The effects of management

changes on the Catches of two Deep-sea Fishing Clubs in

Central Queensland

John Platten

Capricorn Bunker Consulting 2/17 Bernard Street Rockhampton Qld 4701

Bill Sawynok

Infofish Services PO Box 9793 Frenchville Qld 4701

Published April 2006

Front and Back Cover photographs supplied by Charles Hartridge and John Platten.

Information in this publication is provided as general advice only. For application to specific circumstances, professional advice should be sought.

Infofish Services have taken all steps to ensure the information contained in this publication is accurate at the time of publication. Readers should ensure that they make the appropriate enquiries to determine whether new information is available on a particular subject matter.

© Infofish Services and Capricorn Bunker Consulting All rights reserved. No part of this publication may be reprinted, reproduced, stored in a retrieval system or transmitted, in any form or by any means, without prior permission from Infofish Services.

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Table of Contents

1. Acknowledgements ...........................................................................................................................5 2. About CapReef.......................................................................................................................................6 3. Fish Species .............................................................................................................................................7 4. Summary....................................................................................................................................................8 5. Introduction .........................................................................................................................................10 6. Section 1 – Characteristics of the Club Fisheries....................................................11 6.1 Description of Club Fisheries .................................................................... 11

6.2 Catch Characteristics................................................................................ 13

6.3 Locations Fished ....................................................................................... 15

6.4 Overall Characteristics ............................................................................. 17

7. Section 2 – Club Catch Trends ...............................................................................................17 7.1 Trends in the Number of Fish Caught....................................................... 17

7.2 Trends in the Size of Fish Caught............................................................. 26

8. Section 3 – Influence of Changes in Regulations on Catch ............................28 8.1 Changes in Regulations ............................................................................ 28

8.2 Effect of Bag Limits .................................................................................. 31

8.3 Effects of Changes in Legal Lengths of Fish ............................................. 34

8.4 Effects of Changes in Zoning.................................................................... 35

8.5 Effects of Seasonal Closures .................................................................... 35

8.6 Overall Effects of Management Changes .................................................. 36

9. References.............................................................................................................................................38

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List of Figures Figure 1: (Top) Redthroat Emperor make up over 50% of the catch of both clubs (Middle) Red

Emperor and Saddletail Snapper are important target species for Apex (Bottom) A catch of mixed reef fish (John Platten photos) 12

Figure 2: Percentage contribution to the catch of Yaralla of three species each month in the years 2000 to 2005 14

Figure 3: The average total catch (no. of fish) per trip in each month of Yaralla between 1997 and 2005 15

Figure 4: Maps showing areas fished by Apex (top) and Yaralla (bottom) 16 Figure 5: Median catch rates (fish/person/day) of Yaralla from 1976 to 2005. Vertical bars are drawn

between the 25th and 75th percentiles catch rates 19 Figure 6: Percentage of trips of Yaralla that caught an average of 0-5, 5.1-10, 10.1-15 etc

fish/person for the decades 1970’s, 1980’s, 1990’s and 2000’s 21 Figure 7: Trends in typical catch rate by decade. Cumulative percentage frequency of the catch (X

axis) from trips shown in figure 8 (histograms) and fitted curves (continuous lines) Y axis shows the mid point of the size ranges of figure 8 - the calculated 50th percentiles as measures of typical catch rate are shown for each decade. Fitted curves are of the form %freq = A/1+exp(-B(Catch-C) where A, B and C are constants. 22

Figure 8: Average catch rate of Apex (fish/person/day) between 1995 and 2005 with vertical lines representing the 95% confidence limits of the mean 23

Figure 9: Average catch rate of Apex (fish/person/day) from the shoals area between 1995 and 2005 with vertical lines representing the 95% confidence limits of the mean 23

Figure 10: Percentage frequency of trips catching an average of 0-1, 1.1-2, 2.1-3 etc fish/person 24 Figure 11: Comparison of catch rates (fish/person/day) between the two clubs 24 Figure 12: The median catch rate (fish/person/trip) and average size (kg) of the catch of Yaralla from

1976 to 2005 27 Figure 13: The average catch (fish/person/day) and the average size (kg) of Apex between 1995 and

2005 27 Figure 14: The Median catch rates (fish/person/day) of Yaralla from 1976 to 2005 and changes in

regulation between 1976 and 2005 30 Figure 15: The average catch rate (fish/person/day) of Apex and changes in regulation between 1995

and 2005 31 Figure 16: The percentage frequency of trips of Apex that averaged 0-1, 1.1-2, 2.1-3 etc. fish per

person 33 Figure 17: The number of trips where the catch of Redthroat Emperor by Apex was <=1, 1.1-2, 2.1-

3 etc 33

List of Tables Table 1: Names of fish species used in this report 7 Table 2: Catch composition (total number of fish) of Yaralla fishing charter vessels within the

Capricorn Bunker Group 13 Table 3: Catch composition of Apex fishing offshore from Yeppoon 14 Table 4: The number of trips to sites within the Capricorn Bunker Group by Yaralla and the current

zoning of these locations 15 Table 5: The number of trips to sites by Apex fishing offshore from Yeppoon and the current zoning

of these locations 17 Table 6: Percentage of trips where the average catch (fish/person/trip) of Yaralla was greater than

30, 40 and 50 20 Table 7: Average catch (fish/person/day) and average size (kg) of fish caught by Apex at the

locations fished 24 Table 8: The percentage of trips where the catch of Yaralla exceeded 20, 30, 40 and 50 fish per

person over four decades 32 Table 9: The number of trips and the percentage of trips where the catch of Redthroat Emperor of

Yaralla exceeded 8 and 16 fish between 1999 and 2004 32

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1. Acknowledgements

CapReef has been funded by the Fitzroy Basin Association as part of its Regional Investment Strategy with funding provided by the Natural Heritage Trust. Initial funding to develop the CapReef program was provided by the Great Barrier Reef Marine Park Authority.

The support of a number of Commonwealth and State Government Departments, research and industry bodies is acknowledged.

The support of fishing groups and local fishing clubs is acknowledged. The authors would like to commend the attention to detail and dedication of the clubs involved and especially those that provided their data for this report, Yaralla Deep Sea Fishing Club and Apex Deep Sea Fishing Club. To maintain the standards of records they have has made our task much simpler and assisted in providing what is a very valuable resource for investigating recreational fishing on the Great Barrier Reef.

Yaralla Deep Sea Fishing Club

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2. About CapReef

CapReef is a community based monitoring program that has been established following a series of management changes to the Great Barrier Reef (GBR).

The purpose of CapReef is to improve community involvement and knowledge in management of the Capricorn part of the Great Barrier Reef ecosystem by monitoring and analysis of local effects of management changes on the GBR ecosystem. In recent years the most significant changes in history have been made to management arrangements of the GBR. Major changes resulted from:

Fisheries (East Coast Trawl) Management Plan 1999 Great Barrier Reef Marine Park Zoning Plan 2003 Great Barrier Reef Coast Marine Park 2004 Fisheries (Coral Reef Fin Fish) Management Plan 2003/04

As part of the consultation processes for the changes in 2004 enforcement and monitoring emerged as significant community concerns. In response Capricorn Sunfish, GBRMPA Local Marine Advisory Committee and other interested groups developed the concept of a community based monitoring approach. CapReef received funding from the Fitzroy Basin Association for 2005/06 and 2006/07. A number of projects were established under CapReef to collect data on the effects of the management changes, particularly on fish and fishers. However, CapReef is considered as an umbrella for data being collected in the Capricorn part of the GBR and is working with a number of research projects also collecting data. Projects to date have focused on:

Coordinating CapReef and providing feedback to the community Measuring changes in catch and effort, relative abundance and size structure

of key fish species Determining changes in fisher participation and fishing patterns resulting from

the new Management Plans. Obtaining information on the movement of key fish species from extended

marine national park and conservation zones in the new Management Plans

CapReef has also provided support for Coral Trout monitoring around the Keppel Islands by James Cook University, collection and identification of larval reef fish by the Central Queensland University and water quality sampling at Rosslyn Bay by the Australian Institute of Marine Science. As part of its program to provide feedback to the community a series of technical reports will be provided dealing with various aspect of the data being collected. This report is the first in that series.

