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range. I t has been est imated that some
und.ersize have been brought aboard the
lobster boats each season, and of those
on board for ten minutes or more, wi th
water in excess of two hours (Brown and
16 to 20 m i l l i on
765 professj-onal rock
r e t a i n e d , 2 4 t r e m a i n e d
some being kept out of
Capu t i f 983 ) .
Even though the undersize are returned to the sea as required
by the regulat ions, i t has been shown that not al t of then
survive (Brown and Caput i 1983, Brown et aI . in press). The
reason is that damage suffered by many of them from conf l ict in
the pot and from handl ing on board the boat (exposure, damage
and displacement) $ay prove fatal . The effects of capture and
handl j -ng aLso render them vulnerabl-e to predat ion dur ing the
fal l back to the sea fJ.oor, owing to disor ientat ion caused by
the experience.
B rown and Capu t i ( 1983 and 1985) and B rown e t a l . ( i n p ress )
examined the retent ion and release experience (handl ing) to
ascertain the ef fects of damage, exposure and displacement,
separately and in combinat ion, on survival of undersize. They
then est imated the economic consequences of the mortal j - ty of
undersize dj . rect ly or indirect ly caused by those effects. I t
was found that al l of these factors, damage, exposure and
displacement, resul ted in an est imated reduct ion in recapture
ra te o f 14 .68 i n t he 1978-79 f i sh ing season . A f te r t ak ing i n to
account naturaf mortal i ty, the total loss to the rock lobster
industry due to poor handl ing methods was $9.1 mi l l ion (Brown
e t a I i n p ress ) . B rown e t a l . { i n p ress ) examined the way
f j -shermen emptied rock lobsters f rom the two di f ferent types of
pot used in the f ishery:
L
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ueaAleq ecue.ra;JTp luel.rodurT lsoru eqJ, '1da{ a.raA s.ralsqoT
{cor azTs ar{1 pue ees eq1 01 peuxnler ,{1e1e1peurur1 e:eat
ezTs.rapun 'ezTsfepun ro ezTs a:an rleql .:eqleqA auTu.relap
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pelrasqo sauTlewos sea 1I 'Ja1ea el{l oluT >1ceq 1q6te:1s uno.rql
erar't srelsqoT :{cor azTs.repun If snoTlqo eq? xeql sea 'edIl
1od aq1 :aleler{r'r 'pueq Iq slod 6u1z(1due Jo a.rnlea; 1uel:odur1 ug
'slod aATqaeq a{T T
Icau eq1 q6noJq? pueq ,{q patldua a.reat slod uallPq auos 'rxoQ
pcJecr e oluT 'pua uado eq1 q6no:r{1 1no stalsqol aq1 6u1,{1dura
pue dn +od ar{1 6urddTl '1od eql Io pue eq1 1e (o1E6) xoop
eq1 6uluedo r(q pelldua .[11ensn e:an slod lEIs .ro uo1leg 'q
's1od .rTaql ]o seseq Teels oq+ oluT lTTnq
s:oop 1no-6uT!as peq oqi^,\ ueu:er{sT; eJola Poqlou sTql 01 uolldecxe
ere.r aqJ, 'TTE1 .ro acede:ec 'eeuuelue oq1 oluo 6u1p1oq ,{q
1od eql Jo {cau aql q6no,rq1 lno srelsqol pe11nd uau.ral{sTJ eqfr,
'pueq Iq (rpeuuT{s.,) pelldura eJear slod >tcTls ro alrllaeg
a Sort ing af ter each pot (sequence 2l - Rock Lobsters were
transferred from the pot into a 'cacca boxr and then
sorted direct ly f rom the 'cacca box,. Al I the anj .mals
from one pot were sorted before the next pot was pulled
(and hence nore lobsters were added to. the box) .
Cont inuous sort ing (seguence 3) - Rock lobsters
sorted from the 'cacca box' whenever there vras
avai lable, usuat ly whi le pots were rebaited and
were
time
4 .
when steaming betsreen pots and when winching the
aboard.
s tacked ,
next pot
Errat ic Sort ing (sequence 4) - Sort ing occurred. when the
rcacca boxr was fulJ- , or when a need to determine the
catch rate arose. The contents of the rcacca boxr were
completely sorted af ter a l ine of pots ( i .e. a number of
pots in a part icular locat ion) had been puI led, even i f
t he t cacca box r was no t f u l l .
End of l ine sort ing (sequence 5) - Rock lobsters were
sorted from the 'cacca box' af ter pul l ing a l ine of pots
(Brown et aI . in press). In some cases the obviously
undersize were sorted. direct ly f rom the pot.
Sort ing af ter pulJ. ing and relaying a l ine of pots
(sequence 6) - Pots were emptied into the rcacca boxr and
sort ing took place only af ter a l ine of pots had been
pul led, rebai ted and reset. This procedure usual ly
involved moving the line of pots some distance before
resett ing them.
6 .
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aq1 ,uoTlTppe uI 'sTesseA :olTuolu pue alecoT o1 pe:1nba:
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luecTJTu6Ts p Jo uoTlelresqo eTqerTer pelelTTlceg: I:aqs1g
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'uaTqolct oq?
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I11uec1g:1u6Ts 01 spoqleu 6u11pueq ,rTer{l e6ueqc 01 uaql JoJ
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ruroJuT o1 auue:6o.rd uoTlpcnpa qluou gf aATsueluT ue palerlTuT
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,pecnpo: IT1ee.r6 oq pTnoc s:olceJ aseqf Jo lcaJ:]e eql 'spoqleu
6ur1:os rror{l paTl:Tpou ueu.reqsTtr IT 1el{l penor{s slTnse.: eqtr
I I METHODS
The rock lobster f ishing f leet was monitored dur ing the 1983-84
rock lobster season. A sample was taken of one hundred and
f i f teen boats (158 of the f leet) at seventeen anchorages along
the coast (Figure I and Table 1,) . Fishermen working gear in
depths of 36 m (20 fms) or less, were approached to take
research staf f on board. The depth constraint was adopted
because the greatest numbers of undersize rock lobsters are
caught within this depth category (Brown and Caput i l -983).
On board the f ishing boats, the t ime when each rock lobster pot
was brought aboard ( i .e. start t ime) and the pot type rr /as
recorded, and an est imate of the number of rock lobsters in the
pot was made. The rock lobsters were taken from the pot and
either thrown overboard i f undersize or carrying spahrn, or
placed in the sort ing box ( 'cacca box') f rom which they were
then ei ther returned to the sea (undersize and spawners) or
kept with the catch ( i .e. lobsters with a carapace measurement
greater than or equal to 76 mm). During the sort ing process,
the numbers of undersj-ze, s ize and spawning animals were
counted and a total for the three groups was made when sorting
was completed. When al l the undersize had been returned to the
sea, an end t ime was recorded. When the next pot was pul led,
t in ing started agaj.n. I f a l l the rock lobsters were not sorted
before the next pot was pul Ied, a part ia l sort notat ion was
entered and the t ime recorded. Timing started again when the
next pot came on board.
