Publication No. 72-e28

THE Dl STR I P)JT CV ~ VA~CL

0: CLA~ V C ~ AS

P 1 ATrI) T(~ ~‘ ‘ ~ I ~ F

B

I I4TROOUCTION

THE STAFFS or THE WEYErnIAEUSER ENVIRONMENTALRESEARCHGROUP

AND THE WEYERHAEUSERPULP MILL AT CoSMoPoLIS CONDUCTEDTHIS STUDY IN

8967, ANO 8968.

THERE ARE MANY PUBLISHED REPORTSDOCUMENTINS GRAYS HARBOR

WATERQUALITY. THERE ARE ALSO A LESSER NUMBERor PUBLISHED FIN-FISH

STUDIES AND WORKSPECIFICALLY ON OYSTERS. LACKING AT THE TIME WE

BEGAN OUR SURVEY WERE STUDIES DOCUMENTINGTHE POPULATIONS OF NATIVE

AND INTRODUCEDCLAMS. THUS, WE FELT THERE WASA NEED FOR SUCH STUDIES.

OUR OBJECTIVES IN THE GRAYS HARBORSTUDIES WERE:

I) TO DETERMINE WHAT CLAMS WEREPRESENT;

2) THEIR GEOGRAPHICDISTRIBUTIONS AND ABUNDANCE; AND

3) THE RELATION BETWEENTHEIR DISTRIBUTIONS AND ABUNDANCESAND PREVAIL-

ING WATERQUALITY AND SUBSTRATECONDITIONS IN THE BAY. WE HAVE ALSO

CONDUCTEDCLAM STUDIES IN WILLAPA BAY (SloTH AND HERRMANN: 8972)

WITH SIMILAR OBJECTIVES.

rOR SEVERAL REASONSTHE WILLAPA RESULTS OFFER A BASELINE FOR COMPARISON

OF RESULTS WITH THOSE REPORTEDFOR GRAYS HARBOR.

GRAYS HARBORAND WILLAPA BAY COLLECTIVELY ARE CALLED THE “TWIN

HARBORS” AREA. WHILE SIMILAR IN SIZE1 90 MI

2 AND 850 M11 RESPECTIVELY,

THERE ARE SOMESIGNIFICANT DIFFERENCES BETWEENTHE TWOBAYS IMPORTANT TO

2.

THEIR SNCLL~ISH FAUNA. GRAYSHARBORHAS A RCLATIVELY ORCATEREXPANSEor

TIDE FLAT (55% vs. AND GREATERAVERAGEFRESH WATER INFLOW (11,400 u’s

vs. 3,500 cra.) Tiicsc flATURCS CONTRIBUTE TO A HgGH rLUSHING RATE. IN

WINTER GRAYS HARBOR’S HIGHER RIVER •uworr, APART FROM INCREASING THE lAY’S

RELATIVELY NIGH FLUSHING1 CAUSES REDUCEDSALINITIES THROUGHMOST OF THE

BAY. IN WINTER SICNITICANT AMOUNTSor SEDIMENTS ARE SUPPLIED TO THE BAY

6 ~AND AMOUNTTO 13.5 x 10 FT. ANNUALLY OR ABOUT .OIi% or THE BAY’S VOLUME

(GLANcY: 1971).

GRAYSHARBORHAS TWO PULP MILLS AS WELL AS SEVERAL PLYWOOD

AND SAWMILLS. PULP MILL EFFLUENT RELEASES ARE RCDUCWIN RECENT YEARS.

AT PRESENT IN SUMMER70 To 80 x 10 POUNDSor BOO/DAY ARE RELEASED

S

COMPAREDTO 250 TO 300 X 10 POUNDSDURING AND SHORTLYBCTORETHIS CLAM

SURVEYWAS CONDUCTED. APART ~ftOM THESE LIQUID ErTLuENTS THERE ARC

PRESENT IN THE TIDEFLATS SAWDUSTPROMPAST SAWMILL OPERATIONS.

THESE FACTORS- WATERQUALITY, SAL INITY~ rLuSHINQ, SUBSTRATE

TYPE AND QUALITY — INrLUENCE THE HABITABILITY or AN AREA FOR CLAMS.

Tiuts PAPER REPORTSTHE RESULTS OF DATA COLLECTCDAT SOME60

STATIONS IN THE BRACKISH AND SALT WATER PORTIONS OF GRAYSKARBOR.

THESE STATIONS ARE FROMWITHIN ABOUT A MILE or FHC DAY MOUTH EASTERLY

TO NEAR COWPOINT IN HOQUBAM, SOME 11i MILES (risumc I).

