A bait comparison study in the Newfoundland and Labrador snow crab (Chionoecetes opilio) fishery: does Atlantic herring stand a chance against squid?

Transcription

1 A it comprison study in the Newfoundlnd nd Lrdor snow cr (Chionoecetes opilio) fishery: does Atlntic herring stnd chnce ginst squid? Prepred y: Scott M. Grnt & Wde Hiscock Centre for Sustinle Aqutic Resources Fisheries nd Mrine Institute of Memoril University of Newfoundlnd P.O. Box 9, St. John s, NL, AC R With industry prtner: High Tide Enterprises Anglicn Cemetery Rod, Portugl Cove, NL, AM H Sumitted to: Newfoundlnd Deprtment of Fisheries nd Aquculture P.O. Box 7, St. John s, NL, AB J Decemer 9

2 A it comprison study in Newfoundlnd nd CSAR P- A it comprison study in the Newfoundlnd nd Lrdor snow cr (Chionoecetes opilio) fishery: does Atlntic herring stnd chnce ginst squid? Prepred y: Scott M. Grnt & Wde Hiscock Centre for Sustinle Aqutic Resources Fisheries nd Mrine Institute of Memoril University P.O. Box 9, St. John s, NL, AC R Tel: (79) 77-, Fx: (79) 77- With industry prtner: High Tide Enterprises Anglicn Cemetery Rod, Portugl Cove, NL, AM H Sumitted to: Newfoundlnd Deprtment of Fisheries nd Aquculture P.O. Box 7, St. John s, NL, AB J Decemer 9 ii

3 A it comprison study in Newfoundlnd nd CSAR P- Tle of Contents Executive Summry..... Introduction.. Mterils nd Methods..... Results Discussion.. Acknowledgements Literture cited... Tles..... Figures Correct cittion for this report: Grnt, S.M., nd Hiscock, W. 9. A it comprison study in the Newfoundlnd nd Lrdor snow cr (Chionoecetes opilio) fishery: does Atlntic herring stnd chnce ginst squid? Centre for Sustinle Aqutic Resources, Fisheries nd Mrine Institute of Memoril University of Newfoundlnd nd Lrdor, Cnd. P-, iii + p. iii

4 A it comprison study in Newfoundlnd nd CSAR P- EXECUTIVE SUMMARY Squid is the preferred it in the Newfoundlnd nd Lrdor snow cr trp fishery. The vrile rising costs of squid hve t times cused fishermen to supplement squid with Atlntic herring which is less expensive option however, the economic enefits re uncler. The current study compred the ctches of snow cr in four it configurtions (tretments) of squid nd/or herring. One it configurtion ws the quntity of squid typiclly used to it trp ( ls,.9 kg), two of the it configurtions comprised herring s n equl quntity ( ls herring) or equl monetry vlue ( ls/. kg herring) of ls squid, nd the fourth it configurtion ws l : rtio of squid nd herring. Ctch rtes of the four it configurtions were ssessed under simulted commercil conditions y using seprte fleet of trps for ech it configurtion (i.e., four commercil fleets) nd through the use of science fleet, which ws comprised of five replictes of ech of the four it configurtions. The study ws crried out on snow cr fishing grounds in Conception By from - July 9 where huls were conducted with ech of the five fleets (four commercil nd one science) for totl of 7 huls. This study demonstrted the importnce of squid s it in the snow cr trp fishery, the importnce of the quntity of it when herring is used lone, nd suggested slight dvntge in ctch rtes with it comintion of herring nd squid in commercil fleets. The l : rtio of squid nd herring nd ls squid performed est overll in oth the science nd commercil fleets exhiiting totl ctch of legl size hrd-shell cr over huls of ech it configurtion tht were.-% higher thn ls herring nd -% higher thn ls herring. In the commercil fleets, the l : rtio of squid nd herring nd ls squid were the only it configurtions to hve significntly higher ctch rtes thn ll other it configurtions, which they did in % of the comprisons. Commercil fleets ited with l : rtio of squid nd herring significntly outperformed ls squid in % of the comprisons while ls squid significntly outperformed ls : rtio of squid nd herring in % of the comprisons. When verged over three weeks of fishing, the men percent contriution of sulegl mles nd legl size soft-shell cr to the totl ctch (kg) did not differ significntly etween it configurtions. Overll, this study demonstrted tht commercil fleets ited with l : rtio of squid nd herring performed mrginlly (.% higher ctch) etter thn fleets ited with ls squid nd given the lower price for herring provide compelling evidence to promote the use of oth it types. The 7 snow cr stock ssessment indicted the totl trp effort in the Newfoundlnd nd Lrdor snow cr fishery (i.e., NAFO JKLNOPR) ws.9 million trps. A simple cost enefit nlysis sed on it costs in 9 nd sustitution of ls squid with l : rtio of squid nd herring throughout the fishery suggested there could hve een svings in the order of $. million to the hrvesting sector of the snow cr industry in 7. Although herring lone my not stnd chnce ginst squid, it tht comines n equl quntity of herring nd squid hs the potentil to provide significnt svings to the hrvesting sector without negtively impcting the ctch of legl size hrd-shell cr.

5 A it comprison study in Newfoundlnd nd CSAR P- INTRODUCTION Investigtions compring the performnce of different its in sttic fishing ger re dunting tsk. Severl fctors my ffect the trget species ehviour towrd specific it plume such s; intrinsic sensory limittions relted to sex, condition, nd stge of the life cycle, temperture nd metolic processes, current direction nd velocity, turidity nd light levels, prey vilility nd levels of stition. Further, severl fctors cn influence ctch rtes in ited trps other thn chnge in it type or quntity of it. For exmple, differences in undnce of the trgeted species within the effective trp re of n individul trp or fleet of trps my influence ctch rtes. Fctors influencing locl undnce include sustrte type, depth, temperture, food vilility, nd previous levels of fishing pressure. Complex interctions of fish with ited fishing gers hve een reviewed y Stoner () nd reserch compring cpture rtes of different its in trp fisheries is sprse (Wlsh, Dle et l. 7, Archdle et l. ). The purpose of this study ws to determine whether Atlntic herring (Clupe hrengus), less commonly used it in the Newfoundlnd nd Lrdor region, cn e s effective t ttrcting nd cpturing snow cr (Chionoecetes opilio) s squid, the more commonly used it. The squid used s it in the regions snow cr fishery is not only imported nd food grde, ut lso sustntilly more expensive then Atlntic herring which is cptured loclly from five resident stocks. Anecdotl informtion from the Newfoundlnd nd Lrdor region suggests tht herring is not s effective s squid t ttrcting snow cr. Nevertheless, some fishermen use herring lone or in comintion with squid nd/or mckerel nd there re times when herring ppers to perform close to or s well s squid so from n economic stndpoint greter use of herring my hold some merit for the region. Herring nd mckerel re commonly used in the snow cr fishery in the Gulf of St. Lwrence where lrger conicl trps (. m vs.. m) re utilized nd lrge quntities (e.g., up to kg) of herring nd/or mckerel re used to it individul trps.