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3. Fish Species

Fish names cause considerable confusion as there are many names that can be applied to the same fish species, even in the same region. The Australian Fish Names Committee has developed a list of standard names. A copy of the Australian Fish Names List is available from the website www.fishnames.com.au. CapReef uses the Standard Name for fish species in all reports.

Table 1: Names of fish species used in this report

Standard Name Local Names Abbreviation Scientific Name

Redthroat Emperor Redthroat, Lipper RTE Lethrinus miniatus

Venus Tuskfish Parrot VT Choerodon venustus

A number of Tuskfish species are referred to collectively as Parrot with the most common locally being Venus Tuskfish

Common Coral Trout Barcheek Coral Trout

Coral Trout CT Plectropomus leopardus Plectropomus maculatus

A number of species are referred to collectively as Coral Trout with the most regularly caught being Common Coral Trout and Barcheek Coral Trout

Red Emperor Red Emperor RE Lutjanus sabae

Saddletail Snapper

Crimson Snapper

Largemouth Nannygai, Red Jew Smallmouth Nannygai, Red Jew

SS Lutjanus malabaricus

Lutjanus erythropterus

These two species are collectively referred to locally as Red Jew

Rosy Snapper Rosy Jobfish RS Pristipomoides filamentosus

Snapper Snapper, Pinkie SN Pagrus auratus

Spanish Mackerel

Spotted Mackerel

Mackerel, Spanish Mackerel Mackerel, Spotted Mackerel

SM Scomberomorus commerson Scomberomorus munroi

Goldspotted Rockcod Longfin Rockcod

Cod, Estuary Cod, Goldspotted Cod Matty Cod, Wirenetting Cod

RC Epinephelus coioides

Epinephelus quoyanus

A large number of species are collectively referred to as Cod with the most common being Goldspotted Rockcod and Longfin Cod but in some areas other Cod species dominate

Barred Javelin Grunter, Javelin BJ Pomadsys kaakan

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4. Summary

An assessment of impact of management changes on the catches of two deep sea fishing Clubs in Central Queensland shows that the effects have been different on each of the clubs. The two clubs are the Yaralla Deep Sea Fishing Club (Yaralla) based in Gladstone and the Apex Deep Sea Fishing Club (Apex) fishing out from Yeppoon. Catch data for Yaralla are available from 1976 to 2005 and for Apex from 1995 to 2005. This time series of catch data provided an opportunity to assess the changes to their catch over that time and to examine the effects of management changes. The clubs fishery characteristics can be summarised as:

Both clubs target demersal reef associated species although both take some pelagic species at times.

Redthroat Emperor is of particular significance to both clubs catches. Over 50% of the fish captured are Redthroat Emperor. Venus Tuskfish are becoming increasingly important to both clubs at around 20% of the catch. Coral Trout are an important but relatively small component of the catch (around 10%).

Both clubs fish from drifting charter boats and tend to fish lines on the bottom rigged with two hooks. Hook sizes are generally larger than 6/0. Natural baits of squid or fish are usually used.

The predominant locations fished are scattered reef and coral rubble in 15 to 30m of water.

The number of fish caught by the two clubs, suggests that after an initial major decline in catch rates from the 70’s to the 80’s, catch rates stabilised. A sharp decline was recorded in the catch rate Yaralla in 2004 following changes to bag limits, size limits and the expansion of no fishing zones. This rate was the lowest recorded over the 29 years where data is available. The decline in the catch rate for Apex was smaller but within the range of previous fluctuations. The catch rates of both clubs improved in 2005 compared to 2004. The average size of fish caught by each Club has been relatively stable over the past decade. While in 2004 the catch rate for Yaralla was the lowest recorded there was a significant increase in the average size of fish. This could indicate that the club is targeting larger fish with the lower bag limits. However there has not been any significant change in the average size of fish caught by Apex. Regulation changes to bag and size limits in 1995 do not appear to have had any significant effect on the catch or catch rates of either club. There is evidence to suggest that the catches of Yaralla could have been influenced by changes to regulations since 2003.

The year following the changes corresponded with the smallest catch and catch rates over the 29 years where data is available.

This change in catch occurred immediately following the introduction of the changes after an extended period where catches were relatively stable.

There is evidence within the catch data that indicates the regulatory changes could have caused the reduction in catch. This can be summarised as:

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1. Between 34% and 60% of trips have exceeded 20 fish per person (the current bag limit) over the decades, while only 2 of the trips over the 29 years of club competition exceeded 60 fish per person (the previous bag limit);

2. By far the majority of trips from 1999 to 2003 exceeded the current bag limit for Redthroat Emperor. In 2003 all trips exceeded this limit.

3. The number of Redthroat Emperor declined sharply in 2004, but the average size increased sharply. This suggests that increased size limits may have influenced catch of this species. This is further supported by the recovery in catch rate in 2005 (as more legal sized fish may have become available).

4. Over 80% of trips prior to 2004 were to locations that have been rezoned. Most of these were to locations now zoned yellow where the gear that can be used has been changed.

The catch rates of the club recovered significantly in 2005. This could be

related to increased availability of Redthroat Emperor above the legal minimum size.

The proportional representation of Venus Tuskfish and Coral Trout has increased while the proportion of Redthroat Emperor has decreased. This could reflect a response to changes in bag limits.

There is less evidence to suggest that management changes have had a major influence on the catches of Apex. Some trips have achieved the bag limit for Redthroat Emperor and the areas fished have been altered as a result of zoning. Zoning may have influenced the type of fish caught (with less large inter-reef species taken and a greater percentage of Redthroat Emperor). This means that the number of fish caught has increased but the average size of fish has decreased. This analysis suggests that regulation could have influenced catch rates. However, only two years of catch data is available since the regulation changes. There are several issues other than changes in regulation that could have caused such a decrease in catch rates. The information currently available certainly suggests that continued monitoring of the catch of the club should be undertaken. The different changes to regulation cannot be separated to assess which may have had most influence. Rezoning, catch limits or changes in minimum sizes could all have affected catch rates, either separately or in combination. Once further catch data are available it may be possible to investigate this further. For example if recent increases in size limits result in an increase in the number of spawning fish, we might expect an increase in the total number of fish caught, including released fish, over time.

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5. Introduction

Fishing catches can be highly variable. There are a large number of factors that can affect catches ranging from weather influences, gear efficiency, skill of fishers through to the number of fish available. Only by examining a long time series of catch statistics can a trend in catches be separated from year to year variability. Such statistics are rarely available, particularly in recreational fisheries where there are no marketing imperatives to store catch data. There is one notable exception however, fishing clubs that conduct competitions have good reason both to record catch details and report them. Fishing club competitors are motivated both to maximise their catch within the club rules and to carefully record their results. This report describes the catch and fishery characteristics of two of the six known offshore fishing clubs in Central Queensland. Those described seem representative of the other clubs and have readily accessible and continuous catch statistics. However each club fishes in different locations and has different rules so that there is value in examining all that are made available. As other club data becomes available further reports may be possible. This report describes the catch and fishery characteristics of two offshore fishing clubs in Central Queensland. The Yaralla Deep Sea Fishing Club (Yaralla) fishes the Capricorn Bunker Group on the southern Great Barrier Reef using charter fishing boats out of Gladstone. Catch records from the club exist from 1976 to the present day. The second club is the Apex Deep Sea Fishing Club based in Rockhampton. They have fished the Great Barrier Reef offshore from Yeppoon since the 1980’s. Catch records exist for the period 1995 to the present day. To put this information into perspective there are records available from the time when the Great Barrier Reef Marine Park was first established. It dates back to when no bag limits and few reef closures existed. From the time when there were few outboard craft large enough to fish the reef and from when even fewer had echo sounders. Navigation was largely by compass alone, only larger charter boats had radar to assist navigation and satellite navigation systems did not exist. Recreational fishers were permitted and encouraged to sell their excess catch. The catch records have the potential to demonstrate both the impacts of changing fish abundance and the influence of changes in regulation and equipment on catches. Higgs (1993) and Gartside et al. (1999) note that changes in the target species, methods utilised and competition rules can have important impacts on the catch of fishing clubs. The methods and club rules are also recorded for future consideration. This report is divided into three sections. The first describes the characteristics of the clubs operations, their methods and the locations they fish. The second looks at trends in catches over time in terms of the species composition, numbers of fish caught and their size. The third looks at changes in equipment and regulations over time and seeks to examine how this may have influenced catches.

