Distribution and Abundance of the Giant Clams Tridacna Gigas and T

Home , Giant clam, Tridacna

Escape Reef) and listed in Table l . This survey was carried out in concert with a survey of of survey a with in concert out was carried survey l . in This Table listed and Reef) Escape

the (coral trout) survey were adopted as "random' as were adopted survey trout) (coral the

from late January to late March 1983 and during two weeks of May 1983 are shown shown are 1983 May of weeks two during and 1983 March late to January late from

and "chosen" sites. Survey sites on the leeward sides of the 57 reefs selected randomly for for randomly selected reefs 57 of the sides leeward the sites on Survey sites. "chosen" and one another, yet many adjacent clams were unresponsive to the presence of gametes in the the in gametes of presence the to unresponsive were clams adjacent yet many another, one

transects across the continental shelf. Two types of sites were examined: "random" sites sites "random" examined: were sites of types Two shelf. continental the across transects

coral trout trout coral

(Fig. l) in the chronological order in which they were examined (except for reef no. 00, 00, no. reef for (except examined were they which in order chronological the in l) (Fig.

water (Braley, 1984). The density of these clams on a given coral reef may depend on on depend may reef coral given a on clams these of density The 1984). (Braley, water

gathered, particularly for the largest species species largest the for particularly gathered,

strategy. strategy.

relatively undisturbed clam populations where basic demographic information can be be can information demographic basic where populations clam undisturbed relatively

percent of of percent

many reefs within the GBR System is necessary to understand their overall reproductive reproductive overall their understand to necessary is System GBR the within reefs many

clam densities are lacking. The Great Barrier Reef (GBR) is the last large area having having area large last the is (GBR) Reef Barrier Great The lacking. are densities clam

gested by Beckvar (1981) and Gwyther and Munro (1981), are not yet known. Seventy Seventy known. yet not are (1981), Munro and Gwyther and (1981) Beckvar by gested

same or adjacent reefs. Knowledge of a broad-scale distribution of clam densities on on densities clam of distribution broad-scale a of Knowledge reefs. adjacent or same

availability of optimum substrata for settlement and a critical density of broodstock on the the on broodstock of density critical a and settlement for substrata optimum of availability

(Roeding). (Roeding).

Ricard, 1978), 1978), Ricard,

1969; Hester and Jones, 1974; Bryan and McConnell, 1976; Pearson, 1977; 1977; Hirschberger, 1976; Pearson, McConnell, 1974; and Bryan and 1969; Jones, Hester

1980). These cover individual coral reefs or lagoons, but broad-scale estimates of giant giant of estimates broad-scale but lagoons, or reefs coral individual cover These 1980).

derasa

Distribution and Abundance of the Giant Clams Clams Giant the of Abundance and Distribution

Fifty-seven reefs (over 817 km of the GBR; between 20°ll'S-l4°27'S) surveyed surveyed 20°ll'S-l4°27'S) between GBR; the of km 817 (over reefs Fifty-seven

The critical densities of giant clams required to assure success in fertilisation, as sug- as fertilisation, in success assure to required clams giant of densities critical The

be be

Previous clam density estimates include: include: estimates density clam Previous

the northernmost and southernmost areas. Distributions of of Distributions areas. southernmost and northernmost the

abundance decreased southwards: it is rare south of 19°S 19°S while of south rare is it southwards: decreased abundance

Abstract-Fifty-seven reefs were surveyed over 817 km of the Great Barrier Reef. Reef. Barrier Great the of km 817 over surveyed were reefs Abstract-Fifty-seven

temperature and seasonal currents, while salinity or turbidity may be factors which limit limit which factors be may turbidity or salinity while currents, seasonal and temperature

Giant Clam Project, Zoology, James Cook University, Townsville, QW 4811 AUSTRALJA AUSTRALJA 4811 QW Townsville, University, Cook James Zoology, Project, Clam Giant

. .

T. gigas gigas T.

(Plectropomus (Plectropomus

T. crocea crocea T.

neighbors which released gametes naturally occurred within 9-m of of 9-m within occurred naturally gametes released which neighbors

T. derasa derasa T.

(Hamner, 1978), 1978), (Hamner,

spp.) by the Great Barrier Reef Marine Park Authority on 7 7 on Authority Park Marine Reef Barrier Great the by spp.)