6 A it comprison study in Newfoundlnd nd CSAR P- The price of herring nd squid cn vry from yer-to-yer nd within fishing seson. When this study ws initited in erly July of 9 squid ws. the cost of herring ($./l vs. $./l). Fishing enterprises need to optimize their fishing opertions in order to mke them s profitle s possile prticulrly in yers when the price of snow cr is low (e.g., $./l in 9) nd reduction in the cost of it is one wy to improve upon the ottom line. Lrge quntities of herring re eing cptured loclly, however the potentil economic enefits of using herring s it in the snow cr fishery hve not een previously studied. In the current study, cpture rtes of snow cr were compred on snow cr fishing grounds in Conception By in July y utilizing four it configurtions of squid nd/or herring. The it configurtions tested were compred mong four commercil fleets, in which ll trps in fleet were ited eqully, nd from science fleet in which ll it configurtions were rndomly represented. MATERIALS AND METHODS The trditionl conicl snow cr trp utilized in the Newfoundlnd nd Lrdor fishery ws used in this study (i.e.,. m ottom dimeter). All trps were fitted with mm ( ½") stretched mesh nd single top mounted plstic entrnce cone (Fig. ). All trps were fished with lrge ( cm. cm; " ") polyethylene it protection gs (Fig. ) which were hung from the centre of the trp y ttchment to the entrnce cone. Bit protection gs reduce scvenging y se lice (mphipods). Use of it protection is common prctice during the execution of this fishery. Herring it requires the use of it protection due to its soft nture nd inility to sty on skivers while squid it is often hung freely on skivers ut my lso e plced in it protection devices (mesh gs or perforted tus). To this end it ws decided tht ll it used in this study would e plced in protective gs to mintin consistency mong the it configurtions tested. The herring it used in this study ws cptured loclly in the current yer nd fst frozen to mintin freshness. The squid it ws imported from the United Sttes ut ws lso cptured nd fst frozen in the current yer. Bit ws prtilly thwed on dily sis to llow seprtion from frozen - kg locks prior to eing plced in the it gs.

7 A it comprison study in Newfoundlnd nd CSAR P- Four it tretments (it configurtions) of squid nd/or herring were used to compre the ctch rtes of snow cr. Tretment I ws the quntity of squid typiclly used to it trp. Tretments II nd III comprised herring s quntittive nd monetry vrints of Tretment I nd Tretment IV ws comintion of squid nd herring. When squid is the only it used, fishermen typiclly use six squid to it trp (Alex Dy, High Tide Enterprises, pers. comm.). It ws discovered from severl replicte weight (± g) mesurements tht six squid weigh n verge of.9 kg ( ls). The first vrint of Tretment I ws n equl weight of herring (.9 kg) which ws found to consist of three fish. The second vrint ws quntity of herring tht ws pproximtely the monetry vlue of.9 kg of squid. The price of herring nd squid cn vry from yer-to-yer nd within fishing seson. When this study ws initited squid ws. the cost of herring ($./l vs. $./l) therefore Tretment III consisted of pproximtely. kg ( l) of herring which ws found to consist of seven fish. The finl vrint ws n pproximtion of : rtio of squid nd herring to weight of pproximtely.9 kg which consisted of two herring nd three squid. Overll the four it tretments my e summrized s follows: Tretment I: Tretment II: Tretment III: Tretment IV: ls squid (.9 kg), ls herring, ls herring (. kg), nd ls : squid:herring. Ctch rtes of the four it tretments/configurtions were ssessed under simulted commercil conditions y using seprte fleet of trps for ech it tretment (i.e., four commercil fleets). Severl fctors cn influence ctch rtes in ited trps other thn chnge in it configurtion or quntity of it. For exmple, differences in undnce of snow cr within the effective trp re of n individul trp or fleet of trps my influence ctch rtes. A fleet of trps ited with herring my perform etter thn fleet of trps ited with squid simply ecuse there ws greter undnce of snow cr in the effective trp re of the fleet of herring trps. However, cceptle trends in reltive cpture performnce mong it tretments my e expected when lrge nd comprle numer of sets re crried out with ech it tretment, prticulrly when they re crried out on the sme fishing grounds.

8 A it comprison study in Newfoundlnd nd CSAR P- One wy to del with locl differences in undnce of snow cr nd its effect on ctch rtes is to rndomly distriute replictes of ech it tretment within fleet of trps. In the current study fifth fleet, here referred to s the science fleet, ws used to test for differences in the ctch rtes mong the four it tretments. Five replictes of ech of the four it tretments were rndomly distriuted mong trps in the science fleet. Once the rndom distriution of it tretments ws determined for the science fleet it ws not chnged throughout the course of the study. Studies in the Newfoundlnd nd Lrdor region suggest the effective fishing rdius of snow cr trp is pproximtely 7 m ( ftm; E. Dwe, DFO, pers. comm.). In the current study, the distnce etween trps within fleet ws set t m ( ftm) in n effort to remove the it influence from one trp to nother. Further, this is the trp spcing commonly used in the regions snow cr fishery. All trps in the commercil nd science fleets were ited dily with fresh squid nd/or herring. Bit removed from the trps ws held on ord the vessel until the end of the dys fishing nd discrded - km from the fishing grounds. This study ws conducted on snow cr fishing grounds in Conception By (Fig. nd ) from - July 9. Five fishing res (FA) were ritrrily selected on Dy. The fishing res were seprted y pproximtely. km ( nm). The five fleets (four commercil nd one science) were rndomly set mong the five FA s so tht ech fleet fished on one of the FA s on Dy. The five fleets were rotted mong the five FA s on dily sis so tht ech FA ws sujected to ll five fleets nd hence ll four it tretments over five-dy rottion. During ech five-dy rottion the fleets were set in north to south orienttion (Fig. nd ). This fivedy rottion of fleets ws to e repeted three times mong the initil five FA s for totl of fishing dys for ech of the five fleets nd three sets per FA for ech tretment/fleet. However, fter five dys of fishing three of the FA s were moved due to high ctch rtes of soft-shell cr. Specificlly, FA s,, nd (Fig. ) were moved to FA s, 7, nd, respectively, for the two remining five-dy rottions (Fig. ). Sok times were pproximtely hours in durtion except on one occsion during the second rottion when ll five fleets experienced sok time of