L
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aq1 6ursn sacuanbas 6u11:os aATI aql Jo qcee ro] ssluTl e:nsodxa
palcedxe paleTncTec euue:6o:d aq6 ' (eTTeflsnv u.relseM '0209
'qceag qlfoN '02 xos 'O'a 'luaux:edeq se1:aqsrd) TTeH 'N Xq
ua11T.rA eurure:6o,rd e 6u1sn passeco:d pue paleTToc af,aA plep aq;,
buTssacoJd elec
'e1ep oql ]o uoTlceTToc aq1 6ut:np
pel.rasqo serr,r leqA uo peseq 'lpoq qcea o1 acuanbes 6u11:os
e paubrsse JJ€1s qc.reasa.r 'dTr1 6ulqsrg: eq1 Jo pua aq1 1V
'pautelqo e.ran uorlerado 6ulqsrg:
aq1 Io s€.rnlEa] raq+o pue uorlepe:d Jo acuepT^e ,sralsqoT
{coJ J:o 6utlpueq 1e:eua6 ,uolllsodrloc Aa.rc ,pasn sXTeq
'1eoq eq1 uo uotllsod sxT pqe uoTlcnJlsuoc rxoq eccecr ,peqsT]
sqldep 'raqlee.rr oq1 uo selou 'leoq 6u1qs13: aql pJeoqe eTrr{M
'(g aTqe,I) (leefJ eql fo eldures uopup.r e 'a'r) s{ooq
6o1 qc:easer uroJJ paATrep uorleuJotur eues aq1 qltrr pa.redruoc
aq ileur (Z alqe,I) slTnse.r eqI 'e^oqe aq1 Jo suoTlrurquoc
snoT.reA pesn suoTlecoT +ua.reJJ:Tp 1e uau:eqsTl sluos pue
(C edl(t tod) pasn osTp ora/..t slod Taats Jo raqwnu TTeus v 'lZ
addt lod) slod uelteq pue (T ad^dl tod) slod eArqeeq (Z aTqp,I
ees 1 peldures sleoq aq1 dq pasn sedz(1 1od :o feru or,ll erarlr €:aq;,
'dpn1s s1q1 6u1:np poArasqo orear 9 o1 1 secuenbes
xTuo 'uoTlcnporlul erll uT peqj:csap pue (ssard uT) .TE-J3 uaro:g
z(q dpnls TeTlTuT aql uT pal.resqo sacuenbas 6u11:os xrs ar{1 J:O
METHOD 1. Assumes rock lobsters f rom each pot are sorted
randomly from thercacca box' and an est imate of
exposure t ime is obtained for each indiv idual .
METHOD 2. Assumes the last pot of animals added to a 'cacca
box' woul-d be the f i rst sorted and provides an
est imate of the mean exPosure t ime for animals sorted
from the layers of lobsters bui l t up from each added
pot: i .e. an average exposure t ime for each pot fuI l
o f an ima ls i s ca l cu la ted .
METHoD 3. Assumes the last pot of animals added to the 'cacca
box' is the f i rst to be sorted, as in Method 2' but
exposure t imes are est imated for each animal
indiv idual ly rather than on average exposure t ime for
each pot.
The distr ibut ion of exposure t ines ( in f ive minute
intervals) was calculated over al l boats monitored
and over boats using the same sort ing method.
Each boat monitored was equal ly weighted with regard
to catch rate by using percentages of undersize
handled rather than the actual number counted, the
percentage being weighted in proport ion to each
boa t ' s po t l i cence . Th i s p reven ts Poss ib le b ias
occurr ing through the select j .ve use of certain
handl ing methods by boats of a part j .cular s ize.
I
's.relsqoT {co.r Jeqlo AoTeq se^Tosueql
6u1c:o; Iq ,{ue1 ar{1 Jo s.reu:oc .ro ruo1loq eql 01 1a6 o1 pe1.r1
s:elsqoT >tcor pecnpo:1u1 ,{1neu z(ueur asec qcrqA uT , rxoq eccecr
e se pasn seA {ue1 lott e :o lrroT a.raA seler qclea uaqa per-lncco
suolldecxa dluo aqg, . rxoq eccpcr ael uT ruro; 01 pepual slod
alTsseccns uo.rJ sJolsqoT lcox g:o s:ede1 .uT lnd 1sn[ esoql pue
uAop .reaoT esoql uaeAlaq pet.rncco 6uTxTur aT11TT rxoq eccecr e
oluT lnd eJ€A s.relsqol {co.r ueqo , suoTleAJosqo uo.r.{ . sleoq eq1
p.rpoq uo pe.rJncco z(11en1ce 6u11:os /{or{ J:o Tapou aATlelueselda:
lsou aql aq 01 paA.rasqo se/vt lr esneceq ,Jaded srql
uT paluese:d sllnser eq1 .roJ srseq aql se pasn sen Z poqfa14
I f I RESULTS
Methods of sort ing rock lobsters f rom the pot
The locat ions at which the f ive sort ing methods observed in
this study were used are glven in Table 4, and associated pot
types are given in Tabl,e 5. The percentages of sampled boats
using the f ive sort ing methods rr tere as folLows:
1. 7 .88 sor ted d i rec t f rom the po t (sequence L) .
2 . 40 .08 so r ted a f te r each po t ( sequence 2 )
3 . 42 .68 so r ted con t i nuous l y ( sequence 3 ) .
4 . 4 .4* so r ted a t t he end o f a I j - ne o f po ts ( sequence 4 )
5 . 5 .2 * so r ted a t t he end o f a l j - ne o f po ts ( sequence 5 ) .
90 .4 * o f t he samp led boa ts used so r t i ng sequences 1 ,2 o r 3 .
Figure 2. shows the percentage of boats sampled using each of
the above sequences, compared to the previous study.
Percentages of undersize sorted using each method:
1 . Boa ts so r t i ng d i rec t f rom each po t hand led 7 .8 * o f t he
u n d e r s j . z e ( F i q . 3 ) .