IN CONDUCTINGOUR SAMPLING WE ATTEMPTEDTO EXAMINE REPRESENTA-

TIVE AREAS THROUGHOUTTHE ENTIRE BAY. SAMPLING WASCONDUCTEDAT TIDAL

ELEVATIONS FROMABOUT —2 FT. To HIGH TIDE ALTHOUGHTHE BAY MARGINS HAD

ONLY LIMITED SAMPLING. OUR PRIORITIES IN THE SAMPLING WERE:

,

I) ESTABLISH THE PRESENCEAND TYPE OR ABSENCEor CLAM FAUNA QUALITATIVELY

:

2) ESTABLISH QUALITATIVELY THE NATURE OF THE TIDEFLAT SUBSTRATE;

3) QUANTITATIVELY SAMPLEFOR CLAMS~ AND

OBTAIN CORE SAMPLESOF THE TIDEFLAT SUBSTRATETO DETERMINE ITS

PARTICLE SIZE AND CHARACTER.

INFORMATION RELATING TO PRIORITIES I) AND 2) WEREOBTAINED AT

ALL STATIONS BUT ONLY AT 22 OF THE STATIONS WAS QUANTITATIVE CLAM SAMPLING

PURSUED. SUBSTRATECORE SAMPLESWEREOBTAINED AT 31 OF THE STATIONS.

QUANTITATIVE CLAM SAMPLING INVOLVED STAKING OUT ONE OR MORE

50 FT. TRANSECTSAT A STATION AND DIGGING OUT RANDOMSQUAREFOOT SAMPLES

ALONG THE TRANSECT. THE SQUAREFOOT SAMPLE LOCATIONS WERESELECTED USING

A TABLE OF RANDOMNUMBERS. USUALLY FOUR OR MORESQUAREFOOT SAMPLESWERE

TAKEN ALONG EACH TRANSECT. SINCE WEDID NOT USE A SCREENTO RECOVERCLAMS~

THE SMALLER CLAMS BELOW I/Il. IN. PROBABLYWERENOT RECOVEREDIN PROPORTION

TO THEIR ABUNDANCE. BECAUSEOUR SAMPLING WAS LIMITED COMPAREDTO THE

EXPANSIVE NATURE (~o MIS) OF THE GRAYS HARBORTIDEFLATS~ THE QUANTITATIVE

SAMPLING DATA CANNOTBE EXTRAPOLATEDTO ESTIMATE THE ABUNDANCEOF INTER-

TIDAL CLAMS THROUGHTHE BAY. ANOTHERFACTOR IS THAT MORE EFFORT WASGIVEN

TO SAMPLING AREAS APPEARING SUITABLE FOR CLAMS. USUALLY THE VERY SOFT~

WATERY-MUDDYAREAS AND UNSTABLE~ STERILE—APPEARING~SANDY AREAS WERE

NOT QUANTITATIVELY SAMPLED.

CLAMS RECOVEREDIN SAMPLING WERE IDENTIFIED TO SPECIES AND

MEASUREDTO THE NEAREST0.1 IN. OR I MM. THE TIDEFLAT SUBSTRATECORE

SAMPLESWERE ANALYZED AT TWO OR MOREDEPTHS FOR MOISTURES ORGANIC CARBONS

if.

KJELDAHL NITROGEN, AND GROSSVOLATILE SOLIDS. MANY OF THE SUBSTkATE

SAMPLESALSO WERESCREENEDFOR PARTICLE SIZE COMPOSITION.

ALTHOUGHSOMEWATER SAMPLESFOR ANALYSIS WERETAKEN DURING

OUR SURVETS~ THE LIMITATIOtS OF USING SUCH “ SAMPLES~ FOR INTER-

PRETING THE SURVEY RESULTS ARE OBVIOUS. ACCORDINGLY, IN ASSESSING THE

POSSIBLE EFFECTSOF WATERQUALITY CONDITIONS ON THE CLAMS~ MUCHOF THE

HYDROGRAPHICDATA PRESENtED HERE WASFROMTHE MORERECENT PUBLISHED

REPORTSOF BEVERAGEAND SWECKER(1969) AND WESTLEY(1967) AS WELL AS

MANY PROCESSEDHYDROGRAPHICREPORTSAND DATA SUMMARIESOF THE WEYER-

HAEUSERCOMPANYAND THE WASHINGTONDEPARTMENTSOF FISHERIES (WF) AND

ECOLOGY(DOE).

DISCUSSION

ENVI RONMENTALCONDITIONS

SALINITY IS ONE OF THE IMPORTANT FACTORS IN TIC BAY WHICH WE

MENTIONEDAS AFFECTING CLAM DISTRIBUTIONS. USUAL SUMMERAND WINTER

SAL INITIES FOUND IN VARIOUS REGIONSOF THE BAY ARE SHOWNIN FIGURE 2.

THESE USUAL VALUES SHOULDNOT BE INTERPRETED AS EXTREMESENCOUNTEREDIN

THESE AREAS~ HOWEVER. THE REGION LINES IN THE FIGURE ARE BASED ON DATA

EXTRACTEDFROMWEYERHAEUSER,WDF, AND DOE HYDROGRAPHICREPORTS. SUMMER

SALINITIES THROUGHMOST OF THE BAY ARE HIGH. FOR EXAMPLES IN THE Joins

RIVER — PT. NEWAREA OF THE MIDDLE BAYS USUAL SUMMERSALINITIES ARE

AROUND25%c. FURTHER EASTWARDIN THE HOQulAM AREA USUAL SAL INITIES ARE

AROUND20%.. IN WINTERS HOWEVER, SALINITIES AROUND20%. OR MOREoo

NOT OCCUR IN THE REGION EAST OF OCOSTA- OHYHUTAREA.

