenthos.Larvaedriftslowlydownriver,maturing toliveintheBayandDeltaforbetweenoneandfouryearsbeforeenteringthecoastal oceans.Thisperiodremainspoorlyunderstoodandindividualsvaryintheirtimeof residencewithintheEstuary.

3 CurrentaffiliationisU.S.BureauofReclamation

8 Figure4.3.Greensturgeonlifehistorycorrespondswithriverflowandsalinity. Adultsturgeonmoveupstreamtospawnperiodically(every1to4years)during largespringflowevents.Larvalsturgeonmovedownstream,anddevelopinto juvenilesinbrackishestuarineconditions(Israel).

Dr.PeterKlimley(UC-Davis)trackedmovementpatternsofsub-adultandadultgreen sturgeon,findingthattherearetwodifferenttypesofmovement:highlydirectional migratorymovements,whichoftenoccurclosetothesurfaceandwithinchannels;and non-directionalmovementalongthebottom,whichcanoccurinbothdeepwater channelsandshoals.Thisnon-directionalmovementisspeculatedtobeforagingactivity. Bothofthesebehaviorscouldputsturgeonatriskfromdredgingasnewlydredged channelsmayimpactwithin-channelmigration,anddirectentrainmentandsediment disturbancescouldinterferewithfeedingnearthebottom.

AlexHearn(UC-Davis)contributedinformationfromhistrackingstudyof300adult sturgeon,whichrevealedawidevarietyofbehaviors.Sturgeonweredetectedinboth shallownearshoreareasandchannels,andreturnedupstreamtospawnattimeintervals rangingfromonetothreeyears.Heindicatedthatgreensturgeonweremoreconcentrated neartheGoldenGateinthesummer,whileinwintertheyweredistributedmorewidely throughouttheEstuary.Healsofoundthatwhilesomeofthetrackedfishdidvisitfour dredgedsites,cumulativedurationofsitevisits(perfish)rangedfromlessthan30 minutestojustoverfourhours.

9 MikeThomas(UC-Davis)contributedadditionalresearchfromactivetrackingofthree juvenilegreensturgeons.Hefoundthatallofthefishusedthedeepwatershipping channel,butalsospentsignificanttimeoutsideofthechannel,andmayhaveshown preferencefornon-deepwaterchannelhabitats.

MikeParsley(USGS)presentedresearchdescribingtheuseofafine-scalepositioning systemtomonitormovementsofwhitesturgeonintheColumbiaRiverinareaswhere dredgingoperationsoccur.Hedescribedapatternofdailyverticalmigrationsinwhite sturgeon,asfishmovedfromdeeperwatersduringtheday,typicallywithinthe navigationchannel,toshallowerwatersoutsideofthenavigationchannelatnight.His analysisofthemovementsrevealedthatwhitesturgeonpreferredareaswithsome bedformhabitatforfeeding,possiblybecausethisroughsurfacecanprovidecurrent breakswithinahighenergyenvironment.Healsodividedwhitesturgeonindividualsinto twocategories,basedondispersaltendencies,whichhereferredtoasthe“homebodies” andthe“nomads.”Homebodiestendtoremainwithinalimitedareaovertimeandso couldpotentiallybemoredisturbedifforcedtomovebyadredgingoperation.Nomads spentlittletimeinanyoneareaandthusmaybemoreresilienttolocalizeddisturbance.

4.1.2. Impactsofdredging Speakerspresentedthecurrentstateofknowledgeontheimpactofdredgingongreen sturgeon,explainingthatmuchisstillunknown(Table4.1).Speakersvariedintheir ratingoftherelativeimportanceofpotentialdredgingimpacts,andemphasizedtheneed todifferentiatebetweentheimpactsfromdredgingformaintenanceversusdredgingfor newprojects(suchaschanneldeepening).Therearearangeofpotentialdirectand indirectimpacts,includingthefollowing:

Directeffects • Hydraulicentrainment • Contaminatedsediments • Sedimentresuspension(turbidity)andsedimentation • Underwaternoise • Changetohabitat-bedleveling Indirecteffects • Impactonpreybase • Shippropellerstrikes • Invasivespeciesintroductionsfromchangeinshippingpatterns(supportedby disturbancefromdredging)

DougClarke(USACE)outlinedtwomajorfactorstoconsiderinassessingriskofdirect entrainment,whichweretherateofencountersandtherateofdetrimentaloutcomesfrom encounters.Encounterrateisafunctionofthespatialdistributionandtemporalfrequency ofdredgingactivity,andthespatialandtemporalmovementpatternsofsturgeon.Rateof detrimentaloutcomesuponencounterdependsontheavoidanceandescapebehaviorof thefish(Figure4.4).JoshIsrael(UC-Davis)similarlyidentifiedthreespecificfish behaviorsthatwouldimpactriskfromdredging:orientationoffishincurrent,timeto

10 fatigue,andpositioninthewatercolumn.Understandingfishbehaviorssuchas swimmingcapacityandtendencytoswimintoorawayfromthecurrent(forgreen sturgeon)wouldhelpusassessrisk.

TracyCollier(NMFS)discussedthepotentialforcontaminatedsedimentstocausedirect impactstofishvialiverdisease,impairedreproduction,lossofimmunesystemfunction, andreducedgrowth.Hesuggestedthattherearecontaminantthresholdsabovewhichthe proportionofindividualsaffectedgreatlyincreases(e.g.,impactstoflatfishincreaseat 1000ng/gdryweightPAHs).Developmentaleffectscouldbeofparticularconcernfor greensturgeonbecausetheyproduceeggswithunusuallylarge,fattyyolks,whichcould passonhighconcentrationsofcontaminantsfrommothertooffspring.Additionally, elevatedcontaminantscouldindirectlyaffectgreensturgeonbychangingpreybiomass andabundance.Somefish(e.g.,,Pacificherring,shinersurfperch,staghorn sculpin,andSacramentosplittail)currentlyexhibittoxicologicalresponsesat environmentallyrelevantconcentrations.

