Special scientific report

SEASONAL VARIATIONS in
TOXICITY of BUTTER CLAMS
from SELECTED ALASKA
BEACHES

I Marine Biological L-;- •■ ,:i

LIBRARY

OCT 2 31950

WOODS HOLE, MASS.

SPECIAL SCIENTIFIC REPORT: FISHERIES No. 53

UNITED STATES DEPARTMENT OF THE INTERIOR
FISH AND WILDLIFE SERVICE

Ibcplanatory Kot©

The serias embodies results of inTestigatioiiB, xiraally of

restrictad seeps, iateaded to aid or dire^st management or
■a.tilisatioa. practicss and as guides for almiaistrative cr
IsgislatiYe action.. It is issued in limited qTsantities for the
offic'la3. use of Jsdjeral, State or cooperating agencies and in
processed form for eeoaomy and to avoid delaj in pablication..

United St-ates Department of the Intarior

Oscar Ip Ciiapman, Secretary

Fisli and Wildlife Serwice

Albert M. Day, Directed

Special Scientific. Sepcr*. =■ Pisheries
No. 53

SEASOUAL YAEIATIONS IN TOXICITY OF BUTTER CLAMS
PSOM SELBGTED ALASKA BEACHES

By J&im S. Chasnibers a^d
Harris W, Magnassoa

* Chemist, Branch of Commercial Fisheries

** Chemist, Branch of Commercial Fisheries, formerly Fishery-
Products Laboratory , Ketchikan, Alaska, now Fishery
Technological Laboratory, Boston, Massachusetts

Washingtoa, D. C,
August 1950

Introduction

The iRV3S3tigai;ion of paralytic sbsllfish poison in the clams of
Sou'Hheastera Alaska condacted hy the Jish&rj Products LahoratoTy,
Zet'Shikan,!,' was diTidsd into threa main projects. The one with which
this t^por'!-. is con^tseraed '.b the geographical and seasonal distrihution of
th(9 taxltL in Vattes' clams, Saridonriis giganta'^is. The other two projects,
the study of toxin reduction "by processing methods and the study of sampling
aaid testing methods, are to he reported in separate papers. Batter clams
aae the most important ■scmmercial cleun resource in Southeastern Alaska,
IHherafcre, the swdies were devoted almost entirely to this species.

InTestigations of an exploratory Qatu:re performed from 19*46 to
19^8 established the presence of toxin in hutter clams from many of the
Southeastern Ala^ska clam prod-^cing "beaches during all seasons,

ProiE May 19^ to September 19^, inclusive, a systematic monthly
saTiPDling of representatiTe areas on certain eommercially exploitable clam-
produsing beaches was carried out. The purposes of the survey were to
determine the monthly fluct'iations in the toxicity of the clams from the
different areas and the variation in tcxicity between the siphon and the
body. InformatioiS. on ^-hese factors is essential for intelligent regu-
r.ation of this fishery and enables the processor to eliminate a major
so-oree of tox5.3. fr:*!!! the canned product.

Collection of Glam Samples

^e laboratory motor vessel Be searcher, usually operated by a
cr?w of three men, was tised in collecting the clam samples. Shucking of
the clams and preparation of the extracts were performed aboard the boat,

A wi.de knowledge of the elam beds in Southeastern Alaska, gained
froas the earlier gensral survey work, made it possible to select 10
s-epresentativs .^iam beaches on which were laid out 22 plots. Nine of the
■jeaches were knows t-5 produce clams of fairlj!" high toxicity; whereas, the
A-emalni-xig gzl? yielded ciams of low toxicity. Preliminary tox5.city tests
o^a man^' individaal clams from a single plot showed that there was con-
siderable ?a,riatiers. in toxicity between clams. Tb.ese tests further showed
that resul'.ts si^ificant wit'hia plus or minus 30 percent could be obtained from
a sajiiple of 25 clams. Therefore, the plots were made large enou^ to
supply at least 18 samples of 25 clams each. To provide a thoroughly repre-
ssiatati?© sample, not oT<^r 3 clams were taken from each hole dog, and the
holes were distributed well over the entire plot. All the study plots were
iatmdatsd at hi^. '^ater and comrpletely exposed only at a minus tide. The
c'sllections were made, weathjer permitting, during one of the minus tide
periods each month.