9 A it comprison study in Newfoundlnd nd CSAR P- pproximtely 7 hours. Herefter, the three five-dy fleet rottions will e referred to s weeks,, nd nd the four it tretments will e referred to s it configurtions. The current fishing pln, which consisted of rotting the five fleets mong closely spced FA s, ws modelled fter typicl fishing prctices. When fishing within reltively limited FA, fishermen my redeploy fleet end over end or to the left or right of the previous deployment. Aprt from single fleet rottion on Dy of Week, when the fleets were moved end over end of the previous deployment within FA (Figure ), ll remining fleet rottions were deployed pproximtely m to the est of the previous deployment within given FA (Figure nd ). The reserch pltform used during this study ws the 9. m (') CFV Islnd Voyger. Although the snow cr fishery is prosecuted y smller vessels (<') on the fishing grounds utilized during this study, lrger reserch pltform (vessel) ws deemed necessry to provide dequte spce for dt collection nd to limit downtime due to inclement wether. One of two representtives of the Conception By Under ' Cr Committee ccompnied the reserch tem throughout the study. Bottom temperture ws recorded dily t two loctions within the study re y ttching temperture dt logger (VEMCO ) to one of the trps within fleet. Opertionl temperture rnge of the dt loggers ws -. to. ºC, resolution ws. to. ºC, nd ccurcy ws ±. to ±. ºC. All temperture dt loggers used in this study re clirted nnully for ccurcy. Bottom depth t ech set loction ws recorded using the fishing vessel s echosounder. Individul trp ctches of snow cr were ssessed for four ctegories: ) legl size hrd-shell mles ( 9 mm crpce width); ) legl size soft-shell mles; ) sulegl size mles; nd ) femles. The count nd totl weight (± g) per trp ws recorded for ech snow cr ctegory. All snow cr cptured during this study were immeditely returned to the ocen within the FA of cpture. Incidentl yctch ws identified to gener nd counted for ech fleet of trps. Snow cr ctch per unit effort (CPUE; kg/trp) nd percent contriution of legl sized soft-shell nd sulegl size mles were compred using nlysis of vrince (ANOVA). Proportionl dt were rcsine squre root trnsformed nd CPUE dt were log (n+) trnsformed to improve

10 A it comprison study in Newfoundlnd nd CSAR P- normlity nd equlity of vrinces. Sttisticl procedures were conducted using SPSS 7..7 (SPSS ). RESULTS During pproximtely three weeks of fishing (- July) totl of 7 fleets ( trps/fleet) were successfully set nd huled (i.e., commercil type fleets nd science fleets). The mjority (9%) of the fleets were left to fish overnight with sok times rnging from. to. hr (men,. hr). During the second week of the study, five fleets (i.e., four commercil nd one science) fished for three nights with sok times rnging from 7. to 7. hr (men, 7.9 hr). Within the study re depths fished rnged from to 9 m (men, m) (79 to 7 ftm; men, 9.9 ftm) (Tle ). Bottom tempertures were suzero throughout the course of the study rnging from -. C to -. C. Trp sturtion ws not oserved during hul-ck reducing the likelihood of escpement of lrge cr through the entrnce cone nd selectivity of smller cr. Bit qulity ws high for oth herring nd squid fter n overnight set which my e ttriuted to the suzero ottom wter tempertures on the fishing grounds. Fishermen prticipting in the study indicted tht the qulity ws sufficient to merit reuse in the commercil fishery. Nevertheless, s ws outlined ove, in the current study ll trps were ited with fresh it dily. Percent contriution of legl size soft-shell snow cr to the totl ctch weight in ll it configurtions comined rnged from % in FA s nd to 79% in FA (Tle ). Legl size soft-shell cr dominted the ctches (>%) t FA s,, nd during the first week of the study (Tle ) which led to shift in fishing effort to FA s, 7, nd for the reminder of the study (Fig. nd ). Fishermen prticipting in the study commented on the high ctivity levels nd overll good condition of the soft-shell snow cr s they were returned to the ocen which my e ttriuted to the quick nd gentle hndling prctices. Percent contriution of sulegl size mle cr to the totl ctch weight in ll it configurtions comined ws highly vrile etween FA s rnging from % t FA to 7% t FA (Tle ). Lowest percent contriutions of sulegl size mle cr to the totl ctch were oserved t FA s,, nd nd 7

11 A it comprison study in Newfoundlnd nd CSAR P- these fishing res lso exhiited the highest percent contriution of legl size soft-shell cr. Severl of the sulegl size mles cptured t FA s,, nd my hve lso een in the softshell stte, however shell condition ws not ssessed for this cr ctegory. Femle snow cr were not cptured t FA s nd nd exhiited the highest percent contriution to the totl ctch weight t FA s nd (Tle ). Fishing res nd lso exhiited the highest percentge of sulegl size mle cr (Tle ). Incidentl yctch ws limited to two gener; Buccinum sp. (whelks) nd Hys sp. (tod crs). Benthic species ssemlges cn provide vlule indictors of the sustrte type within fishing re. In Conception By, tod cr re most commonly encountered in shllower wters (- m) thn snow cr nd pper to prefer grvel nd cole/pele sustrtes ut my lso e cptured on snd nd mud ottom (Miller nd O Keefe 9). Highest ctches of tod cr occurred within FA s nd nd to lesser extent FA s nd nd these four FA s lso exhiited the highest percent contriution of sulegl size snow cr nd femles (Tle ) suggesting mixed ottom type of hrd nd soft sustrtes in these fishing res. Mud ws commonly oserved on trps huled t fishing res,, nd nd soft-shell crs commonly seek ottom res with deep overurden of mud to urrow within for protection from predtors. Men cpture rtes of legl size hrd-shell snow cr vried considerly etween FA s (Fig. nd ) with FA exhiiting the lowest ctch rtes (i.e., < kg/trp) independent of it configurtion nd fleet type (commercil/science), while FA 7 exhiited the highest ctch rtes (i.e., -7. kg/trp) gin, independent of it configurtion nd fleet type. Men cpture rtes of legl size hrd-shell cr within FA 7 were well elow the nnul commercil cpture rtes (i.e., CPUE) in the offshore region of Division L nd mrginlly lower thn the inshore cpture rtes (Tle ). In the current study, ctch rtes within FA did not show evidence of depletion fishing (Fig. 7). Two-wy ANOVAs were performed on the snow cr ctch dt for the ctegories legl size hrd-shell nd sulegl size mle to determine whether the ctch dt within it configurtion could e pooled cross FA s or weeks. Significnce of the interction term in two-wy

12 A it comprison study in Newfoundlnd nd CSAR P- ANOVAs performed on the commercil fleet ctch dt (Tle nd ) precluded n interprettion of the min effects of FA nd week on men CPUE nd susequently one-wy ANOVAs were performed upon ech of the min effects (Tle nd ). Overll, nlyses of the commercil fleet ctch dt indicted there were within it configurtion differences in men CPUE of snow cr etween weeks (Tle ) nd FA s (Tle ) for oth legl size hrdshell nd sulegl size mle cr. Susequently, nlyses of etween it configurtion differences in men CPUE of ech cr ctegory from the commercil fleets hd to e performed seprtely for ech week nd ech FA (Tle 7). When it cme to the within it configurtion nlyses of the effect of FA nd week on the men CPUE in the science fleet the interction term of the two-wy ANOVA s ws significnt in single comprison, the legl size hrd-shell ctegory for trps ited with ls herring (Tle nd 9). For ech of the three remining it configurtions two-wy ANOVA s indicted ctch rtes of legl size hrd-shell cr differed significntly etween FA s ut did not differ significntly etween weeks (Tle ). One-wy ANOVA s to test the effect of FA on ctch rtes in trps ited with ls herring indicted the men CPUE of legl size hrd-shell cr differed significntly etween FA s in Week (F, =., p=.), Week (F, =.9, p=.), nd Week (F, =., p<.). One-wy ANOVA s to test the effect of week on ctch rtes in trps ited with ls herring indicted the men CPUE of legl size hrd-shell cr differed significntly etween weeks in FA (F, =., p=.) nd FA (F, =., p=.9), ut did not differ significntly etween weeks in FA (F, =.9, p=.), FA (F, =., p=.), nd FA 7 (F, =., p=.99). Overll, these nlyses indicted tht n nlysis of etween it configurtion differences in men CPUE of legl size hrd-shell cr hd to e performed seprtely for ech FA ut the ctch dt could e pooled cross weeks in FA s,, nd 7 (Tle ). Two-wy ANOVA s performed on ctch rtes of the sulegl mle ctegory in the science fleet indicted the men CPUE within ech it configurtion did not differ significntly etween weeks ut did differ significntly etween FA s (Tle 9). Susequently, the science fleet ctch dt were pooled y week for the sulegl mle ctegory nd etween it configurtion differences in men CPUE were nlysed seprtely for ech FA (Tle ). 9

