Corner Inlet‐Nooramunga Fishery Assessment 2012

Kemp J, Brown L, Bruce T, Bridge N and Conron S

June 2013

Fisheries Victoria Assessment Report Series No. 68

If you would like to receive this Author Contact Details: Dr Jodie Kemp information/publication in an Fisheries Victoria accessible format (such as large Fisheries Management & Science Branch print or audio) please call the PO Box 114, Queenscliff Vic 3223 Customer Service Centre on: Authorised by the Victorian Government, National Relay Service/TTY: 1 Spring Street, Melbourne 133 677, or email Printed by Fisheries Victoria, Queenscliff, [email protected] Victoria Published by the Department of Primary  The State of Victoria, Department of Primary Industries. Industries, 2013. Copies are available from the website: This publication is copyright. No part may be www.dpi.vic.gov.au/fishing reproduced by any process except in accordance with the provisions of the Copyright Act 1968. General disclaimer This publication may be of assistance to you but Preferred way to cite this publication: the State of Victoria and its employees do not Kemp J, Brown L, Bruce T, Bridge N and Conron guarantee that the publication is without flaw of C (2013). Corner Inlet and Nooramunga Fishery any kind or is wholly appropriate for your Assessment 2012. Fisheries Victoria Assessment particular purposes and therefore disclaims all Report Series No. 68. liability for any error, loss or other consequence which may arise from you relying on any ISSN 1329‐7287 information in this publication. ISBN 978‐1‐74326‐481‐2 (Print)

Corner Inlet‐Nooramunga Fishery Assessment 2012 ii Table of Contents

Corner Inlet and Nooramunga fishery assessment summary ...... 1 Types of fisheries ...... 1 Commercial fishery ...... 1 Recreational fishery ...... 1 Management of Fisheries ...... 2 Fishery assessments ...... 2 Corner Inlet Fishery Assessment 2012 ...... 2 Status of the Corner Inlet Fishery ...... 2

Assessment Process ...... 5 This report ...... 5

Stock structure of key species ...... 6

Stock indicators and status key ...... 7

Assessment figures and tables ...... 9

Integrating local Knowledge ...... 27

Overview of assessment data collection methods ...... 32

Description of the Corner Inlet‐Nooramunga commercial fishery ...... 33

Overview of management arrangements ...... 34

Key species’ life‐history information ...... 35

Seagrass in Corner Inlet ...... 38

Acknowledgements ...... 40

References ...... 41

Corner Inlet‐Nooramunga Fishery Assessment 2012

iii

List of figures Figure 1. Map of Corner Inlet and Nooramunga showing commercial fishing zones numbered 1 to 5...... 9 Figure 2. Trends in annual commercial catch (tonnes) and wholesale market value for the Corner Inlet‐Nooramunga fishery...... 9 Figure 3. Trends in annual commercial fishing effort (days) for the Corner Inlet‐Nooramunga fishery...... 10 Figure 4. Trends in annual commercial harvest (tonnes) of key finfish species of the Corner Inlet‐ Nooramunga fishery...... 11 Figure 5. The proportion of key species’ catch harvested from each fishing zone in Corner Inlet‐ Nooramunga. Data is from 2006/07‒2009/10 combined...... 12 Figure 6. Composition of retained and released catch by recreational anglers from telephone survey data (Ryan et al. 2009; Henry and Lyle 2003) for Corner Inlet...... 13 Figure 7. Estimated regional recreational fishing effort from telephone survey data (Henry and Lyle 2003)...... 13 Figure 8. Annual commercial catch (tonnes) and catch rate (kg/shot) of Australian salmon, and effort (shots) targeting Australian salmon and other species in Corner Inlet‐Nooramunga by haul seine from 1978/79 to 2010/11...... 14 Figure 9. Annual commercial catch (tonnes) and catch rate (kg/shot) of flounder (greenback and unspecified), and effort (shots) targeting flounder and other species in Corner Inlet‐ Nooramunga by haul seine from 1978/79 to 2010/11...... 15 Figure 10. Annual commercial catch (tonnes) and catch rate (kg/km‐lift) of gummy shark, and effort (km‐lifts) targeting Australian salmon and other species in Corner Inlet‐Nooramunga by haul seine from 1978/79 to 2010/11...... 16 Figure 11. Annual commercial catch (tonnes) and catch rate (kg/shot) of King George whiting, and effort (shots) targeting King George whiting and other species in Corner Inlet‐Nooramunga by haul seine from 1978/79 to 2010/11...... 17 Figure 12. Length‐frequency distributions of King George whiting harvested by commercial haul seines in Corner Inlet‐Nooramunga from 2006/07 to 2010/11...... 18 Figure 13. Age‐frequency distributions of King George whiting harvested by commercial haul seines in Corner Inlet‐Nooramunga from 2003/04 to 2010/11 (excluding 2005/06−2007/08)...... 19 Figure 14. Annual commercial catch (tonnes) and catch rate (kg/shot) of silver trevally, and effort (shots) targeting silver trevally and other species in Corner Inlet‐Nooramunga by haul seine from 1978/79 to 2010/11...... 20 Figure 15. Annual commercial catch (tonnes) and catch rate (kg/shot) of southern calamari, and effort (shots) targeting southern calamari and other species in Corner Inlet‐Nooramunga by haul seine from 1978/79 to 2010/11...... 21 Figure 16. Annual commercial catch (tonnes) and catch rate (kg/shot) of southern sea garfish, and effort (shots) targeting southern sea garfish and other species in Corner Inlet‐Nooramunga by haul seine from 1978/79 to 2010/11...... 22 Figure 17. Annual commercial catch (tonnes) and catch rate (kg/km‐lift) of rock flathead, and effort (km‐lifts) targeting rock flathead and other species in Corner Inlet‐Nooramunga by mesh net from 1978/79 to 2010/11...... 23 Figure 18. Length‐frequency distributions of rock flathead harvested by commercial mesh nets in Corner Inlet‐Nooramunga from 2006/07 to 2009/10...... 24

Corner Inlet‐Nooramunga Fishery Assessment 2012 iv Figure 19. Cohort strength distributions of rock flathead harvested by commercial mesh nets in Corner Inlet‐Nooramunga from 1996/97 to 2009/10 (excluding 1997/98, 1999/00−2006/07 and 2008/09)...... 25

Corner Inlet‐Nooramunga Fishery Assessment 2012

v List of tables Table 1. Stock status determination using catch rate indicators for key species of the Corner Inlet and Nooramunga fishery...... 8 Table 2. Commercial effort (tonnes) statistics of the main fishing methods used to harvest finfish species in Corner Inlet‐Nooramunga...... 10 Table 3. Commercial catch (tonnes) statistics of key finfish species of the Corner Inlet‐Nooramunga fishery...... 11 Table 4. Summary of length‐frequency distributions of King George whiting and rock flathead commercial catches in Corner Inlet...... 26 Table 5. Summary of age‐frequency distributions of King George whiting and rock flathead commercial catches in Corner Inlet...... 26

Corner Inlet‐Nooramunga Fishery Assessment 2012 vi Corner Inlet and Nooramunga fishery assessment summary

Corner Inlet−Nooramunga is an internationally recognised Ramsar wetland supporting a rich diversity of plants and animals as well as important commercial and recreational fisheries.

Types of fisheries

Commercial fishery

 Haul seines harvest the majority of the commercial catch (71%) in Corner Inlet, followed by mesh nets (also known as gill Corner Inlet mesh net and haul seine operations. Photo nets) (29%); over the past decade there has credit: Lauren Brown been a decline in haul seine effort and mesh net effort has increased. o Haul seines harvest the majority of King George whiting (90%), southern sea garfish (99%), calamari (99%), silver trevally (96%), Australian salmon (91%) and flounder (all species) (91%)

o Mesh nets harvest the majority of rock Corner Inlet and Nooramunga flathead (70%) and gummy shark (82%).  Total commercial harvest of finfish in 2010/11 was 334 tonnes.

o Rock flathead constituted 23%(by weight), King George whiting (16%), southern sea garfish (12%), calamari (10%) silver

trevally (5%), Australian salmon (4%) of the total commercial catch

o The majority of the commercial harvest is from fishing zones 1 and 2 (see map).

Recreational fishery

The most common species retained by recreational fishers in Corner Inlet are sand and yank flathead, King George whiting, Australian salmon, silver trevally and snapper.

Commercial fishing zones 1−5 of the Corner Inlet and Nooramunga fishery.

Corner Inlet‐Nooramunga Fishery Assessment 2012

1 The assessment process for Corner Inlet uses a weight‐of‐evidence approach that assesses available commercial fishery data including trends in catch, effort, CPUE, catch composition, and catch size/age structures. There are currently no recreational‐fishery or fishery‐ independent data collected in Corner Inlet to assess the fishery.

Recreational fishing in Corner Inlet. Photo Credit: Simon Conron

Management of Fisheries Fisheries Victoria is responsible for managing fisheries and fish resources under the provisions of the Fisheries Act 1995 and the Fisheries

Regulations 2009.

National guidelines for ecologically sustainable development (ESD) of fisheries are used to identify environmental, biological, economic, Assessing information about the condition of fish stocks social and governance dimensions for individual and the impacts of fishing for the sustainable management fisheries. of fisheries. These ESD principles underpin the three key strategic goals of Fisheries Victoria:  ‘Securing’ fisheries resources  ‘Sharing’ fisheries resources  ‘Growing’ or developing the value of the resource for the benefit of the community. Fishery assessments Fishery assessments are designed primarily to provide information on the status of fisheries in

Victoria’s bays and inlets to help address the biological sustainability and governance Healthy fish stocks provide for great fishing opportunities. objectives. Photo credit: Peter Macreadie

Corner Inlet Fishery Assessment 2012 Status of the Corner Inlet Fishery A formal assessment of the Corner Inlet Fishery Fishery condition based on monitoring was conducted in Welshpool, Victoria in June of commercial catch rates 2012. The assessment workshop was attended Commercial catch rates of all species assessed by various stakeholders: were stable or increasing suggesting that the fishery is in good condition. The integration of  representatives of the commercial and local knowledge however, suggests there have recreational fishing sectors been changes in fisher behaviour that would  Fisheries Victoria managers, scientists and also result in increasing catch rates; i.e. the compliance officers increase in catch rates for all species assessed  catchment management representatives. may not reflect increases in fish abundance.