1/ Jointly operated by vhe Alaska fisheries Experimental Commiasion and

the U. S. Pish and Wildlife Service.

Ezt-racting and Testing Procgdure

lEie clama were opened with a siiacking knife while they were still
alive „ The shucked olaras were washed in fresh water to remove all foreign
par'iicles from the tissues, and then drair;.ed. The entire siphon (neck) was
severed from the Isody, and the siphons and bodies were treated separately.
These were minced using a hand operated mea's chopper. The ground material
was mixed ihoroughly, and to 100 grams of the minced material was added
100 milliliters of 0„I2 N hydrochloric acid (l part concentrated hydrochloric
acid to 99 parts distilled water). This mixture was boiled for 5 minutes
while baing stirred continuously. After cooling, the mixture was brought
to its original volume by the addition of distilled water. A portion of
the final mixture was bottled and stored in the ice box of the vessel until
the boat returned to Zetchikan, At the laboratory the pH of the extract
was determined with a pH meter, and, when necessary, it was adjusted to a
range of pH 4.0 to 4.5 by adding 5 N hydroch].oric acid or 0.1 H sodium
hydroxide. The extract was centrifuged, and the supernatant liquid was
placed in vials and stored at 0° to 3^ 0, until tests were performed.

The extracts were tested on white mice which weighed between 15
aaid 25 grams. The mice, obtained from a supplier in California, were a
mixture of two strains. Thsy were shipped air espress and arrived at the
laboratory in good eonditioao

The extracts were injected intraperitoneally by means of a two
milliliter insulin syringe. The smallest practicable needle (27 gauge)
was used to redu'je leakage from the puncture. The voliane of extract
injected into each ro.ouse was varied according to the wei^t of the mouse,
One^twentieth of a milliliter of the extract - or diluted extract - for each
gram of live weight was used» This procedure was found to be more satis-
factoiy than the injection of a standard amount of extract and the ajjplication
of a correction factor based on the weight of the mouse.

The lethal time was computed, in seconds, from the time that one-
half of the volume of extract had been injected until the mouse took its
final normal, rhythmic breath. This time of death, in almost every case,
was accoarpanied by a complete relaxation of the body, followed by a series
of reflex motions varying in intensity and duration. When necessary, with
the highly toxic materials, the extracts were diluted so that the lethal
time exceeded four minutes.

A table based on the toxicity curve of Sommer and Meyer (1937) was
used to convert the lethal time to toxicity of the injected solution. The
tonicity of the liaw material, expressed as mouse units per 100 grams of raw
materia],, was calcolated by applying the appropriate dilution factors, A
morise unit (MU) has been defined as that amount of injected shellfish poison
that kills a 20 gram mouse in 15 minutes (Sommer, et al., 1948), Since
Sommer and Meyer (1937) constructed their cui've from data obtained from
mussels, a 3im3.1ar cur^e Tas developed from data obtained using butter clam
extracts. A conrparison of the two carves demonstrated that the data

reported for masael extracts cauld te used satisfactorily la the clam
toxicity assay.

At leasi threa mice were aaed to assay each extract. Bxtensive
test8» had prowA iha.t reaultiB based on the use of three mice gav© an
accuracy of better ihaTj. plas er minus iiZ percent. Errors due to variatioas
in the mice, techxdqo© of iajection, and determination of death-times were
reduced hy rejection of IndiTfldiiml assay results differing from the average
by more than one- third.

Loeatioa of KLots

The locations of the teaches and the distribution of the plots
were based on extensive knowledge of the clam beds in Southeastern Alaska,
acquired from the general surrey. Sfine beaches which past experience had
shown would yield highly toxic clamSp at least during some periods of the
year, and one beach which had yielded essentially non-toxic clams, wer®
selected. These beaches were distributed over as wide an area as it was
practical to v3.sit fraqusntly with the laboratory's motor vessel.

It is to be noted that none of the beaches chosen was from so-
called outside waters, sine® preTicus investigation had shown that clams
from those areas were relatively aon-toxie. However, all the beaches
studied were on fairly wide channels which communicate directly with the
ocean. !Ehe plots wer© on ^.laro I'eds near the mouths of bays or passages
which wer© readily affectisd by the iinirrents in the large channels. None
of the plots was located near the head of a bay or inlet, fhroughout the
entire clam research program it was found that clams decreased in toxicity
as the sampling continf^d toward the head of the bays.