AndrewCohen(CenterforResearchandAquaticBioinvasions[])reviewed potentialmechanismsbywhichdredgingactivitiesmayleadtoexoticspeciesimpactson greensturgeon.Navigationalmaintenancedredginganddevelopmentofnewnavigational channelsmaintainstheabilityforcommercialvesselsfromdistantportstoutilizeSan FranciscoBayports,andthisshippingactivitycanresultintheintroductionoforganisms carriedinthewaterinballasttanksandseachests 4,orattachedtovesselhulls.Dredging activitiesmayalsodisturblocalenvironmentsinwaysthatmakeiteasierforexotic speciestobecomeestablished.Impactsongreensturgeoncouldarisethroughpredation, competition(suchasfromexoticsturgeonspeciesintroducedaseggsorlarvaeinballast tanksorseachests),alterationoffoodwebs(arecentexampleofsuchalterationinthe BaybeingfromtheAsianclam Corbulaamurensis ,introducedinballastwater),changes incontaminantpathways(suchasseleniumaccumulatedin C.amurensis andingestedby sturgeon),introductionofdiseasesorparasites(includingfishvirusesthatcanbecarried inballastwater),introductionofharmful,bloom-formingalgae,orbyfoulingoffish passageorsalvagefacilities(suchasbyChinesemittencrabs,zebraorquaggamussels, ortheecologicalsimilargoldenmusselfromAsia,allofwhichhavebeenintroduced acrossoceansinballastwater).

Propellerstrikesareanotherpotentialindirectimpacttogreensturgeon.Aswithexotic species,dredgingtomaintainanddevelopnavigationalchannelsenableslarge commercialvesselstoentertheEstuary.Aslarger,higherpoweredvesselsenterSan FranciscoBay,theriskofpropellerstrikesmayincrease.DougClarke(USACE)found traumain2%offishcaughtinanentrainmentstudyontheMississippiRiver.LikeSan

4 Seachestsareshipcompartmentsthatarelocatedimmediatelyinsideacargoship’shull.Theyreceive waterpassivelyfromtheoceanthroughslottedholes1-2cmwide,whichisthenpumpedtotheballast tanks.Smallfishandotherorganismshavethepotentialtomovefreelybetweenseachestsandthe surroundingwater.Thetransportoforganismsinseachestsisnotdirectlyregulated,andmostmechanisms usedorproposedforreducingthetransportofliveorganismsinballasttankswouldhavelittleoronly limitedeffectonorganismstravelinginseachests(Cohen).

11 FranciscoBay,theMississippiRiverisasystemwherestakeholdersmustbalancethe needsofshippingandofprotectingnativefinfish.

MikeParsley(USGS)discussedresearchontheresponseofwhitesturgeontodredging operations.Inparticular,thefishdidnotdisperseduringdredgingoperations,butbecame moreactive.Thisincreasedactivitycouldhaveresultedfromeitherstressorincreased foragingactivity.Parsleyandcolleaguesalsofoundthatwhitesturgeonremainedina disposalsitethroughoutaseveralhoursedimentdisposaloperation.

StephaniaBolden(NMFS)discussedherworkwithAtlanticsturgeoninFlorida,and identifiedmodificationofcriticalhabitatasthemostpressingconcern.Shenotedthatthe typeofdredgemadeadifferenceinentrainmentrates.Hopperdredgesgenerallyresulted inthemosttake,andclamshelltheleast.Ms.Boldenpointedoutthatevenclamshell dredgesresultedinsomemortalitytosturgeon,thoughtherateswererelativelylow.

EntrainmentRiskforSturgeon

Figure4.4.Flowchartconceptualmodelofentrainmentriskforsturgeon(Clarke). Entrainmentriskwilldifferandmaybemodeleddependingonrheotaxis (orientationtowardscurrent),escapespeed,andstation-holdingbehavior.

12 Table4.1 . Typesofpotentialdredgingeffectsongreensturgeon,currentknowledge regardingeffects,andpotentialfuturestudiesthatwillprovidemoreinformation abouttheeffects. Effect Currentknowledge Potentialfuturestudies Direct Entrainmentratesappeartobegenerally Directassessmentofentrainment entrainment low rates,particularlyfordifferent dredgingtypes.Chamberstudieson swimmingcapacityandcurrent orientationpatterns,extrapolatedwith entrainmentmodelstoassessrisk Contaminated Sedimentcontaminationiselevatedin Specificvulnerabilityofsturgeonin sediments someregionsoftheBay.Somefish differentlifestagestosediment speciesexhibittoxicologicalresponsesat contamination environmentallyrelevantconcentrations. Thereisthepotentialforsturgeontopass onhighlevelsofcontaminantstoyoung Sediment Sturgeonappeartobeundisturbedbyhigh Assessimpactofsuspendedsediment resuspension concentrationsofnaturally-produced resultingfromdredging(mayhave suspendedsediment.Therefore,adverse highlevelsofammoniaorhydrogen effectsofsedimentresuspensionare sulfides).Lowerpriorityforthis unlikely species Underwater LittleknownChamberstudiesonbehavioral noise responsetosonicexposure,e.g.,using soundexposureasamanagementtool todispersesturgeonandreducedirect entrainment Changeto Sturgeonmaypreferdeepwaterhabitats, Habitatpreferencestudies,including habitat(bed orinhabitbothdeepwaterandshoals. synthesisofcurrenttrackingdatato leveling) Habitatmodificationcouldinterferewith inferhabitatpreferences.Habitat dailyverticalmigrations,andresultin assessmentstudiestoidentify lossofbedformhabitatstructural importantareas complexity Impactsto Introductionofinvasivespeciesor Dietarystudiesonpreybase;impact preybase contaminatedsedimentscouldharmprey ofdredgingalterationtoprey base productionareas ShipstrikesMultiplefishspeciesinotherregions Specificrisktogreensturgeon. encountershippropellers,sometimes Methodscouldincludenet resultinginmortalinjury.Riskmay deploymentbehindcommercialvessel increasewithhigherpoweredvessels. propellers,thoughthesestudiesare Substantialcommercialboatingactivity difficulttoperform (e.g.,cargoshipping)presentsapotential hazardofshipstrikes Increased Possiblenegativeimpactsthrough Methodsofreducingspeciesinvasion, introductionof introducedparasitesandcompetitors includingmanagementofseachests invasive species Impacton Littleisknownaboutthebehaviorofvery Notknown–larvalstagesnotlikely larvaland youngsturgeonandsusceptibilityto presentinSFBay juvenilelife dredgingimpacts stages