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6. Section 1 – Characteristics of the Club Fisheries

6.1 Description of Club Fisheries Yaralla Deep Sea Fishing Club

The Yaralla Deep Sea Fishing Club has fished the Capricorn Bunker Group since the early 1970’s. Catch records are available from 1976. The club has utilised charter boats operating out of Gladstone over this time. All club trips are held over a weekend. A club trip commences on Friday afternoons when the trip members assemble at the wharf at around 5pm. They provide their own tackle and bait. Most trips have 10 participants although some trips have occurred with fewer fishers. Until 2005, handlines only were permitted, these were typically rigged with two hooks (although not universally). Bait consists of either squid or fish baits. Often the bait brought by the fishers is supplemented by cutting up small and undesirable species (particularly iodine bream) caught during fishing. Hooks used are of various types but usually larger than size 6/0. A change in rules in 2005 has allowed the use of rods and reels. The charter boat finds anchorage close to the fishing grounds on Friday night and although some fishing is done, this does not count towards the catch recorded. Competition fishing does not commence until Saturday morning, fishing occurs from the drifting boat typically in depths between 15 and 30m. The preferred habitat fished is broken reef and coral rubble. Catch is stored by each fisher and fish are counted and total weight calculated. Species numbers have been recorded since 1997, prior to this only total numbers and weight were recorded. Fishing continues until 4pm when the vessel anchors once again for the night. Fishing resumes Sunday morning and continues until around 11am. Catch is recorded as the total number of fish and total weight of fish for each competitor. Trip totals of species are also now recorded for each person but no records of fish caught and released are maintained. Points are allocated based on the percentage contribution of each competitor to the total catch. There are usually 10 trips each year so that the club records typically provide the catch records of 100 individual fishing trips in a year. The club has always closely followed fishery regulations and no undersized fish or fish in excess of bag limits are recorded. The species targeted are almost universally demersal species. The club members suggest that Redthroat Emperor and Coral Trout are their preferred target species. Other demersal species such as Red Emperor and various Rockcod species are taken relatively frequently and some pelagic species such as Spanish Mackerel are also taken. Pelagic species are seldom specifically targeted however. Figure 1 provides an example of the species targeted. The club subsidises its trips through various fund raising ventures and sponsorships and also has strong social interactions between members. They also may participate in an extended fishing trip, often to the Swains Reefs during the year. However this trip does not count towards their club’s points.

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Figure 1: (Top) Redthroat Emperor make up over 50% of the catch of both clubs (Middle) Red Emperor and Saddletail Snapper are important target species for Apex (Bottom) A catch of mixed reef fish (John

Platten photos)

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Apex Deep Sea Fishing Club The Apex Deep Sea Fishing Club has fished since the early 1980’s, but club records are only available from 1995. The preferred fishing location of the club is to the north of Yeppoon between High Peak Island and the Swains Reefs. Most trips have occurred to the shoals to the north of North West Island (Douglas Shoals, Guthrie Shoals and Karamea Bank). A broader range of species are targeted, most of these are demersal species, particularly Redthroat Emperor and Coral Trout but also included are deeper water inter-reef species such as Saddletail Snapper (Red Jew) and Red Emperor (figure 1). They also set floating lines away from the bottom to catch Mackerel (Spanish Mackerel, and Spotted Mackerel predominantly). There are fewer gear restrictions than Yaralla, (rod and reel and handlines are allowed) but like Yaralla, most fishing is done using two hooks. Bait used is essentially similar to that of Yaralla with the exception that floating lines are baited with pilchards. Trips usually have ten participants, however the length of trips has varied from less than two to over five days depending on the location fished. All fishing is done from drifting boats but the depth range is broader and includes a greater range of inter-reef habitat types. Catch is recorded as the total number of fish and total weight of fish for each competitor but only trip totals were available for analysis. Trip totals of species are also recorded but no records of fish caught and released are maintained. Points are allocated for both the number of fish and the weight (kgs) of the catch. There are usually four or five trips each year so that the club records typically provide the catch records of 40-50 individual fishing trips.

6.2 Catch Characteristics The catch of Yaralla is dominated by Redthroat Emperor and Venus Tuskfish (locally called Parrot). In combination these two species account for 65-80% of fish caught in any year (table 2). Redthroat Emperor accounted for over 50% of the catch in all but one year (table 2). This dominance occurred across the seasons (figure 2), with Redthroat Emperor comprising the dominant catch in all months. Data on individual species was only available from 2000 onwards. Figure 3 shows the average total catch per trip in each month from 1997 to 2005.

Table 2: Catch composition (total number of fish) of Yaralla fishing charter vessels within the Capricorn Bunker Group

Redthroat Emperor Venus Tuskfish Coral Trout Red Emperor Year (% of total fish) (% of total fish) (% of total fish) (% of total fish)

Other Total

1997 508 (49%) 198 (19%) 82 (8%) 20 (2%) 237 (23%) 1045 1998 610 (45%) 269 (20%) 98 (7%) 38 (3%) 340 (25%) 1355 1999 807 (55%) 232 (16%) 99 (7%) 35 (2%) 305 (21%) 1478 2000 916 (59%) 200 (13%) 120 (8%) 21 (1%) 288 (19%) 1545 2001 1173(56%) 297(14%) 137(7%) 41(2%) 454 (22%) 2102 2002 1098 (65%) 153 (9%) 133 (8%) 20 (1%) 275 (16%) 1679 2003 1223 (64%) 297 (16%) 106 (6%) 31 (2%) 250 (13%) 1907 2004 334 (54%) 111 (18%) 80 (13%) 2 (0.3%) 94 (15%) 621 2005 457 (50%) 207 (23%) 107 (12%) 8 (0.9%) 130 (14%) 909

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A larger range of species was taken by Apex (table 3). This reflects the broader range of habitats and depths fished and the greater range of techniques employed. However the Redthroat Emperor still dominates the catch. A greater proportion of the catch consists of deeper water, inter-reef forms such as Saddletail Snapper, Crimson Snapper, Rosy Snapper, Red Emperor and Snapper. There is also a larger proportion of pelagic species (largely Mackerel). Until 2003, Apex very seldom kept or recorded Venus Tuskfish. Since that time this species has become an important component of the catch (around 20% of the catch).