SUtWER AND WINTER LEVELS OF PULP EFFLUENTS AS INDICATED BY THE

P61 TEST IN THE VARIOUS BAY REGIONS ARE SHOWNIN FIGURE 3. AGAIN, THESE

DATA ARE EXTRACTEDFROMWEYERHAEUSER,WDF, AND DOE REPORTS; MAXIMUMOR

MINIMUM SEASONAL VALUES ARE NOT INDICATED. MEASURABLELEVELS OF PSI OCCUR

THROUGHOUT THE BAY AT ALL SEASONS. THE HIGHEST LEVELS OCCUR NEAR THE

MILL OUTFALLS. LEVELS OVER THE MARINE SHELLFISH AREAS ARE HIGHEST IN

WINTER. IN SUMMERTHE EFFLUENT LEVELS ARE REDUCEDBY TWO—THIRDSOR MORE

THROUGHIMPOUNDING OF WASTESAND SECONDARYTREATMENT.

SUBSTRATEQUALITY IS ANOTHERFACTOR AFFECTING THE DEVELOPMENT

OF CLAM POPULATION IN VARIOUS AREAS. HIGHER ORGANIC LEVEL SUBSTRATES IN

GRAYSHARBOROCCURUPBAY AND ALONG THE SOUTHEASTERNPART OF THE BAY.

ORGANIC LEVELS TEND TO DECREASEPROGRESSINGWESTWARDTO THE BAY ENTRANCE.

FIGURE ~i SHOWSTHE CARSONDISTRIBUTION IN THE INTERTIDAL SUBSTRATES

THROUGHTHE BAY. CARBONLEVELS — ABOUT So TO 90% OF THE TOTAL ORGANIC

LEVEL — WEREUSED SINCE THAT WASTHE EXPRESSION USED BY BEAVERAGEAND

SWECKER(1969), THE SOURCE~r MUCHOF THESE DATA. USUAL LEVELS IN THE

UPPER HARBORARE 2% TO 3%; LEVELS IN THE LOWER HARBORARE MOREAROUND

1%.

THE DISTRIBUTION OF INTERTIDAL SEDIMENT TYPES THROUGHTHE BAY

FOUND IN OUR SAMPLINGS IS SHOWNIN FIGURE 5. WE USED THE QUALITA-

TIVE TERMINOLOGY: GRAVEL, SAND1 AND MUD. QUANTITATIVELY IN CLASSIFYING

SUBSTRATESFROMTHE CORE SAMPLES1 HOWEVER1WE USED THE TERMINOLOGYOF

EMERY (1938), DESCRIBING THE MEDIAN GRAIN SIZE1 MGS.

CLAM DKTRIBUTlONS AND DENSITIES

AEHIOUGH WE FOUND NINE CLAM SPECIES IN THE SAMPLING, THE MOST

WIDELY DISTRIBUTED WERE SOFTSHELL TYPES (FIGURE 6), NOTABLY MYA ARENARIA

,

THE LASTERN SOFTSHELL CLAM, AND MACDMANATSUTA, THE BENTNOSE CLAM,

Two OTHER SMALL SOFTSHELL CLAMS~ CRYPrOMYA CALIFORNICA AND MACDMA

INCONSPICUA, WERE LOCALLY ABUNDANT, THESE LATTER TWO MINOR SPECIES ARE

NOT CONSIDECED IN DETAIL IN THIS PAPER, HAROSHELL CLAMS WERE RESTRICTED

TO THE MORE WESTERNPART OF THE BAY AND THERE, ONLY LOCALLY ABUNDANT.