13 4.2. Concernsofstakeholders Astakeholderpanelexpressedconcernsandengagedindiscussionwiththescientistsand regulatorsregardingtheongoingchallengesofmanagingdredgingwithgreensturgeon. ThepanelwascomposedofAnneWhittington(PortofOakland),LenCardoza(Weston Solutions),DavidWoodbury(NOAAFisheries),andTomGandesbery(StateCoastal Conservancy).Stakeholdersinthedredgingcommunityexpressedconcernsaboutthe impactsoftherecentlistingofgreensturgeononcommerce,recreation,andjobs.They emphasizedthattoeffectivelyplanandruntheirbusinesses,dredgersneedtoknowwhat theymustdotominimizeandmitigateimpactsongreensturgeon.Stakeholdersare interestedinexploringothersolutionsforthisspecies.Addinganadditionalwork windowtothealreadycomplicatedsystemofoverlaidworkwindowswouldbe challenging.Theyalsoexpressedinterestinalargerprogrammaticsolutionthatcould takebothindustryneedsandtheneedsofthespeciesintoaccount.Lastly,stakeholders discussedtheneedforcontinuedandimprovedcommunicationbetweenresourceand federalagenciesandpermitapplicants.

4.3. Futureresearchandrecommendations Duringpresentationsandscientistdiscussion,severalsuggestionsforfutureresearch relevanttodredgingoperationsemerged.Theserecommendationsfocusedongathering informationtoenablemodelingofthegreensturgeonlifehistoryandtheimpactsof dredgingonthislifehistory.Thiswouldallowmanagerstoidentifythemostimportant impactsandeffectiveformsofmitigationforsturgeon.Conceptualmodelssuchasthose developedbyDRERIP(DeltaRegionalEcosystemRestorationImplementationPlan) couldbehelpfulforprioritizingresearchonfactorslimitingrecoveryofgreensturgeon populations(Figure4.5).Forexample,ifexposureoffisheggsandlarvaetopollutants impactsthepopulationdisproportionately,ESAmitigationactionsmayfocusonreducing suchexposure.

Panelistsrecommendedstudyingbasicaspectsofsturgeonlifehistoryandecologythat couldaffectriskfromdredging.Theyalsorecommendedfurtherevaluationofthe relativeriskassociatedwithspecificdredgingimpacts.Basicstudyrecommendations included:

1. Additionalstudyofjuvenilelifehistoryandmigrations. Littleisknownabout juvenilemovement,distribution,andconsequentpotentialexposuretodirect hazardsfromdredgingandotherhumanactivities.Suchstudiesaretechnically difficultbecauseoftherelativelysmallsizeofjuveniles,andlowabundancein comparisontootherspecies. 2. Behavioralstudiestoindicatefrequencyandhazardofdredgingexposure. Evaluationoffishbehaviorwasidentifiedasameanstobetterestimatethe encounterrateandprobabilityofadverseimpactsuponencounter.Abetter understandingoffeedingpatternsandhabitatpreference(e.g.,deepwaterchannels vs.shallowshoals)wouldaidindeterminingthelikelyfrequencyofdredge encounters.Thepotentialforentrainmentorinjurycouldbeevaluatedbasedon timetofatigueandonfishorientationandpositioninthewatercolumn

14 (rheotaxis).Thesefactorscouldbecombinedintoquantitativemodelstoestimate theexpectedrateofentrainmentandotherdirectdredgingimpacts.

Figure4.5.Transitionmatrixshowingfactorsaffectingsurvivalforgreensturgeon (Israel).Dredgingislistedasoneoffourdirectimpactsofhumanactivity(upper left)thatmayimpairsuccessfulspawning.Understandingoftheimpactofdredging andotherfactorsislimited,asindicatedbyreddottedarrows.

TheSciencePanelindicatedthatthefollowingpotentialthreatsmeritstudyand comparisontodeterminerelativerisk:

1.Directentrainmentfromdredging,includingcomparisonamongdredgingtypes 2.Shipandpropellerstrikes 3.Impactofinvasivespecies

15 4.Impactoftoxicchemicalsandlevelofchemicalcontamination 5.Habitatmodification  Effectofalterationstobenthiccommunityonjuveniles  Impactofalteredchannelsonmigrationpatterns–greensturgeonappearto usedeepwaterchannelsformigration 6.Interactionofgreensturgeonwithdredgingsites  Researchonafewindividualsindicatesthatfishpassthroughdredgingsites quickly(Hearn),thoughadditionaldatawouldbeusefultodeterminingif thisistrueofthelargerpopulation  Fishappeartouseshippingchannels(Thomas),butitisuncleariftheyshow apreferenceforshoalhabitats

Finally,somesuggestedactionitemsforLTMSincludedthefollowing;however, prioritizationofthesetopicswasnotaddressed 5:

1.Considerdevelopinglimitedworkwindows.Thereissomeresearchshowing greensturgeonmovefurtherdownstreamtowardsthecentralBayinwinter (Hearn),movetodeeperwaterindaytime(Parsley),andmayseekconstantwater temperatures.Allofthisinformationcouldbeusedtodevelopanewtypeofwork window. 2.Considertheimportanceofusingcorrectdredgingtechniquestominimize impactsongreensturgeon,e.g.preventdredgedragheadfromlosingcontactfrom bottom. 3.Reconsidersedimentdepositionandthemanypotentiallyproductiveusesfor dredgedsediment. 4.Ensurethatdepositionisnotdestroyinggreensturgeonhabitat,e.g.,consider spreadingthinly,overtime,andawayfromkeyhabitats(Bolden). 5.Regulateseacheststocontrolinvasivespecies. 6.Investigatemethodstomovefishoutofanareaofinterestusingnetsorsounds beforedredging(Bolden).