13 A it comprison study in Newfoundlnd nd CSAR P- One-wy nlyses of vrince indicted significnt etween it configurtion differences in men CPUE for ech snow cr ctegory cptured in the commercil fleets (Tle 7) ut men CPUE did not differ significntly etween it configurtion for ny of the snow cr ctegories in the science fleet (Tle ). Nevertheless, exmintion of the homogeneous susets (Fig. - ) indicted commercil fleets ited with ls of squid or l : squid:herring comintion exhiit significntly higher ctch rtes of legl size hrd-shell snow cr in five (%) of the comprisons while commercil fleets ited with ls herring were found to exhiit significntly lower ctch rtes thn ll other it configurtions in four (7%) of the comprisons. Exmintion of the homogeneous susets for the ctch rtes of legl size hrd-shell cr (Fig. - ) indicted commercil fleets ited with the l : squid:herring comintion significntly outperformed ll other it configurtions in three of the comprisons, significntly outperformed ls squid in n dditionl two comprisons, nd overll performed s well s or etter thn ls squid in (7%) of the comprisons. Two pounds squid significntly outperformed ll other it configurtions in two comprisons, significntly outperformed the ls : squid:herring comintion in two comprisons, nd performed s well s or etter thn l : squid:herring in (7%) of the comprisons. Commercil fleets ited with ls herring did not significntly out perform ll other it configurtions in ny of the comprisons ut did significntly out perform ls : squid:herring in two (%) of the comprisons nd performed s well s ls : squid:herring in n dditionl seven (7%) of the comprisons. Commercil fleets ited with ls herring performed s well s ls squid in (7%) of the comprisons. Commercil fleets ited with ls of herring significntly outperformed fleets ited with ls of herring in seven (7%) of the comprisons while ls herring significntly outperformed ls herring in only one (7%) of the comprisons. Commercil fleets ited with ls herring performed s well s or significntly etter thn squid in five (%) of the it comprisons while ls herring performed only s well s : squid:herring in eight (%) of the comprisons.

14 A it comprison study in Newfoundlnd nd CSAR P- Overll, results from the commercil fleets demonstrte the importnce of squid s it, the importnce of the quntity of it when herring is used lone, nd suggest slight dvntge in ctch rtes with n equl it comintion of herring nd squid. This is further demonstrted y nlysis of the totl ctch in the commercil fleets over the entire study (Fig. nd ; Tle ). Commercil fleets ited with the : squid:herring comintion performed est on weekly sis (Fig. ; Tle ) nd when the ctches were summed over three weeks (Fig. ; Tle ) the : squid:herring comintion cptured.% more legl size hrd-shell snow cr thn squid lone, % more thn ls herring, nd % more thn ls herring. Although men ctch rtes of snow cr in the science fleet did not differ significntly etween it configurtions (Tle ) nd men ctch rtes of ech it configurtion exhiited dissimilr trends when compred to the commercil fleets in the sme FA s (Fig. -) the totl ctch for ech it configurtion did show the sme generl trends s the totl ctch in the commercil fleets, prticulrly when summed over three weeks (Fig. nd ; Tle ). As in the commercil fleets, trps ited entirely or prtilly with squid performed est overll in the science fleet nd higher quntities of herring resulted in higher totl ctch (Fig. ), however the rnk order of ls squid nd the l : squid:herring comintion ws reversed in the science fleet. Overll, when the ctches in the science fleet were summed over three weeks ls squid cptured.% more legl size hrd-shell cr thn the l : squid:herring comintion,.% more thn ls herring, nd % more thn ls herring (Fig. ; Tle ). Legl size soft-shell snow cr dominted the ctches in FA s,, nd nd comprised % of the totl ctch (kg) in FA (Tle ). In the commercil fleets, ctch rtes of legl size softshell cr differed significntly etween it configurtions t FA nd during Week (Tle 7), however the homogenous susets differed etween FA s (Fig. ). Low ctches of soft-shell cr during weeks nd precluded n nlysis of the influence of it configurtion on ctch rtes of this snow cr ctegory. In the science fleet, ctch rtes of legl size soft-shell cr did not differ significntly etween it configurtions during Week (Tle ; Fig. ). Ultimtely, the results re uncler with regrd to ny reduction in ctch rtes of legl size softshell cr with it tretment.

15 A it comprison study in Newfoundlnd nd CSAR P- A more meningful nlysis of the influence of it configurtion on the ctch of soft-shell cr would e comprison of the percent contriution of soft-shell cr to the totl ctch s persistently high percentges of soft-shell cr cn close fishing re for the seson. Two-wy nlyses of vrince indicted the percent contriution of legl size soft-shell cr to the totl ctch (kg) did not differ significntly etween it configurtions within or etween fleet types (commercil vs. science) during Week when soft-shell cr dominted the ctches t three of the five fishing res or over ll three weeks comined (Tle ; Fig. nd ). Men percent contriution of sulegl size mle snow cr to the totl ctch (kg) ws highly vrile mong fishing res ut exhiited reltively little vriility mong it configurtions (Fig. 7). Men percent contriution of sulegl mles lso exhiited low vriility mong it configurtions when summed cross fishing res (Fig. nd 9). Two-wy nlyses of vrince indicted the percent contriution of sulegl size mles to the totl ctch (kg) did not differ significntly etween it configurtions within or etween fleet types (commercil vs. science) during Week nd or over ll three weeks comined (Tle ). During Week, the percent contriution of sulegl size mles did not differ etween fleet types ut did differ etween it configurtions (Tle ). Post-hoc nlyses of the Week dt indicted the l : squid:herring comintion cptured significntly lower proportion of sulegl mles thn ls herring while ls squid nd ls herring exhiited proportions tht were medil to nd did not differ significntly from either the l : squid:herring it comintion or ls herring. Men ctch rtes of sulegl size mles in commercil fleets differed significntly etween it configurtions in of the within FA comprisons (Tle 7; Fig. -). For of these comprisons ctch rtes of legl size hrd-shell cr lso exhiited significnt differences etween it configurtions (Tle 7), however the homogeneous susets differed mong the two cr ctegories (Fig. - nd -). Nevertheless, nine of the comprisons (%) tht exhiited significnt differences in men ctch rtes etween it configurtions showed similr trends in men ctch rtes mong it configurtions for oth the legl size hrd-shell cr nd sulegl size mle cr. Although men ctch rtes of sulegl size mles did not differ significntly etween it configurtions in the science fleet, men ctch rtes of legl size hrdshell cr nd sulegl size mles exhiited similr trends mong it configurtions in seven of

