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I & I N S W W i l d F i s h e r i e s r e s e a r c h P r o g r a m

Bugs

(Ibacus

spp.)exPloi tation status Fully FishedFor secies o bs are marketed in NSW; bt two secies dominate commercial landins and

both these secies are considered to be lly shed. The recreational catch is insinicant.

Bk

Trawlers of NSW catch or o the eiht knownsecies oIbacus, collectively marketed as

Balmain bs. The most commonly caht NSW

secies are the tre eastern Balmain b (Ibacus

peronii) and the smooth b (I. chacei) which

both row in size to 8-9 cm caraace lenth (CL)

and weih between 300 and 400 . The eastern

Balmain b occrs mainly on inshore ronds

(

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mostly as a by-rodct o rawn trawlin; abot

80% o this catch consists o smooth bs.

Balmain bs are also taken as an incidental

catch by other trawl sheries of sothern NSW

and in other states, and small qantities o

bs are caht incidentally in sanner crab

tras. There is no recreational shery or bsin NSW. It shold be noted that an annal

catch o arond 400 t o Moreton Bay bs or

Bay lobsters (Thenus s.) are also landed by

Qeensland trawlers.

Research into NSW bs revealed distinct

diferences in lie histories between the eastern

Balmain and smooth bs. Eastern Balmain bs

may live or more than 15 years whereas smooth

bs have a maximm lie san o abot 7 years.

Taed smooth bs showed a northward

movement attern that was not evident or

taed eastern Balmain bs. Stdies o theirrerodctive bioloy showed that matrin

smooth bs moved northwards to sawn in

waters of Qeensland, whereas eastern Balmain

bs sawned throhot their rane alon

the NSW coast. It aears that smooth b

larvae (hyllosomata) diserse soth on the East

Astralian Crrent and settle as jveniles on the

NSW continental shel.

Size at matrity or eastern Balmain and smooth

bs is arond 5 cm CL. In 1999, a minimm

leal size o 10 cm (caraace width) was

introdced or eastern Balmain and smooth bsbased on their averae size o emale matrity.

Little is known o the bioloy o the other

secies althoh the eak e-bearin eriod

or all NSW bs is winter.

The two lare secies o bs (I. chaceiand

I. peronii) are not diferentiated in catch retrns

bt samlin will be sed to assess the catch

comosition. Collectively, bs are considered

to be lly shed in NSW waters althoh

no detailed stock assessments have been

comleted. In Qeensland, the act that bs

are relatively lon-lived crstaceans, with low

ecndity and relatively low olation densities

has led to concern that they may be vlnerable

to overexloitation.

W i l d F i s h e r i e s r e s e a r c h P r o g r a m

a n

Bs are taken incidentally by rawn and sh

trawlin in ocean waters of NSW.

The two main secies, smooth b, Ibacus

chacei, and eastern Balmain b, I. peronii, are

inshore secies ond mainly in deths lessthan 100m, whereas I. bruceiand I. alticrenatus

are ond on the oter shel and er sloe

(150-400 m).

Smooth and Balmain bs have overlain

distribtions; however smooth bs are a

more northern secies and are abndant in

Qeensland waters.

Landins o these secies contine to be

monitored with lenth-based samlin.

There is a minimm leal lenth o 10 cm

caraace width and a recreational ba limit o20 bs.

c

Recreational Catch o Bugs

The annal recreational harvest o bs in NSW

is likely to be less than one tonne.

Commercial landings (including available historicalrecords) o bugs or NSW rom 1969/70 to 2008/09 or all

fshing methods. Records rom the mid to late 1980s are

incomplete.

Historical Landings o Bugs

0

20

40

60

80

100

120

68/69 73/74 78/79 83/84 88/89 93/94 98/99 03/04 08/09

Financial Year

Landings

(t)

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s t at u s o F F i s h e r i e s r e s o u r c e s i n n s W , 2 0 0 8 / 0 9

The length distribution o eastern Balmain bugs in NSW

commercial landings has remained relatively stable since

the 1990s, and is mainly comprised o bugs between 5

and 9 cm carapace length (CL). The introduction in June1999 o a minimum legal length o 10 cm carapace width

(approximately 5 cm CL) has apparently had little impact

o the size composition o landings o eastern Balmain

bugs.

2 4 6 8 10

0

2

4

6

8

Age (years)

CL(cm)

femalemale

Growth curves o eastern Balmain bug using parameters

rom Stewart and Kennelly (2000). Lengths are presentedas carapace length (CL).

Length Frequency oEastern Balmain Bugs

Growth curves o smooth bug using parameters rom

Stewart and Kennelly (2000). Lengths are presented as

carapace length (CL).

2 4 6 8 10

0

2

4

6

Age (years)

CL(cm)

femalemale

Growth Curves oSmooth BugsGrowth Curves oEastern Balmain Bugs

0.00

0.05

0.10

0.15

1992/931994/95

n = 1798

Proportion

4 5 6 7 8 9 10

0.00

0.05

0.10

0.15

2000/012006/07

n = 5150

Proportion

4 5 6 7 8 9 10

0.00

0.05

0.10

0.15

2007/082008/09

n = 1277

Proportion

4 5 6 7 8 9 10

CL (cm)

The length distribution o smooth bugs in NSW

commercial catches included a high proportion o bugs

less than 5 cm CL prior to the introduction in 1999 othe minimum legal length o 10 cm carapace width

(approximately 5 cm CL). In recent years the length

distribution o smooth bugs landed by NSW commercial

fshers has mainly comprised bugs between 5 and 7 cmCL.