5 Theneedforfutureactivitiestoprioritizeamongandcriticallyevaluatethesesuggestionsisdiscussedin Section6.NextSteps.

16 5. LONGFINSMELT

5.1. Managementhistoryandcurrentstateofknowledge Longfinsmelt( Spirinchusthaleichthys )isanestuarine,anadromousspecies.OnMarch4, 2009,theCaliforniaDepartmentofFishandGame(CDFG)listedthelongfinsmeltas threatenedundertheCaliforniaEndangeredSpeciesAct(CESA;FishandGameCode§§ 2050etseq.).TheU.S.FishandWildlifeServicehasthusfardeclinedtolisttheSan FranciscoEstuarypopulationoflongfinsmelt.InNovember2009,asuitwasfiledbythe CenterforBiologicalDiversity,TheBayInstitute,andtheNaturalResourcesDefense Counciltochallengethefederaldecisionnottolistlongfinsmelt.TheFishandWildlife Serviceiscurrentlyreviewingavailableinformationtore-evaluatewhetherlistingis warranted(Rosenfield).Aswiththegreensturgeon,researchonthisspecieshasbeen limiteduptothepresent.

EllenJohnck(BayPlanningCoalition)openedthesymposiumwithherobservationon thechallengeandimportanceofdevelopinganewmanagementstrategyforathreatened species.JenniferDeLeon(CDFG)providedbackgroundinformationonthestatelisting processandlegalstatusoflongfinsmelt.Sheemphasizedthatmoreclaritywillcome withtimeasscientistsandregulatorsdevelopabetterunderstandingoflongfinsmelt.

5.1.1. Longfinsmeltbiologyandecology JonathanRosenfield(TheBayInstitute)andRandyBaxter(CDFG)presented informationonthelifehistoryoflongfinsmelt.TheSanFranciscoBayisatthesouthern extremityofthespawningrangeforlongfinsmelt,whichextendsfromSanFrancisco BaytoPrinceWilliamSound,Alaska(Figure5.1).Historically,thisspecieswasfoundin threeestuariesinCalifornia:theSanFranciscoBay-DeltaEstuary,HumboldtBay,and theKlamathRiverEstuary.Atthistime,thelargestandsouthernmostself-sustaining longfinsmeltpopulationisintheSanFranciscoBay-DeltaEstuary.Itislikelythatthe twonorthernpopulationsareextinct,andotherlocations,suchastheRussianRiver,do notsupportaself-sustainingpopulation.

Longfinsmeltspawnanddieintheirsecondyear,creatingtworeproductivelydistinct populationswithinanygivenregion.Theyspawnattheinterfacebetweenfreshand brackishwater,likelybetweenDecemberandMarch.Spawningsitesdistributearound X2(definedasthedistancebetweentheGoldenGateandwherethelowsalinity(2ppt) zonestarts),shiftingupstreamanddownstreamwiththechangeinfreshwaterinputsfrom theDelta.Youngexistasyolksaclarvaeforonetotwoweeks,movingdownstreamwith thecurrent.

Asadults,longfinsmeltoccupymuchoftheBaybutappeartolimittheirdistributionto betweenSuisunBayandCentralBayinthesummer,perhapsduetotemperature.More researchisneededonhabitatpreferences,butlongfinsmeltappeartobemoreabundant indeepwaterchannelsthanshoals.

17 Dr.JimHobbs(UC-Davis)presentedresearchshowingthatsmeltlarvaeappeartouse depthinthewatercolumntostayinthemoderatelysalineproductivezoneassociated withX2(Figure5.2).Historically,thispositionedthelarvalsmeltinareasofhigh productivityandfoodavailability.Modern-daychangestotheDeltaappeartohave impairedtheirabilitytoresideintheseconditions.

Figure5.1.ThehistoricspawningrangeoflongfinsmeltextendsfromSanFrancisco BaytoPrinceWilliamSound,Alaska(Rosenfield)

DuetohydrologicalmodificationoftheDeltaandCentralValleywatersheds,decreased freshwaterflowshavemovedthefresh-saltinterfaceupstreamtoshallow,narrow reaches.Thishasreducedstratification,consequentlyreducingtheabilityoflongfin smelttocontrolpositionbyverticalmovementinthewatercolumn.Inanotherstudy

18 usingotolithbiochemistry,Dr.Hobbsfoundthatbetween2000and2007,survivingsmelt occupiedanarrowerrangeofsalinities,andwererestrictedtomoresalinewaters.This indicatesthatlongfinsmelthabitathasbeendramaticallyreduced.

LongfinSmeltLife -CycleConceptualModel

Saltwater-Ocean-EstuaryFreshwater

“TurbidityMaximum”

VerticalMigration SalinityStratificatiion ƒ x=flow,tidalenergyanddepth

Figure5.2.JimHobbs’longfinsmeltlife-cycleconceptualmodelindicatesthat larvalfishperformverticalmigrationonatidalcurrentcycletomaintainposition neartheentrapmentzone,anareaofhighproductivityandfoodavailability.