Corner Inlet‐Nooramunga Fishery Assessment 2012

2  There has been a reported increase in the effort between fishing zones has been relatively fishing‐time (total time gear was in the stable for the past decade. There was a shift in water; net soak‐time) of commercial mesh mesh net fishing effort from fishing zone 2 to nets. An abundance of crabs once limited zone 1 in the late 1990s‐early 2000s; and this fishing‐time; a decline in crab abundance shift has been maintained over the past decade. has resulted in a reduction in the level of Commercial fishing effort in zones 3−5 is crab predation on the catch, allowing gear to relatively low compared with fishing zones 1 be set for longer. Fishing‐time is reported by and 2. commercial mesh net operators in Corner Inlet and needs to be standardised for when Trends in commercial catch assessing mesh net catch rates as a measure composition of relative abundance. Over the past decade, there has been a decrease in the proportion of southern sea garfish and  Ringing seine net modifications have also leather jackets commercially harvested and an occurred in recent years, including increase in the proportion of rock flathead. All modifications to increase lead‐line weight. other species examined have remained stable Gear modifications are not reported in (King George whiting, southern calamari, silver commercial log‐books, and therefore cannot trevally, Australian salmon, gummy shark, be quantified using available monitoring flounder, skates and rays, yellow‐eye mullet, data. pike and sand flathead).  Seagrass associated species have less protection from fishing gear due to Recreational fishing significant seagrass loss. Workshop participants reported there had been a significant increase in recreational fishing The above factors were reported to be increasing effort in the inlet; that an overflow of anglers gear efficiency and hence increasing effective from the Melbourne metropolitan area was effort. Therefore, trends in CPUE may not be contributing to the increase in effort; and that reflecting trends in relative abundance. This there had been an increase in recreational limits the effectiveness of available monitoring targeting of snapper in recent years. There is data to confidently assess the status of the currently no monitoring data available on fishery i.e. the stable/increasing CPUE observed recreational fishing effort or catch in the inlet. for all species assessed, may not be indicative of stability/increases in relative abundance. The majority of commercial ‐fishers reported that they are unsatisfied with current fishing conditions in Corner Inlet and that they are having to ‘work harder’ to maintain their catch rates. Trends in commercial catch and effort There have been significant increases in the annual catch of rock flathead and southern calamari over the past 30 years and catches have continued to increase over the past decade; these increases in catch are partially market driven. Commercial fishers reported that the abundance of seagrass is dictating the spatial distribution of fishing effort in the inlet; and that areas available to fish were reduced due to sea grass loss. The spatial information collected in commercial log‐books is not at a scale that facilitates assessment of the spatial distribution and localisation of effort within fishing zones. The spatial distribution of haul seine fishing

Corner Inlet‐Nooramunga Fishery Assessment 2012

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Overview of the status of finfish stocks in Corner Inlet Legend Good condition Corner Inlet Fishery Condition – Limited Data ↑ Improving Break down by fishery indicators: ↔ Stable ↓ Commercial catch rates (note: issues in the data are Decreasing described above) Poor condition  Stable or increasing for: Requires close monitoring/attention o Rock flathead, King George whiting, southern Limited data calamari, southern sea garfish, flounder, Australian salmon, silver trevally and gummy shark  Above the long term average for: o Rock flathead, King George whiting, flounder southern calamari and gummy shark  Below the long‐term average for: o Australian salmon, silver trevally, southern sea garfish Recreational catch rates  Limited data Stock structure  Available commercial age and size class within historical range for: o Rock flathead and King George whiting (however, this data is not representative of the whole fishery)  Limited data available for other commercially harvested species  Limited data available for recreationally harvested species Recent spawning success  Limited data for all species Management settings  Maintain current settings Flagged issues  Available commercial fishery –dependent monitoring data is insufficient to assess the status of the fishery. Haul seine gear modifications and increases in the soak‐ time of mesh nets are influencing catch rates. Soak‐time is reported in commercial log‐books and needs to be standardised for when assessing catch rate trends; gear modifications are not reported in commercial log‐books.  There is no monitoring data available on the recreational fishery which was reported to be increasing.  There is a need for fishery‐independent monitoring in Corner Inlet to effectively assess the status of the fishery  Concern for seagrass decline continues  Community education on the fragility of the shallow bank areas of the inlet that are important nursery areas for juvenile fish is required to reduce the damage that boat traffic is having on these vulnerable areas

Corner Inlet‐Nooramunga Fishery Assessment 2012

4 Assessment Process

Fisheries Victoria has developed a process to A formal assessment of the Corner Inlet fishery conduct periodic formal assessments of the in Victoria was conducted by Fisheries Victoria status of key marine and estuarine finfish stocks in June 2012. and the fisheries they support. The assessment workshop was attended by: The assessment process involves:  Representatives of the commercial and  The synthesis of all relevant fisheries data recreational fishing sectors  Evaluation of fisheries‐independent  Fisheries Victoria managers, scientists and monitoring and research data, where compliance officers available  Catchment management representatives.  Convening a workshop for scientists, resource users and resource managers to This report assess the status of the stock/fishery in This report assesses the status of the Corner Inlet question fishery using monitoring data collected from  Production of an assessment report which commercial and recreational fisheries. provides scientific information and The report is structured as a series of sections information collected during the workshop which describe: relevant to fishery management.  The stock structure of key species harvested The assessment process: by the Corner Inlet fishery  Provides scientific evidence on the status of  The indicators of performance against the fish stocks and the environmental factors which the status of the stocks are assessed and harvest pressures that influence stock  The status matrix for each key fish stock in abundance the Corner Inlet fishery  Provides opportunity to draw on the  knowledge of stakeholder groups The integration of local knowledge  The fisheries that operate in Corner Inlet  Underpins evidence‐based decisions in an  ecologically sustainable development Fisheries management arrangements management context currently in place to control fishing effort  Complements Victorian fisheries These sections are underpinned by a series of management planning processes ‘Figures and Tables’ which:   Ensures the fishery assessment process is Detail the data used in the assessment accountable and transparent.  Summarise the life‐history of key species  Detail data collection methods.

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Stock structure of key species

Species Stock structure Australian salmon  Eastern Australian salmon (Arripis trutta) harvested from Corner Inlet is part of a single biological stock that is distributed from southern Queensland along the east coast of Australia to western Victoria and Tasmania  More than 90% of the total annual Victorian commercial catch of Australian salmon is the eastern species (MacDonald pers. comm.) Flounder (greenback and  Stock structure is unknown unspecified)  Flounder have an extended larval stage, capable of remaining in open ocean plankton for >30 days  This assessment assumes flounder in Corner Inlet are part of a larger stock Gummy shark  The most recent research on the stock structure of gummy shark suggests that there is likely one stock for southern Australia (extending from Bunbury in Western Australia to Jervis Bay in New South Wales) and a second stock in eastern Australia (extending from Newcastle to the Clarence River in New South Wales)  Gummy shark in Corner Inlet are assumed to be part of the larger southern Australian stock King George whiting  The stock composition of King George whiting in Victoria is unknown  King George whiting spawn and spend a substantial part of the life‐cycle in coastal waters  Sub‐adults are found in Victorian bays and inlets  Whiting in Corner Inlet are part of a larger but unknown stock Silver trevally  Silver trevally range from northern New South Wales to Western Australia.  Little is known of the stock structure. Preliminary research suggests that the silver trevally off south‐eastern Australia represent a single stock  This assessment assumes the silver trevally in Corner Inlet are part of a larger south‐eastern population Southern calamari  Stock structure is unknown  Individuals are capable of moving large distances (100s of kilometres)  This assessment assumes calamari in Corner Inlet are part of a larger stock Southern sea garfish  Stock structure is unknown Rock flathead  Stock structure is unknown

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Stock indicators and status key

The following ‘traffic light’ classification system has been developed to classify the status of individual finfish stocks.

Stock status Description Trend in five‐ Is the most recent classification year moving year above the long‐ average* term average** The indicator suggests that the stock is in good ↑↔ Yes condition. Current management arrangements are considered appropriate. ↔ The indicator suggests the stock is stable despite being ↔ No below the long‐term average. Current management arrangements may need to be assessed. Where appropriate, management responses to promote stock recovery need to be investigated. ↑ The indicator suggests that the stock is improving. ↑ No Current management arrangements are considered appropriate. ↓ The indicator suggests that the stock is decreasing. ↓ Yes/No Current management arrangements may need to be assessed. Where appropriate, management responses to promote stock recovery need to be investigated. The status of the stock is considered poor. Current ↓ No management arrangements need to be assessed. Management responses to promote stock recovery need to be investigated. A limited amount of information has been collected; or, there are inconsistent or contradictory signals in the data that preclude determination of stock status.

* Trend refers to a significant (P<0.1) linear change (ordinary least‐squares regression model) in the five‐year moving average of an indicator over the past 5 years; non‐significant trends were considered stable. ** Long‐term refers to the duration of the time‐series.

Corner Inlet‐Nooramunga Fisheries Assessment 2012

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8 Corner

The following tables classify the status of key species of the Corner Inlet‐Nooramunga fishery according to the ‘traffic light’ classification system using available indicators of stock status. Information to support the assessment are presented in the ‘Assessment figures and tables’ section of this

Inlet document. Table 1. Stock status determination using catch rate indicators for key species of the Corner Inlet and Nooramunga fishery. ‐ Nooramunga

Species Australian salmon Flounder Gummy shark King George Silver trevally Southern calamari Southern sea Rock flathead (greenback and whiting garfish unspecified)

Indicator Commercial haul Commercial haul Commercial mesh Commercial haul Commercial haul Commercial haul Commercial haul Commercial mesh Fishery seine catch rate seine catch rate net catch rate seine catch rate seine catch rate seine catch seine catch rate net catch rate (kg/shot) 30 year (kg/shot) 30 year (kg/km‐lift) 30 (kg/shot) 30 year (kg/shot) 30 year rate(kg/shot) 30 (kg/shot) 30 year (kg/km‐lift) (Figure time series time series year time series time series time series year time series time series 17)

Assessment (Figure 8) (Figure 9) (Figure 10) (Figure 11) (Figure 14) (Figure 15) (Figure 16) Minimum 0.06 0.78 2.54 7.48 1.26 0.04 5.75 6.54 Maximum 79.57 6.19 15.42 40.91 22.02 14.65 32.93 94.28 Ten‐year average 4.39 3.49 12.03 18.57 11.35 9.48 17.67 73.28 Five‐year 5.47 3.63 12.74 21.90 13.56 11.07 17.29 75.47

2012 average 2010/11 6.03 4.92 14.13 20.94 6.96 13.25 16.57 89.55 Trend in five‐ ↑ ↔ ↔ ↔ ↑ ↑ ↔ ↔ year moving average Above long‐term No Yes Yes Yes No Yes No Yes average Status Limited data Limited data Limited data Limited data Limited data Limited data Limited data Limited data Status Data are inadequate Data are inadequate Data are inadequate Data are inadequate Data are inadequate Data are inadequate Data are inadequate Data are inadequate to classification to assess the status to assess the status to assess the status to assess the status to assess the status to assess the status to assess the status assess the status of notes of salmon in Corner of flounder in of gummy shark in of whiting in Corner of silver trevally in of calamari in of garfish in Corner rock flathead in Inlet due to: Corner Inlet due to: Corner Inlet due to: Inlet due to: Corner Inlet due to: Corner Inlet due to: Inlet due to: Corner Inlet due to: ‐ Gear modifications ‐ Gear modifications ‐ Gear modifications ‐ Gear modifications ‐ Gear modifications ‐ Gear modifications ‐ Gear modifications ‐ Gear modifications The above factor is ‐ Significant ‐ Increased soak‐ ‐ Significant The above factor is The above factor is ‐ Significant ‐ Increased soak‐time increasing gear decreases in seagrass time decreases in seagrass increasing gear increasing gear decreases in seagrass ‐ Significant decreases efficiency abundance The above factors are abundance efficiency efficiency abundance in seagrass abundance Salmon in Corner The above factors are increasing gear The above factors are Trevally in Corner Calamari in Corner The above factors are The above factors are Inlet are also part increasing gear efficiency increasing gear Inlet are also likely Inlet are also likely increasing gear increasing gear larger stock that efficiency Gummy shark in efficiency part of a larger stock part of a larger stock efficiency efficiency extends outside the Flounder in Corner Corner Inlet are also Whiting in Corner that extends outside that extends outside It is unclear whether It is unclear whether inlet Inlet are also likely part of a larger stock Inlet are also part of the inlet the inlet the garfish in Corner the rock flathead in part of a larger stock that extends outside a larger stock that Inlet are part of a Corner Inlet are part that extends outside the inlet extends outside the larger stock of a larger stock the inlet inlet

Assessment figures and tables

Figure 1. Map of Corner Inlet and Nooramunga showing commercial fishing zones numbered 1 to 5.