From one to three plots were laid out in each of the ten areas
selected for study. The plois war® outlined by four iron stakes bearing
metal tags stamped with the alphabetic designation of the plot. The 22
plots wer© lettered, A throtigh T, beginning with a beach near Ketchikaa
and ending with a location in Frederick Sound. Locations, descriptions
and characteristics of th© st-ady plots are detailed in Table 1,

The ■onfavora'tel© weather during the winter months and the
considerable distance of some of the beaches from Ketchikan made it
impossible to ob'sain a coarplete sequence of data from each plot. This wais
especially tsTi© in regard to the more northerly plots in Chatham Strait,
Fort-gnately, it was possible to obtain fairly complete data from plots
near Ketchikan,

Plot 0 was ©mitted after October because the float at Fanshaw,
which was the oa3.y safe anchorage in foul weather, was destroyed by a
storm.

E/Unpublished data of report in preparation.

Table i. - "psNTir '.cavjon A^e: D£s::Rip~iCN of ~h£ stuov plo's

Terrain SlopeI/ Area 2/

Plot

locatjcn

Ham 'sland
S° II' 541^ N
I3r 23' lO* V»

Sre

WtS" SIDE OF THE NOR'.'HERN TIP OF H.AM GRAVEL

■ SLAND „ (ttCNfi THE NARRCW PASSAGE CON- SAND

NE<r~!NG' CSBCAOE :i^E" WITrt R£V|L:^dlGEDO SHELL

Channel .

Yards
Sharp »0x3

Ham Island
55° n' 45" N
131° 23' 11" W

SOUnflOEST OF PLO" Aj IMMET ;A-e_r NORTH GRAVEL

0|- A PCIN' rORMING THE HAM ISLAND SIDE SAM3

OF THE NARROWEST PART OF THE PASSAGE. SHELL

Sharp jex4

ANNETTE Island
55° II' 4T N
I3|0 23' 2Cy W

A::RCSS ^'HE PASSAGE, NORTHWEST 0^ PLOT B,
MS" WES~ OF ^'fC ROCKY PO«NT FORMINQ THE
AnNE^'I ':S_AN0 SjDE OF "HE NARROWEST
POIlvr «N "H~ PASSAGE,

Gravel

SHELL

Gentle i ix7

Dall Bav On a s.ngle reef, awash at high "ide, in

55° 09' OE" N Dal_ BaVj Gravina 's^-ANO, westward of the

I3l° 43' 55" W NORTH END OF THE LARGE a.AND X" DALL

Bay, Plot was on the sumvi" o:~ a wash

LYiNG N0RT;SEAST 8V SOUTHWEST ON EASTERN
EN3 OF THE REEF.

Gravel

Sand

Shell

Moderate iOx5

E

Dall Bay
^0 ogt ufcT N
I3l° 43' b/"* W

OAVEST SIDE OF SAME REEF AS PLOT Do

SAND

Shell
Boulders

Gentle

8x8

F

Carlton Island
^° 54' S" N
132° 22' 00* W

On a CONSPICUOUS whce beach, on north-
easy SIDE OF TOE ISJ.ANO,

Gravel
Shell

Sharp

M)6

G

Carlton Island
55° 54' 50» N
132° 21' 50" W

Midway between PuO" F apc southeastern
point of the islando

Sand

Shell

Boulders

Moderate

I8xi0

H

Carlton Island

55r 54' 30» N

132 22' 00» W

On a FLATs EXPOSED AT MPNL'S -;CE, BE-
TWEEN Carlton and Onslcw Sri.ands, ano

JoST NORrHEAST OF "HE HIGHEST' POINT ON
THE RIDGE OF ROCKS R;SING FROM THE FLAT.

Gravel
Sand

SHR.L

Boulders

NEAR:>.Y
LEVEL

I5xi4

1

WRANGELL

Narrows
56° 49' 20^ N
132° 56' 4a« W

On MiThOF SSLAInC, -AS" INSIDE NORTHERN
ENTRANCE TO THE NARROWS^ DIRECTi-Y EAST

OF Flashing Red Buov No, 42.