Dr.JoshIsrael(UC-Davis)presentedpreliminaryresearchcomparinggeneticinformation forlongfinsmeltinLakeWashington(Seattle,WA)andtheBay-Delta.Hefoundthat althoughthemajorityofthevariationwaswithinratherthanbetweenthepopulations,it waspossibletomatchanindividualtothecorrectpopulation.Thesefindingssuggestthat thetwopopulationsaregeneticallydistinct.Furtherconfirmationofthesefindingscould helptodeterminethattheSanFranciscoBaypopulationisadistinctpopulation,which mayresultinaFederaldecisiontolistthepopulation.

5.1.2. Impactsofdredging Althoughdredgingcanhavebothdirectandindirecteffectsonlongfinsmelt,studiesto datehavefocusedonentrainmentandotherdirecteffectsonly.Severalparticipants indicatedthatindirecteffects,suchasinvasivespeciesandharmbycommercialvessels, shouldalsobeconsidered(Table5.1).Whereasmostpotentialeffectsweredescribedas negative,increasedturbiditymayhaveapositiveeffectonlongfinsmelt.Specifically,Dr. Hobbsfoundahigherdensityoflongfinsmeltinmoreturbidwaters.Thisfinding suggeststhatlongfinsmeltappeartoseekrefugefrompredatorsinturbidwaters.Dr. Hobbsalsodiscussedthepotentialfornewdredgingprojectstochangehydrodynamics andhabitat.Longfinsmeltmaybeparticularlysensitivetochangesinhydrodynamics,as

19 theyappeartousechanneldepthandthepatternofwaterflowthroughachannelto maintainpositionneartheentrapmentzone(Figure5.2).Substantialchanneldeepening couldconceivablyincreasestratificationandconsequentabilityoflongfinsmeltto maintainpositionbyverticalmigration.

BrianSwedbergandJohnZentner(PortSonoma)andJordanGold(Mari-Gold EnvironmentalConsulting)presentedtwostudiesthatmeasuredtheimpactofdirect entrainmentbyhydraulicdredgingonnativefishes.In2007,Mr.SwedbergandMr. Zentnerfiltered65,000cubicyardsofdredgedmaterialfromthePortSonomaprojectat themouthofthePetalumaRiver.Whilelargenumbersoflongfinsmeltwerecaughtin theareawhentrawlingforshrimp(establishingpresence),nolongfinsmeltwerefoundin thedredgedsedimentin2007.Ninety-ninepercentoffishcaughtwerenon-nativegobies, with15nativefishcaughtintotal.Mr.SwedbergandMr.Zentneremphasizedthe importanceofcorrectdredgingtechnique-onelongfinsmeltwasentrainedin2006while thedredgeheadwasrunningabovethesedimentsurface.Correcttechniquecouldhave preventedentrainmentofthatfish.

Mr.GolddescribeddeepwaterchanneldredgemonitoringworkperformedforRoss IslandSandandGravelCo.(subcontractortoUSACE).Forthisprogram,situatedinthe Delta,heconductedbothfishcommunitysamplinganddredgeentrainmentsampling. Between2006and2009,longfinsmeltwasthemostcommonnativespeciesencountered incommunitysampling.Of32,067individualfishfrom32species,918longfinsmelt werecaught.In2006,895ofthelongfinsmeltcapturescamefromadredgesitenearRio Vista.Sincethen,twolongfinsmeltwerecapturedin2007,21in2008,andzeroin 2009 6.Althoughtheprogramonlysamplesfishatdredgesites,itislikelythatthe elevatedcapturein2006resultedfromarelativelyhighabundanceofyoungofyearfish, resultingfromhighriveroutflow(Figure5.4).Mr.Goldhypothesizedthatthereduced catchbetween2007and2009couldalsoresultfromdecreaseddredginginthelower reachesoftheriversandashortenedworkwindow,comparedto2006(andthereforeless overlapbetweendredgeactivityandsmeltdistribution).

Mr.Goldalsoperformedanentrainmentstudyusingacustom-builtentrainmentscreen. Inthisstudy,725fishof15specieswerecaptured.Themajorityofthecatchwas composedofnon-nativespeciesincludingshimofurigoby,channelcatfish,andwhite .Nolongfinsmeltwerecaptured.IncombinationwiththePortSonomastudy, thesefindingssuggestverylowratesoflongfinsmeltentrainmentduetohydraulic dredging.