600 3.0 Seine Mesh Hooks Unspecified Value 500 2.5

400 2.0 ($ million) Value

300 1.5

(tonnes) Catch 200 1.0

100 0.5

0 0.0

78/79 79/80 80/81 81/82 82/83 83/84 84/85 85/86 86/87 87/88 88/89 89/90 90/91 91/92 92/93 93/94 94/95 95/96 96/97 97/98 98/99 99/00 00/01 01/02 02/03 03/04 04/05 05/06 06/07 07/08 08/09 09/10 10/11

Figure 2. Trends in annual commercial catch (tonnes) and wholesale market value for the Corner Inlet‐ Nooramunga fishery. In 1995/96, there were 33 commercial access licences for the Corner Inlet‐Nooramunga fishery. Voluntary licence buy‐backs in 1999/00 and 2005/06 reduced the number of licences to 20 and 18 respectively; there are currently 18 commercial fishery access licences.

Corner Inlet‐Nooramunga Fishery Assessment 2012

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3,000 Seine Mesh Hooks Unspecified 2,500

2,000

1,500 Effort (days) 1,000

500

0

78/79 79/80 80/81 81/82 82/83 83/84 84/85 85/86 86/87 87/88 88/89 89/90 90/91 91/92 92/93 93/94 94/95 95/96 96/97 97/98 98/99 99/00 00/01 01/02 02/03 03/04 04/05 05/06 06/07 07/08 08/09 09/10 10/11 Figure 3. Trends in annual commercial fishing effort (days) for the Corner Inlet‐Nooramunga fishery.

Table 2. Commercial effort (tonnes) statistics of the main fishing methods used to harvest finfish species in Corner Inlet‐Nooramunga. Fishing Method Effort 10‐year average 5‐year average 2010/11 Trend Haul seine (shots) 2850 2494 2419 ↓ Mesh net (km‐lifts) 657 734 766 ↑

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500 Flathead, Rock Whiting, King George Garfish, Southern sea Calamary, Southern Silver Trevally Australian salmon Shark, Gummy Flounder, Uspec Skates and rays, Unspec Mullet, Yellow-Eye Pike, Unspecified Flathead, Sand Leatherjacket Stranger Other

400

300

Annual catch (tonnes) catch Annual 200

100

0

78/79 79/80 80/81 81/82 82/83 83/84 84/85 85/86 86/87 87/88 88/89 89/90 90/91 91/92 92/93 93/94 94/95 95/96 96/97 97/98 98/99 99/00 00/01 01/02 02/03 03/04 04/05 05/06 06/07 07/08 08/09 09/10 10/11 Figure 4. Trends in annual commercial harvest (tonnes) of key finfish species of the Corner Inlet‐Nooramunga fishery.

Table 3. Commercial catch (tonnes) statistics of key finfish species of the Corner Inlet‐Nooramunga fishery. Species Fishing method Catch (tonnes) (fishing method % of species’ total catch) 10‐year 5‐year 2010/11 Trend average average Australian salmon (Figure 8) Haul seine (91%) 12.2 13.5 14.6 ↑ Flounder (greenback and unspecified) (Figure 9) Haul seine (91%) 9.7 9.1 11.9 ↑ Gummy shark (Figure 10) Mesh net (82%) 8.0 9.2 10.8 ↑ King George whiting (Figure 11) Haul seine (90%) 52.0 55.8 50.7 ↓ Silver trevally (Figure 14) Haul seine (96%) 31.9 33.8 16.8 ↓ Southern calamari (Figure 15) Haul seine (99%) 25.9 26.8 32.1 ↑ Southern sea garfish (Figure 16) Haul seine (99%) 50.2 42.6 40.1 ↓ Rock flathead (Figure 17) Mesh net (70%) 39.3 45.0 53.3 ↑

Corner Inlet‐Nooramunga Fishery Assessment 2012

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70 Rock flathead King George whiting

60 Gummy shark

Southern sea garfish

50 Australian salmon

Southern calamari 40 Silver trevally Greenback flounder 30

20

Proportion of species' catch (%) 10

0 12345 Fishing zone

Figure 5. The proportion of key species’ catch harvested from each fishing zone in Corner Inlet‐ Nooramunga. Data is from 2006/07‒2009/10 combined.

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100 Retained catch

2000/01 (Anglers n=42; Trips n=183) 80 2006/07 (Anglers n=35; Trips n=152)

60

40

20

0

100 Released catch Frequency (%) 2000/01 (Anglers n=42; Trips n=183) 80 2006/07 (Anglers n=35; Trips n=152)

60

40

20

0

Trevally Salmon Snapper Other sp.

whiting Sharks/rays King George King (all) Flathead Figure 6. Composition of retained and released catch by recreational anglers from telephone survey data (Ryan et al. 2009; Henry and Lyle 2003) for Corner Inlet.

800

600

400

200 Number trips (×1000) of

0 Port Phillip Western Gippsland Mallacoota Corner Bay Port Lakes Inlet Inlet

Figure 7. Estimated regional recreational fishing effort from telephone survey data (Henry and Lyle 2003).

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Corner Inlet - Australian salmon - Haul seine Gear: ES, BS, GS, RN, H1, H2, H3, H4, H5, H6 Catch (tonnes) Effort (shots) Catch rate (kg/shot) 150--4000 80 -3000 60

100- ate h R -2000 Effort Catch 40

Catc 50- -1000 20

0 78/79 79/80 80/81 81/82 82/83 83/84 84/85 85/86 86/87 87/88 88/89 89/90 90/91 91/92 92/93 93/94 94/95 95/96 96/97 97/98 98/99 99/00 00/01 01/02 02/03 03/04 04/05 05/06 06/07 07/08 08/09 09/10 10/11

Haul seine catch rate Five-year moving average Five-year average 14 Ten-year average Long-term average (30 years) 12

10

8

6 Catch rate (kg/shot) rate Catch 4

2 0 2001/022001 2003/04 2003 2005/06 2005 2007/08 2007 2009/10 2009

Figure 8. Annual commercial catch (tonnes) and catch rate (kg/shot) of Australian salmon, and effort (shots) targeting Australian salmon and other species in Corner Inlet‐Nooramunga by haul seine from 1978/79 to 2010/11.

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Corner Inlet - Flounder, Greenback/Unspecified - Haul seine Gear: ES, BS, GS, RN, H1, H2, H3, H4, H5, H6

Catch (tonnes) Effort (shots) Catch rate (kg/shot) 20--4000 8

15--3000 6 ate h R 10--2000 Effort Catch 4 Catc 5--1000 2

0

78/79 79/80 80/81 81/82 82/83 83/84 84/85 85/86 86/87 87/88 88/89 89/90 90/91 91/92 92/93 93/94 94/95 95/96 96/97 97/98 98/99 99/00 00/01 01/02 02/03 03/04 04/05 05/06 06/07 07/08 08/09 09/10 10/11

Mesh net catch rate Five-year moving average 6 Five-year average Ten-year average Long-term average (30 years) 5

4

3

2 (kg/shot) rate Catch

1

0 2001 2003 2005 2007 2009 2001/02 2003/04 2005/06 2007/08 2009/10

Figure 9. Annual commercial catch (tonnes) and catch rate (kg/shot) of flounder (greenback and unspecified), and effort (shots) targeting flounder and other species in Corner Inlet‐Nooramunga by haul seine from 1978/79 to 2010/11.

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Corner Inlet - Shark, gummy - Mesh net Gear: MM, M1, M2, M3, M4, M5, M6,N1,N2,N3,N4

Catch (tonnes) Effort (km-lifts) Catch rate (kg/km-lift) 15--1500 20

15 10--1000 ate h R Effort Catch 10 Catc 5--500 5

0

78/79 79/80 80/81 81/82 82/83 83/84 84/85 85/86 86/87 87/88 88/89 89/90 90/91 91/92 92/93 93/94 94/95 95/96 96/97 97/98 98/99 99/00 00/01 01/02 02/03 03/04 04/05 05/06 06/07 07/08 08/09 09/10 10/11

18

16 14 12 10 8

6 Mesh net catch rate (kg/km-lift) rate Catch Five-year moving average 4 Five-year average Ten-year average 2 Long-term average (30 years) 0 2001/022001 2003/04 2003 2005/06 2005 2007/08 2007 2009/10 2009

Figure 10. Annual commercial catch (tonnes) and catch rate (kg/km‐lift) of gummy shark, and effort (km‐lifts) targeting Australian salmon and other species in Corner Inlet‐Nooramunga by haul seine from 1978/79 to 2010/11.

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Corner Inlet - Whiting, King George - Haul seine Gear: ES, BS, GS, RN, H1, H2, H3, H4, H5, H6

Catch (tonnes) Effort (shots) Catch rate (kg/shot) 150--4000 50

-3000 40

100- ate

30 h R -2000 Effort Catch

20 Catc 50- -1000 10 0 78/79 79/80 80/81 81/82 82/83 83/84 84/85 85/86 86/87 87/88 88/89 89/90 90/91 91/92 92/93 93/94 94/95 95/96 96/97 97/98 98/99 99/00 00/01 01/02 02/03 03/04 04/05 05/06 06/07 07/08 08/09 09/10 10/11

30

25

20

15

10 Mesh net catch rate Catch rate (kg/shot) rate Catch Five-year moving average Five-year average 5 Ten-year average Long-term average (30 years) 0 2001/022001 2003/04 2003 2005/06 2005 2007/08 2007 2009/10 2009

Figure 11. Annual commercial catch (tonnes) and catch rate (kg/shot) of King George whiting, and effort (shots) targeting King George whiting and other species in Corner Inlet‐Nooramunga by haul seine from 1978/79 to 2010/11.

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20 18 2006/07 16 14 n=3718 12 10 8 6 4 2 0 20 25 30 35 40 45 50 20 18 2007/08 16 n=3503 14 12 10 8 6 4 2 0 20 25 30 35 40 45 50 20 18 2008/09 16 14 n=3475 12 10 8 6 4 2 0

(%) frequency Weighted 20 25 30 35 40 45 50 20 18 2009/10 16 n=3090 14 12 10 8 6 4 2 0 20 25 30 35 40 45 50 20 18 2010/11 16 n=3624 14 12 10 8 6 4 2 0 20 25 30 35 40 45 50

Fish total length (cm)

Figure 12. Length‐frequency distributions of King George whiting harvested by commercial haul seines in Corner Inlet‐Nooramunga from 2006/07 to 2010/11. Data is available from 1994/95 to 2010/11. Samples for fish length were provided by one commercial fisher.

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100

80 2003/04 n=90 aged; 3456 measured 60

40

20

0 012345678910 100 2004/05 80 n=186 aged; 3434 measured 60

40

20

0 012345678910 100 2008/09 80 n=94 aged; 3475 measured 60

40

20 (%) Frequency 0 012345678910 100

80 2009/10 n=65 aged; 3090 measured 60

40

20

0 012345678910 100

80 2010/11 n=198 aged; 3624 measured 60

40

20

0 012345678910 Estimated age (spawning year) Estimated age (years)

Figure 13. Age‐frequency distributions of King George whiting harvested by commercial haul seines in Corner Inlet‐Nooramunga from 2003/04 to 2010/11 (excluding 2005/06−2007/08). Data is available from 1994/95 to 2010/11, excluding 1996/97−1997/98 and 2005/06−2007/08. Samples for fish length were provided by one commercial fisher.