Gravel

Mud

Boulders

Sharp

15x5

J

San Juan

Island

57° 17' 35» N
1340 00' bU* W

At eimtrance to Pybus Bav, 0.8 mile

SOUTHWES-WARO OF PoiNT PYBUS, ADMIRALTY
iSt-AND. AT MINUS TiDE THE VWO ISLANDS
ARE CON^ECT£C BY A GRAVEL BAR A" THEIR
WESTERN ENDS. PLO" _IES BETWEEN ROCICV
OtrCROPPINGS, FORMING A POCKS'", AT
SOUTHWEST END OF NORTHERN ISLAND, ON
TnE EAST OR FREDERICK SOUfC SIDE OF THE
GRAVEL BAR.

Gravel
Sand

Shell

B0Ua)ERS

Over

BEDROCK

Moderate

10x5

K

San Juan

Island

57° i7' 35" N
f34° 00' 55* W

U'tMM' OiM EAST SIDE OF GRAVEL BAR,
IMMEO'.ATELY SOUTH OF A WELL-DEFINED
SANDY AREA,

Gravel
Sand
Shell
bouuders

GENTuE

22x6

L

San Juan

island

57" 17' 37" N
134° 01' 10^ W

On WEST OR UP-BAY SIDE OF QrAvE. BAR,
NEAR WES^ END OF SOUTH IS_AND IN A
POCKE" FORMED BY THE GRAVEL BtH ANO A
SMAl^ SEEF.

Gravel
Sand

Boulders
Over
bedrock

Gentle

12X5

Pt2L.

TABLE I. - ! PEWIT JFICAT! ON WD DF.Si;RiPr|ON CF "WE SrCfJCV PLOTS ( CONTINUED)

LOCAT ! ON

Sme

TERRaTn S^0P£.I,/ AreST*

RoBERvs Island
57" |8' 06" N
isa** 27* 5(y W

On LAWJEsr OF Roberts .slancs which form the GRAvtit.

souw poitr AT Ti-e entrance to Port Houghton, Sand

WHICH MAK?:S OF- "ROM STEPHENS PASSAGE, PLOT SHELL

WAS ON *ES" OR Stephen? ['Assage side of a Small
sp«T coN^ecTl^a eastern end of thjs island to rocks

A WOOOED islet JMMEOlATELy TO THE SOUTH,

GENTLE

YAR03
|QX8

ROBER-rS I3LAM3

57^ tS' 00" N
133° 27 « 3G" W

Tanshaw
57" l3» 00" h
133^ 30« lO" W

On east or up-ba*
FROM Blot m.

S DG C"^ ""HE SPIT ACROSS

On mainlan;; a~ sou-t-WERN em? of Cleveland
Passage p vshkh lies between MAiNL.ANt) and

WH ! rUSf i SL AMD „ PLOT WAS APPROX I MATELY
lOOO YARDS i\!i-:^''1-W£S" 0." FANSHAW POS"' 0FT!:E.
Was DISC0NTI(>iUE& AFTER OCTOBER BECdJLSE OF
WSAFE -ANCHORAGE If^ FOX WHATWEP,

Gravel
Saw

Shell

Gentle

12x7

Gravel

Mud

Boulders

Gentle

20x7

CHAJK BA';'

57'^ 13" SS'* N
134® 33' 40" W

LEDGE 0,5 MSLE FROW NOP".'>< SHORE OF GRAVEL

,ASE Poiiv; ;, Admiralt!' Saw

SLA^Ei, PLOT WAS OM SOt^HEASTT OR LP=BA^' SHELL
SIDE OF THE LEDGEo

On a baR(

Chaik Bay, snsioe Vi

Plot

Moderate

13x5

Chaik Ba?