6 Bycomparison,twogreensturgeonwerecaptured,bothin2006.

20 Table5.1.Typesofpotentialdredgingeffectsonlongfinsmelt,currentknowledge regardingeffects,andpotentialfuturestudiesthatwillprovidemoreinformationabout theeffects. Effect Currentknowledge Potentialfuturestudies Increased Potentialpreferenceforturbidwaters; Althoughnegativeimpactsofturbidityare turbidity mightprovideprotectionfrompredators, uncertain,smeltpreferenceforturbid butmayimpairfeeding waterssuggeststhatturbiditystudiesmay bearelativelylowpriority Changein Maydisruptorimprovehabitat,particularly Forlargenewdredgingprojectsinprimary hydrodynamics foryoungofyearsmeltthatrelyontidal habitatforyoungofyearsmelt, stratificationtomaintainposition(Figure hydrodynamicmodelingstudiescouldbe 5.2) performedtodetermineeffectsofbottom changeonstratificationandtidalflow Direct Extremelylowdirectentrainmentfrom Additionalstudiesonentrainmentrates, entrainment hydraulicdredging particularlyfordifferentdredgingtypes. Evaluatinguseofclamshelldredgingas mitigationactivityresultinginreduced entrainment Effecton Nothingknownduetorelativedifficultyof Inclusionoflarvalsamplinginentrainment larvae studyinglarvae studies.Modelingstudiestoevaluate potentialforlarvalentrainment Increased Potentialnegativeimpact,asevidencedby Evaluationofmitigationactivitiesto introductionof stepdeclineinabundanceafterintroduction reducespeciesinvasionfromlargevessels invasive of Corbulaamurensis (Figure5.4) species Contaminated Sedimentcontaminationiselevatedinsome Notahighresearchpriorityforthisspecies sediments regionsoftheBay.Somefishspecies(e.g., flatfish,Pacificherring,shinersurfperch, staghornsculpin,andSacramentosplittail) exhibittoxicologicalresponsesat environmentallyrelevantconcentrations. However,longfinsmeltspendlittletimeat thesedimentsurface,likelyresultingin limitedexposuretosedimentcontamination Underwater LittleknownChamberstudiesonbehavioralresponseto noise sonicexposure.Thisincludesthe possibilityofusingsoundexposureasa managementtooltodispersesmeltand reducedirectentrainment Impactsto Introductionofinvasivespeciescouldharm Dietarystudiesonpreybase,including preybase preybase evaluationofuseofintroducedspecies ShipstrikesMultiplefishspeciesinotherregions Specificrisktolongfinsmelt.Study encountershippropellers,sometimes methodscouldincludenetdeployment resultinginmortalinjury.Riskmay behindcommercialvesselpropellers, increasewithhigherpoweredvessels. thoughthesestudiesaredifficultto Substantialcommercialboatingactivity perform (e.g.,cargoshipping)presentsapotential hazardofshipstrikes

21 5.1.3. Otherpotentialthreatstolongfinsmelt TheSanFranciscoBay-Deltalongfinsmeltpopulationsizeisclearlydeclining,andin factiscriticallylow(Rosenfield).Therehasalsobeenarecentdeclineinthenumberof siteswherelongfinsmeltwerefoundduringsampling.Aspopulationnumbersdecline, andperhapsbecauseofthisdecline,thedistributionisalsobecomingrestrictedinrange. Thepanelistsdescribedthreepotentialthreatstothelongfinsmeltpopulation,otherthan dredging:Deltaoutflow,invasivespecies,andchangesintemperature.

Longfinsmeltsurvivalishighlycorrelatedovertimewithwinterriverflowscomingout oftheDelta(Figure5.3).Flowduringtheincubationandlarvalperiodisthemost importantpredictorofthelongfinsmeltpopulationsizeinanygivenyear(Baxter).

100000 B A 10000

1000 B

100 U

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F 60 8 0 2 4 6 8 0 2 4 6 8 0 2 4 17 7 8 8 8 8 8 9 9 9 9 9 0 0 0 9 9 9 9 9 9 9 9 9 9 9 9 9 0 0 0 1 91 1 1 1 1 1 1 1 1 1 1 2 2 2 2 1 9 9 4 Figure5.31.Abundanceoflongfinsmeltpopulationcorrelatespositivelyovertime 9 9 6 withfresh1waterflows(Rosenfield) 9 9 8 2 0 0 0 Anothersig2 nificantimpacttolongfinsmeltmaybetemperature.Thethermaltoleranceof 0 0 2 longfinsm2elthasnotbeenestablished,butseasonalmigrationawayfromhotter, 0 0 shallowerwa4 terinthesummersuggeststhathightemperaturesmaybeastressor (Rosenfield,Baxter).Atwatertemperaturesabove20°C,populationsappeartodecline precipitously(Baxter).ParticipantsdiscussedthepossibilitythatpopulationsinSan FranciscoBayaredecliningbecausewatertemperaturesmaybeslightlytoowarm, especiallygiventhatthisisthesouthernextentoflongfinsmeltrange.Thelackof monitoringofotherlongfinsmeltpopulationspreventsscientistsfrommakinga comparisonacrosspopulations.

Invasivespeciesmayalsobecontributingtothedeclineoflongfinsmelt.RandyBaxter (CDFG)hypothesizedthattheestablishmentoftheinvasiveclam Corbulaamurensis

22 causedastepdeclineintherelationshipbetweenlongfinsmeltsurvivalandfreshwater outflowssothatforagivenflowvolumefewerfishsurvived(Figure5.4).

Increasedoutflow=morelongfinsmelt

6.0 Opencircles=pre-clam FallMidwaterTrawl Filledcircles=post-clam Triangles=POD UpperEstuary– 4.0 2006 2003 2002 2.0 2001 2004 2008 2005 2007 L o

g 0.0

A 3.54.55.5 b

u LogDec-MayOutflow n d a n c e 6.0

LowerEstuary– 2008 2002 4.0 2006 2007 2005 2003 2004 2001 2.0 BayStudyOtterTrawl L o

g 0.0

A 3.54.55.5 b

u LogDec-MayOutflow n d a

Figure5.4.Longfinsmn eltabundanceiscorrelatedwithwinterDeltaoutflow. c Howeversmelthavebe eenlessabundantatagivenoutflow,sincetheinvasionof Corbulaamurensis .Thisisillustratedbythelowertrendline(lightline,grey symbols)sincetheinvasion(Baxter).

5.2. Concernsofstakeholders Apanelofstakeholdersidentifiedconcernsandengagedindiscussionwiththescientists andregulatorsregardingongoingchallengesofmanagingdredgingandlongfinsmelt. ThepanelwascomposedofAnneWhittington(PortofOakland),B.K.Cooper(Western DockEnterprises),J.T.Wick(PortSonoma),JordanGold(Mari-GoldConsulting),and JonRosenfield(TheBayInstitute).Multiplestakeholdersexpressedfrustrationwiththe permittingsystem,currentlackofknowledge,andlackofcertaintyregardingthetrue impactofdredgingonlongfinsmelt.Theydescribeddelaysinpermitapprovalsthatleft themwithanextremelylimitedwindowtodredge.Onedredgingcontractorexpressed concernthatthislimitedwindowforcedhisemployeestoworkextendedhoursto completeallofthenecessarydredging,andcouldposeasafetyhazard.Attemptsto minimizeandmitigatefortakeweredescribed,includingamonitoringprogramthat foundonlyasinglesmeltentrainedinasuctiondredge,butdidnotresultinadredging applicationapproval.Dredgerswouldlikemorespecificguidancefromthestateonhow tomeettherequirementsformitigationandminimization.Otherstakeholdersalso expressedfrustrationatthelackofguidanceonmeetingpermittingrequirements.