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Corner Inlet - Trevally, silver - Haul seine Gear: ES, BS, GS, RN, H1, H2, H3, H4, H5, H6

Catch (tonnes) Effort (shots) Catch rate (kg/shot) 60--4000 25

-3000 20

40- ate

15 h R -2000 Effort Catch

10 Catc 20- -1000 5

0

78/79 79/80 80/81 81/82 82/83 83/84 84/85 85/86 86/87 87/88 88/89 89/90 90/91 91/92 92/93 93/94 94/95 95/96 96/97 97/98 98/99 99/00 00/01 01/02 02/03 03/04 04/05 05/06 06/07 07/08 08/09 09/10 10/11

25 Haul seine catch rate

Five-year moving average Five-year average 20 Ten-year average Long-term average (30 years)

15

10

(kg/shot) rate Catch

5

0 2001 2003 2005 2007 2009 2001/02 2003/04 2005/06 2007/08 2009/10 Figure 14. Annual commercial catch (tonnes) and catch rate (kg/shot) of silver trevally, and effort (shots) targeting silver trevally and other species in Corner Inlet‐Nooramunga by haul seine from 1978/79 to 2010/11.

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Corner Inlet - Calamari, southern - Haul seine Gear: ES, BS, GS, RN, H1, H2, H3, H4, H5, H6

Catch (tonnes) Effort (shots) Catch rate (kg/shot) 40--4000 15

30--3000

ate 10

h R 20--2000 Effort Catch

Catc 5 10--1000

0

78/79 79/80 80/81 81/82 82/83 83/84 84/85 85/86 86/87 87/88 88/89 89/90 90/91 91/92 92/93 93/94 94/95 95/96 96/97 97/98 98/99 99/00 00/01 01/02 02/03 03/04 04/05 05/06 06/07 07/08 08/09 09/10 10/11

16 Haul seine catch rate Five-year moving average Five-year average 14 Ten-year average

12 Long-term average (30 years)

10

8

6 (kg/shot) rate Catch 4

2

0

2001/022001 2003/04 2003 2005/06 2005 2007/08 2007 2009/10 2009

Figure 15. Annual commercial catch (tonnes) and catch rate (kg/shot) of southern calamari, and effort (shots) targeting southern calamari and other species in Corner Inlet‐Nooramunga by haul seine from 1978/79 to 2010/11.

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Corner Inlet - Garfish, southern sea - Haul seine Gear: ES, BS, GS, RN, H1, H2, H3, H4, H5, H6

Catch (tonnes) Effort (shots) Catch rate (kg/shot) 80--4000 40

60--3000 30 ate h R 40--2000 Effort Catch 20

Catc

20--1000 10

0

78/79 79/80 80/81 81/82 82/83 83/84 84/85 85/86 86/87 87/88 88/89 89/90 90/91 91/92 92/93 93/94 94/95 95/96 96/97 97/98 98/99 99/00 00/01 01/02 02/03 03/04 04/05 05/06 06/07 07/08 08/09 09/10 10/11

24

22

20

18

16

Catch rate (kg/shot) rate Catch Haul seine catch rate 14 Five-year moving average Five-year average 12 Ten-year average Long-term average (30 years) 10 2001 2003 2005 2007 2009 2001/02 2003/04 2005/06 2007/08 2009/10

Figure 16. Annual commercial catch (tonnes) and catch rate (kg/shot) of southern sea garfish, and effort (shots) targeting southern sea garfish and other species in Corner Inlet‐Nooramunga by haul seine from 1978/79 to 2010/11.

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Corner Inlet - Flathead, rock - M12 Mesh net Gear: M1, M2

Catch (tonnes) Effort (km-lifts) Catch rate (kg/km-lift) 60--800 100

-600 80

40- ate

60 h R -400 Effort Catch

40 Catc 20- -200 20

0

78/79 79/80 80/81 81/82 82/83 83/84 84/85 85/86 86/87 87/88 88/89 89/90 90/91 91/92 92/93 93/94 94/95 95/96 96/97 97/98 98/99 99/00 00/01 01/02 02/03 03/04 04/05 05/06 06/07 07/08 08/09 09/10 10/11

90

80

70 60

50

40

30 Mesh net catch rate

(kg/km-lift) rate Catch Five-year moving average 20 Five-year average Ten-year average 10 Long-term average (30 years)

0

2001/022001 2003/04 2003 2005/06 2005 2007/08 2007 2009/10 2009

Figure 17. Annual commercial catch (tonnes) and catch rate (kg/km‐lift) of rock flathead, and effort (km‐lifts) targeting rock flathead and other species in Corner Inlet‐Nooramunga by mesh net from 1978/79 to 2010/11.

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20 2006/07 n=1066 15

10

5

0 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 20 2007/08 n=315 15

10

5

0 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 20 2008/09

15 n=1498 Weighted frequency (%) frequency Weighted

10

5

0 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100

20 2009/10

n=127 15

10

5

0 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100

Fish total length (cm)

Figure 18. Length‐frequency distributions of rock flathead harvested by commercial mesh nets in Corner Inlet‐Nooramunga from 2006/07 to 2009/10. Data is available from 1994/95 to 2009/10, excluding 2001/02 to 2005/06 and 2010/11. Samples for fish length were provided by two commercial fishers.

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80 1996/97 60 n=105 aged; 292 measured 40 20 0

96/97 94/95 92/93 90/91 88/89 86/87 84/85 82/83 80/81 78/79 76/77 74/75 72/73 70/71 68/69 66/67 80 1998/99 60 n=259 aged; 590 measured 40 20 0

98/99 96/97 94/95 92/93 90/91 88/89 86/87 84/85 82/83 80/81 78/79 76/77 74/75 72/73 70/71 68/69 80 2007/08

Frequency (%) Frequency 60 n=208 aged; 315 measured 40 20 0

07/08 05/06 03/04 01/02 99/00 97/98 95/96 93/94 91/92 89/90 87/88 85/86 83/84 81/82 79/80 77/78 80 2009/10 60 n=211 aged; 127 measured

40

20

0

09/10 07/08 05/06 03/04 01/02 99/00 97/98 95/96 93/94 91/92 89/90 87/88 85/86 83/84 81/82 79/80 Spawning year

Figure 19. Cohort strength distributions of rock flathead harvested by commercial mesh nets in Corner Inlet‐Nooramunga from 1996/97 to 2009/10 (excluding 1997/98, 1999/00−2006/07 and 2008/09). Data is available from 1995/96 to 2009/10, excluding 1999/00−2006/07 and 2008/09. Samples for fish length were provided by two commercial fishers.

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Table 4. Summary of length‐frequency distributions of King George whiting and rock flathead commercial catches in Corner Inlet.

Species King George whiting Rock flathead Indicator Haul seine size (TL)‐frequency Mesh net length (TL)‐frequency distribution time‐series of retained distribution time‐series of retained catch (1994/95‒ 2010/11) catch (1994/95 to 2009/10, excluding (Figure 12). Samples were provided 2001/02−2005/06 and 2010/11) by one commercial fisher. (Figure 18). Samples were provided by two commercial fishers. Minimum 20 cm 26 cm Maximum 51 cm 66 cm 2010/11: 44 cm 2009/10: 55 cm Mean (10‐year average) 32 cm N/A Mean (5‐year average) 33 cm N/A Mean (most recent) 2010/11: 32 2009/10: 42 cm Mode (most recent) 2010/11: 28 cm (bi‐modal 2009/10: 39 cm distribution ‐ second mode at 37 cm) Size frequency distribution 2010/11 is significantly different to 2009/10 is significantly different to significance test (Kilmogrorov‐ 2003/04 to 2009/10 (due to highly all available years prior Smirnoff) results (p<0.001) variable inter‐annual recruitment) (1994/95−1996/97, 1998/99 and 2006/07−2008/09) Proportion of retained catch ≥ ≥38 cm TL ≥45 cm TL 2010/11: 9% 2009/10: 20% Trend in five‐year moving average Trend in five‐year moving average over the past 10 years: Increasing over the past 10 years: N/A Trend in five‐year moving average Trend in five‐year moving average over the past 5 years: Stable over the past 5 years: N/A Proportion of retained catch ≤30 2010/11: 53% 2009/10: 0% cm TL (size at first maturity for (inter‐annual variability is high King George whiting is 30‒35 cm due to variable recruitment) TL; and for rock flathead is unknown, however, is <30 cm TL for other closely related species) Status Limited data Limited data

Table 5. Summary of age‐frequency distributions of King George whiting and rock flathead commercial catches in Corner Inlet.

Species King George whiting Rock flathead Indicator Haul seine age (years)‐frequency Mesh net age (years)‐frequency distribution time‐series of retained catch distribution time‐series of retained (1994/95 to 2010/11, excluding catch (1995/96 to 2009/10, excluding 1996/97−1997/98 and 2005/06−2007/08) 1999/00−2006/07 and 2008/09) (Figure (Figure 13). Samples for fish length were 18). Samples for fish length were provided by one commercial fisher. provided by two commercial fishers. Minimum 1 yrs 2 yrs Maximum 4 yrs 20 yrs 2010/11: 3 yrs 2009/10: 24 yrs Mean (10‐year average) N/A N/A Mean (5‐year average) N/A N/A Mean (most recent) 2010/11: 2 yrs 2009/10: 8 yrs Mode (most recent) 2010/11: 1 yrs 2009/10: 5 yrs (bimodal distribution – second mode at 7 yrs) Status Limited data Limited data

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Integrating local Knowledge

It is widely recognised that both scientific and Which locations within Corner Inlet‐ local knowledge are important in assessing Nooramunga do you fish for the previously natural resources. As part of the assessment mentioned target species? (multiple locations process for the Corner Inlet fishery, commercial and recreational fishers were provided with can be reported for each species): semi‐structured local knowledge surveys. Area 1 2 3 4 5 The surveys were designed to give stakeholder groups an opportunity to provide information King George whiting (6) (5) (4) (2) on the status of the Corner Inlet fishery; to fill Garfish (4) (4) (3) (1) (1) current information gaps, and to complement Rock flathead (3) (3) (3) scientific knowledge. Silver trevally (1) (1) (1) (1) Survey groups Gummy shark (1) (1) (1) Calamari (1) (1) (1) Commercial:

 There are currently 18 commercial What factors do you believe may be influencing fishery access licenses in Corner Inlet‐ catches of ‘insert insert main target species’? Nooramunga. King George whiting  Each of the access license holders were provided with a mail‐out survey; eight Decreasing catch rates: access licence holders responded.  Seagrass loss (2) Recreational:  Increased catch/effort by recreational fishing  Nine recreational fishers from the sector (1) General Angler Diary Program that fish in Corner Inlet were surveyed over the Increasing catch rates telephone.  Gear (2)  Nets being left in water for too long (1) Results  Refined gear/equipment (1) Commercial fishers: Fluctuations in catch rates: List the three species you most commonly target  Recruitment (1) in Corner Inlet (number of responses):  King George whiting (7) Rock flathead  Garfish (5) Decreasing catch rates:  Rock flathead (4)  Calamari (2)  Seagrass loss (2)  Silver trevally (1)  Increased targeted effort for rock flathead (1)  Gummy shark (1)  Weather (three very wet/windy years) (1)  Increased recreational catch/effort (1) Out of the three target species previously mentioned, what is your main target species Recreational fishers: when fishing in Corner Inlet?  King George whiting (5) What was the trend in recreational fishing  Rock flathead (2) pressure over the past 5 years?  Garfish (1)  Increased (7)  Similar (1)  Decreased (0)