134'^ 33' 50" W

Hoco Bav"
^■0 2g« 35^ M

134° 32» 55" W

On Cha-^am S^'rait sine of ledge across from
Plot P» betweei*. rockv owreRoppiNGSo

Gravel

Sand

Boulders

On east side of T^e southern end a^ Sa;^' Gravel

5SLANO5 which' is a SMAuX. I slaw QfT' the east SA(\!D

shore of Hood Bav, Admiralt'v Island, and Shell

^ol"'.' i„5 mules southeasir o'f kllliswoo bouloers
)3la)«„ plot was on east end of a y=3hapec

ii/AShu

Gentle

l7xi{

GENTLE

9X7

s

Hooo Bay
57=^ 26'
134^^ 33«

35" N

tO" W

On WES" EM) OR Cha'tham Strait s'oe of the '^'-

SHAPED WASH 5 ON S^XT^€RM END Ot^ SANO 1 SLAP® 5

ACROSS ?^ROM Plot R„

SANTj

Shell

Gentle

13x6

T

Hooo Bax'

57*^ 26'
,340 329

25» H
55" W

On ENC in- SOtiTK ARM OF THE Y-SHaPED WASH.,

BETWEEN Plots R and S on southern po\nt of
Sand l3LA^f>,

Gravel
Sand

Shell

Gentle

8x8

U

SECURITY

Bay

On reef, awash at high tjde. ojs" west of

MUD

Gentle

5xiO

56" 50' 4S»' N
134*- 20' lO" W

SHAL^OWBIGhT ON VCST SIDE OF C;.Err ISLAI®, SHELL

liM Security Bay, ku:'.i sLA^c. Plot was on Over
east end of a depression bisecting t!-c reef, bedrock
Has an c-OuR of wdrogen suvpkide.

Security Bav
56* 51' oOf" N
134° 2J' CS" W

On the east s jde near the southern end of
Harbor fsLANo, which is norhtwest of Cleft

Island, in SEcuRir? Bay,

GRAVEL

Banc
Boulders

GENTLE

8x6

Sharp Slope i
Moderate Slcpe;
Gentle Slope %

fi. drop of II FOCI IN lO FEET,
A DROP OF i FOOT IN 25 FEET,
A drop of I FOOT l^^ 4C' FEET.

gf Area; first figure is distance parallel to water's eosEo

Digcru-ssion of Egperimeatal Besults

The res-alts of the monthly toxicity tests for each plot are
presented in Tahle 2, The data represent the "ioiicity in mouse xmits per
100 grams of siphons or hodies. The graphic interpretation of this
information is shown in Figures 1 to 9. The toxicities of "bodies ajid siphons
from the same sample have been placed in the same figure. Toxicity cTorres
from plots in the same locality have "been combined in one figure.

The plots studied were typical of the clam beds in Southeastern
Alaska in terrain and clam population. However, as was mentioned previously,
nine of the plots were located on beaches of known high toxicity in order
to provide clams containing determinable quantities of toxin •!;hroughout
the year. This was done so that any fluct'jations in toxicity could be
determined from mo::ith to month.

The reactions of the mice which died when injected with the
extracts of clam materials (either bodies or siphons) were identical to the
reactions described for deaths due to the injection of mussel poison. Two
investigators who had worked extensively with mussel poison confirmed this
observation. In post-mortem examinations immediately after death, the
chambers of the heart were noted to beat rhythmically; this so-called heart
block is a characteristic of mussel poisoning.

The seasonal toxicity characteristics of butter clams are very
definitely different from those of mussels, Rytilus calif omi anus , and
Washington clams, Saxidomus nuttallii. of California (Sommer and Meyer 1937)
and of mussels, Rytilus edulis„ and soft shell clams, Mva arenaria„ of New
Brunswick (Medcof, et al,, 19^7). Studies of the California and New
Brunswick species indicate that there are short periods in the summer months
when they become highly toxic. The toxicity increases rapidly and then
diminishes rapidly within a few weeks. During the winter months these
species are normally relatively free of ^oxln. In the present survey,
except for Plot I, which had relatively non-toxic clams throughout the year,
the butter clams from all the beaches showed some degree of toxicity at
every saurpling.

Prom a study of dino flagellates in these waters made dij.ring the
sunmier of 19^9, the report of which has not yet been published,-*^ it is
known that dinoflagellates of the genus (jop3^u1£lx. a member of which is the
causative organism of mussel poison, do abound in the waters along the
Alaskan beaches studied.