0

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Februa

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ch Redthroat EmperorVenus TuskfishCoral Trout

Figure 2: Percentage contribution to the catch of Yaralla of three species each month in the years 2000 to 2005

Table 3: Catch composition of Apex fishing offshore from Yeppoon

YEAR RTE CT RE VT RS SS RC BJ SM SN Other Fish Total Trips

1995 259 67 65 0 8 85 47 3 3 3 28 568 6

1996 259 59 13 0 2 21 13 0 5 2 26 400 5

1997 137 38 44 0 5 8 27 0 8 1 14 282 5

1998 131 51 23 0 1 0 22 0 9 2 27 266 6

1999 152 35 13 0 6 37 34 4 0 0 27 289 4

2000 236 32 9 0 0 0 26 0 8 0 20 331 6

2001 202 75 22 0 29 119 15 3 0 0 10 475 3

2002 11 1 2 0 2 25 5 8 0 0 1 55 1

2003 357 25 4 0 0 0 13 4 15 0 2 420 3

2004 125 5 7 39 0 0 10 6 2 0 4 198 2

2005 233 19 12 62 0 0 9 13 7 0 20 375 4

Total 2102 407 214 101 53 295 221 41 57 8 179 3659 45

% 57.4 11.1 5.8 2.8 1.4 8.1 6.0 1.1 1.6 0.2 4.9

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0

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Figure 3: The average total catch (no. of fish) per trip in each month of Yaralla between 1997 and

2005

6.3 Locations Fished Yaralla has fished two main locations since 1976; Sykes Reef to Lamont Reef to the south of Heron Island and Broomfield Reef and Wilson Flats to the south east of Northwest Island (figure 4, table 4). These sites are now zoned as Conservation Park (yellow zone). In the past the club has fished a number of locations prior to their closure to fishing in 1980 (One Tree Island, Wreck Island, Tryon Island and Llewellyn Reef). These are now zoned scientific, preservation (pink) and marine national park (green) respectively. Apex has predominantly fished the shoals region (figure 4, table 5) (Douglas Shoals, Guthrie Shoals and Karamea Bank) (largely zoned dark blue). The location fished wide offshore from High Peak Island (figure 4) is now zoned green (marine national park). This club has also fished the furthest from port (at the Swains Reefs). Both clubs have fished the Broomfield Reef region and the Douglas Shoals area. Apex has fished a broader range of depths and habitats (as reflected in their catch composition) while Yaralla has fished relatively similar habitats on most trips, although some deeper areas have been fished on some occasions.

Table 4: Number of trips to sites since 1976 to sites within the Capricorn Bunker Group by Yaralla and the current zoning of these locations (trips to green and pink zones were prior to their closure to

fishing)

Location Change in Zoning Current Zoning No of trips

Sykes/ One Tree/Lamont Rezoned 2004 Yellow 134

Broomfield/Wilson flats Rezoned 2004 Yellow 53

Douglas Guthrie Shoals Blue 28

Fitzroy Reef Blue 4

Masthead Island Rezoned 2004 Yellow 4

Wreck Island Rezoned 1980 Pink 6

Tryon Island Rezoned 1980 Green 1

Llewellyn Reef Rezoned 1980 Green 6

One Tree Reef Rezoned 1980 Scientific research 54

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Location Current Zoning No of trips

Sykes/ One Tree/Lamont Yellow 134

Broomfield/Wilson flats Yellow 53

Douglas Guthrie Shoals Blue 28

Fitzroy Reef Blue 4

Masthead Island Yellow 4

Wreck Island Pink 6

Tryon Island Green 1

Llewellyn Island Green 6

One Tree Sc research 54

Figure 4: Maps showing areas fished by Apex (top) and Yaralla (bottom)

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Table 5: The number of trips since 1996 to sites by Apex fishing offshore from Yeppoon and the current zoning of these locations (trips to green zones were prior to their closure to fishing)

Location Change in Zoning Current Zoning No of trips

Shoals Blue 31

Offshore from High Peak Island Rezoned 2004 Green 3

Swains Blue 3

Flat Island Blue 2

Wilson Island/Broomfield Rezoned 2004 Yellow 6

6.4 Overall Characteristics Some generalisations can be drawn from the clubs fishery characteristics.

Both clubs target demersal reef associated species although both take some pelagic species at times.

The Redthroat Emperor is of particular significance to the club catches. Over 50% of the fish captured are Redthroat Emperor. Venus Tuskfish is becoming increasingly important to both clubs at around 20% of the catch. Coral Trout are an important but relatively small component of the catch (around 10%).

Both clubs fish from drifting charter boats and tend to fish lines on the bottom rigged with two hooks. Hook sizes are generally larger than 6/0. Natural baits of squid or fish are usually used.

The predominant locations fished are scattered reef and coral rubble in 15-30m of water.

7. Section 2 – Club Catch Trends

7.1 Trends in the Number of Fish Caught There are a large number of factors that can affect catches ranging from weather influences, gear efficiency, skill of fishers through to the number of fish available. The catch data from the clubs extends over four decades; a dataset over this length of time has a number of important values. These include:

It should span across most of the factors that would cause natural variability in catch rates so that a trend independent of this variability should be more evident; and

It occurs across a number of changes in regulation and fishing methods that may have influenced catch rates. The data should be comparable with these and other influences to estimate their impact.

This is provided that the catches are comparable from year to year. It is important to ensure that catch is standardised to account for changes in fishing effort. That is the number of fishers and the hours they have spent fishing has varied from year to year, so that catch rates (catch per unit effort) rather than raw catch data must be used. Care must also be taken to ensure that the influence of variability in individual catch rates is considered. In relatively small samples of catches, the influence of

page 17

abnormally high or low catches can mask important trends. Two methods exist to overcome this effect. One is to consider the percentile contributions to catch and compare the high, medium and low catches from year to year. The second is to combine a number of years together and compare these aggregates. By grouping several years variability should be reduced. Both methods have particular advantages and the best approach is probably to use both methods.

The objectives of this section are to describe:

Trends in individual catches over time, i.e. are individual catches changing; and

Trends in trip catches over the time, i.e. has there been a change in typical trip catches or in the number of highly successful trips.

Methods a) Yaralla Deep Sea Fishing Club Data were standardised for the number of participants and the time in days they spent fishing to show the number of fish per angler per day. Data were analysed to indicate the median, 25th and 75th percentile number of fish caught per angler per trip in each year. The median was chosen to reduce any bias of unusually low or high individual catches and variations in skill between anglers. The 75th percentile was used as an indication of the catch of the most successful and the 25th percentile as indicative of the least successful anglers. Trends in catch rate over time were investigated using the correlation between median catch and time, that is examining the degree to which time can explain trends in median catch. The square of the correlation coefficient (Pearson) was calculated using the routines of Systat 10. Average trip catch rates (Total fish/total no of fishers) were also calculated for all trips. The frequency of catch rates in classes 0-5, 5.1-10, 10.1-15 etc were then calculated for each decade (1970’s, 1980’s, 1990’s and 2000’s). These were then converted to percentage frequencies to standardise for variations in the number of trips. These frequencies were used to investigate the number of trips where large and small catches were made. The percentage frequencies were then converted to cumulative percentage frequencies and a logistic curve fitted to the information for each decade. The suitability of this curve in explaining the data was assessed using a chi-squared test between observed and calculated values. The fitted model was then used to predict the 50th percentile for each decade; that is to predict the typical catch of a trip in each of the decades.

b) Apex Deep Sea Fishing Club

The catch data were also standardised both for the number of fishers and the length of each trip. So that catch rates were recorded as fish per person per day. Note that on some trips part days were fished. Individual catch rates for fishers were not available so that medians and percentiles could not be calculated. As a result average catches were used.

page 18

Trends in catch rate over time were investigated using the correlation between average catch and time, that is examining the degree to which time can explain trends in average catch. The square of the correlation coefficient (Pearson) was calculated using the routines of Systat 10. Data were available from 1995, so that aggregation by decade was not used for this data. However the frequency of catch rates in classes 0-5, 6-10, 11-15 etc were calculated to investigate the distribution of catch rates across trips. Catch rates were also calculated separately for the most frequent location visited (the shoals area). Results a) Yaralla Deep Sea Fishing Club A plot of the median, 25th and 75th percentiles of fish per person per trip shows a slight negative trend in catch rates over the full time period (figure 5). The catch rates from year to year are highly variable and this variability tends to reduce the reliability of any predictions of trends. Time explains only 17% of the variance in catch rates (r2 = 0.1714). Of particularly note was the sharp decline evident in 2004. This was the lowest catch rate observed over the last 29 years. Very high catch rates were reported in 1978 and 1991. On average the difference between the 25th and 75th percentile of catch rates is over 55% of the median value. This demonstrates the high variability of catch rates between the fishers of the club. However, the trends from year to year in the 75th and 25th percentiles follow a similar trend to that of the median (figure 5).