16 A it comprison study in Newfoundlnd nd CSAR P- the comprisons (i.e., 7%; Fig. - nd -). Overll, these results suggest the ttrctive properties of ech it configurtion ct similrly on legl size hrd-shell nd sulegl size mles. Discussion This study demonstrtes the importnce of squid s it in the snow cr trp fishery, the importnce of the quntity of it when herring is used lone, nd suggests slight dvntge in ctch rtes with it comintion of herring nd squid in commercil fleets. The l : squid:herring comintion nd ls squid it configurtions performed est overll in oth the science nd commercil fleets exhiiting totl ctch over huls of ech it configurtion tht were.-% higher thn ls herring nd -% higher thn ls herring. In the commercil fleets, the l : squid:herring comintion nd ls squid were the only it configurtions to significntly outperform (i.e., significntly higher ctch rtes) ll other it configurtions, which they did in % of the comprisons. Commercil fleets ited with the l : squid:herring comintion significntly outperformed ls squid in % of the comprisons while ls squid significntly outperformed the l : squid:herring comintion in % of the comprisons. Fishermen frequently comment on the high vriility in ctch rtes of snow cr even when the commonly preferred it configurtion (i.e., squid lone) is used. For exmple, fleet of trps set on grounds where previous hul performed poorly my provide cceptle or even higher thn usul ctch rtes for the yer during the following hul. Food vilility nd levels of stition mong cr in loclized re cn influence ctch rtes nd fishermen frequently comment on the disml ctches of snow cr tht occur when it-fish (e.g., cpelin) re in the re. Depth nd sustrte type is known to influence cpture rtes of legl size, sulegl size, nd soft-shell snow cr nd seemingly minor differences in temperture lso pper to drmticlly influence ctch rtes (Andrew Dley, pers. comm.). High cpture rtes of sulegl size snow cr re often ssocited with reltively shllow wter res with mixed (soft nd hrd) sustrte types while soft-shell cr re often ssocited with deep nd vrile

17 A it comprison study in Newfoundlnd nd CSAR P- overurden of soft sustrte which is frequently evident on trps when they re huled. In mny circumstnces, the percent contriution of sulegl size or soft-shell cr cn e reduced y moving fishing ger seemingly minor distnces where pprently differences in hitt type (sustrte, depth, temperture, current velocity, etc) reduce the ctch rtes (i.e., presence) of these unwnted size/shell condition ctegories of snow cr. Accepting the fct tht pprecile vriility in ctch rtes of snow cr with the sme preferred it cn e chieved y moving fishing ger seemingly minor distnces or even on wht ppers to e the sme fishing ground (i.e., sme ltitude nd longitude) mkes investigtions compring the performnce of different its dunting tsk. The current study ttempted to del with this vriility y conducting severl () etween it comprisons with oth commercil nd science fleets in hopes tht t the very lest, common trend would emerge. Fortuntely, common trend did emerge with fleets (commercil) nd trps (science) ited prtilly or entirely with squid performing est with regrd to the cpture of legl size hrd-shell snow cr over huls of ech it configurtion. Given the high numer of huls crried out in this study it is unlikely tht dditionl huls would chnge the overll trend in ctches oserved etween it configurtions. Generlly, ctch rtes (i.e., kg/trp) in the commercil nd science fleets were well elow the nnul verges for the NAFO Division where the study took plce (L) which is ttriuted to the previous fishing pressure nd stge of the moult cycle of snow cr. This study ws conducted lte in the fishing seson when most of the inshore quot for Division L ws cptured nd when soft-shell egin to dominte the ctches, hence fewer legl size hrd-shell cr were expected. At this time, there is no reson to suspect tht the overll trends in the reltive performnce of the it configurtions in commercil nd science fleets would chnge pprecily during the height of the fishing seson. In the current study, ctch rtes of ll three ctegories of mle snow cr (legl size hrd-shell, legl size soft-shell, nd sulegl size mle) differed significntly etween it configurtions in the commercil fleets, while in the science fleet ctch rtes did not differ significntly etween it configurtions. One possile explntion for this my hve to do with effective fishing re of ited trp. The four commercil fleets ech comprised only one of the four it tretments while trps in the science fleet were one of four different it tretments, rndomly distriuted

18 A it comprison study in Newfoundlnd nd CSAR P- within the fleet, nd plced m ( ftm) prt. It is possile tht the distnce etween trps within the science fleet my not hve een gret enough to llevite it influence from one trp to the next, thus ccounting for non-significnt differences in ctch rtes etween trps. Studies in the Gulf of St. Lwrence suggest the effective fishing rdius of snow cr trp my e s gret s 7 m when ited with kg (. l) of Atlntic herring or cod (Gdus morhu) (Brêthes et l. 9) nd trps were ited with. kg of herring in the current study. Although it seems intuitive, it is uncler how or even if the effective fishing rdius of trp set for snow cr is ffected y the quntity or type of it. Another possile explntion for non-significnt differences in ctch rtes etween it configurtions in the science fleet is the numer of trp comprisons within ech it configurtion which ws smll (n = ) for the ANOVA s performed nd cn led to reltively high error component in the nlysis which my preclude significnt differences in ctch rtes. Incresing (i.e., douling) the numer of replictes of ech it configurtion in science fleet would help to llevite this prolem. However, n increse in the length of fleet increses the chnce of smpling from different hitt types which y their intrinsic fetures support different quntities of the snow cr ctegories exmined such tht significnt differences in ctch rtes my e due to differing numers of cr within the effective trp rdius rther thn differences due to it configurtion. Results of this study, demonstrted tht commercil fleets ited with l : squid:herring comintion performed mrginlly etter thn commercil fleets ited with ls squid nd given the lower price for herring provide compelling evidence to promote the use of oth it types in the Newfoundlnd nd Lrdor trp fishery. A previous study indicted the quntity of squid lone cn ffect the cpture rtes of snow cr (Miller 9), therefore greter overll performnce oserved in this study with reduction in squid in the l : squid:herring comintion is ttriuted to the comined ttrctnt qulities of oth it types. When this study ws crried out the price of herring ws $./l nd squid ws $./l. Therefore the cost to it trp with l : squid:herring comintion ws pproximtely $.9 compred to $. for trp ited with ls squid such tht trps ited with l : squid:herring comintion result in svings of $.9 per trp. Snow cr trp effort in NAFO Division L over the pst