kELUD 0 W RE CLINOCARDIUM NU~L~L THE COCKLE; TRESUS CAPAX, THE HORSE—

NECK CLAM; SAX IDOMUS 01 GANTEUS, THE BUTTER CLAM; PROTOTHACA,~1NEA

THE NATIVE LITTLENECK, AND VENERUPIS JAPONICA, THE MANILA CLAM,

FIGURE ( SHOWS THE AVERAGE DENSITY OF BOTH SOFTSHELL AND HARD—

SHELL TYPE CLAMS AT STATIONS INCREASING IN DISTANCE FROM THE MOUTH OF

THE BAY, THESE DATA FROM OUR QUANTITATIVE SAMPLING INDICATE HAROSHELL

CLAMS OCCUR IN SIGNIFICANT NUNOERS ONLY IN THE LOWER THREE MILES OF THE

BAY,

THE MOST COMMONSOFTSHELL SPECIES, MYA, OCCURRED AT 29 OF THE

STATIONS COMPARED WITH LINODARIUM. THE MOST COMMON0 THE HAROSHELL

CLAMS, WHICH OCCURRED AT ONLY EIGHT STATlONS, MYA RAN 0 ROM NEAR

DAMoN PT, (STATION 45) NEAR THE MOUTH OF THE BAY EASTWARD TO THE

HOQUlAM AREA OF THE NORTH CIIANNEL ( I I, 9) AND TO NEAR NEWSKAHCREEK

(2i) IN THE SOUTH CHANNEL (FIGURE I, 6), AT THE 21 QUANTITATIVELY

SAMPLED STATIONS ~ DENSITY WAS L~( FT~, WITH A MAXIMUM OF 10,/FT2

(TABLE 1). AT BOTH THE UPPER HARBOR AND THE NORTH BAY STATIONS

(6 AND II STATIONS, RESPECTIVELY) MYA DENSITY AVERAGED2,2/FT,2,

WHILE AT THE 4 Soum BAY STATIONS THE AVERAGE DENSITY WAS 0.2/Fr2.

THE AVERAGE SIZE OF THE MYA CLAMS RECOVEREDWAS ABOUT 2A INCHES;

WITH THE CLAMS FROM THE UPPER HARBOR BEING SOMEWHATSMALLER THAN THOSE

FROM THE OUTER BAY,

HE BENTHOSE CLAM, MACOMANATSUTA, OCCURREDAT H STATIONS;

FROM NEAR DAMON PT., (46) AHO GRASS ISLAND (54) NEAR THE MOUTH OF THE

O V EAS ~W. S TO NEAR NEDS POCK (24) IN NORTH BAY AND AT LEA T TO UPPER

WHITCOMB FLATS (sI) IN SOUTH BAY (flGURES i, 6). AT THE 2~ STATIONS

QUANTITATIVELY SAMPLED ITS AVERAGE DENSITY WAS 0.j3/FT2 WITH A MAXIMUM

OF 5!FT2; THE AVERAGE SIZE WAS L6 IN. (TABLE I), ITS EASTWARD RANGE

WAS NOT SO EXTENSIVE AS MYA AND LOW SAL INITIES IN THE UPPER BAY IN

WINTER MAY BE RESTRICTIVE TO MACDMA NATSUTA. ANoTHER MACDMA SPECIES,

N. INCONSPICUA, OCCURSWELL UPBAY,

CRYPToMYA CALIFORNICA WAS ANOTHER SMALL CLAM (AVERAGE SIZE

0.6 IN.) NOV COVERED IN DETAIL IN OUR SURVEYS, IT WAS LOCALLY ABUNDANT

IN SANDY AR AS FROM WHITCOMB FLATS (50) IN THE SOUTH BAY AND DAMON PT.

(45,44) IN NORTH BAY EASTWARD AT LEAST TO MID UPPER BAY (FIGURES I, 6).

THE HAROSHELL CLAMS ARE CONSIDERED AS A GROUP BECAUSE OF THEIR

MORE RESTRICTED ABUNDANCE, OLINOCARDIUM, THE MOST WIDESPREAD CLAM IN

THIS GROUP OCCURSFROM THE BAY MOUTH EASTWARD IN NORTH BAY TO NEAR NEDS

RoCK (25) AND IN THE SOUTH BAY TO JoI~Ns RIVER (4y) (FIGURES I, 6).

OTHER MS IN THIS GROU APPAR NTLY OCCUR NO FURTHER EAST THAN THE

QYHUT CHANNEL AREA (36-.~9) IN NORTH BAY AND THE GRASS ISLAND AREA (p4)

OF SOUTH BAY, THE DENSITY ESTIMATE FOR HAROSHELLS AT QUANTITATIVELY

0.2/FT2SAMPLED STATIONS WITHIN THEIR ESTABLISHED RANGE WAS WITH A

8,

MAXIMUM OF 0,6/FT2 (TABLE I). FOLLOWING COCKLES IN ABUNDANCEWERE

TH MANILA CLAM VENERUPIS AND HORSE CLAM R SUS CAPAX. NATIVE LITTLE—

NECKS, PROTOTHACA, AND BUTTER CLAMS, SAXIDOMUS, WERE UNCOMMON,

CLAM DISTRIBUTIONS ARE ENHANCED OR RESTRICTED BY ENVIRONMENT

CONDITIONS, GENERALLY, CLAM LARVAE ARE MORE SENSITIVE TO WATER QUALITY

AND SUBSTRATE CONDITIONS; THUS, THE PRESENCE OF LETHAL ENVIRONMENTAL

CONDITIONS WHEN CLAM LARVAE ARE PRESENT OFTEN CONTROLS THE DISTRIBUTION

OF ADULT CLAM POPULATIONS, PEDI.JCED SAL W~TIES OF 14k TO 20k (PHIBBS:

1971), VARIOUS CONCENTRATIONSOF DOMESTIC AND INDUSTRIAL EFFLUENTS IN-

CLUDING FAIRLY LOW (6 12 PPM) CONCENTRATIONSOF SULFITE PULP EFFLUENTS

(WoELKE: ET, AL 1970) AND ANALRO~ ~C WATER CONDITIONS (WALNE: 196 ) AR

DELETERIOUS TO CLAM LARVAE, FOR ADULT CLAMS, PERSISTENT VERY LOW SALIN—

ITIES (MYA: < .5% MACOMABALTHICA < 1%~ LASSIG: 1965; VENERUPIS

,

24k; FUIJIYA: 1962; TRESUS ~27k; MCALISTER AND BURT: 1959), MUCH

HIGHER ILFITE PULP EFFLUENT LEVELS U 000 PP4 FOR MYA AND MACOMA’ NTAC:

1968) AND SUBSTRATES HLGH I~ URGANICS %) (ITO AND MA~: 1955) ARE LETHAL.