Materials and Methods Methods and Materials

on the Great Barrier Reef. Reef. Barrier Great the on

R. D. D. R.

Introduction Introduction

BRALEY BRALEY

T. gigas gigas T.

Tridacna gigas gigas Tridacna

'. '.

Tridacna maxima maxima Tridacna

sites for the clam survey. Surveys of all all of Surveys survey. for clam the sites

T. T.

gigas gigas

and and

T. derasa T. derasa

suggest that limiting factors may may factors limiting that suggest

T. derasa derasa T.

Tridacna gigas gigas Tridacna

(Linnaeus) and and (Linnaeus)

was bimodal with peaks in in peaks with bimodal was

(McMichael, 1972; 1972; (McMichael,

(Hardy and Hardy, Hardy, and (Hardy

Tridacna gigas gigas Tridacna

T. derasa derasa T.

and and T. T. 216 Micronesica

Table I. Reefs or Islands (Is.) visited for the survey. Numbers and names are given with an indication of inner (i), middle (m), or outer (o) reef. Mean no. clams/ha listed as (T. gigaslha, T. derasa/ha).

Mean no. clams per ha Reef Reef at random sites Transect No. Reef name position (Tg, Td)

Innisfail Feather m (0.89, 0.0) 2 Peart m (1.3, 0.67) 3 Gilbey 0 (0, 0) 4 Wardle 0 (9.0, 5.5) 5 So. Barnard Is. (0, 0) 6 No. Barnard Is. (4.0, 0)

Cairns 7 Fitzroy Is. (12.0, 0) 8 Green Is. m (5.3, 3.6) 9 Upolu m (14.2, 0.9) 10 High Is. (12.0, 0) II Russell Is. (12.0, 0) 12 Maori m (0, 0) 13 Channel 0 (4.0, 0) 14 Northwest 0 (4.0, 0) 15 Flynn 0 (1.8, 2.7) 16 Milin 0 (0, 0.7) 17 Arlington m (4.0, 0) 18 Michaelmas m (1.8, 0) 19 Hastings m (0, 0)

Port 20 Batt m (8.0, 0) Douglas 21 Low Is. (0, 0) 22 Snapper Is. (0, 0) 23 Opal 0 (1.3, 0) 24 Tongue m (2.0, 0) 25 St. Crispin 0 (0.6, I.I)

Cooktown 26 Hope Is. (12.0, 0) 27 Cowlishaw (18.0, 0) 28 Egret m (52.0, 0) 29 Boulder m (56.0, 0) sites required the use of SCUBA. At 19 reefs, additional sites were "chosen" for their high clam densities. At the "random" sites, several I-ha areas of reef crest and slope (or patch reefs) were surveyed by setting a 150-m rope parallel to the reef front; and a 67-m tape was placed perpendicular to, and bisected by, one end of the 150-m rope to designate the area. At all inshore reefs (<15 km from the coast), and some middle (25-35 km from the coast) and outer (35- 70 km from the coast) continental shelf reefs, five 50-m x 20-m quadrats were placed lengthwise from the reef crest down the slope and surveyed. Since I was the only one of 2 or 3 divers collecting the clam density data I was able to survey the following

empty shells were concentrated rather than scattered amongst living clams. Although such such Although clams. living amongst scattered than rather were concentrated shells empty

underwater. Counts began after the first group of clams was observed. Areas were deter- were Areas observed. was clams of group first the after began Counts underwater. present study. study. present

areas of disturbance were rare, these data were excluded from mortality counts in the the in counts mortality from excluded were data these rare, were disturbance of areas

reefs; for each 50-m 50-m each for reefs;

areas: for each I-ha plot, 0.3-ha was surveyed at mid-shelf reefs and 0.5-ha at outer-shelf outer-shelf at 0.5-ha and reefs mid-shelf at surveyed was 0.3-ha plot, I-ha for each areas:

mined with a measuring tape or estimated by speed of towing over a known distance. distance. known a over towing of speed by estimated or tape measuring a with mined

initially selected by a viewer from the surface, followed by an observer being towed towed being observer an by followed surface, the from viewer a by selected initially

Instances of probable clam poaching were encountered on outer-shelf reefs where where reefs outer-shelf on encountered were poaching clam probable of Instances

Townsville Townsville

Whitsunday Whitsunday

Cooktown Cooktown

Transect Transect

Lizard Lizard

Flattery-

x x

Reef Reef

20-m quadrat, 500 500 quadrat, 20-m

No. No.