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Commercial and recreational fisher responses to survey: Source Number of respondents/’Why did you say that?’ How would you best describe the abundance of legal‐sized King George whiting over the past 12 months compared with previous years? Increased Similar Decreased Unsure Commercial 2 1 2 0 ‘There has been good ‘The abundance of whiting numbers of small legal‐ has been low in areas sized whiting in the last normally fished’ year’ ‘Good recruitment was observed two years ago (leading up to 2011)’ Recreational 2 2 1 0 ‘Catch rates have increased this year’ How would you best describe the abundance of under‐sized King George whiting over the past 12 months compared with previous years? Commercial 0 0 4 0 ‘Abundance of small whiting is currently low’ Recreational 1 0 0 3 ‘Usually don’t catch under‐sized whiting’ Would you say the average size of legal‐sized King George whiting that you’ve caught over the past 5 years has gotten bigger, smaller or is about the same? Bigger About the same Smaller Unsure Commercial 1 3 1 0 Recreational 2 3 0 0 ‘Good run of larger whiting this year’ How would you describe the status of King George whiting? Good Improving Deteriorating Unsure Commercial 2 0 2 0 ‘Catches have been good ‘With no under‐sized fish for the past year’ around it is expected that the next year will be poor’ ‘Abundance is currently low’ Recreational 4 0 1 0 ‘Two of us (in the boat) ‘Hard to get 10 whiting are catching 30‐35 per trip’ whiting per trip’

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Commercial and recreational fisher responses to survey: Source Number of respondents/’Why did you say that?’ How would you best describe the abundance of legal‐sized garfish over the past 12 months compared with previous years? Increased Similar Decreased Unsure Commercial 0 0 1 0 ‘Abundance of garfish has been low in areas normally fished’ How would you best describe the abundance of legal‐sized rock flathead over the past 12 months compared with previous years? Commercial 0 1 1 0 Recreational 0 1 0 0 How would you best describe the abundance of legal‐sized flathead over the past 12 months compared with previous years? Recreational 2 3 0 0 ‘I have increased my catch rates by fishing in shallower water with plastics’ How would you best describe the abundance of under‐sized flathead over the past 12 months compared with previous years? Recreational 2 0 0 3 ‘Increased catch rates of ‘Usually don’t catch undersized’ under‐sized flathead’ Would you say the average size of legal‐sized rock flathead that you’ve caught over the past 5 years has gotten bigger, smaller or is about the same? Bigger About the same Smaller Unsure Commercial 0 2 0 0 Recreational 0 0 1 0 Would you say the average size of legal‐sized flathead that you’ve caught over the past 5 years has gotten bigger, smaller or is about the same? Recreational 2 0 3 0 How would you describe the status of rock flathead? Good Improving Deteriorating Unsure Commercial 0 0 2 0 ‘Abundance is declining’ Recreational 1 0 0 0 How would you describe the status of flathead? Recreational 2 1 1 1 ‘Size of flathead is going down’

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Other local knowledge provided on the changed. This has resulted in increased effort status of the fishery in Corner Inlet: and consistency’ Environment Rock flathead:  ‘Seagrass continues to decline, particularly in  ‘Increased effort targeting rock flathead’ fishing zone 2’ King George whiting:  ‘Broad‐leaf/red swimmer crabs (Nectocarcinus  ‘The abundance of King George whiting is integrifrons) have disappeared from the inlet’; patchy in the inlet’ ‘The decline occurred over a short period of  ‘ A lack of healthy fine‐leaf seagrass is time (~6 months)’ causing the patchy abundance’  ‘The broad‐leaf crab was an important food Gummy shark: source for flathead, gummy shark, flounder’  ‘Catch and effort for gummy shark have  ‘The absence of broad‐leaf crabs in the inlet increased’ have resulted in rock flathead consuming  ‘Under‐size and 50‐55 cm gummy shark are more leather jackets and cobblers to replace abundant’ loss of crabs in the diet’  ‘Gummy shark is only targeted when other  ‘Leather jackets and cobblers are less species are not available’ abundant’  ‘There have been good numbers of gummy  There is concern: that the Pacific sea star shark for the past five years’ (Asterias amurensis) is moving into the inlet; that there is an increased abundance of Silver trevally: filamentous green/brown algae (‘slub’);  ‘Abundance has been low for the past two regarding use of the catchment in general: years’ agriculture, pesticides, maintenance of Flounder: drains etc.; regarding the effects of  ‘Flounder are not abundant in the inlet’ catchment use on seagrass loss.  ‘Broccoli weed (Codium fragile), an invasive species of algae, has limited the effectiveness Commercial fishing of flounder nets’ Catch rates:  ‘A dedicated fishery for flounder in the 1970s  ‘Continued loss of seagrass is resulting in is no longer there’ seagrass associated species having less  ‘The use of flounder nets has declined as their protection from commercial fishing’ use is very labour intensive’  ‘Lack of seagrass means haul seines are working the substrate harder, catching more Recreational fishing smaller fish’  ‘There has been a significant increase in  ‘The decline of crabs in the inlet has allowed recreational fishing effort in the inlet’ commercial fishers to increase the soak time  ‘An overflow of anglers from the Melbourne of nets in recent years’ area is contributing to the increased effort’  ‘Gear modifications in recent years,  ‘Recreational targeting for snapper has including, increasing the weight of haul increased in the inlet over the past few years’ seines has resulted in an increase in catch of  ‘There has been an increase in larger smaller fish, in particular rock flathead’ recreational fishing vessels with increased  ‘There are now younger operators in the capabilities’ commercial fishery; licences holders have

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In general, how satisfied are you with the current fishing conditions in Corner Inlet?

Fishing satisfaction for KGW Very satisfied Satisfied

Unsatisfied

Commercial 1 24

Recreational 3 2

0% 20% 40% 60% 80% 100%

Why do you say that?  ‘Fishing over past year has not been as good as other years’  ‘The increase in rock flathead being harvested is decreasing catch rates; fishers are having to modify fishing practises to maintain catch rates’  ‘Seagrass loss and marine park restrictions have resulted in substantial loss of available/suitable fishing ground’

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Overview of assessment data collection methods

Source Description Commercial Victorian commercial fishers are required as a condition of their licence to record fishery‐ their fishing activities in a logbook and to submit this information to the dependent Department of Primary Industries on a monthly basis. Commercial fishers provide the following information:  Gear code and net length/number of hooks/jigs  Area code  Number of shots  Fishing time  Weight of species caught and retained. Recreational A voluntary general angler diary (GAD) program, established in 1997, provides fishery‐ time‐series data on recreational angler catch rates, and the size composition of dependent key target species. Length and Since the 1990s there has been opportunistic sampling of length and age‐ age frequency data for key species landed by commercial and recreational fishers. monitoring To generate the commercial length‐frequency distributions, a sub‐sample of fish harvested by a commercial fisher is measured; a ratio of the weight of the sub‐ sample to the weight of the total catch is then used to estimate the size distribution of the total catch. Otoliths used for ageing are prepared and aged following standard procedures outlined in Morison et al. (1998). Age‐frequency distributions are estimated applying age‐length keys to length‐ frequency distributions. A nominal birth date of 1 January is assigned when ageing rock flathead; and 1 July is assigned when ageing King George whiting. Age information for rock flathead is presented by spawning year for rock flathead so abundant year‐classes can be identified and tracked across multiple spawning years. Ages of rock flathead referred to in this report represent the age of a particular year‐class as of 1 January. Local Local knowledge surveys are circulated to commercial and recreational fishers to knowledge provide information on the status of fish stocks/fisheries. Comments provided in commercial logbook returns and telephone correspondence in the past 12 months is also collated.

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Description of the Corner Inlet‐ Nooramunga commercial fishery

General  Total commercial harvest of finfish in 2010/11 was 334 tonnes. description  In 2010/11, commercial catches comprised 42 species/groups: o Nine key species constituted the majority of the total harvest (81% by weight, 88% by value). Rock flathead constituted 23% (by weight), King George whiting (16%), southern sea garfish (12%), calamari (10%), silver trevally (5%), Australian salmon (4%), gummy shark (4%), unspecified flounder (4%), skates and rays (4%) of the total commercial catch. Fishing  Haul seines and mesh nets are the main commercial methods used to catch finfish methods in Corner Inlet: o In 2010/11, haul seines harvested 71% of the commercial catch; mesh nets harvested the remaining 29%.  Haul seines harvest the majority of King George whiting (90%), southern sea garfish (99%), calamari (99%), silver trevally (96%), Australian salmon (91%), skates and rays (91%) and unspecified flounder (91%; however historically, the majority of flounder were harvested by mesh nets – specialist flounder nets. The use of specialist flounder nets virtually ceased in the late 1990s).  Mesh nets harvest the majority of rock flathead (70%) and gummy shark (82%). Fishing  The majority of the commercial catch is harvested from fishing zones 1 and 2 areas and (Figure 5) (see map in Figure 1 for fishing zone location). seasonality  When catches of King George whiting are low, targeting of rock flathead and southern sea garfish increases (e.g. see 2009/10 where there was an increase in mesh net effort to target rock flathead, and garfish were being targeted by haul seines).  Southern calamari have been targeted in Corner Inlet‐Nooramunga since the late 1990s; increased catches since then are the result of the market and improved fishing techniques. Since the 1980s, Australian salmon have been harvested as by‐catch and are generally not targeted; this is the result of the market.

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Overview of management arrangements

Commercial fishery Recreational fishery  Commercial catches in Corner Inlet‐  Recreational fishing licence: Nooramunga occur as a component o Since 15 July 1999, recreational fishers have been of a multi‐species commercial finfish required to hold a recreational fishing licence fishery. (RFL) to fish in marine and inland waters.  The commercial fishery is currently Recreational fishers under 18 years of age or over managed primarily by: 70 years of age, or those holding one of a range of o Input (effort) controls concession cards are not required to hold a licence. (including limited entry  Gear restrictions: licensing, restrictions on fishing o Recreational fishing remained unrestricted, other equipment and methods, and than size limits, until 1992, when regulations closed areas/seasons) specified a maximum of four lines per person and o Indirect catch controls such as two hooks per line when fishing in marine waters, legal minimum size limits. and a maximum of two lines with two hooks per  The number of licensed commercial line in inland waters. This regulation was modified fishers in Victorian waters was in 2009 to include two hooks per line or one bait jig reduced to a third between 1986/87 when fishing in both marine and inland waters. and 2010/11. The majority of the  Bag and size limits: licence removals occurred as a result o Species‐specific daily bag limits (DBL) and of voluntary licence buy‐back minimum legal size limits apply to recreational schemes conducted in 1999/00 and fishing in Corner Inlet. See the current Victorian 2005/06. Recreational Fishing Guide for details.  In 20010/11, there were 18 commercial licence holders in the Corner Inlet.