2 . Boa ts so r t i ng a f t . e r each po t hand led 40 .48 o f t he
unders i ze (F ig . 3 ) ,
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:e.reA spoqlau 6u;1:os eql fo r4cea JoJ paurelqo seurrl afnsodxg
'selnuTu 0g-02 uTr{1Trq palJos ereA *O'Z 6utuleure:
eq? pue (t0.86 eATleTnunc) sa+nuTu 0z-gI uTqlTl|r pelros
e.reA Z0'Z ' (t0'96 a^TlpTnunc) salnuTu 9T-0T uTqlT! pal:os
araA tg'E '(tS'Z6 a^rleTnurnc) selnuru 0I-S uTqfTA pauos e:ettt
t0'g 'salnuTu g-0 uTqlTltr pauos €reru ezTs.repun aq1 f o 89'L8
(t '6T,f pue v9 6TqeJ, 'uorlcas sleoq TTe) eTdues erT?uo eql rod
spoqleur 6u11.ros eq1 Jo qcea JoJ azrs.repun Jo saurl af,nsodxg
'z(pn1s snotae:d eq1 01 pe:eduroc poqlaur
qcee 6u1sn pelJos azTs.repun 3o a6eluac:ad eq1 snor{s 'g a:n61g
't pue Z'f spoqleur 6u1sn pel.ros arao ezrsJapun aq1 Jo tZ'T6
'(e '6T,f) azrs.repun eq1
fo t6'g palpueq 'eurT e l:o pua er{1 1p 6u11:os 6ursn sleog '9
'(E '6T,i)
ezTsJepun eq1 fo tg't paTpueq 6urlros cTlef,Ja 6utsn sleog 'V
' (r '6T,r)
azTs.repun eql Jo ?9'g? pelpueq ,{1snonu11uoc 6ut1:os s1eo8 't
2 . So r t i ng a f te r each po t (Tab le 6A) - 97 .0 t o f t he unders i ze
handled using this method were sorted within 0-5 minutes,
1 . 0 8 w i t h i n 5 - 1 0 n i n u t e s , 0 . 5 t w j - t h i n 1 0 - 1 5 m i n u t e s , 0 . 5 t
w i th in 15 -20 m inu tes and the rema in inq 1 .08 w i th in 20 -40
minu tes .
3 . So r t i ng con t i nuous l y (Tab le 6A) - 85 .5E o f t he unders i ze
handled using this method, were sorted within 0-5 minutes,
7 .0 t we re so r ted w i th in 5 - l -0 m inu tes , 3 .5 t w i th in 10 -15
m i n u t e s , 1 . 5 * w i t h i n L 5 - 2 0 m i n u t e s , 1 . 0 ? w i t h i n 2 0 - 2 5
minu tes , 1 .5 t w i th in 25 -40 m inu tes and the rema in ing >0 .5 *
were sorted af ter 40 minutes.
4 . E r ra t i c so r t i nq (Tab le 5A) - 52 .0 * o f t he unders i ze
handled usj .ng this method, were sorte<i wi thin 0-5 minutes,
1 " 4 . 5 t w i t h i n 5 - 1 0 m i n u t e s , 1 7 . 0 t w i t h i n 1 0 - 1 5 m i n u t e s ,
10 .58 w i th in 15 -20 m inu tes , 3 .58 w i th in 20 -40 m inu tes and
the remaining 3.0* v/ere sorted af ter 40 mj.nutes.
5 . so r t i ng a t t he end o f a l i ne (Tab le 6A) - 47 .0 t o f t he
undersize handled using this method, were sorted within
0 - 5 m i n u t e s , 2 3 . 0 2 w i t h i n 5 - l - 0 m i n u t e s , 1 5 . 5 t w i t h i n 1 0 - 1 5
minu tes , 9 .5 t w i th in 1 ,5 -20 m inu tes , 4 .5 t w i th in 20 -25
minu tes and the rema in ing 0 .58 were so r ted w i th in 25 -35
minu tes .
The longest exposure t imes were observed on boats using errat ic
so l t i ng ( sequence 4 ) .
L2
ET
'r{:o6a1ec
6ur1:ros cTlp.ua eql uT uau.reqsTl 3:o e6eluac:ad aq1 u1 a6ueqc ou
ITTenx.rrA uoaq seq eteqr, 'r(1aa11cadset 4g'zl ox tz'Lz ruorJ pue
?6'ot 01 tz'9T uorJ 'e'T (€ acuanbasl tr1snonu11uoc 6u14:os pue
(z ecuanbas) 1od qcea :e11e 6u11:os ueuf,aqsT; ]o se6eluec:rad
aqq uT saseercuT a6:e1 ueeq osTe eAEq areqJ' "{1ea11cadsa:
go 01 t9'6 luo.rJ: pue tz'E of t9'Lt ruorJ 'e'T (9 acuenbes)
:ee6 3:o €urT e 6ur.de1e: ra+Je 6ur1:os pue (g acuanbes)
.rea6 g:o euTT e Jo pua eq1 lE 6utlros uauJaI{sTJ l;o e6eluecred
.,r aQ1 uT saseof,cep pe{.rPu uaaq eAeI{ e-raql 1eq1 (Z e'rn6Td) uaas
eq upc 1r 'Ipn1s luarrnc ar{1 uorJ aldures eql qlT/'r pa:eduoc uaqg
'19 ecuenbes) slod Jo euTT e 6u1Ie1a: relJe pel:os t9'6
'(g acuenbas) slod l:o euTT e Io pue eq1 1e palf,os t9'LE
(t ecuonbes) ,{11ec1le::a palJos *8't
'19 acuenbes) ITsnonurluoc palros tz'ZZ '€
. (z acuanbas) 1od qcea .re1]e pelros *z'974-,.
'11 ecuenbas) lod eq+ uo.I] lce.rrp pel.ros ?9'9
'v
'z
.I _ */ ,;3, ,!-.-,_...
, --1r:: sEr.r spoqleu buTlJos xTs eqll:o qcea 6ulsn sleoq
.{pn1s TPTITuT eq1 uI uecrad aql ' (g9- aTqe,I)
.,spoqlaur
Io qceeuTsn pa^raJO sabeluaprad
4.
E,III,I NOSIEVdIiIOC
----..-::l.ros e
(08-tt6r) Ion'rs lvrJrNr
p
I n t h e i n i t i a l s t u d y , o n l y 2 0 . 8 t o f
observed to use sort ing sequences 1
s tudy , 47 .88 o f t he boa ts mon i to red
sequences 1 and 2 .
boats monitored were
and 2 , whereas i n t h i s
were observed using
Percentages of undersize sorted by each of the sort inq methods
In the in i t iaf study (Table 68) , the percentaqes of the total
undersize caught by the f ishermen for each of the sort ing
methods were as fol lows :
1 . Boa ts so r t i ng d i rec t f rom each po t hand led - 6 .42 .
2 . Boa ts so r t i ng a f te r each po t hand led - 13 .08 .
3 . Boa ts so r t i ng con t i nuous l y hand led - 26 .2? . .
4 . Boa ts us ing e r ra t i c so r t i ng hand led - 4 .5 t .
5 . Boa ts so r t i ng a t t he end o f a l i ne hand led - 40 .9 t .
6. Boats sort ing af ter relaying a l j -ne of pots handled -
9 . 0 r .