0

5

10

15

20

25

1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005

Fish

/per

son/

day

Figure 5: Median catch rates (fish/person/day) of Yaralla from 1976 to 2005. Vertical bars are drawn between the 25th and 75th percentiles catch rates

The analysis of trip average catch shows that most trips had average catches over 15 fish per person, however there has been a decline in the proportion of trips where average catch was greater than 30 fish per person. In the 1970’s over 30% of trips recorded average catches of over 30 fish per person, while in the 2000’s only 2% of trips had catch rates over this figure (table 6, figure 6). A similar trend can be seen for trips catching greater than 40 and 50 fish (table 6, figure 6).

page 19

The models of cumulative percentage frequency provided a good description of the observed data (Chi-squared tests show a probability between 0.86 and 0.99 that there is no significant difference between observed and calculated values). The models for the decades (figure 7) show that median catch declined from the 1970’s (20.15) to the 2000’s (14.30). Most of the decline occurred from the 1970’s to the 1980’s (20.15 to 15.67), with catches improving in the 1990’s before declining in the 2000’s.

Table 6: Percentage of trips where the average catch (fish/person/trip) of Yaralla was greater than 30, 40 and 50

Decade Over 30 over 40 over 50

1970's 31.0 12.1 6.9

1980's 10.3 4.3 0.0

1990's 23.7 10.2 3.4

2000's 2.1 0.0 0.0

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1970's

0.0

5.0

10.0

15.0

20.0

25.0

30.0

0-5

5.1-10

10.1-15

15.1-20

20.1-25

25.1-30

30.1-35

35.1-40

40.1-45

45.1-50

50.1-55

55.1-60

60.1-65

65.1-70Av. catch (no of fish)

% o

f trip

s

1980's

0.0

5.0

10.0

15.0

20.0

25.0

30.0

0-5

5.1-10

10.1-15

15.1-20

20.1-25

25.1-30

30.1-35

35.1-40

40.1-45

45.1-50

50.1-55

55.1-60

60.1-65

65.1-70

Av. catch (no of fish)

% o

f trip

s

1990's

0.0

5.0

10.0

15.0

20.0

25.0

30.00-5

5.1-10

10.1-15

15.1-20

20.1-25

25.1-30

30.1-35

35.1-40

40.1-45

45.1-50

50.1-55

55.1-60

60.1-65

65.1-70

Av. catch (no of fish)

% o

f trip

s

2000's

0.0

5.0

10.0

15.0

20.0

25.0

30.0

0-5

5.1-10

10.1-15

15.1-20

20.1-25

25.1-30

30.1-35

35.1-40

40.1-45

45.1-50

50.1-55

55.1-60

60.1-65

65.1-70

Av. catch (no of fish)

% o

f trip

s

Figure 6: Percentage of trips of Yaralla that caught an average of 0-5, 5.1-10, 10.1-15 etc fish/person for

the decades 1970’s, 1980’s, 1990’s and 2000’s

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1970's

0.020.040.060.080.0

100.0

2.5 7.5 12.5 17.5 22.5 27.5 32.5 37.5 42.5 47.5 52.5 57.5 62.5 67.5020406080100

1970’s 50th percentile 20.15, chi test p = 0.917

1980's

0.020.040.060.080.0

100.0

2.5 7.5 12.5 17.522.5 27.532.5 37.542.5 47.552.5 57.5 62.5 67.5020406080100

1980’s 50th percentile 15.67, chi test p = 0.992 th percentile 15.67, chi test p = 0.992

1990's

0.020.040.0

60.080.0

100.0

2.5 7.5 12.5 17.5 22.5 27.5 32.5 37.5 42.5 47.5 52.5 57.5 62.5 67.502040

6080100

1990’s 50th percentile 16.57, chi test p = 0.858 1990’s 50th percentile 16.57, chi test p = 0.858

2000's

0.020.0

40.060.0

80.0100.0

2.5 7.5 12.5 17.522.5 27.532.5 37.542.5 47.5 52.557.5 62.567.5020

4060

80100

2000’s 50th percentile 14.30, chi test p = 0.9997 2000’s 50th percentile 14.30, chi test p = 0.9997

Figure 7: Trends in typical catch rate by decade. Cumulative percentage frequency of the catch (X axis) from trips shown in figure 8 (histograms) and fitted curves (continuous lines) Y axis shows the mid point of the size ranges of figure 8 - the calculated 50th percentiles as measures of typical catch rate are shown

for each decade. Fitted curves are of the form %freq = A/1+exp(-B(Catch-C) where A, B and C are constants.

Figure 7: Trends in typical catch rate by decade. Cumulative percentage frequency of the catch (X axis) from trips shown in figure 8 (histograms) and fitted curves (continuous lines) Y axis shows the mid point of the size ranges of figure 8 - the calculated 50th percentiles as measures of typical catch rate are shown

for each decade. Fitted curves are of the form %freq = A/1+exp(-B(Catch-C) where A, B and C are constants.

page 22

b) Apex Deep Sea Fishing Club The plot of average catch from 1995 showed evidence of a slight increase in average catch (figure 8). A similar trend exists in the catch from the shoals area only (figure 9). However the variability between years and the range of locations fished, casts considerable doubt over any firm trend (r2 for trend line between time and catch rate = 0.2128). A much longer time series from similar fishing locations is needed to reach any firm conclusions.

On most trips between four and eight fish were caught per person per day (figure 10). The shoals area produced the best results in terms of the number of fish per trip, followed by the Capricorn Bunker Group, the Swains reefs, High Peak Island, and Flat and Perforated Islands (table 7).

0

1

2

3

4

5

6

7

8

9

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005

fish/

pers

on/d

ay

Figure 8: Average catch rate of Apex (fish/person/day) between 1995 and 2005 with vertical lines representing the 95% confidence limits of the mean

Shoals

0123456789

1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005

Fish

/per

son/

day

Figure 9: Average catch rate of Apex (fish/person/day) from the shoals area between 1995 and 2005 with

vertical lines representing the 95% confidence limits of the mean

page 23

02468

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0-1 1.1-2 2.1-3 3.1-4 4.1-5 5.1-6 6.1-7 7.1-8 8.1-9 9.1-10

10.1-11

11.1-12

12.1-13

16.1-17

23.1-24

Av. catch (no of fish)

% fr

eque

ncy

Figure 10: Percentage frequency of trips catching an average of 0-1, 1.1-2, 2.1-3 etc fish/person

Table 7: Average catch (fish/person/day) and average size (kg) of fish caught by Apex at the locations fished

Location Av Catch Av size (kg)

Shoals 4.05 1.75

Cap Bunker 3.88 1.58

High Peak 1.95 3.32

Swains 2.62 2.40

Flat/Perforated 1.34 2.77

0

2

4

6

8

10

12

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005

Fish

/per

son/

day

Club XYaralla

Figure 11: Comparison of catch rates (fish/person/day) between the two clubs

page 24

Discussion a) Yaralla Deep Sea Fishing Club The results provide a good picture of the catch trends over the period 1976 to the present. In terms of the number of fish captured several generalisations can be inferred:

Catch is variable from year to year and between fishers; This makes clear trends in catch rates difficult to separate from year to year

variability, however the lowest catch rates have been recorded recently in 2004;

Aggregation of catch statistics by decade should reduce variability and suggests that typical catch on trips initially decreased from the 1970’s to the 1980’s by around 25% but then stabilised during the 1980’s and 1990’s. There is evidence that a further decline may be occurring in the 2000’s; and

There has been a reduction in the largest catches over time and the number of trips where larger than average catches were taken has decreased. The size of catches on “typical” trips has remained relatively stable however.