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Key species’ life‐history information

Eastern Distribution  The eastern species occurs along the coast of east Australian states, New Zealand and nearby oceanic islands; the western species occurs from Western Australia, to Victoria and Tasmania (Gomon et al. Australian and movement 2008). salmon,  Forms large migratory schools that move along the coast in near shore waters (Gomon et al. 2008). Arripis trutta; Reproduction  Eastern species spawns in the coastal waters of Victoria and New South Wales; western species spawns in Western Australia. western Growth  Maximum length of the eastern species is 55 cm TL; western species is 75 cm TL (Gomon et al. 2008). Australian Diet  Juveniles (<15 cm SL) in Port Phillip Bay consume benthic and pelagic crustaceans and fish (Hindell et salmon, A. al. 2000).  Sub‐adults (20‒35 cm SL) in Western Port, consume anchovy, pilchard and sandy sprat (Hoedt and truttacea Dimmlich 1994). Greenback Distribution  Occur from southern New South Wales to Western Australia, including Tasmania, and New Zealand and (Gomon et al. 2008). flounder, movement  Found in sheltered bays and inshore waters, to a depth of 100 m (Gomon et al. 2008). Rhombosolea  Juveniles occur over unvegetated habitat (Edgar and Shaw 1995; Jenkins et al. 1997).  Has an extended larval stage capable of remaining in open ocean plankton (Gomon et al. 2008). tapirina Reproduction  Spawning in Tasmania occurs in estuaries and coastal waters, from June to October (Crawford 1984).  In Tasmania, size at first maturity for females and males is 218 and 190 mm TL, respectively (Crawford 1984).  Forms sex‐specific aggregations (Crawford 1984).  Larvae hatch at 1.9 mm, and remain in the plankton for 30 days (Jenkins et al. 1993). Growth  Maximum length of 45 cm TL (Gomon et al. 2008). Diet  The diet of larvae consists of the larval stages of bivalves, copepods and invertebrate eggs (Jenkins 1987).  Juveniles feed on copepods and small crustaceans (Shaw and Jenkins 1992). Gummy Distribution  Occur in southern Australian waters from southern Queensland to similar latitude in Western and Australia, including Tasmania (Kuiter 2000). shark, movement  Demersal, found to a depth of 300 m, but are generally found in waters < 80 m deep (Gomon et al. Mustelus 2008). Reproduction  Males and females mature at 80 and 85 cm TL (Gomon et al. 2008). antarcticus  Gives birth to live young; carrying an average of 15 pups (Gomon et al. 2008).  Gestation period is ~1 year (Gomon et al. 2008).  Pups are born in summer at a size of 30‒35 cm TL (Rowling et al. 2010).  Females breed every second year. Growth  Maximum length of 175 cm TL (Gomon et al. 2008).  Longevity is 15 years (Pribac and Punt 2005). Diet  Feed on benthic and epibenthic prey, including crabs, lobsters, fishes and octopus (Simpfendorfer et al. 2001).

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King George Distribution,  Occur along the southern coastline of mainland Australia and the north coast of Tasmania (Kailola et movement al. 1993). whiting, and stock  Seagrass is important to newly settled larvae through protection from predators (Hindell et al. 2000) and the provision of food (Jenkins and Hamer 2001). Sillaginodes structure  From 5‒6 months, most fish are found on sand amongst vegetated habitats (Jenkins and Wheatley punctatus 1998).  In Port Phillip Bay, seagrass in the southern and western areas of the bay have been identified as critical habitat for the species (Morris and Ball 2006).  As King George whiting approach maturity (4‒5 years of age) they permanently leave Victorian bays and inlets and take up residence in open coastal waters (Jenkins 2005a).  King George whiting in spawning condition have rarely been recorded in Victorian waters (Hamer and Jenkins 2004). The only known significant spawning areas for the species are in South Australian waters (Fowler et al. 2000). The age and size of King George whiting have been shown to increase in a westerly direction along the Victorian coastline (Hamer and Jenkins 2004). Coupled with the absence of spawning activity in Victorian waters, this suggests that the species gradually migrates to the west towards South Australian waters to spawn (Hamer and Jenkins 2004).  Reverse modelling based on larval distributions suggests that most post‐larvae that enter Port Phillip Bay, Western Port and Corner Inlet‐Nooramunga are derived from a spawning area along the west coast of Victoria, but there is evidence for slight deviations for each bay and inlet (Jenkins et al. 2000). It has been suggested that the Corner Inlet‐Nooramunga fishery is replenished from a different spawning source than Port Phillip Bay and Western Port (Jenkins et al. 2000; Jenkins 2005b).  In South Australia, spawning occurs near coastal reefs in autumn/early winter (Fowler et al. 2000).  Spawning in coastal waters is followed by a protracted larval phase of 3‒5 months (Jenkins and May 1994; Fowler and Short 1996; Jenkins et al. 2000; Jenkins and King 2006).  Post‐larvae enter Victorian bays and inlets in spring (Jenkins and May 1994; Jenkins et al. 2000). Reproduction  Maturity is at 30‒35 cm (3‒5 years of age) (Scott 1954; Jones et al. 1990; Potter et al. 1996; Fowler and McGarvey 2000; Jenkins 2005a).  Spawns at least 20 times during the spawning season (Fowler et al. 1999; Fowler and McGarvey 2000).  In South Australia, individuals produce as many as 40,000 to 60,000 eggs per spawning event (Fowler et al. 1999), with an annual fecundity ranging from 112,000 to 6,000,000 eggs (Scott 1954; Fowler and McGarvey 2000).  Eggs are buoyant and hatch after a few days at a size of 2‒3 cm (Bruce 1995).  Spawning in South Australia has been observed when seawater temperatures are at 17‒19°C (Fowler et al. 1999). Growth  Maximum length is 72 cm TL (4.8 kg) (Gomon et al. 2008).  Longevity of 15 years. Diet  Juveniles feed on crustaceans; larger benthic organisms (including polychaete worms) dominate the diet of older fish. Silver Distribution  The distribution of silver trevally is not fully known due to past confusion with other species (P. dentex, P. wrighti, P. dinjera and Caranx nobilis), however, is thought to occur from southern New trevally, and movement South Wales to southern Western Australia, and New Zealand (Gomon et al. 2008). Pseudocaranx  Larvae have been observed entering Lake Macquarie in New South Wales from December to February (Miskiewicz 1987), in coastal waters off Sydney from August to May (Gray et al. 1992), off georgianus southern New South Wales in May and off northeast Tasmania in March (CMR, Hobart, unpublished data cited in (Bruce et al. 2002), and off Portland in Victoria in January (F. Neira AMC, Beauty Point, pers. comm. cited in (Bruce et al. 2002). Reproduction  In New South Wales, spawning occurs from spring to autumn (Rowling and Raines 2000).  Females in New South Wales mature at a length of 260‒280 mm at an age of 5‒6 years (Rowling and Raines 2000).  Fecundity is estimated at 220,000 eggs for a 370 mm female; fecundity in larger females is presumed to range up to 1,000,000 eggs (Rowling and Raines 2000). Growth  Maximum length of 80 cm TL (4.5 kg) (Gomon et al. 2008).  Slow growth rate.  Longevity of >20 years. Diet  Feeding occurs in both the benthic and pelagic environments, consuming more fish (by weight) than any other non‐fish dietary components (Bulman et al. 2001; Hindell 2006).

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Southern Distribution  Inshore squid species endemic to southern Australia, including Tasmania, and New Zealand and (Winstanley 1983). calamari, movement  Commonly in waters <70 m deep. Sepioteuthis  Individuals are capable of moving large distances (100s of kilometres) (Pecl and Moltschaniwskyj 2006). australis  Two genetically different populations exist in eastern and western Australia that is separated by a hybrid population in the intervening region (Triantafillos and Adams 2001).  In South Australia, small calamari (<30 mm DML) and large calamari (>150 mm DML) inhabit shallow, inshore waters; whereas small to medium sized calamari (30 mm to 150 mm) occupy offshore, deeper waters (Smith 1983; Triantafillos 2001). Reproduction  Size at first maturity ranges from 132 to 215 mm dorsal mantle length (DML) for females and 117 to 185 mm DML for males (Triantafillos and Adams 2001).  Visual surveys of egg masses suggest females spawn throughout the year (Moltschaniwskyj and Pecl 2007), in Tasmania, the majority of spawning occurs when mature calamari aggregate on the east coast during spring/early summer (Moltschaniwskyj and Pecl 2003).  In Victoria, anecdotal evidence suggests that spawning starts in late winter. Large calamari and egg masses have been observed in the Point Lonsdale Bight region.  Males deposit spermatophores in the female (Hanlon 1996).  Clusters of eggs have been observed attached to seagrass, macroalgae, sand and rocky substrate (Steer et al. 2005; Triantafillos and Adams 2001). Growth  Growth is rapid and the entire life cycle is completed in <1 year (Moltschaniwskyj and Pecl 2007; Steer et al. 2005).  Maximum recorded age for females and males is 263 and 291 days, respectively (Bradshaw 2005). Diet  Early life‐history feed on zooplankton and small crustaceans while adults feed on fish and squid. Southern sea Distribution  Occurs from Eden in southern New South Wales to Kalbarri in Western Australia, including and Tasmania (Kailola et al. 1993; Gomon et al. 2008). garfish, movement  Morphometric variation suggests there are two distinct stocks in South Australia and Western Hyporhamphus Australia (Collette 1974).  Found in shallow (<20 m deep) inshore waters, in the pelagic environment primarily over seagrass melanochir (Kailola et al. 1993; McGarvey et al. 2006; Gomon et al. 2008). Reproduction  Spawns inshore during late spring/summer (Ling 1958; Jones 1990)  Sex‐specific schools form.  Matures at ~20 cm SL (Ye et al. 2002).  Batch fecundity is relatively low (Ye et al. 2002).  Eggs are large (2.5‒3 mm in diameter) relative to body size, and have adhesive filaments that are used to attaché to filamentous algae (Mills et al. 1997) and seagrass (Ling 1958). Growth  Maximum length is 50 cm FL (Collette 1974).  Fast growth rate.  Mean size at one year is 160‒185 mm TL (Victoria, South Australia and Western Australia (Ye et al. 2002).  Growth slows considerably once individuals attain ~270 mm TL (Ye et al. 2002).  Protracted spawning season results in a high degree of size variation at age (Ye et al. 2002).  Longevity is 10 years (Jones 1990). Diet  Consumes seagrass, epiphytic algae and invertebrates (Klumpp and Nicholas 1983; Robertson and Klumpp 1983; Earl 2007). Rock Distribution  Occurs from southern Queensland to southern Western Australia, including Tasmania (Gomon et al. 2008). flathead,  Found in a range of habitats, often seagrass, to a depth of 20 m (Gomon et al. 2008; Kuiter 2000). Platycephalus  Forms sex‐specific aggregations (Koopman 2002). Reproduction  Spawn from September to February, with maximum spawning effort observed in October (Koopman laevigatus 2002). Growth  Maximum length of 50 cm SL (Gomon et al. 2008).  Growth is highly variable.  Females and males from Corner Inlet‐Nooramunga attain an average size of 39 and 34 cm TL, respectively, at 5 years of age, and 48 and 40 cm TL at 10 years, respectively (Koopman 2002). Diet  Smaller rock flathead (25‒33 cm TL) consume mainly fish, squid and shrimp, whilst larger fish (>33 cm TL) consume particular crab species and some fish (Klumpp and Nichols 1983).  In Port Phillip Bay, 50% of the base nutrition is from food webs supported by seagrass (Hindell 2006).