A comparison of the resul ts of the in i t ia l study (TabLe 68)
with the resul ts of th is progranune (Table 6A) shows
considerable changes in the percentage of undersize handled by
so r t i ng techn iques 2 ,315 and 6 (F igu re 3 ) . The re has been a
dec rease f rom 9 .0 t t o 0 t f o r unders i ze hand led bv those who
I 4
:r
;:o e6eluacrad eq1 'poqleu 6uTuos cTle.rre eql :od 'ser:o6a1ec
alnuTu I snoT.rPA aq1 roJ pesodxe ezTs:epun 3:o sa6eluec:ad
rpTTuTs partoqs € pue Z'1 secuanbes 6u11:os seTpnls qloq uI
'lssard uT 'iE 16 uno:g rgBsT 'TlndeJ
pup uAo.rg) TeATArns ezTsrapun slceJJe ,(1e:eaes erou Jo selnuau
g T Jo poT.red a.rnsodxa ue pue r azls:epun peu.rnla.r Jo TeATA.lns Jo
pooqTTa{TT aql lcel:}e uPc a:ou ro salnuTu I Jo aurrl e:nsodxe ug
'(99 pue v9 saTqPr,) salnuru 9T uTqlTA pellos uaaq peq azTsrapun
aq1 Jo to'96 1eq1 puno; r(pn1s luef,fnc er{1 sPe.raqA 'salnuTu sl-o
uTqlTA palros ueeq pPq ozaslapun eql Io 89'€8 'Ipnls leTlTuT
aq1 uorg '.{pn1s luerf,nc er{l f,oJ TeA.reluT stuTl eues aq1 uTqlTla
pat.ros e.ra! tE'Lg aTTq^! 'Ipnls TPTITuT eq1 uT palros uaeq peq
azTsfepun fo 80'E9 'se?nuTur 9-0 uTqlTn : pauTq0roc spoqleur TIe
pue sleoq TTe :oJ: '(tB-886T) ,{pnls 1ua::nc aq1 pue (08-Lt6T)
,{pn1s 1et11ur aq1 JoJ 'seurTl e:nsodxe 6ur:eduo3 ',{1an11cedsar
seTpnls TETXTuT pue lueffnc aq1 qloq rof poqloul 6ut1:os
qcPe qlTA peleTcosse seurTl af,nsodxe eq1 aoqs g9 pue v9 seTqeJ,
se[T1 e.rnsocrxg
'1uec13:ru61suT e.reA 1p ecuanbas 1 6u,r1:os cTaEJ:e ,{q pue 11
ecuenbasl 1od qcea uo.rJ lce,ITp pel.ros azTslapun Jto e6eluecrad
eq1 uT sabueqc '8 9'€t 07 *z'gz I[or]: (e acuenbasl ^TsnonuTluoc
6u11:os esoql ,{q pue 'tt'g? ct1 tO'€T urolt (Z acuanbas) lod qcee
.rell:e 6ur1:os esoql ,tq pelpueq ezTsxepun Eo a6eluac:ed eq1 ur
eseercuT up uaoq seq o.raqI '(9 acuenbes) aurT P l:o pue eq1 1e
1:os oqu ueuuer{sTl: xq peTpueq azTsJepun JoJ tG'€ 01 t6'0t uorll
eseeJcep e pue (g ecuanbasl :ee6 :1eq1 6u1^de1a: JelJe pe1.Ios
undersize handled within 15 minutes var ied between the two
s tud ies w i th 89 .08 fo r t he i n i t i a l s tudy compared w i th 83 .5 *
for the current study. There was also a di f ference between the
s tud j -es fo r t he end o f l i ne so r t me thod , where 72 .58 o f
undersize were exposed for 0-15 minutes in the in i t ia l study'
compared rr / i th 85.5t for the current study. No comparison can
be made fo r so r t i ng a f te r re lay ing a l i ne o f gea r .
Trends with Pot Type and Sort ing Method
Table 2 shows the number of boats monitored at each anchorage,
using each of the seven pot types / combinat ions . The most
cornmon pot type l tas the batten Pot (pot type 2) ' which was used
exclusively by approxj-mately 73t of the boats. APproximately
1A of the boats sampled used only beehive pots (pot type 1) and
no boa ts used exc lus i ve l y s tee l po ts (po t t ype 3 ) . The
remainj-ng 258 of the sampled boats used combinat ions of these
three pots. When these f igures are compared to the pot types
used by boats monitored dur ing the in i t ia l stui ly, i t can be
seen that there has been a large decrease in the percentage of
boa ts us ing po t t ype 1 ( i . e . beeh ive po ts on l y ) f rom 33 t t o 1? ,
an increase in the percentage of boats using pot type 2, f rom
638 to 73 t and an i nc rease i n the pe rcen tage o f boa ts u t j - l i z i ng
comb ina t i ons o f po ts , f r om 4* to 26 t .
However, a compari .son betrreen the pot types recorded dur ing the
current study and the pot types indicated by f ishermen f i l l ing
ou t 1og books (Tab le 3 ) , i . e . app rox ima te l y 25* o f t he
commercial f leet, i t can be seen that there was an
underes t ima te o f t he pe rcen tage o f t he f l ee t t ha t u t i l i zes on l y
1 6
LT
rolcas u.raqlnos eq1 uT paleJluacuoc eq 01 pa:eedde z{aq1 q6noq+
,r{:eqstg aql }o uoTbaf, JeTncrqxed dup o1 pelJT.rXs€.r 1ou seti
slod aalqeaq ]o asn eq1 'P1Pp >1ooq 6o1 uro:4 '(t pue Z seTqe[)
treg i(1ag:eg of Txf,eqTex ruo:J pasn af,P slod uel1eg ',,{:aqs1;
aql uTqlTA esn lod uel1eq Jo uoTlnqT:lsTp aq1 01 lcadser
q1T!r slTnsa: {ooq 6o1 eq1 q1T/{ TT3A sareduoc ,{pnls 1ua:rnc eqf
'ezTsf,epun pe:n1dec aq1
Jo tZ'f6 peTpupq pue aldues aI{1 Jo St'06 ^q posn a:aA sacuanbes
6ut1:os aa.rql asaqf ',(:aqs1g: altr1 Jo uoT6ar f,eTncTlf,Pd
due o1 po?cT.r1se.r fou ereA g pue Z'I secuanbes 6ut1:os
lpr{l Aoqs slTnsal aq6 'spoqleu 6uTlJos snoTf,EA eq1 6u1sn aq o1
polrasqo e6e:oqcue qcee 1e sleoq ;o slaqunu aqf sAoqs t aTqe;
'1 acuanbas 6u11:os asn o1 pepual slod earqeaq ^d1uo 6u1sn sleoq
leq+ pel.resqo ser.r 1t ,{pnls TPTITuT aq] uI 'g ecuanbes pesn
(T ed^l lod) slod e^.tr{eaq 1sn[ peq 1eq1 paldures leoq Iluo aqg'
't pue z ecuanbes 6u11:os.pasn slod ue11eq 6ursn sleoq lsouI
, f,a^arrroE :pa^Jesqo spoqlau-6uT1Jos aATJ eql qlTA palercosse3*
sen 'pesn edl(l uoururoc fsour aq1 ' lZ ad^7 1od) 1od uaxleq
eq,tr 'edIl +od :e1nct1:ed due o1 palcrJlsar xou ola^r spoqlaul
6ur1:os 1eql s:eadde 1r 'pedoldura spol{1€ur 6uT+.ros eq1 puP pesn
sad,{1 1od aql qfTA pe:olTuolu sleoq Jo f,aqunu eq1 slaoqs I aTqe,I
',{11q611s ,{1uo pa.ra3:31p slod uallEq 6ursn ueur:eqst;
3:o e6eluac:ad eql eTTqA 'Sujnla.r )tooq 6o1 q11n paf,eduoc uar{A
slod l:o suorleuTquoc 6uTsn sleoq Jo sJequnu :a1ee:6 pal:esqo
Ipnls s1q6 '.f,pn1s sTqx uorf g1 o1 pasoddo se slod aalqaeq r(1uo
ezTTTln X91 Xleleurlxordde 'su.rn1e.r >1ooq 60T uro:d 'slod o^Tqeeq
of the f ishery. A greater var iety of pot types appeared to be
used in the region Cervantes to Two Rocks than in other areas
o f t he f i she ry (Tab le 2 ) . The greatest variety of pot types
was used by boats at Two Rocksi sj-x of the seven pot
types / combinations were used, though the same diversity was not
seen in the log book re tu rns (Tab le 3 ) .