Stakeholdersalsoexpressedconcernthatdredgingmightbeunfairlyblamedforthe declineinlongfinsmeltpopulationsdespitealackofevidenceconnectingdredgingtothe

23 declineoflongfinsmelt.Theyemphasizedtheneedtolookatothermoresignificant threats.However,BillBrostoff(USACE)notedthatevenminimalimpactsbecome importantiftheyarenumerousenough.

Inresponsetostakeholderconcerns,JenniferDeLeon(CDFG)emphasizedthatthe stakeholdersdohavealotofcontrolinthepermittingprocessbecausetheycanchoose howtomeetthestandard.Permittingforanewspeciesisanevolvingprocess,andin time,standardconceptsandproceduresforlongfinsmeltwilldevelop.Shesuggestedthat thefuturemaylieinprogram-levelpermitting.Sheadvisedstakeholdersthatitmightbe moreefficienttofirstminimizepotentialimpactstolistedspeciesthroughtheCalifornia EnvironmentalQualityAct(CEQA)process,beforeproceedingwithapplyingforan incidentaltakepermitrequiredundertheCaliforniaEndangeredSpeciesAct(CESA).In someinstances,mitigationmeasuresemployedforCEQAwillreduceoreliminatethe possibilityoftake,andsaveprojectproponentsthetimerequiredtoapplyforan incidentaltakepermitunderCESA.Stakeholdersshouldcontacttheregionalmanager (ScottWilsonfortheBay-Deltaregion,andBeckyOtaforthemarineregion)fordetailed adviceonmeetingtheregulations.

5.3. Futureresearchneeds,andpotentialsolutions Toprotectlongfinsmelt,researchisneededtoidentifythemostsignificantthreats.The researchpresentedsuggestedthatdredgingresultsinverylowlevelsofentrainmentfor longfinsmelt,andthatshrimptrawlinganddecreasedfreshwaterflowsmaybegreater threats.Futurestudiesoneffectsofshrimptrawling,andpossiblemanagement interventionsseemwarranted.Thereisalsoaneedforongoingmonitoringtoestablish currentpopulationlevels,preferredhabitats,andpotentialimpactsfromdredging.Drs. RosenfieldandHobbsemphasizedtheneedtolookatindirectimpactsaswell,including habitatmodificationresultingfromdredging(Table4.1).Dr.Israelsuggestedbuildinga frameworkdescribingthedifferenttypesofimpactsandcorrespondingmonitoring approaches(perhapsmodeledaftertheapproachusedbyDr.Parsleyforgreensturgeon). Stakeholdersandmanagerscouldusethistoidentifytheimportantresearchpriorities.

Dr.Israeldiscussedthepotentialofusingreal-timemonitoringandmanagementtomore accuratelytrackandavoidlongfinsmelt.However,asDr.Rosenfieldpointedout,this mayhavelimitedutilityonaprojectbyprojectlevel.Itmaybemoreusefultouse researchtobuildamorecomprehensivepictureoffishmovementsthroughouttheBay, particularlyinshallowregions.Real-timemonitoringmightbevaluableforalarge-scale project,butotherwisemightnotbethemostcost-effectiveapproachbecauseitwouldnot beapplicableelsewhere(Baxter).Instead,alarge-scaleBay-wideprogrammightbemore effective.

Aswithgreensturgeon,futureappliedresearchshouldfocusondevelopingeffective managementstrategiesforthisspecies.Suggesteddirectionsforfutureresearchtopics includethefollowing;however,prioritizationofthesetopicswasnotaddressed 7: 1.Identifyrequiredspawningmicro-habitat.

7 Theneedforfutureactivitiestoprioritizeamongandcriticallyevaluatethesesuggestionsisdiscussedin Part6.NextSteps.

24 2.ConfirmwhetherlongfinsmeltinSanFranciscoBayconstituteagenetically distinctpopulationfromtheLakeWashingtonpopulation,whichwould provideabasisforfederallisting. 3.Measureentrainmentlevelsfromclamshelldredgingascomparedtoother methodstoestablishwhetherthetypeofdredgingaffectsimpact. 4.Measureandmodelimpactsofchanneldeepeningonverticalstratification andconsequentverticalmigration. 5.Monitorandmodeldistributionoflongfinsmeltinareasthatarenotcurrently dredgedorsampled.Forexample,developasamplingprogramcovering shorelinehabitatacrosstheaxisoftheBayinordertoincreaseunderstanding oflongfinsmeltuseofshallowareas.Useofthishabitatiscurrentlypoorly understood. 6.Developmethodstounderstandandmeasureindirectimpactsofdredgingon longfinsmelt,includinginvasivespeciesandharmbylargevessels,including propellerstrikes. 7.Evaluateimpactsnotrelatedtodredging,suchas: a.Globalwarming b.Changeinsalinitylevelsandfreshwateroutflow c.Shrimptrawlingandothernon-dredgingformsoftake

Inadditiontoresearch,participantsidentifiedtheneedforgreatercollaborationand communicationbetweendredgers,regulators,researchers,andtheCDFG.Anemployee ofUSACEemphasizedtheneedforcommunicationwithsmallerdredgersandharbor masterswhomaynotunderstandtheregulations.Mr.Goldobservedthatmonitoring programsneedtocoordinatewithdredgerstodevelopappropriatemethodstomonitor take.