19 A it comprison study in Newfoundlnd nd CSAR P- yers ws summrized y Dwe et l. (9) nd is presented herein in Tle. To fcilitte cost enefit nlysis, we ssumed tht ll trps in L were ited with ls of squid over the pst yers nd the present cost svings of $.9/trp when ls of squid ws sustituted with the l : squid:herring comintion. The ssumption tht ll trps re ited with squid lone is likely to e more pplicle to the offshore sector. This cost enefit nlysis indictes verge svings of pproximtely $, in the inshore sector nd $9, in the offshore sector for totl verge svings of $9, for Division L over yers. This is simplified cost enefit nlysis for numer of resons, one of which is the price of herring nd squid which vries within nd etween yers however, herring hs lwys een the less expensive it of the two so this nlysis holds some merit. Expnding this cost enefit nlysis to ll NAFO Divisions for the Newfoundlnd nd Lrdor region (NAFO JKLNOPsPnR) for 7 when totl of.9 million trps were set (Dwe et l. 9) would mount to svings of $. million to the hrvesting sector of the snow cr industry. This would require.9 million ls or, metric tons (t) of herring. According to the ltest Science Advisory Report on the sttus of Newfoundlnd herring stocks (DFO 9) this quntity of herring would e redily ville from loclly cught stocks. In 7, four of the five herring stocks (i.e., White By-Notre Dme By, Bonvist By-Trinity By, St. Mry s By-Plcenti By, nd Fortune By) hd comined totl lndings of, t. A l : squid:herring it comintion in 7 would hve ccounted for % of the lndings for the Newfoundlnd nd Lrdor region. The ove cost enefit nlyses ssume tht ll fishermen in the Newfoundlnd nd Lrdor region use squid lone to it their snow cr trps nd tht they typiclly use ls of squid. Although squid my e the preferred it nd s this study suggests for good reson, fishermen use wide vriety of it configurtions nd configurtions with nd without it protection devices. Alterntive its to squid include herring, mckerel, mle cpelin, cod frmes, nd turot heds used seprtely nd in comintion with or without squid. Squid is usully plced on skiver while the other it types re typiclly plced in it protection devices. We suggest tht efore ny dditionl work is performed to verify the current results on commercil scle tht telephone survey e conducted to determine current it usge prctises nd generl

20 A it comprison study in Newfoundlnd nd CSAR P- opinion towrds the use of : rtio of squid nd herring within the region. The survey would lso provide more ccurte estimte of the cost enefit to the industry y promoting : rtio of squid nd herring s severl fishermen my lredy e using this or similr (squid nd mckerel) it configurtions. Such survey should include dequte representtion of ll vessel clsses in the inshore nd offshore sectors nd in n ttempt to mintin ojectivity should e conducted y n independent rms length orgniztion/institution. Ultimtely, to convince the hrvesting sector of Newfoundlnd nd Lrdors snow cr fishery of the vlidity of chnging from the use of squid lone to : rtio of squid nd herring will require demonstrtion of the enefits t the commercil scle. Fctors to consider when ssessing ctch rtes of the two it configurtions t the commercil scle include the use or non-use of it protection s well s the effects of sok time, ottom temperture, nd sustrte type. When squid is used it is commonly plced on skivers with no protection from scvenging se lice, vrious scvenging species of fish, or snow cr s pot fills, while in the current study ll its were plced in lrge it g. The size of it g used in this study ws sed on the need for one g to hold the mximum quntity of herring tested (. kg) with it gs used in the remining it configurtions stndrdized to this requirement. It is unlikely tht use of one or more smller it protection devices would hve influenced the outcome of this study while plcing squid on skivers my, prticulrly when trps re left to sok for long period of time. In the offshore, trps re usully left to sok for - hours, similr to the current study while in inshore wters trps my sok for -7 hours. These differences my led to differences in the performnce of the different it configurtions with or without it protection. Seemingly minor differences in ottom wter tempertures nd sustrte cn lso led to differences in ctch rtes relted to the levels of ctivity nd undnce of the legl size hrd-shell cr such tht differences in ctch rtes my not e relted to the type of it used ut locl hitt conditions. Due to the high vriility in ctch rtes regrdless of the it configurtion used commercil scle demonstrtion of the vlidity of the use of : rtio of squid nd herring over the use of squid lone will require quntittive nlysis from severl huls similr to the pproch used in the current study. Mny of the underlying effects of the fctors tht cn influence ctch rtes irrespective of it configurtion cn e ddressed y mking ville pproprite logooks to skippers interested in prticipting in further nlysis of the merit of 7

21 A it comprison study in Newfoundlnd nd CSAR P- : rtio of squid nd herring nd y providing rndom group of these hrvesters with reserchers nd/or oservers to collect more detiled oservtions nd dt. ACKNOWLEDGEMENTS This study would not hve seen the light of dy without funding from Newfoundlnd nd Lrdor s Deprtment of Fisheries nd Aquculture (DFA). This study ws conducted through collortion on the prt of the Mrine Institute s Centre for Sustinle Aqutic Resources (CSAR), the provincil Deprtment of Fisheries nd Aquculture, the commercil fishing industry, nd Fisheries nd Ocens Cnd (DFO). We would like to thnk numer of individuls for their ssistnce during this study including Rennie Sullivn, Wyne DeGruchy, Georgin Bishop, Tr Perry, Pul Winger, nd the skipper nd crew of the CFV Islnd Voyger. LITERATURE CITED Archdle, M.V., Ansco, C.P., nd Thr, Y.. Ctches of swimming crs using fish mince in tegs compred to conventionl fish its in collpsile pots. Fish. Res. 9: 9-9. Brêthes, J.C., Bouchrd, R., nd Desrosiers, G. 9. Determintion of the re prospected y ited trp from tgging nd recpture experiment with snow crs (Chionoecetes opilio). J. Northw. Atl. Fish. Sci. : 7-. Dle, T., Siikvuopio, S.I., nd As, K. 7. Development of formulted it for edile cr (Cncer pgurus L.) using y-products from the fisheries nd quculture industry. J. Shellfish Res. : 97-. Dwe, E., Mullowney, D., Stnsury, D., Tylor, D., Hynick, E., Veitch, P., Drew, J., Evns, G., Colourne, E., O Keefe, P., Sknes, K., Finder, D., Sted, R., Mddock Prsons, D., Higdon, P., Pddle, T., Noseworthy, B., nd Kellnd, S. 9. An Assessment of Newfoundlnd nd Lrdor Snow Cr (Chionoecetes opilio) in 7. DFO Cn. Sci. Advis. Sec. Res. Doc. 9/7. iv + p DFO. 9. Assessment of Newfoundlnd Est nd South Cost Herring Stocks to. DFO Cn. Sci. Advis. Sec. Sci. Advis. Rep. /9. Miller, R.J. 9. How mny trps should cr fishermn fish? N. Am. J. Fish. Mng. ; -.