57 57

56 56

55 55

49 49 54 54

48 48 53 53

47 47

52 52

46 46

51 51

50 50

44 44

43 43

42 42

41 41

45 45

40 40

38 38

37 37

36 36

35 35

34 34 39 39

33 33

32 32

31 31

30 30

Vol. Vol.

John Brewer Brewer John

Havana Is. Is. Havana

Pandora Pandora

Lodestone Lodestone

Stucco Stucco

Myrmidon Myrmidon

Dip Dip

Hook Is. Is. Hook

Two Is. Is. Two

Plaster Plaster

Carter Carter Hook Hook

Line Line

odr Is Border

Hicks Hicks

Macgillivray Macgillivray

al Is Eagle

Martin Martin

Linnet Linnet

Day Day

Low Low

Forrester Forrester

Lizard Is. Is. Lizard

Williamson Williamson

Ribbon no. 4 4 no. Ribbon

Ribbon no. 6 6 no. Ribbon

Ribbon no. 5 5 no. Ribbon

no. 15043 15043 no.

20. December 1987 1987 December 20.

Reef name name Reef

(continued) (continued)

Table I. I. Table

odd Is Wooded

. .

2 2

was surveyed. The "chosen" sites were were sites "chosen" The surveyed. was

. .

position position

Reef Reef

m m

0 0

m m

0 0

0 0 m m

m m

0 0

Mean no Mean

at at

(36.0, 0) 0) (36.0,

(24

(0.5, (0.5,

(3.3 (4.5, 9.0) 9.0) (4.5,

(4.0, (4.0,

random random

(0.7, (0.7, (2

(1.3, 18.0) 18.0) (1.3,

20 7 (2.0, (6.2, 5.3) 5.3) (6.2,

53 6 (5.3,

07 4 (0.7,

(3.5, 1.2) 1.2) (3.5,

(2.7, 0.9) 0.9) (2.7,

(4.0, 0) 0) (4.0,

(Tg, Td) Td) (Tg,

0 26 (0,

(0, 8.5) 8.5) (0,

(0, 0) 0) (0,

(0, (0,

(0, 2.0) 2.0) (0, (0, 0) 0) (0,

(0, 0) 0) (0,

(0, (0,

(0, 0) 0) (0,

(0, (0,

. .

, 2 0,

clams per ha ha per clams

, ,

0) 0)

8.7) 8.7)

0) 0)

8.0) 8.0)

1.3) 1.3)

0) 0)

5) 5)

0) 0)

7) 7)

sites sites

0) 0)

7) 7) 217 217

' '

"\ "\

"-.. "-..

\. \.

:u49 :u49

,~B ,~B

" "

' '

---

' '

('.~

HJ HJ

2qo 2qo

50 50

l l

REEF REEF

zi..·· zi..··

~5 ~5

u, u,

1 1

. .

•• ••

contour-

~o ~o

1 1

RS RS

to to

12~ 12~

TE TE

bathymetric bathymetric

10.0 10.0

LOME LOME

' '

\ \

N N

t t

\ \

KI KI

1;; 1;;

100m 100m

'\ '\

I I

-.-52' -.-52'

CENTRAL CENTRAL

50 50

. .

NORTH-CENTRAL NORTH-CENTRAL

,zsl ,zsl

GREAT GREAT BARRIER

Qld

sampling sampling along sites central the north-central to GBR.

\. \.

2:; 2:;

\ \

'\ '\

55 55

' '

_,.,54 _,.,54

9 9

'\ '\

derasa derasa

\ \

I I

• •

I I

T. T.

\ \

I I

\ \

2;;. 2;;.

\ \

.1•t .1•t

·1•3 ·1•3

and and

13 13

14 14

•

1,, 1,,

112 112

,1:; ,1:;

i,, i,,

~; ~;

\ \

J7, J7,

18\ 18\

:~ :~

\ \

::) ::)

.,15\ .,15\

"'~

I I

.-oo .-oo

G)~3 G)~3

[tZ5 [tZ5

8:,-:

• •

5+ 5+

Tridacna gigas gigas Tridacna

, , ¾ '·<:

,:,;:-.···,,24\ ,:,;:-.···,,24\

•.:----.. •.:----..