WITHIN THE GEOGRAPHIC RANGE WHERE A CLAM OCCURS, DENSITY AND

SIZE ARE ALSO AFFECTED BY THESE STRESSES (BUT TO A LESSER EXTENT) AS

WELL AS BY FOOD ABUNDANCEAND EXPLOITATION BY NATURAL PREDATORS AND MAN,

IN GRAYS HARBOR, EXPLOITATION OF CLAM STOCKS BY MAN IS LOW,

LOW SALINITY IS ONE OF THE IMPORTANT FACTORS IN THE GRAYS

HARBOR POTENTIALLY AFFECTING CLAM DISTRIBUTIONS, SUMMARE SALINITIES,

WHEN MOST CLAMS SPAWN (TRESUS CAPA~,,~ A W INTER SPAWNER IS AN EXCEPTION)

PROBABLY ARE SUITABLE FOR SURVIVAL OF MOST CLAM LARVAE EASTWARD AT LEAST

9.

TO THE JOHNS RIVER — Pr. NEWAREA WHEREUSUAL SUMMERSALINITIES ARE

AROUND25%e(flauRE 2). SALINITY CONDITIONS IN WINTER ARE NOT SO FAVOR-

ABLE THROUGHOUTTHE BAY FOR SURVIVAL OF ADULT HARDHSELLCLAMS~ HOWEVER~

AS SUMMERSALINITIES ARE FOR CLAM LARVAE. USUAL WINTER SALINITIES or

AROUND 20%. OR MORE WHICH ARE SUITABLE FOR MOST ADULT HARDSHELLS

DON’T OCCUR IN THE REGION EAST OF THE OCOSTA— OYHuT AREA. IN MANY

WINTERS, HOWEVER, AVERAGE SALINITIES ABOUT TWO-THIRDS THIS LEVEL PERSIST

IN THE NORTHERN HALF OF THIS WESTERN BAY AREA FOR A MONTH OR MORE

(HERRMANr: 1969). IN SUCH WINTERS AREAS FURTHER EAST, PT. NEW FOR

EXAMPLES MAY GO ALMOST FRESH FOR A PROLONGEDPERIODS A SITUATION CER-

TAINLY LETHAL TO MOST CLAMS WITH THE EXCEPTION OF MYA (HERRMANN, UN-

PUBLISHED DATA.).

REGARDINGTHE POTENTIAL EFFECTS OF PULP MILL EFFLUENTS ON CLAMS~

IN SUMMERWHENCLAM LARVAE OF MOST SPECIES OCCUR, USUAL PULP EFFLUENT

LEVELS (AS INDICATED BY THE P81 TEST) ARE FROM5 PPM IN THE WESTERNBAY

TO 50 PPM NEAR THE MILL OUTFAILS (rIBURE ~4.

IN ~V LABORATORYSTUDIES CONDUCTEDBY DR.WOELICE FRESH SULFITE PULP

EFFLUENTS AT THE HIGHER RANGE OF CONCENTRATIONSJUST MENTIONEDWERE

LETHAL TO EARLY-STAGE CLAM LARVAE (WOELKE ET AL: 1970) AND EVEN SULFITE PULP

EFFLUENT LEVELS DOWNTO THE LOWERRANGE WERE DELETERIOUS. MORERECENT

ICE STUDIES SHOWSECONDARYTREATMENTOF EFFLUENTS SIGNICANTLY REDUCED

THE TOXICITY TO CLAM LARVAE (IVoEucc ET AL: 1971)

IN THESE RECENT STUDIES TREATEDM~ WASTESHAVING A CERTAIN

PBI TEST VALUE WERE ONE—THIRDOR LESS AS TOXIC AS UNTREATEDWASTES

WITH THE SAME PBI VALUE. A MAJOR BOO PORTION OF WEYERHAEUSER’S

10.

CoSMOPoLIS MoO PULP MILL EFFLUENTS ~UMMR R CEIVE SECONDARY TR ATM NT

BEFORE RELEASE TO THE BAY.

IN OTHER LONG—TERM STUDIES WITH MODERATE CONCENTRATIONS OF FRESH

PULP EFFLUENTS IN WILLAPA BAY, HAYDU (I ~8) FOUND JUVENILE CLAMS OF MANY

SPECIES ENTERED THE CONTINUOUS—FLOW BIOASSAY SYSTEM AS LARVAE AND COLON—

I ZED THE MUD SUBSTRATES IN FLOW—THROUGH TEST TRAYS, THE SWL PULP EFFLUENT

LEVEL IN TOE EXPERIMENTAL TREATMENT IN THESE LONG—TERM STUDIES WAS 90 PPM.