General Observat ions
The rcacca box' , i ts construct ion, posi t ion on the boat and any
special features var ied widel-y amongst the boats. The type of
rcacca boxes' observed on boats incLuded: metal f rame with
metal mesh or synthet ic mesh sides and bottomt orange plast ic
prawn baskets; f ibreglass boxes; wood- f ibreglass . conposi te
boxes; wooden boxes; aluminium boxes; plast ic tubs, and box
sides with the deck forming the bottom of the box. Many had
rubber mats, carpet or hessian bags on the bottom. Several
boats.had boxes with special features. One boat was documented
to have sprays in the 'cacca box'1 one boat used a wet tank as
a t cacca box r ; ano the r used p las t i c t ubs con ta in ing sea wa te r
that was changed regular ly.
The pos i t i on o f t he ' cacca box ' on the f i sh ing boa ts va r ied ,
most being below the t ippert others were on the opposi te s ide
o f t he deck to the t i ppe r o r am idsh ips . On 14 o f t he 115 boa ts
monitored, the 'cacca boxr was beneath a coachtop (wheelhouse
roof) extension; which provided some shade.
Several f ishermen stated that when they
numbers of rock lobsters they would sort
1 8
r ' rere catching large
e v e r y 3 t o 5 p o t s
6T
sauTl ernsodxa asee:cur ,{eur a:npeco:d slqX lnq ,pa^IoAur efeA
sTeuTue l:o slequnu 11erus ,{1uo tr11enso . azTs.repun :o azTs e.reA
Iaql :aqlaqA eprcap pue uaql e6ne6 plnoc l:TesuTq :eddrls aq1
TTlun 'eurTl 3:o spol:ad pepuelxa .roI pTeq aq pTnora ezrs 01 asoTc
araA 1er{l azTslapun 1eq1 suoTsecco Tp.ra^as uo pe^.resqo seA 1I
'pacuel:edxe
a:e!a salp.r qclec ! oT ueqA (uefleq) z ed^l lod q1r,ra suoTsecco
rlueur uo poA.rasqo se!,r ( I acuanbes 1 1od eq1 uro:;: i(11ce:1p 6u11:og
. (I.raqsTl: aq1 Jo aseqd , sel.Trtrarr aq1 6u1:np
'6'0) spueq-{cep oJoru ro oarl r(oldure qcrqrrr sleoq uo ,qc1ec
q6Tq Jo spol:ad 6u1:np ^TsnonuTluoc 6ut1:os pueq-{cep eug
'6u11:os spupq-Icep e-roru .ro oA;
.6u11:os pueq-{cep pue :add11s aq+ qlog .E
',{1uo 6ur1:os pueq-Icep V .Z
'.(1uo 6u11:os :edd11g .T
: buTl.ros uT paAToAuT
Aa.rc Jo suoTlEUTqUOC luaJaJJTp le.reAes e.reA eJeq&, . rXoQ
eccecr aq] :o 1od eq1 .dldure o1 ue)|ef aurTl eq1 pelcaJJe z{11ea:6
s.ralsqoT >[cor aq1 6uTl.Ios uT poAIoAuT suosred Jo. raqunu oqfi,
'n
pecnpa.r 6u1qc1ec ueqA e to Z'T secuanbes 1:os
req+e: ,IInJ se.64 rxoq eccecr .rTer{l :a^euaqA Jo r(
'sJoqumu
6ursn ueql
7 ecuenbes 1
for sort ing nethods that normal- ly do not
pe r iods (e .9 . seguences 1 and 2 ) . Th i s
e t a I . ( i n p r e s s ) .
have extended exposure
was also noted by Bro\'in
.t
Boats f ishing in amongst breakers (white water) , as of ten
occurs hr i th jet boats woEking the Ablolhos IsLand's, were$"t
observed to change sort ing methods in di f ferent s i tuat ions.
?hey woulcl switch from their normal sort ing sequences L,2 or 3
to 4 or 5, while working in dif f icpfog$reas. !:tr
I'
The distances that undersize rock lobsters were displacpd was:
di f f icul t to est imate. Some f j .shermen took great care to
return the undersize back into the area from where they were
captured, which unfortunately in some cases resul ted i 'n
sLight ly increased exposure t imes.
IV DISCUSSION
The object ive of the current study t t ;as to compare the
p ropor t i on o f f i she rmen cu r ren t l y (1983-84 ) us ing each o f t he
sort ing methods to the proport ion observed in the in i t ia l study
(1977-80 ) . Th i s wou ld de te rm ine whe the r t he l a rge -sca le
ealucat ion progralnme undertaken by the Fisher ies Department
(1981-82 ) , t o a le r t f i she rmen to the e f fec ts o f poo r hand l i ng
pract ices on the survival of undersize, had helped to
signi f icant ly change the sort ing methods used 'and thereby
reduce the mortal i ty of handled undersize. From these resul ts
further recommendat ions to improve undersize survival could be
made .