The toxicity of the siphons was regularly much greater than that
of the bodies. However, the ratio of toxicities of siphons to bodies is
not constant. The toxicity of the siphons varies greatly from month to
month, while the toxicity of the bodies does not display a similar degree
of change. The ratio of the weight of siphons to bodies depends upon the
care with which the siphons are removed. The data from three laboratory

2J A study of diaoflagellates in the waters of Southeastern Alaska

carried out by Lucile Foster of the George Williams Hooper Foundation
In cooperation with the Fieheiy Products Laboratory,

experiments using 25 clams eacla show that the siphons were Ik, J to l6,4
percent of the total clam meats, Vhe eijhons were cut from the bodl©«
after the manner of commercial ahucking, ia which appioximately j/h of
the siphon is remoTed. In two additional experiments usiag 25 clams each,
the entire siphons were pulled from the bodies. Separated in this manner,
the siphons constituted 18.5 to 19.9 percent of the total clsun meats. In.
a semi-commercial operation in which 290 bushels of clams were shucked raw
hy a rega].ar shucking crew, who were instructed to cut off all the siphoa
carefully, the siphons were 18.5 percent of the total clam meats. The
£?paration of the siphons in the present- survey followed the latter method,

The resu3.ts of the sur&'ey do not show uniformity in the fluctu-
ation of toxicities of the clams. Brsn those from plots in the same
locality do not always display the sasne vrend.

There is no eTident correlation between the degree of toxicity
and the terrain of the "beach, the magaife^■^.de of the tides, tenrperat'ire of
the water, or amount of daylight. However, the data do suggest a recurring
fluctuation in the toxicity during the year.

Goaclugjoas

A l6 month survey of representative clam beds in Southeastern
Alaska verifies the earlier findings that a toxin or toxins, which cause
reactions in mice similar to those produced by toxin frequently present in
mussels (paralytic shellfish poison), is present In the butter clams of
Southeastern ^aska frosa certain areas during every month,

The toxicity of the siphons is usually several times greater than
that of the bodies.

The toxicity of the bodies does not vary greatly from month to
month, while the toxicity of the siphons shows marked fluctuations.

Literature Cited

MEDCOr, J. C; LEIM, A. H, ; NEEULEE, AXPEEM B.; HEBULEH, A. W. H,;
GIBBAED, J,; and KAUBERT, J.

1947. Paralytic shellfish poisoning on the Canadian Atlantic coast.
Ball. Fish, Ees. Bd. Can., 21. PP. ^H, Ottawa, Ontario,
Canada.

SOMMER, H. , and MBIEER, K, F,

1937. Paralytic shellfish poisoning. Arch. Path., 24, pp. 560-598,

Saja Francisco, California.

SOMMER, HEEMAM; HOMIER, ROBERT P.; BIEGEL, BTBON; STAEGER, D. WAEEBIT;
MOLD, JAMBS D. ; WIZHOLM, DOMLD M.; and ZIEALIS, ELIZABETH SHAME SY.

19^. Paralytic shellfish poison. I. occurrence and concentration
by ion exchange, Joor, Amer, Chem, Soc, 22.* PP» 1015-1018.

Table 2, - monthly toxicity survet cf bltter clam samples from plots on
selected sou^heasterm a_aska btaocs

PLOT

rjo.

LOCATION

TOXICiTY,

May" (946

IN MOLSE UNr,-S PER iCO GRAMS_ OF_MeAT_

July

19^

At.Gi« 1948

Sept. i948

Bodies Sjphcns Boo.es Sjdhck's Boc.es Siphons Bogies Siphons

A

B
C
D
E
F
G
H
1

J
K
L
M
N
0
P

R
S

T
U
V

Ham tsLAi>o
Ham Island
Annette Island
Dall Bay
Oa».l Bay'
Carlton Islatc
Carlton island
Carlton Island
Petersburg
P-/BUS Bay
PvBus Bay
Pybus Bay
Roberts Island
Roberts Island
Fanshaw
Chaik Bay
Chaik Bay
Hood Bay
Hood Bay
Hood Bay
Security Bay
Security Bay

1,200
1,500
2,700
2,400
1,700
1,300
1,200
1,200
200
1,900
1,300
540
2lO
3,500
2,700

4,600
2,900
4,900
3,200
2,900
Lost

2,;ioo

2,000
!80
6,200
6,700
2.600
2,100
6,300
7,900

2,400
1,400

i„aoo

2,100

3,200

800

950

660

NEG.