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Seagrass in Corner Inlet

Seagrass habitat is considered crucial for was located in shallower water compared to P. fisheries production in Corner Inlet, as seagrass australis, and was positively associated with is the basis of the trophic food web for distance into inlet (O’Hara et al. 2002). important commercial and recreational fisheries Aerial photographs and ground‐truthing, using species like King George whiting, rock flathead video cameras and core samples, are a common and southern sea garfish (Hindell et al. 2007). means of monitoring changes in seagrass cover There are four species of seagrass in Corner in Victoria (Warry and Hindell 2009). In Corner Inlet: two narrow leafed eel seagrasses Inlet, a 29‐year historical record of aerial (Heterzostera nigricaulis, Zostera muelleri), photographs found temporal changes in southern paddleweed, which has small oval seagrass cover, particularly in the northern and leaves (Halophilia australis), and one broad north‐west regions of Corner Inlet (Roob et al. leafed, medium‐dense seagrass (Posidonia 1998). Zostera muelleri and H. nigricaulis were australis) (Roob et al. 1998). The location of the considered as one species, Zostera sp., as they seagrass species varies within Corner Inlet, with cannot be differentiated using remote sensing. H. nigricaulis located in the subtidal zone up to Total seagrass cover in Corner Inlet in 1998 was 3−4 m, Z. muelleri located in the intertidal flats, 124 km2, composed of 69% Zostera sp., 25% P. H. australis in deeper waters >2‐3m, and P. australis, and the remainder H. australis growing australis located in the shallow sub‐tidal zone in between the other species (Roob et al. 1998). (Ball et al. 2010). Posidonia australis is of particular interest as Corner Inlet is its only Using Roob et al. (1998) as a baseline study, Victorian location (Ball et al. 2010). Posidonia remote monitoring of seagrass cover in Corner australis is a key‐stone species that provides food Inlet has continued in the 2000’s. From 2005‐ and shelter for both vertebrates and 2006, 6 sites were monitored (3 sites in the north‐ invertebrates and provides structure in mudflat west where there is high seagrass loss and 3 sites areas (O’Hara et al. 2002). Posidonia australis is in south and east where P. australis is doing slow growing as it spreads via rhizomes rather well) (Hindell et al. 2009). All study sites than seedlings, and re‐colonisation of P. australis showed a decline in seagrass area between 1998 is thought to take decades, if at all (e.g. Kirkman and 2006, with higher losses in the north, and a and Kuo 1990). total decline of >50%. Seagrass loss varied between sites, with loss of 10−34% in the south Since the 1960s, there has been sporadic and east, 91% loss of P. australis in the northern monitoring of seagrass cover in Corner Inlet. In sites, and no seagrass loss at Granite Island 1965, there was estimated 11 900 ha of P. (Hindell et al. 2009; Ball et al. 2010). Structural australis, Z. muelleri and H. nigricaulis in Corner attributes of seagrass also indicate evidence of Inlet (Morgan 1986). Unquantified reports of broad‐scale seagrass decline (Hindell et al. 2009). decline in seagrass cover was reported from However, there was a recovery in seagrass cover 1965‐78, and there was also a decrease in fishers at these same sites from 2006‐2007 (Ball et al. in Corner Inlet in the same time period (Poore 2010). Seagrass cover remains less than in 1998, 1978). No cause was attributed to the decline in with up to 45% less cover in the northern seagrass cover, although human activity was regions of Corner Inlet (Ball et al. 2010). The implied to have had a detrimental impact (Poore recovery in seagrass cover is most likely due to 1978). In 2000, southern Corner Inlet was the spread of Zostera sp. rather than recovery of surveyed using transects, with a specific focus P. australis, due its slow growth (Ball et al. 2010). on P. australis beds (O’Hara et al. 2002). This study found a notable seasonal change in P. Aerial and satellite images used for mapping australis height and cover, and evidence of haul coastal areas have recently been augmented by seining net damage, which resulted in reduced remotely‐sensed bathymetric datasets, for height, cover, and faunal abundance in P. example LiDAR (Light Detection and Ranging), australis beds (O’Hara et al. 2002). P. australis which atmospherically corrects the satellite was found to dominate banks with low tides of images (Monk et al. 2011). In 2011, ALOS 0.5‐4m and was negatively associated with (Advanced Land Observation Satellite) was distance into the inlet (O’Hara et al. 2002). H. used to map seagrass cover in the north‐west nigricaulis did not show any seasonal change, section of Corner Inlet. P. australis was

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constrained to 2.5 m depth on sand banks, while Seagrass cover in Corner Inlet has been variable Zostera sp. was confined to 6.5 m on mud and over the past 50 years. From recent surveys, sand flats close to shore (Monk et al. 2011). P. seagrass has declined up to 91%, especially in australis cover was 22% (4608 ha) of the site, the northern sites, from 1998−2006. P. australis while Zostera sp. was 20% (4229 ha), and bare loss is higher than Zostera sp., which is probably sand and mud dominated >50 % of the site due to P. australis having slow re‐colonisation. (Monk et al. 2011). Compared to 1998, 39% of the In 2007, there was a recovery of seagrass cover, seagrass habitat has remained stable, and but northern areas still had 45% less cover than seagrass cover had a net gain (39% gain, 25% in 1998. The recovery of seagrass cover is loss) since 1998 (Monk et al. 2011). The gains thought to be due to the spread of Zostera sp. were observed in the littoral zones, while the into bare sand areas, rather than a recovery of P. losses were across the tops of sandbanks further australis. Mapping of seagrass cover in 2011 into the inlet (Monk et al. 2011). Furthermore, found that 39% of the seagrass habitat was when specific seagrass species were considered, stable since 1998, while overall seagrass had a Zostera sp. had a net gain while P. australis cover net gain, which was driven by Zostera sp. had a net loss (Monk et al. 2011). However, there Several projects are addressing and reducing is a time lag between the satellite image used in sediment and nutrient loads into Corner Inlet this mapping (2009) and ground‐truthing of the (coordinated by WGCMA): image (2011), so temporal changes in seagrass cover may have occurred that are not  Erosion control by fencing to keep stock out documented. However, the extent of change in of creeks, revegetation of rivers, creeks and seagrass cover since the 1998 study suggests drains long‐term temporal change rather than shorter  term seasonal changes in seagrass cover in Whole farm planning workshops Corner Inlet (Monk et al. 2011).  Control programs for gully, hill slope and The cause of decline in P. australis is unknown, drainage erosion issues but there may be a link to turbidity as areas with  Improving effluent and fertilizer high turbidity had high losses of medium‐dense management on farms seagrass beds (Hindell et al. 2009). Turbidity can  block photosynthesis and increase Continued monitoring of water quality sedimentation on banks resulting in increased (EPA/WGCMA). exposure of seagrass beds to desiccation during Monitoring of seagrass in Corner Inlet continues low tide. Other potential factors that may to track the success of investment in improving influence seagrass loss include mechanical the health of Corner Inlet (Deakin University, damage from boat propellers and/or haul seines, University of Tasmania, Parks Victoria and the water quality and nutrients levels, introduction WGCMA). of marine pests, and alteration of hydrodynamic regimes (Warry and Hindell 2009). In a previous study, water quality was found to be fair and metal concentrations were low in Corner Inlet, although nutrient levels were higher than those recommended by the EPA (Hindell et al. 2009).

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Acknowledgements

Thank you to the following people for their  The commercial and recreational fishers that contributions: provided responses to local knowledge surveys. Their insight was invaluable and  The Catch and Effort Unit for processing the very much appreciated commercial fishery data; Paula Baker, Ursula Koliba and Monique Nellis  The people who participated and provided information at the Corner Inlet Stock  Neville Clarke, Ken Avery, Matthew Assessment Workshop held in Welshpool, Goulden, Fosters Seafoods, Wayne and Victoria, June 2012. Their assistance in the Linda Cripps for assisting in the provision development and review of this assessment of commercial catch samples is gratefully acknowledged.  Pam Oliveiro, Katrina Halse, Tina Whillock  Ross Winstanley for chairing the 2012 and Pieta Lindberg for recreational data assessment workshop. entry and editing  Travis Dowling, Leanne Gunthorpe, James  Pam Oliveiro for extracting otoliths to Andrews and Terry Walker for providing facilitate fish age determination comments on this report.  Corey Green for generating fish ageing data

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References

Ball, D., Parry, G.D., Heislers, S., Blake, S., Estuaries Assessment Framework for Non‐ Werner, G., Young, P., Coots, A. (2010). Pristine Estuaries. Estuary 613 (Corner Inlet). Victorian multi‐regional seagrass health Fowler, A.J., Black, K.P., Jenkins. G.P. (2000). assessment 2004‐07. Fisheries Victoria Determination of spawning areas and larval Technical Report No. 66, 105 pages, advection pathways for King George whiting Department of Primary Industries Victoria, in southeastern Australia using otolith Queenscliff, Victoria, Australia. microstructure and hydrodynamic modelling. Bradshaw, M.B. (2005). Options for the longer‐ II. South Australia. Marine Ecology Progress term management of southern calamari. Series 199, 243‐254. Department of Primary Industries Water and Fowler, A.J., McGarvey, R. (2000). Development Environment Hobart, 1–17. of an integrated fisheries management model Bruce, B.D. (1995). Larval development of King for King George whiting (Sillaginodes punctata) George whiting, Sillaginodes punctata, school in South Australia, Final report to FRDC for whiting, Sillago bassensis, and yellow fin project 95/008. whiting, Sillago schomburgkii (Percoidei: Fowler, A.J., McLeay, L., Short, D.A. (1999). Sillaginidae), from South Australian waters. Reproductive mode and spawning Fishery Bulletin 93, 27‐43. information based on gonad analysis for the Bruce, B.D., Bradford, R., Daley, R., Green, M., King George whiting (Percoidei: Sillaginidae) Phillips, K. (2002). Targeted review of from South Australia. Marine and Freshwater biological and ecological information from Research 50, 1‐14. fisheries research in the south east marine Fowler, A.J., Short, D.A. (1996). Temporal region. CSIRO Marine Research, Hobart. variation in the early life‐history Bulman, C., Althaus, F., He, X., Bax, N.J., characteristics of the King George whiting Williams, A. (2001). Diets and trophic guilds (Sillaginodes punctata) from analysis of otolith of demersal fishes of the south eastern microstructure. Marine and Freshwater Australian shelf. Marine and Freshwater Research 47, 809‐818. Research 52, 537‐548. Gomon, M., Bray, D., Kuiter, R. (2008). Fishes of Collette, B.B. (1974). The garfishes Australiaʹs southern coast. Sydney: Reed New (Hemiramphidae ) of Australia and New Holland. Zealand. Recordings of the Australian Gray, C.A., Otway, N.M., Laurenson, F.A., Museum 29, 11–1105. Miskiewicz, A.G., Pethebridge, R.L. (1992). Crawford, C.M. (1984). An ecological study of Distribution and abundance of marine fish Tasmanian flounder. PhD Thesis. University larvae in relation to effluent plumes from of Tasmaina. sewage outfalls and depth of water. Marine Biology 113, 549‐559. Earl, J. (2007). Feeding biology of southern sea garfish (Hyporhampus melanochir, Hanlon, R., Messenger, J.B. (1996). Cephalopod Hemiramphidae) in Gulf St. Vincent, South behaviour. Cambridge University Press, Australia. Honours Thesis, School of United Kingdom. Biological Sciences, Flinders University, South Hamer, P.A., Jenkins, G.P. (2004). Identifying the Australia. spawning locations of King George whiting in Edgar, G.J., Shaw, C. (1995). The production and Victorian waters: a recreational fishing based trophic ecology of shallow water fish study, Marine and Freshwater Resources assemblages in southern Australia. 1. Species Institute, Queenscliff. richness, size structure and production of Henry, G.W. and Lyle, J.M. (2003) The national fishes in Western Port, Victoria. Journal of recreational and indigenous fishing survey. Experimental Marine Biology and Ecology New South Wales Fisheries, NSW Fisheries 194, 53‐81. Final Report Series No. 48, Sydney.