. .

Barrier Barrier Reef Marine Park Authority's companion map of the GBR, November 1982.

Numbered Numbered reefs are named in legend of Table I. This figure is modified after the Great

. .

Fig

INGHAM INGHAM

--20°s --20°s

--18° --18° I I

vey (GBRMPA) in late 1984 found a single individual of of individual 1984 a single found late in vey (GBRMPA)

hl ef ot f 19°33 of south reefs shelf

These data exclude obvious mortalities from clam poaching at outer-shelf reefs no. 4 and and 4 no. reefs at outer-shelf poaching clam from mortalities obvious exclude data These derasa derasa

Tridacna gigas gigas Tridacna

31. The mean percentages of dead clams from the observed populations of of populations observed the from clams dead of percentages mean The 31.

p<0

cantly more abundant at Escape Reef than either combined "chosen" sites sites "chosen" combined either than Reef Escape at abundant more cantly

the Flattery-Lizard transect on an island reef reef island an on transect Flattery-Lizard the sities sities

borderline as a mid-shelf reef. Although there was no significant difference between den- between difference significant no was there Although reef. mid-shelf a as borderline

dom" sites sites dom"

reef (no. 00, Fig. 3) densities of of densities 3) Fig. 00, (no. reef and and

sites the highest densities of of densities highest the sites

High densities at "random" sites occurred in the Cairns and Cooktown transects. At At transects. Cooktown and Cairns the in occurred sites "random" at densities High reef sites. sites. reef

"chosen" "chosen"

see Figure 3. 3. Figure see

southernmost southernmost

sites (9 reefs) reefs) (9 sites Random Random

Chosen Chosen

(12 reefs) reefs) (12

2 southern transects transects southern 2 Random Random

(45 reefs) reefs) (45

5 5

5. 5.

4. 4.

2. 2. 3. No living living No 3.

01) 01)

Figures Figures

I. I.

of of

Table 2 Table

northern transects transects northern

were 10.4% and 12.7%, respectively. respectively. 12.7%, and 10.4% were

There were 47 dead dead 47 were There

T. derasa T. derasa

Four hundred and six live live six and hundred Four Tridacna derasa derasa Tridacna

Tridacna gigas gigas Tridacna

or combined "random" "random" combined or

sites high densities were found found were densities high sites

. .

1 1

Mean and standard deviation of clam densities at 57 57 at densities clam of deviation standard and Mean

and 2 show clam densities at "random" sites at 57 reefs: for "chosen" sites sites "chosen" for reefs: at 57 sites "random" at densities clam 2 show and

,=9.998, ,=9.998,

is rare south of 19°S, but although no live live no although but 19°S, of south rare is

at "chosen" and "random" sites sites "random" and "chosen" at

transects. The only inshore reef on which which on reef inshore only The transects.

T. gigas gigas T.

was present on on (of 57) 36 was present

Number of clams per hectare hectare per clams of Number

was present at 25 "random" and 9 9 and "random" at 25 present was

S, one long-dead long-dead one S,

were found in the Whitsunday transect, south of 19°S 19°S latitude. of south transect, Whitsunday the in found were

0.001)

T. derasa derasa T.

T. gigas gigas T.

236.6 236.6

7.8 7.8

sites sites

T. gigas gigas T.

6 6

T. gigas gigas T.

. .

Vol. 20 Vol.

. .

± ±

gigas gigas

Discussion Discussion

196

1.4 1.4

and 38 dead dead 38 and

occurred on outer-shelf reefs in the northernmost northernmost the in reefs outer-shelf on occurred

Results Results

6 6

. .

7 7

,=9

in in

December 1987 1987 December

eesgiiatyhge (3/a ta "ran- than (134/ha) higher significantly were

and 261 live live 261 and

T. gigas gigas T.

all five northern transects (Table 2). Escape Escape 2). (Table transects northern five all

(Two (Two

907, 907,

± ±

"random" "random"

(tm,=0.952 (tm,=0.952

p<0.001). p<0.001).

was found. A second coral trout sur- trout coral second A found. was

d. are shown. shown. are d.

ls., no. 45) that may be considered considered be may that 45) no. ls.,

T. derasa derasa T.

5.5 5.5

5.9 5.9

T. derasa derasa T.

9 9

T. gigas gigas T.

random random

T. derasa derasa T.

± ±

7.4 7.4

7.3 7.3

"chosen" "chosen"

sites and 17 (of 19) 19) 17 (of and sites

T. derasa derasa T.

. .