Tosupportadditionalresearch,stakeholderssuggestedpoolingresourcesanddeveloping amoreintegratedregionalapproachratherthanfocusingoneachpermitindividually. Severalparticipantsindicatedthataprogrammaticrestorationandmonitoringprogramis neededtoimprovethehealthofthespecies.Stakeholdersalsoobservedthatinitial paymentstocoverresearchmayresultinsavingstodredgersoverthecourseofaproject.

25 6. NEXTSTEPS

Thetwosymposiaprovidedasummaryofthegeneralconceptualunderstandingofgreen sturgeonandlongfinsmelt,includingsomeofthelatestresearchfindingsanddiscussion ofpotentialdredgingimpacts.Alistingofpotentialfuturestudieswasalsodevelopedfor bothspecies(Table4.1,Table5.1).Symposiumparticipantsincludedscientists, managers,andstakeholdersinterestedintheongoingmanagementofthesetwospecies.

Thesesymposiaprovidedthefirstopportunityforthepresentingscientiststoconsiderthe potentialimpactsofdredgingactivitiesonlongfinsmelt.Forgreensturgeonaswell, thereseemedtohavebeenlimitedpriorcoordinationbetweenthescientistsandlocal managers.Additionalprioritizationandcoordinationbetweenscientistsandstakeholders arewarrantedindevelopingconceptualmodelsandresearchprogramsforgreensturgeon andlongfinsmelt.

WerecommendthattheLTMShostaworkshoptofollowupontheideasandresearch directionsidentifiedduringthesymposia.Oneofthemajorgoalsofthisworkshopwill betofacilitatediscussionstargetedtowardsspecificLTMSmanagementneeds,rather thanthegeneralresearchfindingsofthepresenters.ThiswillprovideLTMSmanagers theopportunitytoevaluatemanagementscenarioswhileatthesametimeconsidering potentialbenefitsorimplicationsoffutureresearch.Inadditiontoactiveparticipants fromtheLTMSprogram,localscientiststhatpresentedatthesymposiumanddredging operatorsshouldalsoattend.Thisgroupshouldincludeindividualswhoarefamiliarwith thepracticalchallengesofdredgingandmitigationactivities,andarealsocomfortable engagingindetaileddiscussionswithregulatorsandacademicscientists.

Thefollowingthreetopicscouldprovideaframeworkforoutcomesoftheworkshop: 1.Arefinedconceptualmodelthata)identifiesthecircumstances(e.g.,timing)in whichimpactsfromdredgingactivitiesongreensturgeonandlongfinsmeltcould beavoided;andb)identifiestherelativeimportanceofdredgingactivitiesamong otherlimitingfactorsimportanttospeciesrecovery(e.g.,contaminantsfrom stormwater,oceanconditions).Thisshouldincludespecificassessmentofspatial andtemporalvariationofspeciesoccurrenceduringdifferentlifestages,in additiontoassessmentoftypesofdredgingactivity. 2.Criticalevaluationofpotentialmanagementandmitigationactivitiesthatare likelytohavegreatestbenefitforthespecies.Thesemitigationactivitiesmight notevenbedirectlyrelatedtodredging,butcouldstillallowthedredging communitytoworkinpartnershipwithotheragenciestoreducethemajor stressorstorecoveryofthelistedspecies(asidentifiedintheconceptualmodel). 3.Afocusedresearchandmanagementagendaforthespecies,toprioritizeamong thewiderangeofpotentialstudies(e.g.,Tables4.1and5.1),basedonthoselikely tohavegreatestbenefitformanagement.Thisshouldnotjustconsiderresearch studies,butalsointegrationofcurrentresearchfindingsintotoolsthatwouldbe usefulformanagers.Toolsworthyofconsiderationincludepredictiveor

26 descriptivemodelsofspeciesdistribution,andpotentialimpactsofvarious dredgingactivities.Anotherpotentialtoolistheestablishmentofinnovative institutionalarrangementsformitigationimplementationacrossjurisdictional boundaries(modelexamplesincludemunicipalandindustrialpollution preventionprograms,toxichot-spotremediationefforts).

27 7. REFERENCES

Adams,P.B.,C.Grimes,J.E.Hightower,S.T.Lindley,M.L.Moser,andM.J.Parsley. 2007.PopulationstatusofNorthAmericangreensturgeon, Acipensermedirostris . EnvironmentalBiologyofFishes 79 :339-356. Armor,C.,R.Baxter,B.Bennett,R.Breuer,M.Chotkowski,P.Coulston,D.Denton,B. Herbold,W.Kimmerer,K.Larsen,M.Nobriga,K.Rose,T.Sommer,andM. Stacey.2006.InteragencyEcologicalProgramSynthesisof2005Workto EvaluatethePelagicOrganismDecline(POD)intheUpperSanFrancisco Estuary.InteragencyEcologicalProgram. CaliforniaDepartmentofFishandGame.2009.AstatusreviewoftheLongfinSmelt (Spirinchusthaleichthys )inCalifornia.ReporttotheFishandGame Commission. Klimley,A.P.,P.J.Allen,J.A.Israel,andJ.T.Kelly.2007.Thegreensturgeonandits environment:past,present,andfuture. EnvironmentalBiologyofFishes 79 :415- 421. Moyle,P.B.2002.InlandFishesofCalifornia.UniversityofCaliforniaPress,Berkeley. Rosenfield,J.A.,andR.D.Baxter.2007.Populationdynamicsanddistributionpatterns oflongfinsmeltintheSanFranciscoEstuary. Trans.Am.Fish.Soc. 136 :1577- 1592. Wilber,D.H.,andD.G.Clarke.2001.Biologicaleffectsofsuspendedsediments:a reviewofsuspendedsedimentimpactsonfishandshellfishwithrelationto dredgingactivitiesinestuaries. NorthAmericanJournalofFisheriesManagement 21 :855-875.

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