1,100

1,300

620

1. 800

2,600

1,900

760

350

l„lC0

530

370

23,000
13,000
24„000

17,000

13,000

6,400

3.100

2,900

220

9,200

14,000

14,000

17,000

4,700

5,4(X)

13,000

11,000

16,000

6,700

5,000

3,800

790

1,600

2,600

1,600

•,|00

460

830

930

1,400

1,100

900

2,300

1,400

1,800

520

440

630

470

580

620

28,000

18,000

25,000

14,000

11,000

3,600

3,600

4,100

230

21,000

14,000

14,000

17,000

5,700

10,000

22,000

K,000

9,100

7,400

7,000

5,600

9,100

1,300

1,000

630

MEG,

960

1,300

1,200

660

3,200

1,900

940

360

7lO

900

350

'360

5lO

6,200

3,700

3,500

2l0

)2,0C0

10,000

t5,0C0

(3,000

15,000

12,000

17,000

7,200

11,000

4,900

5,000

7,000

13.000

A
B
C
D
C
"F
6
H
I

J
K
L
M
N
0
P

Q

R
S

T
U
V

Table 2„ - monthly toxi

ICITY SURVEY OF BUTTER CLAM SAMPLES i

FROM PLOTS ON

SELECTED Southeastern Alaska beaches -

Continued

Location

BODIES

Toxic iTv„
1948

.IN MOUSE UNITS PER lOO GS,

ftMS OF MEAT

Plot

NOV. 1948

DE.
Bodies

:. 1948
Siphons

Jan,
Bodies

1949 .

No.

S:phons

Bodies Siphons

S 1 PHONS

Ham island
Ham Island
AN^€TTE Island
Dall Bay
Dall Bay
Carlton Island
Carlton Island
Carlton Islaio
Petersburg
Pybus Bay
Pybus Bay
f*«Bws Bay
Roberts Island
ftoBERTS Island
Fanshaw
Chaik Bay
Chaik Bay
Hooo Bay
Hood Bay
Hood Bay
Security Bay
Security Bay

2,500
1,600
2,000

1,100

1,000

780

Neg.

I„l00

2,000

1,300

1,700

3,900

1,600

760

400

1,100

590

860

I.JOO

1,000

5,100
5^700
4,900

6,500
4,300
Lost
220
(9,000
13,000
(7,000
18,000
16,000
13,000
14,000
5,900
9,500
7,900
8,300
13,000
13,000

l»700
3,600

670

970

8=0
NEG,

760

840

930
1,500
1,-00
Omitted

1,400

920

780

2,600

3,400

1,000

1,200

970

12,000
5,800
6,900
(9,000
(2,000
6,600

1,600
550
1,000
2,300
3,(00

4,(00

4,800

5,400
16,000

!,600

1,100

2,lC0

2lO = '- NEG,
((,000 ...
(0,000
11,000
(8,000 ...

8,700 ...

FROM FURTHER SAMPLING AFTER OCTOBER

(9,000
11,000
(8,000
14,000
(2,000

2lO

8lO
400

3,000

6,200

sel

ected South;

-.'STERN Alaska beaches

- CONTINLIED

Locat ion

Toxicirf„

IN MOUSE UN

its per IOO grams Or

meat

Plot

Feb.

L949

MaRo 1949

Apr, I

1949

May

1949

No,

Bodies

Siphons

Bodies

Siphons

Bod.es

S 1 PHONS

Bodies

Siphons

A

Ham islwc

1,500

24,000

2,000

21,000

2,200

22,000

3,000

20,000

B

H.4tt Island

1,000

12,000

1,100

7,900

670

11,000

2,100

;J,CtX)

C

Annedt Island

!,|00

17,000

2,200

|9„000

1,300

|4,CC0

2,400

16,000

0

Oali. Bay

„

2,600

lO,(J00

3,500

13,000

E

DAf.L Bay

„

B

_

.

2,400

11,000

3,800

10,000

F

Carlton IsU(\)D

„

_

eTo

5,500

700

4,800

870

3,000

G

CARLTCV la^VND

_

_

l.lOO

4,400

1,400

4,700

630

4,200

H

Carlton island

-

»

650

3,200

■ Hon

3,900

690

3,700

1

PtTERSBLRS

_

.