3 3

gigas gigas

ns), ns),

sites and 9 9 and sites

from the 57-reef survey. survey. 57-reef the from

at Hook ls. (reef no (reef ls. Hook at

were noted. noted. were

T. derasa derasa T.

were found at outer- at found were

sites. At "random" "random" At sites.

was present was in in was present was

239.4 239.4

chosen chosen

T. derasa derasa T.

T. gigas T. gigas

6.5 6.5

. .

7 7

Cton=4.249, Cton=4.249,

gigas gigas

± ±

was signifi- was

sites. sites.

7.8 7.8

"chosen" "chosen"

184 184

+ +

6 6

and and

. .

51) 51)

219 219 T. T.

ha ha

shells shells

25 25 ha

. .

ha ha

5 5

empty empty

sampled: sampled:

Poachers) Poachers)

0 0 5-0

( (

1.00 1.00

0.25-1.00 0.25-1.00

Reefs Reefs are displayed

> >

~o.o ~o.o

. .

(no. (no. clams/ha) at 57

Area Area

+Many +Many

• •

o o

derasa derasa

T. T.

,;• ,;•

. .

.. ..

< <

,0.> ,0.>

and and

(no. (no. clams/ha) "chosen" ( reefs at 19

'o.°' 'o.°'

SITES SITES

and and inshore portions cross-shelf the of

, ,

-<.. -<..

derasa derasa

00, 00, Escape Reef, is included comparison for

. .

T. T.

mid-shelf

dacna dacna gigas

. .

, ,

and and

0 0

., .,

RANDOM RANDOM

Tridacna Tridacna gigas

0 0

., .,

0 0 €

z z

0 0

u u

...J ...J

< <

l: l:

II) II)

D.. D..

ILi ILi

D: D:

:c :c

ILi ILi

u u

< <

I-

D: D:

ILi ILi

Abundance Abundance of the giant clams

Abundance of the the of Abundance

. .

with with other reefs. Numbered reefs are named Table in I

sites) sites) on the GBR (refer to Fig 2). Reef no

transects transects (see also Fig. I and Table I)

reefs ( "random" "random" reefs ( sites) on the 'S GBR between and 20°11 14°27'E

from north to south and for for and outer-shelf from to north south

. .

Fig Fig

6' 6'

., .,

~o ~o

() ()

0~ 0~

z z

ci ci

l: l:

Ill Ill

..J ..J a:: a:: < <

u u

Q. Q.

I-

J: J:

a:: a::

w w

LLI LLI

u u

w w

< <

a:: a::

,._: ,._:

a, a,

'°'q, '°'q,

.,o .,o

#;o #;o

~o ~o

1)1 1)1

'V. 'V.

0 0

.._o .._o

CHOSEN CHOSEN

!P"' !P"'

., .,

€ 0

~o ~o

0 0

,._,,.,, ,._,,.,,

t t

SI TES TES SI

o"' o"'

/1, /1,

.r~ .r~

0-i) 0-i)

b,(, b,(,

......

o o • •

< <

?;,•, ?;,•,

.-~ .-~

.. ..

Area Area

.,, .,,

-i) -i)

> >

.. ..

0.05 0.05

o.o o.o

0.25 0.25

1.00 1.00

.r .r

5-0.25 5-0.25

sampled: sampled:

ha ha

1.00 1.00

':, ':,

ha ha ha ha

et et al.,

Ayling, Ayling,

. .

outer-shelf outer-shelf reef

in in situ on the north-

indicate indicate a steady

5 5

T. T. derasa.

gigas gigas

derasa derasa

. .

occurs occurs in spring to mid-

T. T.

30. 30.

227. 227.

Tridacna Tridacna gigas, Tridacna derasa

and and

24:21

3: 221 3:

per per hectare at

T. T. gigas

individuals individuals on the extreme outer reefs of

. .

1987) 1987) these current patterns and larval

Tridacna Tridacna gigas

. .