22 A it comprison study in Newfoundlnd nd CSAR P- Miller, R.J. nd O Keefe, P.G. 9. Sesonl nd depth distriution, size, nd molt cycle of the spider crs, Chionoecetes opilio, Hys rneus, nd Hys corcttus in Newfoundlnd By. Cn. Tech. Rep. Fish. Aqut. Sci.. p. SPSS Sttistics for Windows, Rel Chicgo: SPSS Inc. Stoner, A.. Effects of environmentl vriles on fish feeding ecology: implictions for the performnce of ited fishing ger nd stock ssessment. J. Fish Biol. : -7. Wlsh, P.. Use of processed fish offl s it in the Newfoundlnd snow cr (Chionoecetes opilio) fishery. Centre for Sustinle Aqutic Resources, Fisheries nd Mrine Institute of Memoril University of Newfoundlnd nd Lrdor, Cnd. P-, iii + 7p. 9

23 A it comprison study in Newfoundlnd nd CSAR P- Tle. Snow cr ctch summry y fishing re (FA) in Conception By, 9. Percent contriution of legl size hrd-shell, legl size soft-shell, sulegl size mle, nd femles to the totl ctch (kg) of snow cr cross ll fleet configurtion nd it configurtions is shown. Incidentl yctch (numer of individuls) is lso illustrted. Dtes No. of Depth Rnge Legl size hrd-shell Legl size soft-shell Sulegl mles Femles Byctch (No.) FA Fished Huls (m) % % % % Tod Whelk - Jul Jul Jul Jul Jul Jul Jul Jul

24 A it comprison study in Newfoundlnd nd CSAR P- Tle. TAC (t), lndings (t), effort (trp huls), nd CPUE (kg/trp) y yer for Division L inshore nd offshore (Tle, from Dwe et l. 9). Yer TAC Inshore Lndings Inshore Effort Inshore CPUE Inshore TAC Offshore Lndings Offshore Effort Offshore CPUE Offshore ,7,79 7,7.,7 7, 9,. 99 7,7 7,9,7.9 7,,9,.9 997,,9 7,.,7,9 9,. 99 7,,79,9.,7, 9, ,,,.,,77,7,77 7.7,,7 7,.,77 7,9 9,77 9.,,,.7, 7,9 9,9.7,,,9. 9,9,,,7.,77,,7., 9,,,.,,, 7., 9,,,99.,, 7,.,,79,,.9,9,9, 9.,,,,9. 7,,,.,,,79,7.7

25 A it comprison study in Newfoundlnd nd CSAR P- Tle. Summry of two-wy nlyses of vrince (ANOVA s) to test the effect of fishing re (FA) nd week on men CPUE (kg/trp) of legl size hrd-shell snow cr cptured in four it tretments of commercil fleets in Conception By, July 9. Source Type III Sum of Squres df Men Squre F-vlue Proility vlue p ls squid FA <.* Week...7.* FA Week....9* Error.. Totl 9. ls herring FA <.* Week * FA Week <.* Error.7. Totl.9 97 ls herring FA. 7.. <.* Week <.* FA Week..7.7 <.* Error.7. Totl.9 99 ls : squid:herring FA <.* Week...99 <.* FA Week <.* Error.7. Totl. 9 *significntly different t the. proility level

26 A it comprison study in Newfoundlnd nd CSAR P- Tle. Summry of two-wy nlyses of vrince (ANOVA s) to test the effect of fishing re (FA) nd week on men CPUE (kg/trp) of sulegl size mle snow cr cptured in four it tretments of commercil fleets in Conception By, July 9. Bit configurtion Source Type III Sum of Squres df Men Squre F-vlue Proility vlue p ls squid FA. 7.. <.* Week...9.* FA Week.. 7. <.* Error.. Totl. ls herring FA <.* Week... <.* FA Week...9 <.* Error..9 Totl.9 97 ls herring FA <.* Week...7.* FA Week...7. Error.. Totl. 99 ls : squid:herring FA <.* Week FA Week...9.* Error.7. Totl. 9 *significntly different t the. proility level

27 A it comprison study in Newfoundlnd nd CSAR P- Tle. Summry of one-wy nlyses of vrince (ANOVA s) to test the effect of week on men CPUE (kg/trp) within FA nd it configurtion for two ctegories of snow cr cptured in commercil fleets in five fishing res (FA; see Figures nd ) in Conception By, July 9. Legl size hrd-shell Sulegl size mle Bit configurtion FA F d.f. p F d.f. p ls squid.,7.*.,7.*.,7.9.,7.*.,.*.,.* 7.9,.9.7, <.*.9,..97,.7 ls herring.,7.9.79,7.9.,.9.7, <.*.7,.., <.* 7.9,7.* 7.9,7 <.*.7,7 <.*.,7.* ls herring 9.9,7 <.*.7,7.* 7., <.*.9,..7,.77.7,.7 7.7,.*.,.7.99,..,.7 ls : squid:herring.97,7..,7.*.7,7 <.*.9,7.*.,.79.9, ,7..77,7.9 7.,7.9*.,7.9 *significntly different t the. proility level

28 A it comprison study in Newfoundlnd nd CSAR P- Tle. Summry of one-wy nlyses of vrince (ANOVA s) to test the effect of fishing re on men CPUE (kg/trp) within weeks - nd it configurtion for two ctegories of snow cr cptured in commercil fleets in five fishing res (see Figures nd ) in Conception By, July 9. Legl size hrd-shell Sulegl size mle Bit configurtion Week F d.f. p F d.f. p ls squid.9,9 <.*.,9 <.*.7,9 <.*.9,9 <.*.9,9 <.*.,9 <.* ls herring.9,9 <.* 7.9,9 <.*.7,9 <.*.,9.7.7,9 <.*.,9 <.* ls herring.,9.*.9,9 <.*.,9 <.*.79,9.*.7,9 <.*.,9. ls : squid:herring 7.7,9 <.*.,9 <.* 9.,9 <.*.7,9.*.,9 <.*.9,9.* *significntly different t the. proility level

29 A it comprison study in Newfoundlnd nd CSAR P- Tle 7. Summry of one-wy nlyses of vrince (ANOVA s) to test the effect of it configurtion on men CPUE (kg/trp) of three ctegories of snow cr cptured in commercil fleets within five fishing res (see Figures nd ) in Conception By, July 9. See Figures - (legl size hrd-shell), (legl size soft-shell) nd - (sulegl size mle) for corresponding homogeneous su-sets. Legl size hrd-shell Legl size soft-shell Sulegl size mle Week FA F d.f. p F d.f. p F d.f. p.,7.*.,7. 7.,7 <.* 7.7,7 <.*.,7 <.*.,7. 9.,7 <.*.,7.7.97,7.*.,7 <.*.,7 <.* 9.,7 <.*.,7 <.*.,7.77.9,7 <.* 7.9,7 <.*.,7 <.*.,7.*.,7..97,7 <.*., ,7 <.*.,7.* 9.7,7 <.*.9,7.*.,7..,7.9.,7.* 7.,7 <.*.9,7.*.7,7 <.* 7 7.,7 <.*.,7 <.*.,7.9 7.,7 <.* *significntly different t the. proility level