AS P81,

TIlE DEGREE OF LETHAL ITY OF THE LOW SUMMER PULP EF LUENT LEVELS

TO CLAM LARVAE IN GRAYS HARBOR IS CLOUDED BY THIS DIVERSITY OF RESULTS,

IT IS ESPECIALLY DIFFICULT TO EXTRAPOLATE TOXICITY FROM THE LABORATORY

TO THE FIELD ON THE BASIS OF THE P81 TEST~ THC TOXICITY TO CLAM LARVAE

OF FRESH EFFLUENTS WITH A CERTAIN P8~ WOULD BE GREATER THAN THE SITUATION

IN THE I ED WH R THERE ~S A MIXTUR O~ OLD (DEGRADED) AND NEW EFFLU NT~

WITH THE SAME P81.

IF THERE IS APPRECIABLE TOXICITY OF PULP EFFLUENTS TO CLAM

LARVAE IN GRAYS HARBOR, THE LARVAE OF THE SOFTSHELL TYPES MUST HAVE A

CERTAIN RESISTANCE, ADULT POFULATIONS OF ALL THREE GENERA — MYA, MACDMA

,

CRYPToMYA OCCUR WELL UPBAY INTO AREAS WHERE USUAL SUMMERP81 LEVELS

ARE 50 TO 50 PPM (FIGURE 3). THUS, LARVAE OF THESE FORMS COLONIZING

THESE AREAS ARE EXPOSED TO THESE LEVELS DURING THEIR DEVELOPMENT,

THE HAROSHELL CLAMS WITH THE EXCEPTION OF CLINOCARDIUM OCCUR

IN AREAS WHERE USUAL SUMMERP81 LEVELS ARE 5 TO 10 PPM, CLINoCARDIUM

,

THE COCKLE~ OCCURSFURTHER EASTWARD INTO AREAS WHERE SUMMERP81 LEVELS

ARE IS TO 55 PPM, ADULT COCKLE POPULATIONS IN THESE AREAS SUFFER

I I.

WINTER DIE-OFFS DUE TO PROLONGED REDUCED SAL INITIES, HOWEVER (HERRMANN,

UNPUBLISHED DATA).

WITHIN THE DISTRIBUTIONS LIMITS OR RANGES FOR EACH CLAM SPECIES

SUBSTRATE FACTORS ARE IMPORTANT~ AFFECTING CLAM DENSITY AND RERHA AL.O

SIZE. METAMORPHOSEDLARVAE MAY NOT COLONIZE UNSUITABLE SUBSTRATES. FOR

JUVENILES AND ADULTS~ HIGHER THAN NORMAL MORTALITIES MAY OCCUR WHEN THEY

ARE EXPOSED TO STRESSES ASSOCIATED WITH POOR SUBSTRATE QUAL ITT.

II~ RELATWG CLAM DENSITIES TO SUBSTRATE CHARACTER~ DATA FOR

WILLAPA BAY SURVEYS (SMITH AND HERRNANN: 1972) ARE INCLUDED. BOTH BAYS

SHARE MANY OF THE SAME CLAM SPECIES, WE WOULDASSUME THAT OTHER ENVIRON-

MENTAL CONDITIONS BEING EQUAL ~N BOTH BAYS THAT A GIVEN SPECIES SHOULD

OCCUPY SIMILAR SUBSTRATES.

FIGoRES 8 AND 9 SHOW AVERAGE MYA AND MACOMA DENSITIES AT

STATIONS WITH VARIOUS SUBSTRATE ORGANIC LEVELS, BOTH MYA AND MACDMA

NATSUTA COLONIZED SUBSTRATES ~4ITH A WIDE RANGE OF ORGANIC CONTENTS

(0,4% TO 4.5%) AND MOISTURE ~YTENTS (18% TO >0%). THE ORGANIC LEVELS

AT THE SURFACE WERE USED IN THIS ANALYSIS. MYA AVERAGE DENSITIES IN GRAYS

HARBORWERE GREATER ON SUBSTRATES WITH 0.5% TO 1% ORGANICS. SUCH SUB-

STRATES TEND TO OCCUR IN THE WESTERN BAY (FIGURE 4). IN WILLAPA, THE

HIGHER MYA CLAM DENSITIES OCCURRED ON SUBSTATES WITH 2.0% TO 2.5% ORGANIC

MATTER. BOTH WILLAPA AND GRAYS HARBOR DENSITY INFORMATION FOR MACDMA

NATSUTA INDICATED HIGHEST DENSITIES AT STATIONS WITH 14 TO 1.5% ORGANIC

SUBSTRATES. THIS SPECIES DID NOT OCCUR IN GRAYS HARBoR~s HIGH ORGANIC

LEVEL SUBSTRATES AS IT DID IN WILLAPA BAY. SUCH HIGH ORGANIC SUBSTRATES

IN GRAYS HARBOR OCCUR IN THE EASTERN BAY WHERE THE LOW SAL INITlES MAY NOT

BE TOLERATED BY M. NATSUTA

.