Aquaculture Aquaculture

T. T. gigas

, ,

. .

is is common at 19°S and as far south as the

T. gigas gigas T.

Micronesica Micronesica

References References Cited

T. T. derasa

Larger Larger numbers of dead clams were found in the north-

at higher higher at latitudes ultimately be may temperature, to due

A A biological survey of selected reefs in the central section of the Great

. .

submitted submitted lo GBRMPA by Sea Research. 53 pp.

ACKNOWLEDGMENTS ACKNOWLEDGMENTS

. .

spawning spawning and growth of the giant clams

, ,

while while salinity and/or turbidity may limit

Repl

. .

1977), 1977), though it was not found in surveys in the Capricorn

Braley, Braley, PhD Thesis

in in Palau, Caroline Islands

T. gigas gigas T.

is common common is on inshore reefs potentially affected by seasonal fluc-

; ;

, ,

University University of New South Wales

22°S), 22°S), the where Coral Sea water mass predominant is (A

L. L. 1985

, ,

. . is restricted oceanic restricted primarily environments to is Heslinga, and (Munro

Reproduction Reproduction in the giant clams

out of of out

T. T. gigas

. .

T. T. gigas

Reproduction Reproduction and Recruitment Giant of Clams and Some Aspects of their Larval Juvenile and

. .

Ayling, Ayling, A

., .,

Tridacna Tridacna squamosa

. .

comm., comm., 1986). Conversely,

Biology. Biology. PhD Thesis

central central Great Barrier Reef and Papua New Guinea. Coral Reefs

and and

Barrier Barrier Reef Marine Park

I thank the Great Great thank I the Barrier Marine Reef Park Authority for making possible this survey

A A GBRMPA coral trout survey of the Far-North section (Lizard Is.-Torres Strait)

Currents Currents in the GBR lagoon at 19°S, 147°50'E (near Townsville) set from west to

Population Population densities of these species are higher further north (from Cairns to Lizard

Tridacna Tridacna derasa

. .

1977). At At 1977). 16°23'S, 145°34'E (near Batt Reef and Low Isles) the current north flows from

Braley, Braley, R. D. 1984

Beckvar, Beckvar, N. 1981. Cultivation

Ayling, Ayling, A

School School of Zoology, University of New South Wales for use of equipment.

--. --. 1987.

1983), whereas whereas 1983),

increase increase from my southernmost transects toward the Far Northern areas (Ayling and

use of equipment equipment of use travel and to reef Escape aboard his research vessel Torito, El to and the in in 1984 also recorded numbers of live/dead

transects. transects. Densities of combined live/dead varied from 14-24/ha, while densities of live

of giant clams in conjunction conjunction clams giant coral of in trout the with survey. thank also I Starck Dr. for Walter 1985). They They also scattered found several 1985).

seasonal seasonal spawning and southerly drift of the larvae.

Ayling, Ayling, 1985)

ernmost ernmost areas presumably due to poaching. These densities for

February-October February-October and south (but less intensely) from October-February (Orr, 1933;

only only /ha clams varied from 0-17

north north from January June to and from south to east from July to December (Pickard

but but the minor recruitment in the southern part of the GBR may have resulted from the

Cresswell Cresswell and Greig, 1978). Since gamete release in

survival survival of young

The The apparent fade

drift drift could be accounting a factor the observed for distribution of this species GBR. the on Is.)

summer summer (Braley, 1984

Bunker Bunker group (A. Ayling, pers. comm., 1986)

tuations tuations in salinity and turbidity. These distributions suggest that temperature may limit

Swains Swains Reefs (Pearson

pers

the Swains group group Swains the (2l

222 222 and and another at a small outer-shelf reef in the Whitsunday transect (Ayling and Ayling,

Ricard, G Ricard,

Orr, A. P. P. A. Orr, Pickard, G. G. Pickard,

etr F Hester, ero, R Pearson,

cihe, D McMichael,

Hamner, Hamner,

rswl, G Cresswell, Hardy ishegr W Hirschberger,

Gwyther, J., Munro, Munro, J., Gwyther,

Bryan, Bryan,

Great Barrier Reef and Western Coral Sea. Austr. Gov't Pub!. Serv Pub!. Gov't Austr. Sea. Coral Western and Reef Barrier Great

ceedings of the Third International Coral Reef Symposium. pp pp Symposium. Reef Coral International Third the of ceedings

dacna maxima maxima dacna

dacnidae). Aquaculture Aquaculture dacnidae).

, , Br. Mus Br.

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