30 A it comprison study in Newfoundlnd nd CSAR P- Tle. Summry of two-wy nlyses of vrince (ANOVA s) to test the effect of fishing re (FA) nd week on men CPUE (kg/trp) of legl size hrd-shell snow cr in four it configurtions of science fleet in Conception By, July 9. Bit configurtion Source Type III Sum of Squres df Men Squre F-vlue Proility vlue p ls squid FA <.* Week...7. FA Week.... Error.99. Totl.7 7 ls herring FA <.* Week...9. FA Week.... Error.7. Totl. 7 ls herring FA <.* Week FA Week * Error.9. Totl ls : squid:herring FA <.* Week FA Week.9... Error.9 9. Totl. 7 *significntly different t the. proility level 7

31 A it comprison study in Newfoundlnd nd CSAR P- Tle 9. Summry of two-wy nlyses of vrince (ANOVA s) to test the effect of fishing re (FA) nd week on men CPUE (kg/trp) of sulegl snow cr in four it configurtions of science fleet in Conception By, July 9. Bit configurtion Source Type III Sum of Squres df Men Squre F-vlue Proility vlue p ls squid FA Week FA Week Error.. Totl. 7 ls herring FA <.* Week FA Week....9 Error.. Totl.9 7 ls herring FA <.* Week.... FA Week.9... Error.9. Totl.7 7 ls : squid:herring FA. 7...* Week FA Week Error. 9.7 Totl.9 7 *significntly different t the. proility level

32 A it comprison study in Newfoundlnd nd CSAR P- Tle. Summry of one-wy nlyses of vrince (ANOVA s) to test the effect of it configurtion on men CPUE (kg/trp) of three ctegories of snow cr in science fleets within five fishing res (see Figures nd ) in Conception By, July 9. See text for justifiction for pooling the dt. Legl size hrd-shell Legl size soft-shell Sulegl size mle Week FA F d.f. p F d.f. p F d.f. p.,..,..9,.7.,.9.,.7.,..9,..,.7.,..,..,.9.,.7.,..,.77.,.7.,.9 Pooled Dt Sulegl mles F d.f. p Week -.9,..9,. Week -.7,. Week -.,..,.79 Week - 7.,.7.,.7 Week -.,.7 9

33 A it comprison study in Newfoundlnd nd CSAR P- Tle. Weekly summry of the ctch (kg) of snow cr in commercil fleets y it configurtion, ody size, nd shell condition. Weekly vlues re summed over five commercil fleets of trps (i.e., trps/week). Bit configurtions re presented in rnk order from the lowest to highest totl ctch of legl size hrd-shell cr over the three week period. ls herring ls herring ls squid ls : squid:herring Week Legl size hrd-shell 77 9 Legl size soft-shell Sulegl size mle Totl Week Legl size hrd-shell Legl size soft-shell 7 Sulegl size mle 9 Totl 9 Week Legl size hrd-shell 7 9 Legl size soft-shell Sulegl size mle Totl 9 79 Week - Legl size hrd-shell 7 97,, Legl size soft-shell 9 Sulegl size mle Totl,,,7,

34 A it comprison study in Newfoundlnd nd CSAR P- Tle. Weekly summry of the ctch (kg) of snow cr in science fleets y it configurtion, ody size, nd shell condition. Weekly vlues re summed over five science fleets with five replictes per it configurtion (i.e., trps/week). Bit configurtions re presented in rnk order from the lowest to highest totl ctch of legl size hrd-shell cr over the three week period. ls herring ls herring ls squid ls : squid:herring Week Legl size hrd-shell 9 7 Legl size soft-shell 7 7 Sulegl size mle Totl 7 Week Legl size hrd-shell 9 7 Legl size soft-shell Sulegl size mle Totl Week Legl size hrd-shell Legl size soft-shell 9 Sulegl size mle Totl 7 7 Week - Legl size hrd-shell 9 7 Legl size soft-shell 7 Sulegl size mle 7 Totl

35 A it comprison study in Newfoundlnd nd CSAR P- Tle. Summry of two-wy nlyses of vrince (ANOVA s) to test the effect of fleet type (commercil nd science) nd it configurtion on men percent contriution of legl size softshell snow cr to the totl ctch (kg) during week nd weeks - comined in Conception By, July 9. Source Type III Sum of Squres df Men Squre F-vlue Proility vlue p Week Fleet...9. Bit.9... SC Bit Error. 9.7 Totl Weeks - Fleet.... Bit SC Bit Error.9. Totl. 9

36 A it comprison study in Newfoundlnd nd CSAR P- Tle. Summry of two-wy nlyses of vrince (ANOVA s) to test the effect of fleet type (commercil nd science) nd it configurtion on men percent contriution of sulegl size mle snow cr to the totl ctch (kg) during weeks,, nd nd weeks - comined in Conception By, July 9. Source Type III Sum of Squres df Men Squre F-vlue Proility vlue p Week Fleet Bit SC Bit Error. 9. Totl Week Fleet.... Bit * SC Bit...7. Error. 7. Totl. 9 Week Fleet....9 Bit.... SC Bit Error.7. Totl.7 9 Weeks - Fleet Bit SC Bit.9... Error 7..9 Totl *significntly different t the. proility level

37 A it comprison study in Newfoundlnd nd CSAR P- Tle. Summry of the trp effort nd potentil svings y switching from ls squid to l : squid:herring comintion in the inshore nd offshore snow cr fishing sectors of NAFO Division L from Bit cost is sed on $. / l for herring nd $. / l for squid. Trp effort dt from Dwe et l (7). Inshore Offshore Bit cost Potentil Bit cost Potentil Yer Effort squid : Svings Effort squid : Svings 99 7,7, 9,, 9,,79,7,7 99,7,, 9,, 9,7,, 997 7,, 7,,9 9,,,7,9,9 99,9 77,,99 7,7 9,,,, 9,9 999, 7, 9,,,7,77,,,7, 7,7 7,,99 7,9 9, 9,77,9,,9,9, 7, 7,9, 9,9,,9 7,9 7,79,9 77,, 7,,,7,, 99, 9,,7,9, 7,97,7,,,,7,,,7,,7,7 79,7,,,99,7,9,9,77 7, 7, 99,9 7, 9,7,,,77,,, 7,,, 9,7,,,9,9,,7,7 9, 7, 7,,,,79,7,,,, 7, Avg.,7 $799,99 $9,99 $9,97,7,7 $,9, $97, $,7

38 A it comprison study in Newfoundlnd nd CSAR P- Figure. Trditionl. m conicl trps utilized in the Newfoundlnd nd Lrdor snow cr fishery.

39 A it comprison study in Newfoundlnd nd CSAR P- Figure. A "L x "D it protection g illustrting the loction of grommets nd skivers for ttching to trp.

40 A it comprison study in Newfoundlnd nd CSAR P- Figure. Mp of study loction in Conception By showing fishing res - with fleet loctions for week, July -9, 9. 7

41 A it comprison study in Newfoundlnd nd CSAR P- Figure. Mp of study loction in Conception By showing fishing res,, nd - with fleet loctions for weeks nd, July 9-, 9.