2 0
TZ
6u11:os ruo:;: a6ueqc o1 ,{1a:111 eJe ueur.reqsr; ,q6'rq a:e
selEJ qclec uer{M '1q6nec o:p ezrsropun Jo staqunu 1sa6:e1
aql uaqn 11r.rdg-qc:eq pue .requeJeq-.raquaAoN) sa1p.r qclpc
q6Tq fo spoTred 6u1:np ,{11aeaq a:or:r paldues I pnls TeTlTuT
eq1 esneceq sT sTq,tr .Ipn1s TeTlTuT oq1 ot pa.reduroc
palEuTlse.ra,ro aq ,{eur poqleur 1od qcea :e1g:e 6ut1:os
aq1 pup paleurlsa.repun eq trer:r spoqlaur 6ur1:os snonuTluoc
aq1 6uTsn trpn+s luar.rnc ar{1 ur poArasqo uaurer{srJ Jo
uo11:odo:d aq1 leq1 sr seTq Jo ecJnos alqrssod IsJTJ aqtr .I
: lssa:d u1 .Je= 1a
uAo.rg) seeJe Jo r?qunu p uT serq 01 esr.r aa16 plnoc ,{pn1s stql
ur pasn senbtuqcel TEcTlITpue aq1 ,Ipnls TeTlTuT aql qlTrlr sV
'sTassaA .rTaql pteoq€ JJpls qcteese-r {oo1
I16u111rru pue alTlerado-oc lsour a.raA par{ceo:dde uaur:eqsTJ TTV
'(ssa:d uT 'TE ]a- uno.rg re 86I ,rlndeJ pup uAo:g) (surJ 0Z) ur
9e ueql ssal sqldap uT'e'T ,1se1ee:6 selr azrs.rapun 6urqclec ;:o
tr111tqrssod eq1 e.raqA sqldep ur 6utlrola uau.reqsrJ Jo uor?ceTas
uopueJ e pa^ToAuT eldrues aqg, .1eaTJ .ra+sqoT 1co: eq1 Xq
paqsTf eaf,e aJTlua oq1 lsoule uo:J uoseas euo .relo paldures sen
leeTJ ferc:auuroc eq1 Jo g0.gI se ,r{:eqs1g: aql }o aalleluesa:da:
pe.raprsuoc aq osle uec ,{pn1s fua:f,nc aqtr . r{:aqsr; a.rrlue
aq1 fo a^rlpluasa.rda: pe:eplsuoc seA srql pue ,09-6t6T pue
6L-BL6T ^ebttdi , suospas 4ip.rr{1 .relo ,arlueuaf,d pue s{cou oAt,
'1uTod e6pe1 .r{eg ueTrnf , fud flf f c-e.rebuoo ,spueTsI soqforqv
'TJJeqTpX :seberoqcue uelas 1e ,lealJ 6u1qs1g: eq1 fo g9I
paldues (ssa.rd uT) 'TE l5 uno:g .a1q1ssod se dlasolc se trpn1s
leTlTuT eq1 fo spoqleu aq1 peAoTTo; ,{pn1s luerrnc eq1 lBq1
TeTluessa serrr lT elqe:eduroc z(11car1p aq 01 saTpnls o/trl aq1 .r6d
after each pot to cont inuous sort ing, because they are not
able to keep pace with the large number of animals comj-ng
aboard. This would tend to underest imate the average
exPosure t ime calculated for undersize'
2. The second possible source of bias runs counter to that
descr ibed in I above. Fishermen who f ish exclusively
beehive pots (pot type l ) were under-rePresented in the
current study (see research 1og book data Table 3) ' These
f ishermen predominant ly sort direct f ron the pot (sort
type l ' ) which gives the shortest exposure per iod of any of
the sort ing techniques (Tables 7 and 8) '
T h e s e c o n d s o u r c e o f b i a s w o u l d o f f s e t t o s o m e d e g r e e t h e
increase in exposure t ine caused by underest imat ing the
cont inuous sort ing method dur ing per iods of high catch
ra te d i scussed i r r I above . The re fo re i t i s cons ide red
that the resul ts are 9eneral ly representat ive of the
cornmercial rock lobster f leet '
The resul ts of the current study show that approximately 4.0?
of the undersize handled by f ishermen, are exposed for more
than f i f teen mrnutes (Table 6A). This percentage is a marked
reduct ion on the 16.5t exposed for more than f i f teen minutes as
determined in the in i t ia l study (Tab1e 68) ' The reason for
this reduct ion can be direct ly at t r ibuted to improvement in
sort ing methods. In the in i t ia l study the greatest proport ion
o f f i she rmen 37 .6? so r ted a f te r p t l l i ng a l i ne o f po ts (enc l o f
l i ne so r t j - ng -seguence 5 ) and 9 '58 so r ted a f te r re lay inq a l i ne
o f po ts ( sequence 6 ) , wh ich resu l ted i n ex tended pe r iods o f
z z
--
ez
uro:; tr11ce:Tp lJos .,t11ueu1uropa:d slod eaTqaaq 6u1sn uaur.reqsrS
,pe1e1s trlsnolaard se ,.rezraAoH . (g pup Z sefqed,) ualleq
tr1uo :o uellpq pup alTr{eeq }o suorleuTquoc of slod aarqaeq
z(1ea1sn1cxe uro:3: r{errae , sod^f 1od u1 se6ueqc eq1 aq p1noJ
'spoqlau 6ur1:os snoT.rel eq1 6ursn uau-raqsr; 3:o uorl:odo.rd aq1
ur se6ueqo paltasqo eql 01 pa+nqrJluoc aneq Xeur feql Jolce] v
'espc aql aq 01 punoJ lou seA srqtr .poTJed aurl eur€s eql Je o
pefJos aq pTnoA ezTsrepun go a6eluec:ad :a1ee:6 p 1eq1 palcadxa
aq pTnoc 1T ,uoTlpJado Jraql 3o peads aql pesea.rcuT ecuTs
peq ,{eq1 pup oTqeoTlce.rd se lseJ se 6u'r1:os ueeq 1ou peq Xeql
dlsnorrra:d g:1 'aTqpcrlceJd sr se lseJ se 6u11.ros a-rp poqlaur
qcea 6ursn ueuJaqsrJ aq1 1eltl s1sa66ns srq; .:e1ru:rs .{rezr
ere por:ad euTl afnuTur aATJ qcea ur pal.ros (g9 pup v9 saTqeJ,)
azrs-repun yo sa6eluac:ed eq1 1eq1 uees aq uec 1T ,sarpnXs
qloq ur poqlaur 6ur1:os qcpa JoJ saulTl af,nsodxa 6urteduoJ
'(v9 aTqeJ) spoqlaur o^{f eseql asn ueuraqsT]
jo ZLV ,llaleurrxo:dde Aou i (99 aTqpJ,) spoqlaul 6u11:os on1
asaql pasn ueuJeqsrJ Jo t0Z .dlaleurrxo:dde ,trpn1s TeTlTur.aql
uI 'ueureqsT; TIp ^q pesn spoqlaur 6ur1:os aqf e.ren lod qcea
:a13:e 6u11:os pue 1od aq1 uo:J loa.r-tp 6u11:os ]T TaAoT elqtssod
lsaAoT eql 01 pacnpa.r aq pTnoc , (ssard uT .TE'l5 uaro:g !9961
'rf ndEJ pup uAo.rg) ,{ltTeq:our pacnpuT z{:aqstg: o1 6ur1nq'r:1uoc
stolceJ .roIeu ea:q1 aq1 ,luautoceldstp pue a6eurep ,aJnsodxg
'(v9 aIqe,l) spoqlaui buTlros onl asor{1
6urdoldua uau:aqsrJ aql fo g7g .dlaleurxo:dde qlTA ,,{Tsnonurluoc
-ro 1od qope falJe 1.ros ,\ou uauJar{sr; lto uoTl.rodo:d 1sa1ea:6 aq1
puno]: ,{pn1s luaJJnc ar{J, '(s9 alqe,r) azTs.rapun eql .ro] eJnsodxa
I
I
the pot and some of them appear to have cont inued this pract ice
with their , nel / gear (batten pots) , as the proport ion of
f ishermen sort ing direct ly f rom the pot has in fact increased
during the per iod betr , reen the two studies.