12,

IN BOTH BAYS MACDMA DENSITlES WERE HIGHER AT STATIONS WHERE

SUBSTRATE MOISTURES WERE FROM 30]~ TO >0% THAN AT HIGHER OR LOWER MOISTURE

CONTENTS. (FIGURES 10, II). MID~DEPTIA MOISTURE DATA WERE USED SINCE WE

THOUGHT THESE WERE LEAST AFFECTED BY CONDITIONS OF SAMPLING AND SAMPLE

STORAGE, THERE WAS A HIGHER DENSITY OF MYA CLAMS ON HIGHER MOISTURE SUB~-

STRATES IN ~HE ~4ILLAPA SAMPLES (FIGURE II) BUT IN GRAYS HARBOR DENSlTIES

WERE HIGHER AT STATIONS WHERE MOISTURES WERE LOW R IO~ TO o%. MOISTURE

CONTENT AT STATIONS WHERE THESE TWO SPECIES OCCURRED RANGED FROM 15% TO

58%, INDICATING A NEED FOR A FAIRLY FIRM SUBSTRATE.

GRYPTOMYA THE OTHER CLAN IN THE SOFTSHELL GROUP WAS MORE SPECIFIC

IN ITS SUBSTRATE REQUIREMENTS. AT THE STATIONS WE SAMPLED IT COLONIZED

MOST AFTER SUBSTRATES WITH LOW ORGANIC LEVELS~ ~ 15% TO I. 1%) USUALLY

WITH MOISTURE CONTENTS OF 204~ TO ~o%.

FOR HAROSHELL CLAMS SUBSTRATE SPECIFICITY WE USED THE POOLED

DATA FOR CLINoCARDIUM AND VENERUPIS SINCE BOTH SPECIES TEND TO BE SURFACE

DWELLERS. Too FEW STATIONS WERE SAMPLED IN EITHER BAY WHERE FORMS SUCH

AS SAXIDoMUS AND TRESUS OCCURRED. FIGURE 12 SHOWS AVERAGE CLINoCARDIUM

AND VENERUPIS DENSITIES COMBINED ON VARIOUS ORGANIC LEVEL SUBSTRATES,

GRAYS HARBOR DATA EXCLUDED STATIONS OUTSIDE THE KNOWN RANGE OF CLINo

—

CARl) IUM. TIlE RANGE OF SUBSTRATES COLON I ZED WERE FROM 0.57~ ro I .5%,

AVERAI;E DENSITIES (MAlNEY VENERUPIS CLAMS) ARE MUCH GREATER IN WILLAPA

THAR IN GRAYS HARBOR, A SITUATION NOT OBSERVED FOR THE SOFTSHELL CLAMS,

ONE OBVIOUS DIFFERENCE IN THE SUBSTRATES INHABITED BY MYA AND

MACOMA CLAMS IS PARTICLE SIZE (FIGURES I~, 14). GREATER MYA ARENARIA

DENSITIES OCCURRED AT STATIONS IN BOTH BAYS WHER T MGS (MEDIAN GRAIN

1j5.