NEGo

200

NEG.

200

NEG«

NEG.

J

PVBbS Bav

o

•

1,100

13,000

1,500

16,000

1,800

|6,U00

K

PyoUS Bay

.

_

1,300

8,300

(,600

to,uuu

1,700

9,600

L

PvBus Bay

•

»

1,300

12,000

920

11,000

l,4C0

14,000

M

Roberts island

-

.

1,600

15,000

1,200

14,000

1,400

11,000

N

RoBCR^s Island

-

-

2,600

16,000

3,200

13,000

2,300

9,200

0

Faims-ww

Omitted from further sampling

after 0;

:tober

P

Chaik Bay

_

_

640

10,000

700

11,000

590

8,30C'

Q

Chaix Bay

.

Cl

970

8,100

750

6,40C<

600

6,800

R

Hood Bav

•

o

1,100

11,000

540

3,300

680

9,500

S

Hood Bay

_

c

480

4,20)

760

5,800

660

4,200

T

Hood Bay

.

.

560

4,60C!

750

6,300

840

3,900

L!

SE'X'air.' Bav

c.

a

470

6,500

40*

5,600

240

3,900

V

SEouRtTv Bay

-

-

690

9,300

540

7,900

790

7,600

Tabu 2. - Monthly toxicity survey

of bltter -

CLAM SAMPLES

; from plots on
- Continued

selected Southeastern Alaska beacs^es

LOCAT ! ON

Toxicity.

IN MOUSE UN

l!TS PER lOO

grams 0-

MEAT

Plot

June 1949

July

1949

AUG,

1949

Sept

. 1949

No.

Bodies

Siphons

Bodies .

Siphons

Bodies

Siphons
12,000

Bodies
1,800

SIPHONS

A

Ham JsLAhc

.

.

1,400

|6,0CX)

2,100

13,000

B

Ham i3LA^e

„

o

620

5,600

1,500

7,900

1,500

ll.CXX)

C

Ammet""e Island

«

_

1,500

\l,CCO

2,700

12,000

1,900

(2,000

D

Dall Bay

„

_

o.

.

1,800

6,8CX)

1,900

9,700

E

Dail Bav

«

«

2,800

4,100

3,100

4,100

3,300

8,800

F

Carlton I slaw

2,100

5,500

1,600

7,5CX)

l,4C0

11,000

=

-

G

Carlton Island

1,300

5,400

1,800

LOST

1,400

7,600

-

-

H

Carltcn Island

1,000

3,400

Lost

8,300

l,40C.

13,000

-

=

1

PETtftSBURG

NEGo

NEG.

NEG.

NEG.

=

=

-

"

J

P-VBL'S BA?

1,400

|2,UU0

1,900

9, £00

l,l-X

7,300

=

=

K

Pybus Say

1,700

8,800

1,600

S,-500

IJOO

11,000

-

-

L

Pybus Bw

1,300

15,000

1,200

16,000

1,200

13,000

=

-

U

Roberts Island

1,900

10,000

2, AX)

14,000

1,100

I2,000

-

-

N

Roberts Island

2,000

13,000

2,500

14,000

1,400

9,700

-

-

0

F«*rvSnAw

Omitted from further sampling ArTER i

October

P

Chaik Bay

850

11,000

1,500

16,000

560

11,000

->

-

Q

Chaik Bay

760

7,700

1,200

9,603

750

10,000

-

-

R

Hood Bay

1,100

9,300

1,400

8,000

480

lljUUO

-

-

S

Hoo) Bay

800

6,500

1,100

9,600

580

6,500

o

-

T

Hood Bay

//U

4,800

1,000

8,100

280

5,000

-

m

U

SfeTij«i'.-Y Bay

760

5,200

1,200

10,000

350

6,600

-

-

V

Security bay

BlO

9,100

1,100

7,800

540

7,800

•

*

Figures 1 to 9 show graphically the monthly
variation in toxicity of the bodies and
siphons of buttex' clam samples from plots on
selected Southeastern Alaska beaches «

10

Interior-=-Duplioating Section, Washington, Do C<. 8276.3

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