b) Apex Deep Sea Fishing Club The catches of Apex are also variable even on trips to the same locations. Data are only available over ten years, so that it is difficult to separate year to year variability from any trends in catch rates. However there is some evidence of an upward trend in the number of fish caught. The reasons for changes in catch rates are considered further below, however it is noteworthy that Apex has fished the shoals area and the Capricorn Bunker Group more frequently in recent years. These areas are where the club has averaged a higher catch rate over the years. That is the upward trend in catch rate could be related to the locations fished. It is notable that the catch rate of Apex is smaller than that of the Yaralla club, even when fishing the Capricorn Bunkers (figure 11). However the trends in catch rate over time follows a remarkably similar pattern (figure 11). This suggests that the major influences on catch rate are likely to be similar. When a comparison of the species composition of the catch of the two clubs is made, it can be seen that there are smaller numbers of Redthroat Emperor caught by Apex. This suggests that Yaralla may be more successful in targeting Redthroat Emperor. This could relate to the methods used or the locations and habitats fished. The catch rates by location show that the number of fish caught is not dependent on distance from port. Catch rate at the Swains Reefs (over one hundred nautical miles from port) were lower than those of the shoals area. However the species composition of the catch from the Swains suggests that deep water large species predominated. Redthroat Emperor represented less than 15% of the catch on these trips while Rosy Snapper, Red Emperor, Saddletail Snapper and Crimson Snapper comprised 65% of the catch. This suggests that the lower catch rate at the Swains may be largely related to the habitats fished, rather than other factors. It is also probable that larger fish are actively targeted by the club.

page 25

General Trends The number of fish caught by the two clubs, suggests that after an initial major decline in catch rates from the 70’s to the 80’s, catch rates have stabilised. The major decline in catch rate of Yaralla evident in the last year deserves close examination and is considered in Section 3. To establish a trend in catch rate does not establish reasons for the trend. This is a complex and difficult task, particularly since many factors may act in combination.

The number of fish is only half the story however; to consider the changes over time more fully it is necessary to consider changes in the size of the fish.

7.2 Trends in the Size of Fish Caught Changes in the average size of fish caught over time can be an indicator of changes in fish recruitment or an indicator of over-fishing. In a mixed species fishery, changes in fish size may also indicate a change in species composition and differences in the size of fish between fisheries can reflect differences in fishing methods. Both clubs record the number of fish and the total weight of the catch of each competitor. Unlike fish numbers however, the weight of separate fish species is not recorded. Thus there is data available to determine the average size of all fish but not average size of each species. Methods The average size of fish on each trip (total weight over total number of fish) was determined and trends over time examined for each club. In addition the average size was compared with the average number of fish caught to determine if a correlation between the number of fish and their size existed. Pearson correlations were calculated using the routines of Systat10 statistical software. Results a) Yaralla Deep Sea Fishing Club As with the numbers of fish caught, there is no clear trend in average weight over time (figure 12). Average catch weight is negatively correlated with the number of fish caught (r = -0.46), that is as the number of fish increases, the size of fish decreases. Of particular note is that in 2004, size increased substantially as fish numbers decreased.

page 26

0

5

10

15

20

25

30

35

1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004

no fi

sh

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

kg

no.fishAv.Size

Figure 12: The median catch rate (fish/person/trip) and average size (kg) of the catch of Yaralla from

1976 to 2005

b) Apex Deep Sea Fishing Club The average size of fish has tended to decrease over time (figure 13). Size is once again negatively correlated with fish numbers (r=-0.662). Average size varied with location fished (table 7), the shallower areas (the shoals and the Capricorn Bunkers) had larger numbers of smaller fish, while the deeper areas (Swains, High Peak Island, Flat Island and Perforated Island) had fewer but larger fish. This is reflected in correlations between weight and size by location. When weight is compared with catch numbers by location a strong negative correlation is indicated (r=-0.887). This indicates that locations where the numbers of fish caught were smaller, the fish were larger in size.

Figure 13: The average catch (fish/person/day) and the average size (kg) of Apex between 1995 and

2005

0

1

2

3

4

5

6

7

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005

fish/person/dayaverage size

page 27

Discussion a) Yaralla Deep Sea Fishing Club There is little support in the data for a clear trend in the size of fish caught over time. This finding is hardly surprising given that reef fish have notoriously variable growth rates with growth being variable between years and between individual fish. As fish numbers have increased, size has tended to decrease. This probably reflects changes in recruitment of the most common species (Redthroat Emperor) over time, although without species composition data for the full time period, changes in the species caught (larger numbers of smaller species in some years) cannot be ruled out. The increase in average weight in the last two years corresponding with a rapid decrease in fish numbers follows this trend, but the magnitude of the increase in weight is unusual. This is considered further in Section 3. b) Apex Deep Sea Fishing Club Changes in fish size over time probably reflect changes in the locations fished rather than any indication of decrease in the average size of particular fish species. The locations where fish were smallest have been fished more frequently in the recent past. The differences in average size of fish across the locations reflect the species caught. In the shoals area and the Capricorn Bunkers Redthroat Emperor dominate the catch. In deeper locations, other larger species such as Saddletail Snapper, Crimson Snapper, Red Emperor and Mackerel comprised a larger proportion of the catch. The increase in the proportion of the smaller Venus Tuskfish in the catch will also tend to decrease the average size of fish caught. The size of fish also offers an explanation for the difference in the number of fish caught between the clubs (figure 11). While Yaralla catches more fish (as discussed above), they tend to be smaller. For the locations most directly comparable (the shoals and the Capricorn Bunkers) the average size of fish for Yaralla between 1995 and 2005 was 1.18kg, the average size for Apex was 1.75kg for the shoals and 1.58kg for the Capricorn Bunkers. In both clubs Redthroat Emperor dominate the catch in these locations so it may be that Apex targets larger fish (perhaps using larger hooks).

8. Section 3 – Influence of Changes in Regulations on Catch

8.1 Changes in Regulations The club catch data provide a valuable insight into the changes in catches and the influence of regulations impacting on fishing. There are club records available from the time when the Great Barrier Reef Marine Park was first established (1975). They date back to when no bag limits and few reef closures existed. Recreational fishers were permitted and encouraged to sell their excess catch until 1991. This is in contrast to today where comprehensive bag limits, size limits, seasonal closures and multi-use zoning regulates fishing increasingly closely. Historical catch records can be a valuable tool to investigate the impacts of such changes in regulation.

page 28

It is not possible to describe all the possible causes of changes in catch rates. This means it cannot be definitively established that the cause of changes in catch rates is any particular factor (such as fisheries regulation); however inferences for further investigation are possible. Most major factors such as the time spent fishing and the number of fishers are controlled by the nature of the club records (see Section 2). Others are not controlled. Climate is likely to influence catch rates for instance. The skill level of competitors will vary and the group fishing from year to year does not remain the same, however a core group of fishers have remained active throughout much of the study period. There are controls on the type of gear that can be used but increasingly efficient gear (or experience in using it) could influence results.

This section investigates only the influence of regulation change, other influences such as climatic change will be discussed in a later report. It must also be realised that regulations are designed to achieve sustainability in the fishery and as such may need to decrease the take of fishers. Thus this section makes no value judgment as to whether the changes and their impacts are justifiable. It is designed to provide a basis for future informed debate. The major changes in regulation relate to changes to:

Who may catch fish for sale; The size and numbers of fish that may be taken; and Regulations on where and how fishing may be conducted.