Length Frequency oSmooth Bugs

0.00

0.05

0.1

0

0.15

0.20

0.25

0.30

0.35

2000/012006/07

n = 19 831

Proportion

4 5 6 7 8 9 10

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

2007/082008/09

n = 9889

Proportion

4 5 6 7 8 9 10

CL (cm)

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F rg

Brown, D.E. and L.B. Holthis (1998). The Astralian

secies o the ens Ibacus (Crstacea: Decaoda:

Scyllaridae), with the descrition o a newsecies and addition o new records.Zoologische

Mededelingen (Leiden)72: 113-141.

Haddy, J.A., A.J. Cortney and D.p. Roy (2005).

Asects o the rerodctive bioloy and rowth o

Balmain bs (Ibacus s.) (Scyllaridae).Journal oCrustacean Biology25: 263-273.

W i l d F i s h e r i e s r e s e a r c h P r o g r a m

Catch rates o bugs harvested using Ocean Prawn

Trawling or NSW. Two indicators are provided: (1)median catch rate (lower solid line); and (2) 90th

percentile o the catch rate (upper dashed line). Note that

catch rates are not a robust indicator o abundance in

many cases. Caution should be applied when interpretingthese results.

Comercial landings o bugs by NSW commercial fsheries

rom 1997/98. Fisheries which contribute less than 2.5%o the landings are excluded or clarity and privacy.

Landings by Commercial Fishery o Bugs

Ocean prawn Trawl (primary Secies)

Fish Trawl (primary Secies)

Catch Per Unit Efort Inormation o Bugs Harvested

by Ocean Prawn Trawling in NSW

State o New Soth Wales throh Indstry and Investment NSW 2010. Yo may coy,distribte and otherwise reely deal with this blication or any rose, rovided that yo

attribte Indstry and Investment NSW as the owner.

Disclaimer: The inormation contained in this blication is based on knowlede and nderstandin

at the time o writin (Aril 2010). However, becase o advances in knowlede, sers are

reminded o the need to ensre that inormation on which they rely is to date and to check

crrency o the inormation with the aroriate ofcer o Indstry and Investment NSW or the

sers indeendent adviser.

97/98 99/00 01/02 03/04 05/06 07/08

Financial Year

Landings(t)

0

20

40

60

80

0.0

0.2

0.

4

0.6

0.8

1.0

93/94 98/99 03/04 08/09

Financial Year

RelativeCatchRate

Haddy, J.A., J. Stewart and K.J. graham (2007). Fishery

and bioloy o commercially exloited Astralian

an lobsters (Ibacus s.). The Bioloy and Fisherieso the Slier Lobster. K. L. Lavalli and E. Sanier.

Boca Raton, Florida, CRC press. 17: 359-375.

Jones, D.S. and g.J. Moran (1994). A Field gide to

Crstaceans o Astralian Waters. Sydney, Reedpblications.

Qeensland Fisheries. (2010). Stock stats o

Qeenslands sheries resorces 2009-10.

Qeensland, Deartment o Emloyment, Economic

Develoment and Innovation: 65 .

Stewart, J. (1999). Asects o the bioloy o Balmainand smooth bs Ibacus s. (Decaoda :

Scyllaridae) of eastern Astralia, university o

Sydney. PhD Thesis.

Stewart, J. (2003). Lon-term recatres o taed

Scyllarid lobsters (Ibacus peronii) rom the east coast

o Astralia, Fisheries Research63: 261-264.Stewart, J. and S.J. Kennelly (1997). Fecndity and

e-size o the Balmain B Ibacus peronii(Leach,

1815) (Decaoda, Scyllaridae) of the east coast o

Astralia. Crustaceana70: 191-197.

Stewart, J. and S.J. Kennelly (1998). Contrastinmovements o two exloited Scyllarid lobsters o

the ens Ibacus of the east coast o Astralia.

Fisheries Research36 (2-3): 127-132.

Stewart, J. and S.J. Kennelly (2000). growth o the

scyllarid lobsters Ibacus peroniiand I. chacei. MarineBiology136 (5): 921-930.

Stewart, J., S.J. Kennelly and O. Hoeh-ldber(1995). An otimal stratey or samlin oocytes

in emale balmain bs Ibacus peroniiLeach

(Decaoda, Scyllaridae). Invertebrate Reproduction &

Development28 (1): 7-11.

Stewart, J., S.J. Kennelly and O. Hoeh-gldber

(1997). Size at sexal matrity and the rerodctive

bioloy o two secies o scyllarid lobster rom New

Soth Wales and Victoria, Astralia. Crustaceana70:

344-367.

please visit the CSIRO website,

htt://www.marine.csiro.a/caab/ and search orthe secies code (CAAB) 28 821019, 28 821004, 28

821001 and 28 821010, common name or scienticname to nd rther inormation.

http://www.dpi.nsw.gov.au/research/areas/systems-research/wild-fisheries/outputs/2003/278_long_termhttp://www.dpi.nsw.gov.au/research/areas/systems-research/wild-fisheries/outputs/2003/278_long_termhttp://www.dpi.nsw.gov.au/research/areas/systems-research/wild-fisheries/outputs/2003/278_long_termhttp://www.dpi.nsw.gov.au/research/areas/systems-research/wild-fisheries/outputs/2003/278_long_termhttp://www.dpi.nsw.gov.au/research/areas/systems-research/wild-fisheries/outputs/2003/278_long_termhttp://www.marine.csiro.au/caab/http://www.marine.csiro.au/caab/http://www.dpi.nsw.gov.au/research/areas/systems-research/wild-fisheries/outputs/2003/278_long_termhttp://www.dpi.nsw.gov.au/research/areas/systems-research/wild-fisheries/outputs/2003/278_long_termhttp://www.dpi.nsw.gov.au/research/areas/systems-research/wild-fisheries/outputs/2003/278_long_term