An addit ional factor that may have caused. an overest imate in
the change frorn longer to shorter sort ing methods, is that,
unl ike the in i t ia l study, conducted over 3 seasons, the current
study was conducted over 1 season and could not concentrate
monitor ing on the per iods of highest catch rate. In the
current study 12 boats ( l -Ot) were monitored dur ing the per iod
November-JaDUdf, ! r the rwhitesr f j -shery, and per iod of highest
ca tch ra tes , wh i l e i n t he i n i t i aL s tudy 53 boa ts (42? ) (B rown
et al . in press) were monitored dur ing the same per iod. This
could have led in the current study, to an overest imate of the
proport ion of f ishermen using the f i rst t \4ro sort ing methods
(Table 6A), which give the shortest exposures. Durj-ng per iods
of high catch rates a proport ion of the f ishermen observed
using sequences l and 2 would have reverted to one of the
methods giv ing considerably longer exposures (usualIy
cont inuous sort ing - sequence 3). An example of th is is
f ishermen who use sort ing af ter each pot dur ing per iods of 1ow
catch rates and cont j -nuous sort ing dur ing per iods of high catch
rate. Therefore the size of the change to sort ing direct f rom
each pot and sort ing af ter each pot may not be as large as i t
appears, especial ly for the lat ter method. Therefore the
improvement in handl ing methods and hence survival of undersize
observed in this study should be viewed as the maximum
improvement in handl ing pract ices that would have occurred.
2 4
sz
.rTaqf J:o 1sour u.rn1a.r Ieul (t9.77) IlsnonuTluoc lros oqr"r
uau.rarlsr4 l:o dnor6 a6re1 eq1 Jo euos .,(111e1:our luecr;tu6rs
asnec pTnoc 1Eql poqleu e pesn (*z.zgl uauuaqsTJ 6urureuar
eq,l '6u11pueq 01 enp z(1t1e1roru azrururu leq1 spoqlew 6uTlJos
onl aql .... ,qod qcee Jal}e :o lod eql uo.rJ lcetrp 6ur1:os
a:eaa paldures asoql Jo (t;.zt) ;Teq upql ssaT ,1od qcea f,alJe
6u11:os o1 6u16ueqc ueuraqsTl: .{ueru q11aa ,sacTlce.rd 6u11pueq
uT lueueaordurl 1uec1;1u61s e 01 peT aleq sa6ueqc aq1 q6noq11v
.esec aq1 TITIS sT sTqf pue ,ueu.raqsr] aq1 Jo
apnlTlle aq1 .d1:ea1c sen spoqlau 6ur1:os 6u1u1ur:a1ep uT Jolcel
1uec1g1u61s lsou eq1 , (sserd uT) .TE lE uano:g uT pale1s sV
'1uaur1:eda6 seTJaqsrg aq1 r{q un_r
ueeq aaeq 4eq1 saunuet6o:d uollecnpe alrsrrelxo aq1 ol pelnqT.rl1p
aq I1a6:e1 uec se6ueqc eqg, . O1-LL6I uT t99 o1 pa:eduoc salnuTu
9I uTr{lTA.peTpueq 6u1aq ezrs:epun Tfe Jo *g.Zg 01 peT ser{
sTq,t '(e^oqp peuTTlno serq l:o sactnos alqrssod eql alTdsap)
azTsJapun 6u11pueq sp.rEl"tol sapnlT11p stueuJaqsrJ ur luaueao:dur
luec1g:1u6rs e ueaq seq eraqf 1pq+ uAoqs seq .{pn1s lue:.rnc oq1
'(ssef,d uT) 'TE $ uno:g go Ipnls TpTlTuT er{l 01 dn-arro11oE e sg
SNOISOTCNOC A
'(.re1E^l
ltroTTeqs uT selnuTu o^r1 ^TelEurTxo:dde s errn 1od p {ce4s pue
lTpqe: ,f1dua ,TTnd 01 eur11 a6e:eae eq1) :ee6 6u11pueq Io aleJ
ralsef .d11uec1g:1u6Ts e uT palTnser potllow 6uT1.ros oN .puno]
serra sdno:6 cTuqle Jo sazfs asuecTT ,sedr{l leoq reTncrl:ed qlrn
sanbluqcel 6ur1:os 6u1:1ut1 spue.rl ou ,dpn1s TeTlTuT er{l ur sv
undersize to the water as quickly as those who sort af ter each
pot when catch rates are Io! t . However, hThen catch rates are
high, the cont inuous sort ing method cannot keep up with the
constant addi t ior , of more animals to the 'cacca box' , and under
these condit ions f ishermen who sort cont inuously wi l l g ive the
undersize longer exposures and hence produce signi f icant
mortat i t ies. Notwithstanding the improvements that have
occurred in handl ing pract ices, the mortal i ty that could be
occu r r i ng ( i . e . even i f on l y a t t he ra te o f 258 o f t he
mortal i t ies that were occurr ing before the educat ion progranme
was in j . t i a ted ) , t he l osses wou ld s t i l l be i n excess o f $A3
mi l l i on annua l l y (1984-85 p r i ces ) ,
Recommendations to Further Reduce F i she rLLll1gLE4e.Lill
Design of a new escape gap that wi l l s igni f icant ly reduce
the number of undersize brought on board. Quite obviously
the root of the problem is that rock lobsters which are
too smal l for sale are retained unnecessari ly in the pot
and taken from their sea floor environment artd exposed out
of the water on the deck of a boat. Reducing the capture
of undersize ( through a more ef fect ive escape escape gap)
should be seen as a f i rst pr ior i ty. This has been the
subject of a separate invest igat ion.
The second pr ior i ty, is that any undersize captured should
be returned to the water in the shortest possible t ime
(i .e. by sort ing al l the animals f rom one pot before the
next pot is pul led). There are only two sort ing methods
which guarantee to minimise losses due to handl ing: (a)
l - .