Corner Inlet‐Nooramunga Fishery Assessment 2012

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Hindell, J.S. (2006). Assessing the trophic link I. Victoria. Marine Ecology Progress Series between seagrass habitats and piscivorous 199, 231‐242. fishes. Marine and Freshwater Research 57, Jenkins, G.P., Hamer, P.A. (2001). Spatial 121‐131. variation in the use of seagrass and Hindell, J.S., Jenkins, G.P., Keough, M.J. (2000). unvegetated habitats by post‐settlement King Evaluating the impact of predation by fish on George whiting (Percoidei: Sillaginidae) in the assemblage structure of fishes associated relation to meiofaunal distribution and with seagrass (Heterozostera tasmanica) macrophyte structure. Marine Ecology‐ (Martens ex Ascheron) den Hartog, and Progress Series 224, 219‐229. unvegetated sand habitats. Journal of Jenkins, G.P., May, H.M.A. (1994). Variation in Experimental Marine Biology and Ecology settlement and larval duration of King George 255, 153–174. whiting, Sillaginodes punctata (Sillaginidae), in Hindell, J.S., Jenkins, G.P., Keough, M.J. (2000). Swan Bay, Victoria, Australia. Bulletin of Variability in abundances of fishes associated Marine Science 54, 281‐296. with seagrass habitats in relation to diets of Jenkins, G.P., May, H.M.A., Wheatley, M.J., predatory fishes. Marine Biology 136, 725‐737. Holloway, M.G. (1997). Comparison of fish Hindell, J., Ball, D., Brady, B., Hatton, D. (2007). assemblages associated with seagrass and Establishment of a monitoring program to adjacent unvegetated habitats of Port Phillip assess estuarine water quality and its effects Bay and Corner Inlet, Victoria, Australia, with on seagrass health in Corner Inlet. Department emphasis on commercial species. Estuarine of Primary Industries, Queenscliff, Victoria. Coastal and Shelf Science 44, 569–588. Hindell, J., Ball, D., Brady, B., Hatton, D. (2009). Jenkins, G.P., Shaw, M., Stewart, B.D. (1993). Assessment of estuarine water quality and its Spatial variation in food‐limited growth of effects on seagrass health in Corner Inlet. juvenile Greenback Flounder, Rhombosolea Fisheries Victoria Technical Report No. 46, 42 tapirina: Evidence from otolith daily pp. Department of Primary Industries, increments and otolith scaling. Canadian Queenscliff, Victoria, Australia. Journal of Fisheries and Aquatic Science 50, 2558–2567. Hoedt, F.E., Dimmlich, W.F. (1994). Diet of subadult Australian salmon, Arripis truttaceus, Jenkins, G.P., Wheatley, M.J. (1998). The in Western Port, Victoria. Australian Journal influence of habitat structure on nearshore fish of Marine and Freshwater Research 45, 617‐ assemblages in a southern Australian 623. embayment: comparison of shallow seagrass, reef algal, and unvegetated habitats, with Jenkins, G.P., King, D. (2006). Variation in larval emphasis on their importance to recruitment. growth can predict the recruitment of a Journal of Experimental Marine Biology and temperate seagrass‐associated fish. Oecologia Ecology 221, 147‐172. 147, 641–649. Jones, G.K. (1990). Growth and mortality in a Jenkins, G.P. (2005a). The influence of climate on lightly fished population of garfish the fishery recruitment of a temperate, (Hyporhampus melanochir) in Baird Bay, South seagrass associated fish, the King George Australia. Transactions of the Royal Society of whiting, Sillaginodes punctata. Marine Ecology‐ South Australia 114, 37–45. Progress Series 288, 263‐271. Jones, G.K., Hall, D.A., Hill, K.L., Standiford, Jenkins, G.P. (2005b). The influence of climate on A.J. (1990). The South Australian Marine the fishery recruitment of a temperate, Scalefish Fishery, South Australian seagrass associated fish, the King George Department of Fisheries. whiting, Sillaginodes punctata. Marine Ecology Progress Series 288, 263‐271. Kailola, P.J., Williams, M.J., Stuart, P.C., Reichelt, R.E., McNee, A., Grieve, C. (Eds) Jenkins, G.P., Black, K.P., Hamer, P.A. (2000). (1993) Australian Fisheries Resources, Bureau Determination of spawning areas and larval of Rural Resources, Department of Primary advection pathways for King George whiting Industry and Energy, and the Fisheries in southeastern Australia using otolith Research and Development Corporation, microstructure and hydrodynamic modelling. Canberra.

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Kent, J., Gunthrope, L., Werner, G. (Eds.) (2011). melanochir. The Australian Society for Fish Corner Inlet Fish Habitats 2007. Compiled by Biology and the Fish and Aquatic Resource the Fish Habitat Assessment Group. Fisheries Management Association of Australasia Victoria Assessment Report Series. Report No. Conference Proceedings, Darwin. 66. 27 pp. (Fisheries Research Branch, Miskiewicz, A.G. (1987). Taxonomy and ecology Queenscliff). of fish larvae in Lake Macquarie and New Kent, J., Kemp, J., Bruce, T., Conron, S., Brown, South Wales coastal waters, PhD thesis, L., Bridge, N., MacDonald, C.M., Ryan, K.L. University of New South Wales. (2012). Corner Inlet and Nooramunga fishery Moltschaniwskyj NA, Pecl GT (2003) Small‐scale assessment 2008. Fisheries Victoria Internal spatial and temporal patterns of egg Report Series No. 8. production by the temperate loliginid squid Kirkman H., and Kuo, J. (1990). Pattern and Sepioteuthis australis. Marine Biology 142, process in south western Australian 509‐516. seagrasses. Aquatic Botany 21, 363‐375. Moltschaniwskyj, N.A., Pecl, G.T. (2007). Klumpp, D.W., Nichols, P.D. (1983). A study of Spawning aggregations of squid (Sepioteuthis food chains in seagrass communities II.* Food australis) populations: A continuum of of the rock flathead, Platycephalus laevigatus ʹmicrocohortsʹ. Reviews in Fish Biology and Cuvier, a major predator in a Posidonia Fisheries 17, 183‐195. australis seagrass bed. Australian Journal of Monk, J. Pope, A. Ierodiaconou, D. Otera, K. Marine and Freshwater Research 34, 745–754. Mount, R. (2011). Corner Inlet and Koopman, M. (2002). The life and times of rock Nooramunga habitat mapping project. Deakin flathead under investigation. Information University, Warrnambool, Victoria, Australia. Note 0529, Marine and Freshwater Resources 60 pp. Institute, Victoria. Morgan G. J. (1986). A survey of macrobenthos Kuiter, R.H. (2000). Coastal Fishes of South‐ in the waters of Corner Inlet and Eastern Australia. Gary Allen Pty Ltd, Nooramunga, with an assessment of the Smithfield, NSW. extent of Posidonia seagrass. Fisheries and Wildlife (Victoria) Paper, no. 31, 49 pp. Ling, J.K. (1958). The sea garfish, Reporhampus melanochir (Cuvier and Valenciennes) Morison, A.K., Robertson, S.G., Smith, D. (1998). (Hemiramphidae), in South Australia: An integrated system for production fish breeding, age determination, and growth rate. ageing: image analysis and quality assurance. Australian Journal of Marine and Freshwater North American Journal of Fisheries Research 9, 60–105. Management 17, 587‒598. MacDonald, C.M. (Ed.) (1997). Corner Inlet‐ Morris, L., Ball, D. (2006) Habitat suitability Nooramunga fin fisheries ‐ 1994. Compiled by modelling of economically important fish the Bay and Inlet Fisheries and Stock species with commercial fisheries data. ICES Assessment Group. Fisheries Victoria Journal of Marine Science 63, 1590‐1603. Assessment Report No. 3. Fisheries Victoria, O’Hara, T. D., Norman, M. D., Staples, D. A. East Melbourne. (2002). Baseline monitoring of Posidonia McGarvey, R., Feenstra, J.E., Fowler, A.J., seagrass beds in Corner Inlet, Victoria. Jackson, W.B. (2006). Garfish (Hyporhamphus Museum Victoria Science Reports 1: 1‐44. melanochir) fishery. Fishery Assessment Report Pecl, G.T., Moltschaniwskyj, N.A. (2006) Life to Primary Industries and Resources South history of a short‐lived squid (Sepioteuthis Australia for the Marine and Scalefish Fishery australis): resource allocation as a function of Management Committee. South Australian size growth maturation and hatching season Research and Development Institute (Aquatic ICES Journal of Marine Science 63, 995–1004. Sciences), Adelaide, SARDI Research Report Series No. 163. Poore, G. C. B. (1978). The decline of Posidonia australis in Corner Inlet. Marine Studies Mills, D., Jordan, A., Ewing, G. (1997). Group, Ministry for Conservation, Preliminary findings on spawning Environmental Studies Program Project distribution, egg and larval development in Report no. 228, 28 pp. the southern sea garfish Hyporhamphus

Corner Inlet‐Nooramunga Fishery Assessment 2012

43

Potter, I.C., Hyndes, G.A., Platell, M.E., Sarre, limitation of juvenile flounder Rhombosolea G.A., Valesini, F.J., Young, G.C., Tiivel, D.J. tapirina Günther. Journal of Experimental (1996). Biological data for the management of Biology and Ecology 165, 1–21. competing commercial and recreational Simpfendorfer, C.A., Goodreid, A., Mcauley, fisheries for King George whiting and black R.B. (2001). Diet of three commercially bream, Fisheries Research and Development important shark species from Western Corporation, FRDC Project 93/82, School of Australian waters. Marine and Freshwater Biological and Environmental Sciences, Research 52, 975–985. Murdoch University, Western Australia. Smith, H.K. (1983). The development potential Pribac, F., Punt, A.E. (2005). Using length, age of the southern calamary. South Australia and tagging data in a stock assessment of a Department of Fisheries, Adelaide. length selective fishery for gummy shark (Mustelus antarcticus). Journal of Northwest Steer, M.A., Fowler, A.J., Jackson, W.B., Atlantic Fishery Science 35, 267–290. Jennings, P.R. (2005) Southern calamary (Sepioteuthis australis) fishery. SARDI Aquatic Robertson, A.I., Klumpp, D.W. (1983). Feeding Sciences Publication No. RD05/0006. habits of the Southern Australian Garfish Hyporhamphus melanochir: A diurnal herbivore Triantafillos, L. (2001). Population biology of and nocturnal carnivore. Marine Ecology‐ southern calamary, Sepioteuthis australis, in Progress Series 10, 197–201. Gulf St Vincent, South Australia. PhD dissertation, Northern Territory University, Roob, R., Morris, P., Werner, G. (1998). Victorian Darwin. marine habitat database: Corner Inlet‐ Nooramunga seagrass mapping. Marine and Triantafillos, L., Adams, M. (2001) Allozyme Freshwater Resources Institute, Queenscliff, analysis reveals a complex population Victoria. 71 pp. structure in the southern calamary Sepioteuthis australis from Australia and New Zealand. Rowling, K.A., Hegarty, A., Ives, M. (Eds) Marine Ecology‐ Progress Series 212, 193 –209. (2010). Status of Fisheries Resources in New South Wales, 2008/09. Industry and Warry, F. Y. and Hindell, J. S. (2009) Review of Investment NSW, Cronulla, 392 pp. Victorian seagrass research, with emphasis on Port Phillip Bay. Arthur Rylah Institute for Rowling, K.R., Raines, L.P. (2000). Description of Environmental Research. Draft Report. the biology and an assessment of the fishery of Department of Sustainability and silver trevally (Pseudocaranx dentex) off New Environment, Heidelberg, Victoria. South Wales, NSW Fisheries Final Report No. 24. Winstanley R.H. (1983) Australian celphalopod resources Memoirs of the Natural Museum of Ryan, K.L., Morison, A.K. and Conron S. (2009) Victoria 44, 243–253 Evaluating methods of obtaining total catch estimates for individual Victorian bay and Ye, Q., Noell, C., McGlennon, D. (2002). inlet recreational fisheries. Department of Reproductive biology of sea garfish. In Primary Industries, FRDC Final Report No Fisheries Biology and habitat ecology of 2003/047, Queenscliff southern sea garfish (Hyporhamphus melanochir) in southern Australian waters Scott, T.D. (1954). The life history of the spotted Jones, G.K., Ye, Q., Ayvasian, S. and Coutin, P. whiting, Sillaginodes punctatus (Cuv. and Val.) (eds), pp. 35–99. Fisheries Research and in South Australia, Masters Thesis, Univeristy Development Corporation Project 97/133, of Adelaide. Canberra, Australia. Shaw, M., Jenkins, G.P. (1992). Spatial variation in feeding, prey distribution and food

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