Fish habitat vulnerability mapping in coastal …...Fish habitat vulnerability mapping in coastal Queensland Moreton Bay region vii The audit has been applied to approximately one

Dep

artm

ent o

f Ag

ricu

ltu

re, F

ish

erie

s an

d F

ore

stry

F

ishe

ries

Qu

eens

land

Fish habitat vulnerability mapping incoastal Queensland

Report 1: Moreton Bay region

Fish habitat vulnerability mapping

in coastal Queensland

Report 1: Moreton Bay Region

Deception Bay, South East Queensland

Fish habitat vulnerability mapping in coastal Queensland Moreton Bay region

ii

Fish habitat vulnerability mapping in coastal Queensland Report 1: Moreton Bay Region John Beumer 1 David Sully 1 and Dawn Couchman 2 1. Department of National Parks, Recreation, Sport and Racing 2. Department of Agriculture, Fisheries and Forestry July 2012 Please cite this report as: Beumer, J P, Sully, DW and Couchman, D, 2012. Fish Habitat Vulnerability Mapping in Coastal Queensland. Report 1: Moreton Bay Region. Queensland Government, 61pp. For complete project results please also read the following report: Fish habitat vulnerability mapping in coastal Queensland Report 2: Townsville Region © State of Queensland, 2012.

The Queensland Government supports and encourages the dissemination and exchange of its information. The

copyright in this publication is licensed under a Creative Commons Attribution 3.0 Australia (CC BY) licence.

Under this licence you are free, without having to seek permission from DAFF, to use this publication in accordance

with the licence terms.

You must keep intact the copyright notice and attribute the State of Queensland, Department of Agriculture, Fisheries

and Forestry as the source of the publication.

For more information on this licence visit http://creativecommons.org/licenses/by/3.0/au/deed.en


iii

http://creativecommons.org/licenses/by/3.0/au/deed.en

Contents Executive summary vi

1. Introduction 1

1.2 Project outline 2 2. Methods 3

2.1 Mapping 3 2.2 Modelling 5 2.3 Communication 7 3. Study area 7

3.1 Fish habitat diversity 8 3.2 Wild-harvest fisheries 9 3.4 Site description 12 3.3 Historic marine plant mapping for Moreton Bay 13 4. Results 13

4.1 Model 1 results 14 4.2 Model 2 results 15 4.3 Model 3 results 15 4.4 Project status 16 4.4.1 Fish habitat vulnerability 16 4.4.2 Queensland Herbarium 17 4.5 Implications of audits 17 5. Adaptation to SLR risk 18

5.1 Issue identification for stakeholders 19 5.1.1 Local government 19 5.1.2 Fishing industry 21 5.2 Regional context 22 5.3 Case study – Moreton Bay Tunnel Net fishery 22 6. Stakeholder consultation 23

7. Related habitat vulnerability projects 26

7.1 University of Queensland SLR modelling project 26 7.2 Queensland Herbarium project 27 References 29

Appendix 1: Model 2 - Maps depicting the current and future extent of marine plants (mangroves and saltmarsh) for each site 32

Appendix 2 Fish habitat vulnerability matrix [2010] 41

Impact table 41 Adaptation table 43 Risk statement 45 Way forward 45 Appendix 3 SLAMM Model 3 project summary & map outputs 46