Until 1991 recreational fishers could market catch excess to their requirements through what was then called the local fish board. Reef fish were first regulated separately from other species with the Fisheries Regulation (1995). Prior to this, some minimum size regulation existed but no limits to the number of fish that could be taken by recreational fishers were imposed. In 1995 a set of size and bag limits were established. Both species bag limits and total catch limits were enacted across reef fish species. Ten fish of most reef species were allowed to be caught up to a trip bag limit of 30 fish per person. Those fishing on charter boats over a period greater than one day were allowed twice the normal bag limits. Minimum size limits for a number of commonly caught species were also regulated. For example size limits of 35cm for Redthroat Emperor, 30cm for Venus Tuskfish, 45cm for Red Emperor and 38cm for Coral Trout were established at this time. In 2003 the Coral Reef Finfish Management plan was introduced. This changed both size and bag limits. For example Redthroat Emperor size limits were increased to 38cm and Red Emperor size limits increased to 55cm. Bag limits were also reduced. The total bag limit was reduced to 20 fish per person and the exemption applied to charter boat fishers was removed except for when a trip exceeded 72 hours. Individual bag limits also were reduced. For example limits for Redthroat Emperor fell to eight fish per person, Coral Trout to seven fish, Venus Tuskfish to six fish per person and Red Emperor to five. The management plan also established three, nine day periods of closure to fishing for coral reef fish corresponding to the new moon in October, November and December of each year.

page 29

Some closures to fishing existed before the enactment of the Great Barrier Reef Marine Park Act in 1975, but this Act established a process for multiple use zoning. The first zoning plan was established and enabled in the late 1970’s. Most of these first closures related to reefs associated with coral cays. A new zoning plan was established in 2004. Timelines of catch rates for each of the clubs and the approximate times when changes in regulations were established (figures 14 and 15). The introduction of the Great Barrier Reef Marine Park (and zoning) and the prohibition of recreational fishers marketing fish were followed by initial increases in catch rates. The introduction of bag limits had little impact after 1995, but the later changes to bag limits, size limits, spawning closures and zoning (in 2003) have been followed by falls in catch rates. This latter trend is most marked within Yaralla where the lowest catch rates recorded in 29 years have occurred following the changes in regulations during 2003/04. To demonstrate such associations does not establish cause and effect. There are a large range of factors that could cause an increase or decrease in catch rates. Further analysis is required to examine whether there are other data that can inform if changes in regulation may have been involved in any change in catch rates. To do this, each of the changes is examined separately.

0

5

10

15

20

25

1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005

Fish

/per

son/

day

Ban on marketing of fish by recreational fishers

Marine Park established

First bag limits/size limits

Coral Reef Finfish Management Plan

Rezoning of the GBRMP

Figure 14: The Median catch rates (fish/person/day) of Yaralla from 1976 to 2005 and changes in regulation between 1976 and 2005

page 30

0

1

2

3

4

5

6

7

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005

Fish

/per

son/

day

Fisheries RegulationFirst Bag LimitsSize limits

Coral Finfish Management Plan

Rezoning of the GBRMP

Figure 15: The average catch rate (fish/person/day) of Apex and changes in regulation between 1995 and 2005

8.2 Effect of Bag Limits The changes to bag limits as they impact on the clubs can be summarised as follows. Total catch limits were first introduced in 1995, the total catch limit set at this time was 30 fish per person, for fishers on extended fishing tours (such as the clubs trips), double this catch limit was allowed (60 fish in total). The catch limit for Redthroat Emperor was set at this time at 10 fish per person, 20 fish on extended trips. The changes in 2003 reduced the bag limit to 20 fish per person and changed the conditions such that the double bag limit only applies from the start of the third day. The Redthroat Emperor limit has changed to eight fish per person. This means that for Yaralla the overall bag limit on club trips has changed from 60 fish to 20, the limits for Redthroat Emperor from 20 to 8. If catch rates are influenced by bag limits then there should be evidence of catch rates greater than the bag limits prior to their imposition. The catch records of the clubs were examined for such evidence. Both total catch rates and catch rates of the principal catch species (Redthroat Emperor) were examined. The number of trips where the average total catch rate (fish per person) exceeded 20, 30, 40 and 50 fish was determined. The number of trips where the catch of Redthroat Emperor exceeded eight fish per person (current bag limit) and 16 fish per person (twice the current rate) were also calculated. It might also be expected that if bag limits were affecting catches of particular species, then there may be changes to species composition of the catch. It might be expected that the proportion of the most common species might fall and the contribution of others might increase. Evidence of such a change was sought from the proportional contribution of species before and after changes in regulation.

page 31

a) Taralla Deep Sea Fishing Club

The analysis shows that between 34% and 60% of trips have exceeded 20 fish per person (the current bag limit) over the decades, while only 2 of the trips over the 29 years of club competition exceeded 60 fish per person, the previous bag limit (table 8, figure 6).

Table 8: The percentage of trips where the catch of Yaralla exceeded 20, 30, 40 and 50 fish per person over four decades

Decade over 20 over 30 over 40 over 50

1970's 58.6 31.0 12.1 6.9

1980's 43.1 10.3 4.3 0.0

1990's 42.4 23.7 10.2 3.4

2000's 34.0 2.1 0.0 0.0

Table 9: The number of trips and the percentage of trips where the catch of Redthroat Emperor of Yaralla exceeded 8 and 16 fish between 1999 and 2004

1999 2000 2001 2002 2003 2004

>8 4 7 9 8 10 0

% 57.1 87.5 90.0 80.0 100.0 0.0

>16 2 0 0 1 1 0

% 28.6 0.0 0.0 10.0 10.0 0.0

Trips 7 8 10 10 10 9

The majority of trips from 1999 to 2003 exceeded the current bag limit for Redthroat Emperor. The percentage varied from 57% in 1999 to 100% of trips in 2003. No trips recorded catch rates over the bag limit during 2004 or 2005 (table 9). Only two trips recorded greater than twice the current bag limit and only one reached the previous bag limit (20 fish per trip). This information demonstrates that the latest bag limits are likely to be significantly influencing the catch rates of the club but that relatively few trips would have been impacted by the previous bag limits. This fits with the marked decline in catch rates evident since the latest set of bag limits were applied (figure 12). The catch records suggest that by far the largest impact relates to the bag limit on Redthroat Emperor. In most years (where data was available), over 80% of trips exceeded the bag limit. This bag limit is likely to be influencing both the catch composition (by reducing the proportion of Redthroat Emperor) and the overall catch rate. The Venus Tuskfish was the only other species for which catch rates in excess of the current bag limits were attained. This occurred twice in the period from 1999.

The proportional contribution of species to the catch has also changed (table 2). The percentage contribution of Redthroat Emperor has decreased and the contribution of Venus Tuskfish and Coral Trout has increased. This cannot be definitively attributed to the changes in bag limits based on the limited number of years data available but should be monitored further. There may also be a change in the species targeted (and gear used) by the club as a result of regulation change, this also should be monitored.

page 32

b) Apex Deep Sea Fishing Club In contrast to Yaralla, this club seldom reached the 20 fish per person bag limit (2% of trips) (figure 16). A similar trend occurs with the bag limit of Redthroat Emperor with five of 47 trips recording over eight fish per person (figure 17). This suggests that catch rates are less impacted by bag limits in this club. Similar to Yaralla, it is the bag limit on Redthroat Emperor that will have the most influence (figure 17). Since 1995 only one trip achieved greater than the current bag limit for other species (one trip caught Saddletail Snapper and Crimson Snapper at a rate slightly in excess of the current bag limit).

02468

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0-1

1.1-2

2.1-3

3.1-4

4.1-5

5.1-6

6.1-7

7.1-8

8.1-9

9.1-10

10.1-11

11.1-12

12.1-13

16.1-17

23.1-24

Av. catch (no of fish)

% fr

eque

ncy

Figure 16: The percentage frequency of trips of Apex that averaged 0-1, 1.1-2, 2.1-3 etc. fish per person

Red Throat Emperor

0

2

4

6

8

10

12

0 <=1

1.1-2

2.1-3

3.1-4

4.1-5

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10.1-11

11.1-12

12.1-13

13.1-14

14.1-15

15.1-16

Fish per trip

No o

f tri

ps

Figure 17: The number of trips where the catch of Redthroat Emperor by Apex was <=1, 1.1-2, 2.1-3 etc

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It is noteworthy that with the changes in regulation there may be a shift in species composition of the catch. Since the new bag limits were imposed, there has been an increase in the proportion of Venus Tuskfish in the catch of both clubs (but particularly Apex). This may reflect a change in the attitude of anglers to retaining this species as anglers seek alternatives to Redthroat Emperor as bag limits are approached. The factors influencing the selectivity of recreational fishers will form the basis for a separate CapReef report. Since 1999 only two trips occurred where the current bag limit for this species was attained, but this may change over time if anglers decide to switch from targeting Redthroat Emperor once bag limits are approached.