z o
LZ
BZT-E0T ,7 Q5iEaE{ sar.ror.tsTd
'E€s aql 01 uauraqsTJ ^q pau-rnlaf, (e6roeo) Fn-ii6-f5
surlnupd ra+sqoT {co.r u-ralser'r azrsJepun ;o e:nldeca:
eq1 6urlceg:JE s.rolced . (tg6I) .N ,TlndeC pup -S.U ,unorg
SSJNSUSdEU IIA
'pund luaudola^eq
pue qc.reesaU sarf,aqsrd ueTTe.rlsnv ulelseM aq1 uorJ 1ue:6 e
r{q pa1:oddns se.lr qJreasar srqtr . eurue:6o:d aq1 uT paledrctl:ed
oqn ueu.reqsrl: esoql TTe pue 1d1:csnueu aq1 6u1dr{1 :o3
scpesl 'I^l sfhl 'suoTlsa66ns 1ng:d1aq .dueur 6ur:e;:l:o pue 1dT-rcsnupul
aq1 6u1pea: ITtpcTlTrc .roJ >1cocupg .V.C f,q ,6ursseco.rd
elep 6u1s1a:odns roJ fIeH .N Jhl /{JoA s1q1 6u1:np acuelsrsse
TecTuqcal .roJ qqnqc . J f,o {ueq1 01 a{TI plno!'/r sroqlne aqJ,
s.tNsr{EDcET[,toNxcv IA
' suoT lppuauuooer .raqlo .roJ (sseJd uT) . Te 1a uAo.zg eas . V
.ace1d sa1e1 6u11:os
eTTqA fea pup Tooc 1da1 a:e sJalsqof aq1 os , rxoq pccecl
eq1 fo doq aq1 punote pa11TJ aq plnoqs s^prds .suorlrpuoc
aTqTssod lseq aql :apun 1da1 eq pTnoqs ezrs.rapun er{1
prpoquo ,{pls JaTtq Xue 6u1:np 1eq1 sT I11:o1:d prTql aq,t .€
'pe11nd sr 1od lxeu aql aJol:eq
1od auo uoJJ pa1:os e.re ,azrs.rapun pue ezrs qloq ,sJalsqoT
aq1 TTe asec qJee uI .parldule ueoq seq 1od eq1 :e1ge
,{1a1e1paurur1 6u11:os (q) pup 1od aq1 r::o:3: ,{11ca:1p 6ur1:os
Brown , R .S . and Capu t i , N . (1985) . Fac to rs a f fec t i ng the
growth of undersize western rock lobster, panul j . rus cygnus
(George) returned by f ishermen to the sea. Fish. Bul I .
8 3 ( 4 ) .
B rown , R .S . , P r i nce , , J . , Capu t i , N . and J . . f enke . ( i n p ress ) .
Fishery induced mortal i ty of the und.ersize western rock
lobs te r . F i sh . 8u11 . Wes t . Aus t .
2 8
6Z
. TV.IO,I SH.I NI OSCOTJNISUV CINV S,ISXCYE€I NI SH,INOI,{ OJ USJstI S.IE'XJVU€I NI SESa!{ON r
1V,IO,t
ruvnNvf
tuvnEss,i
ruvoEsE-,i
.r.uvoNvf
ruvnNvf
TIUdtV.,
TIEdV
HJU1IW
HCUV[il
HCUVht
rEvousg.il
Truatv
IVN
I'v
TABLE 2
NUMBERS OF T4ONITORED FISHTNG BOATS UTILIZTNG EACH POTTYPEICO!,IBINATION AT EACH ANCHORAGE. TOTALS ARE COMPARED
WITI1 PREVIOUS RESULTS.
POT TYPE*ANCHORAGE
KALBARRI
PORT; GREGORY
RAT ISLAND
LITTLE BAYAND HORROCKS
GERALDTON
DONGARA
SANDY CAPE AND.]URIEN BAY
CERVANTES
LANCEL IN
LEDGE POINT
TWO ROCKS
QUINNS ROCK
WH ITFORDS
FREMANTLE
SAFETY BAY
I
i f ,
f,
6
9
8
I 7
5
J
1
1
J
J1
1
1
I
1
TOTALS x = 115 8 4
AS PERCENTAGE(NEAREST WHOLE
IT{ITIAL STUDY
OF SAMPLEPERCENT )
RESULTS
7 3
6 3
I
0
POT TYPE: Beeh ive o r s t i ck po t .
Ba t ten o r s la t po t .
S tee l po t .
Combinat ion of beehive and batte 'n pots.
Cornb ina t i on o f beeh ive , ba t ten and s tee l po rs .
Combinat ion of beehive and steel pots.
Combinat iorr of batten and steel pots.
3 0
IE
z s1€tv,r oJ Ea,ltsE 'sNor,rdruJsucl sd&r ,troit Eo,!l *
9I 9L(,tNscuud sroiil,t,tsuuvsN)q9v,rNucusd v sv sTv,ro,t
zl8tT0gt6T = 3 STV,IO'I
t
7
I
I
TT
OT
ET
I
€T
5n
ZZ
z
ZI
z
7
z
HTOOS CINV HvuNqNVW
.Lt .L,IS.{VS
sT,tNvnsu,tSqEO,T.IIH},I
XCOU SNNIOO
SXJOU OM.I
OUT€IVSS
TNIOd UOAST
NITUCNVIoNv 'sr s9qs!,1
'sf Nsau9qNv su,rNvAusc
.LI NSrUO.eqNv silvc ^qNVs
salvJ ^oNvsO,I 'SI ST9VSEI
'sr sTtvsao,r Vuv9Noq
NO,IOTvuS9
sxcouEoH ctNvTVg SI.ITIT
Ino9EU9 &UOd
IUUV€IaVX
s9VuoItcNv
+XdI& &Oil
' sgvuoltcNv Hcvs ,rv sdr,r ,loil ilcvE eNT z rTr,rn 'sNuo,tgE xoo€t 9or €g6r us€u{sDac lirou,E 's,rvog gNrlrsrJ JIo susgwnN
e sTsv,r
TABLE 4
NUMBERS OF BOATS AT EACII ANCHORAGE USING SPECIFIED METIIODS. TOTALSHAVE BEEN COMPARED WITII EARI.IER RESULTS.
SORTING METIIOD*ANCHORAGE
KATBARRI
PORT GREGORY
RAT ISLAND
LITTLE BAYHORROCKS
GERALDTON
DONGARA
SANDY CAPE ANDJURIEN BAY
CERVANTES
LANCELIN
LEDGE POINT
TWO ROCKS
QUINNS ROCK
WH ITFORDS
FREMANTLE
SAFETY BAY
1
o
8
tt
21
1
z
1
7
l-
1 0
J
3
1
6
4
1
6
1
1
1
TOTALS x = 115 4 94 5
AS PERCENTAGE OF SAMPLE
INITIAL STUDY RESULTS
4 0 . 0 4 2 . 6 4 . 4
1 5 . 2 2 7 . 2 4 . 8
7 . 8
5 . 6
5 . 2 0
3 7 . 6 9 . 6
*SORTING METHOD: 1. Sort ing direct ly f rom the pot.
2. Sort ing af ter each pot.
3. Sort ing cont inuous ly.
4 . E r ra t i c so r t i ng .
5. Sort ing at the end of a l ine of pots.
6. Sort ing af ter reJ.aying a l ine of pots.
3 2
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F EzU J E9 ( )F a '9 :i : ( , )< ff:f
3SORTIN6
3 1SORTING METHOD
Figure 2
IMETHOD
B.
-lnit iol Study ( 1977 - 1980 )
-Currcnt Sludy (1983 - 1984 )
3 6
LL
€ €rnbrd
OOHl3l',| gNUtOS
orq
czozR
D
ffi$m vr z-
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PERCENTAGEOF UNDERSIZE HANDLED
8 8 3 R 8 8 g 8 R e o
(uq)
IFt\O)
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