SIZE) WAS LARGER’ DENSITIES DECREASED WITH DECREASING HGS, CONVERSELY

FOR NACOMA NATSUTA, CLAM DENSITIES TENDED TO BE GREATER AT STATIONS WHERE

MGSWAS LOW THAN WHERE tAGS WAS HIGH. THE LIMITED tAGS DATA FOR CRYPToMYA

INDICATES A NARROW SIZE PREFERENCE, AROUND 0,2 TO 0,25 MM; SUBSTRATES

WITH LARGER AND SMALLER PARTICLE SIZES ARE UNCOLONIZED. OUR tAGS DATA FOR

HAROSHELLS IS ALSO 00 ITE LIMITED’ FOR TIRE FEW STAT IONS WHERE THESE OCCURRED

WHERE tAGS W~S DETERMINED THERE WAS WIDE RANGE OF PARTICLE SIZER 0,2 MM

TO 0,5 MM. THIS SITUATION IS NOT UNLIKE THAT FOUND FOR NYA

,

IN SUMMARY, NINE CLAM SPECIES WERE FOUND ~N OUR SURVEY OF GRAYS

HARBOR WITH tA~A ARENARIA AND MACOMA NATSUTA BEING THE MOST ABUNDANT AND

WIDESPREAD SPECIES, THE EASTERN DISTRIBUTION LIMITS OF THE TWO SPECIES

ARE THE HOQUIAM AREA AND THE REDS ROCK - JOHNS RIVER AREAS RESPECTIVELY,

THE MORE LIMITED POPULATIONS OF HAROSHELL CLAMS OCCUR ONLY IN THE MORE

WESTERN PORTIONS OF THE BAY. WE FEEL THIS RE~TRICTCO DISTRIBUTION IS A

REFLECTION OF THE EFEECT OF iRE LOW SALINIl ICS ON ADULT POPULATIONS IN

WINTER RATHER THAN OF DELETE <SOS CONDITIONS OF PULP EFFLUENTS TO CLAM

LARVAE IN SUMMER, SUBSTRATES WHERE SOFTSHELL TYPE CLAM POPULATIONS ARE

FOUND WERE CHARACTERIZED BY LOW TO HIGH ORGANIC CONTENTS AND MOISTURE

CONTENTS. NYA AND THE HAROSHELL CLANS AS A GROUP PREFER COARSER SUB-

STRATES, HOWEVER, THAN MACOMA. THE HARDSHELL CLAMS CLINOCARDIUM AND

VENERUPIS AND CRYPToMYA ARE MORE SPECIFIC, COLONlZING LOWER ORGANIC

LEVEL, GENERALLY COARSER SUBSTRATES.

VK K

F. B. HERRMANN

REFERENCES

I. BEVERAGE, 3. P. AND N. N. SWECKER. 1969.UPPER GRAYS HARBOR, WASHINGTON. Gco. SUR.

1813-B. 90 P.

ESTUARINE STUDIES IN

WATER SUPPLY PAPER

2. EMERY, K. 0. 1938. RAPID METHODOF MECHANICAL ANALYSIS OF SANDS.JOUR. SEDIMENT. PETROL. 8: 105—Ill.

~. FUj~YA, N. 2962. EVALUATIoN OF THE EFFECTS ON BIVALVES (TRANS.)

IN PHYSIOLOGICAL STUDIES ON THE EFFECTS OF PULP MILL WASTESANDAQUATIC ORGANISMS. NAIKAI REG. FISH. LAB. BULL. II. 100 P.

4. HAYDU, E. P. 1958. A CONTRIBUTION TO THE DEVELOPMENTOF OYSTER

BIOASSAY METHODOLOGY. WEYERHAEUSERCOMPANY, LONGVIEW, WASH. Illi P.

5. HER~MArn~, R. B.INE ENVIRONMENT

DECEMBER 9968.

1969. A STUDY OF THE PACIFIC OYSTER AND THE ESTUAR—

IN NORTHBAY OF GRAYS HARBOR., FEBRUARY 2963 TO

WEYERHAEUSERCOMPANY, LoNGVIEW, WASHINGTON. 311. P.

6. ITO, S. AND IMAI, T. 1955. ECOLOGYOF OYSTER BED (PART I).ON THE DECLINE IN PRODUCTIVITY DUE TO REPEATED CULTURES.

TOHOKAJOUR. OF AGRI. REs. 5 (4): 252—268.

7. LAssIe, 3. 2965. THE DISTRIBUTION OF MARINE AND BRACKISH WATER

LAMELL. BRANCHESIN THE NORTHERNBALTIC AREA. SOC. SCI. FENNICA

COW4ENTBIOL. (HELSINKI) 28: 1—41.

8. MCALISTER, B. AND W. BURT. 2959. REcENT STUDIES IN THE HYDROGRAPHY

OF OREGONESTUARIES. ORE. FISH CoMM. Rn. BRIEFS. 7: 214—27.

9. PiuBes, F. D. 1971. TEMPERATURE, SALINITY AND CLAM LARVAE.

PROC. NAT. SHELLFISH AnoC. 61 (ABST.).

20. NATIONAL TECHNICAL ADVISORY CoI4ITTEE. 2968. WATERQUALITY

CRITERIA. MARINE AND ESTUARINE ORGANISMS. FWPCA: 234 p~

II. Swum, S., AND R. B. HERRMANN. 1912. CLAM DISTRIBUTIONS ANDABUNDANCESIN WILLAPA BAY AND GRAYS HARBORAS RELATED TO ENVIRON-

MENTAL CONDITIONS. SUMMARYREPORT. WEYERHAEUSERCOMPANY, LONGVIEW,WASHINGToN. Sli ~.

12. WALNE, P. R.PHYSIOLOGY OF

EDS. ACADEMIC

9964. THE CULTUREOF MARINA BIVALVE LARVAE. JftTHE MOLLUSCA. VOL. I, K. N. WILBUR AND C. N. YoNGE,

PRESS. NEWYORK.

23. WESTLEY, R. E. 2967. PHYTOPLANKTONPHOTOSYNTHESISAND ITS RELATIONs

SHIP TO OXYGENIN GRAYS HARBOR, WASHINGTON. WASH. DEPT. FISH 30 ~.

14. WoELKE, K K, T~ SHlNK, AND K SANOORN 1970. DEvELoPMENr OF AN

IN SITU MARINE BIOASSAY WITH CLAMS. ANNUAL REPORT FOR PERIOD OF

OcTOBER V)69 SEPTEMBER 197K WASH, DEPT. FISH 48 ~.

15~ WOELKE,

TREATED

PEPORT

C. L~, I. SHINK AND L~ SANBORN ~97i~ RELATIVE TOXICITY OF

AND DUTREATED MGO PULPING WASTES. SUPPLEMENTEDPROGRESS

WASH. DEPT. FISH P.

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