8.3 Effects of Changes in Legal Lengths of Fish If the changes in legal length are influencing catch rates, it would be expected that the average size of fish would increase, with an associated decrease in the number of fish taken after the change was introduced. It may also be that the proportion of some species taken may decrease if the catch was based around fish below the new legal length. a) Yaralla Deep Sea Fishing Club Figure 11 shows that both the number of fish taken decreases and the average weight of fish increases following the changes in regulation in 2003. This is almost certainly influenced by the catch of Redthroat Emperor. Thus the increase in size limit from 35cm to 38cm may be influencing the catch of this species. It is difficult to separate this effect from the influence of bag limits however, since there is a motivation to keep only larger fish if the number of fish able to be kept is likely to be restricted. Discussions with the club suggest that the increase in size limits of Red Emperor has disproportionately decreased the catch of this species. There is evidence to support this in the catch data in that the proportion of Red Emperor taken fell from a relative steady 2% of the catch to 0.3% following the change in size limits. If size limits are the major cause of these reductions in catch, an improvement in catch rates might be expected over time as larger fish enter the fishery. The results from 2005 tend to support this with a recovery in the number of fish taken. A longer time series of data may provide further evidence of this trend. b) Apex Deep Sea Fishing Club The catch statistics of the club show mixed evidence of a response to changes in size limits. There is no sign of an increase in size of fish following the changes in legal lengths in the catch records of this club. However the average size of fish taken by Apex has always been larger than that of Yaralla. This may indicate that changes in legal length have had less impact for this club. The catch rates of Apex, however, follow the same trend as Yaralla, showing an initial decline in catch rate after the introduction of size limits but then a recovery. This would be expected if minimum sizes are increased. The number of and proportional representation of Red Emperor in the catch has not decreased since the changes in size limits.

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8.4 Effects of Changes in Zoning

If zoning changes are impacting on the catch of the clubs, then it would be expected that the clubs visited locations that have changed zoning prior to the change. It would also be expected that the change in zoning would have restricted the fishing capacity of the fishers. a) Yaralla Deep Sea Fishing Club Table 4 shows that by far the majority of trips (around 88%) have been to locations that have changed zoning over time. Most trips have occurred to locations now zoned yellow (66%), although a significant number have also occurred to green zoned areas and scientific zones. Discussions with the club suggest that they consider that the change in zoning to yellow has had a noticeable effect on their catch rates. This is mainly related to the restriction on the number of hooks allowed. Prior to rezoning, most fishers used two hooks, this is now prevented and only one line with one hook is allowed for each angler. This aspect cannot be tested based on the current data and a controlled test of this aspect would be required to distinguish if a reduction in catch rates could be associated with such a change in fishing practice. b) Apex Deep Sea Fishing Club Twenty percent of trips of the club have been to locations that have changed zoning. Some have been to locations now zoned yellow while others were to areas now zoned green. The trips that were conducted to areas offshore from High Peak Island are now no longer possible as this area is now zoned green. The trips to yellow zones are related to trips to the Capricorn bunker Group. It is difficult to estimate the impact that this may have had on catch rates. The trips to the green zoned areas targeted large inter-reef species and it is likely that the proportion of these species in the catch has decreased now that this area can no longer be fished. This is reflected in the catch data through the species composition, the number of fish caught and their average size. The number of fish caught has risen but the size of fish has fallen since trips to this area ceased. This seems likely to be because of the greater number of trips to the shoals area and the reduction of trips to deeper inter-reef areas. On the trips to the Capricorn Bunker Group anglers will no longer be able to use two hooks and will not be able to use a floating line as well as a bottom line. This will have reduced the number of mackerel taken at this location. However the areas now zoned yellow are not amongst those most frequently fished.

8.5 Effects of Seasonal Closures

If seasonal closures were having a negative impact on catch rates it would be expected that the clubs would have regularly fished these times in years prior to their introduction. The closures are timed from one week before to two days after the new moon in October, November and December in each year. The club records were examined determine how many occasions this period coincided with a club trip between 1995 and 2005. Over this time there were 30 periods that

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corresponded to when these closures would have occurred if the regulation had been in place. Of these one was fished by Yaralla and four by Apex. This suggests that the clubs did not specifically set these times for club trips but that they did at times fish them. Thus the closures may not have had a major impact on catches since they were introduced, particularly since very few trips are conducted in December. The time since the closures were introduced is too short to produce any marked positive influence (most reef fish do not become available to the fishery for some years after they are spawned).

8.6 Overall Effects of Management Changes Yaralla Deep Sea Fishing Club There is evidence to support the view that the catches of Yaralla could have been influenced by changes to regulations since 2003.

The year following the changes corresponded with the smallest catch and catch rates over the 29 years where data is available.

This change in catch occurred immediately following the introduction of the changes after an extended period where catches were relatively stable.

There is evidence within the catch data that indicates the regulatory changes could have caused the reduction in catch. This can be summarised as:

5. Between 34% and 60% of trips have exceeded 20 fish per person (the

current bag limit) over the decades, while only 2 of the trips over the 29 years of club competition exceeded 60 fish per person (the previous bag limit);

6. By far the majority of trips from 1999 to 2003 exceeded the current bag limit for Redthroat Emperor. In 2003 all trips exceeded this limit.

7. The number of Redthroat Emperor declined sharply in 2004, but the average size increased sharply. This suggests that increased size limits may have influenced catch of this species.

8. Over 80% of trips of the club prior to 2004 were to locations that have been rezoned. Most of these were to locations now zoned yellow where the gear that can be used has been changed.

The catch rates of the club recovered significantly in 2005. This could be

related to increased availability of Redthroat Emperor above the legal minimum size.

The proportional representation of Venus Tuskfish and Coral Trout has increased while the proportion of Redthroat Emperor has decreased. This could reflect a response to changes in bag limits with increased targeting of alternatives to Redthroat Emperor as bag limits are approached.

This analysis suggests that regulation could have influenced catch rates. Caution must be advised, however, since only one years catch data was available following the changes in regulation. There are a number of issues other than changes in regulation that could have caused such a decrease in catch rates. The information currently available certainly suggests that continued monitoring of the catch of the club should be undertaken. The different changes to regulation cannot be separated to assess which may have had most influence. Rezoning, catch limits or changes in minimum sizes

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could all have affected catch rates, either separately or in combination. Once further catch data are available it may be possible to investigate this further. For example if recent increases in size limits result in an increase in the number of spawning fish, we might expect an increase in the total number of fish caught, including released fish, over time. Apex Deep Sea Fishing Club There is less evidence to suggest that management changes have had a major influence on the catches of Apex. Some trips have achieved the bag limit of Redthroat Emperor and the areas fished have been altered as a result of zoning. Zoning may have influenced the type of fish caught (with less large inter-reef species taken and a greater percentage of Redthroat Emperor). This means that the number of fish caught has risen but the average size of fish has fallen. Changes in zoning to yellow in the Capricorn Bunkers may have reduced the number of Mackerel caught.

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9. References

Gartside, D.F., Harrison B. & Ryan B.L. (1999). An evaluation of the use of fishing club records in the management of marine recreational fisheries: Fisheries Research 41: 47-61

Higgs, J.B. (1993) A descriptive analysis of records of the recreational reef line-fishery on the Great Barrier Reef: Unpublished MSc thesis James Cook University Townsville

Australian Fish Names List available from the website www.fishnames.com.au.

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