iv

List of tables Figure 1 Conceptual diagram showing the distribution within the marine plant zone 2 Figure 2 MSL, HAT, LiDAR contours and sea level rise scenarios 4 Figure 3 Tidal profile (Adapted from the OzCoasts website, Geoscience Australia). 5 Figure 4 Model 1 – Marine plant zone reduced as sea level rises; losses only. 5 Figure 5 Model 2 – Marine plant zone shifts landward as new areas colonised with SLR. 6 Figure 6 Model 3 – Marine plant zone shifts landward and seaward with SLR. 6 Figure 7 Mangrove zonation (adapted from NSW DPI Mangrove Primefact, 2008). 8 Table 1 Summary of wild-harvest fisheries operating in or near Moreton Bay 9 Figure 8 Location of the 8 Moreton Bay study sites, showing CFish reporting grids. 11 Table 2 summary information for all Moreton Bay sites 12 Table 3 Extent of marine plant groups per LGA (based on Dowling & Stevens 1998) 13 Table 4 Model 1 audit summary 14 Table 5 Model 2 audit summary 15 Table 6 Model 3 audit summary 16 Figure 9. Loss of fish habitats due to ‘coastal squeeze’ adapted from DCC 2009 report. 19 Figure 10. Projected loss of mangrove and seagrass habitats in Pacific Island countries and territories 22 Figure 11. A tunnel net is set along a mangrove shoreline in Moreton Bay (Photo by Chris Calogeras, C-AID Consultants) 23 Table 7 Local government consultation 24 Table 8 Consultation activities with industry, research organisations and national bodies 25 Table 9 SLAMM adapted vegetation and wetland types (19 categories) and zones 27 List of Figures Figure 1 Conceptual diagram showing the distribution within the marine plant zone 2 Figure 2 MSL, HAT, LiDAR contours and sea level rise scenarios 4 Figure 3 Tidal profile (Adapted from the OzCoasts website, Geoscience Australia) 5 Figure 4 Model 1 – Marine plant zone reduced as sea level rises; losses only 5 Figure 5 Model 2 – Marine plant zone shifts landward as new areas colonised with SLR 6 Figure 6 Model 3 – Marine plant zone shifts landward and seaward with SLR 6 Figure 7 Mangrove zonation (adapted from NSW mangrove Primenote, 2008) 8 Figure 8 Location of the 8 Moreton Bay study sites, showing CFish reporting grids. 11 Figure 9 Loss of fish habitats due to ‘coastal squeeze’ adapted from DCC 2009 report. 19 Figure 10 Projected loss of mangrove and seagrass habitats in Pacific Island countries and territories 22 Figure 11 A tunnel net is set along a mangrove shoreline in Moreton Bay (Photo by Chris Calogeras, C-AID Consultants) 23


v

Executive summary Healthy fish habitats support important socio-economic activities associated with recreational, commercial and indigenous fisheries along coastal Queensland. Predicted sea level rise (SLR) as a result of accelerated climate variation will have ongoing impacts on the fisheries productivity of these habitats. Fisheries Queensland has undertaken a project which audited and mapped the vulnerability of marine vegetation communities (fish habitats) to the physical impacts of SLR. A key project objective was the incorporation of the audits within local government planning schemes to identify and establish adaptation strategies, i.e. retreat areas, to facilitate agreed landward migration of these important fish habitats. The project has mapped the vulnerability of fish habitats in two regions in east coast Queensland, Moreton Bay and Townsville, with eight sites in Moreton Bay and four sites in Townsville, mapped under four sea level rise (SLR) scenarios. Scenarios are based on current base-line distributions of marine vegetation (0 cm) and low (25 cm), medium (75 cm) and high (100 cm) SLR predictions. The 75cm scenario is indicative of the 80 cm SLR of the Queensland Coastal Plan 2012. The methodology for high resolution mapping of changes in fish habitat due to sea level rise was developed in Moreton Bay and is being applied to (and tested on) Townsville. It will be available for local governments who can apply it to other regions to accommodate shifts in marine plant communities. Within the Moreton Bay region, the eight sites encompass four local government areas from south to north: Gold Coast City Council, Redland City Council, Brisbane City Council and Moreton Bay Regional Council. Each local government has been consulted during the identification and mapping of the sites. Fisheries Queensland is currently undertaking further consultation with Councils to identify the process for transferring the audit information and mapping into Council Graphical Information Systems (GIS) and planning schemes and development assessment systems and providing the methodology to allow Councils to complete the audit for the balance of its Moreton bay foreshores. For the Moreton Bay region, Models 1,2 and 3 have been applied; and for the Townsville region, Models 1 and 2 have been applied. The three models are:

Model 1 – Constrained. Losses only with SLR. No ability for marine plants to move by landward colonisation due to either natural or human barriers or rate of SLR is too fast for marine plants to adapt to.

Model 2 – Unconstrained. Losses and gains. Marine plants are able to move by landward colonisation with SLR where contours allow.

Model 3 – Unconstrained (losses and gains assuming marine plants can colonise landward and seaward, based on the Sea Level Affecting Marshes Model (SLAMM)).

In summary, the audits indicate an overall 95% loss of marine fish habitats across the 8 sites for Model 1. A gain of 10% for Model 2 and a gain of 67% for Model 3 at the 100 cm SLR scenario. All Models show a marked difference in mangrove community extent between the southern and northern parts of Moreton Bay, with the gains in fish habitats occurring mostly on the undeveloped floodplains of the estuaries of the Caboolture River region.


vi


vii

The audit has been applied to approximately one third of the current (Dowling, 1998) Moreton Bay distribution of marine plant communities. The vulnerability project integrates fisheries catch data to inform indicator species, e.g. banana prawns and mud crabs, and effort shifts and adaptation options for the fishing industry within each region. In a related project, the Queensland Herbarium is establishing benchmarks and mapping mangroves and associated marine plant communities at 20 sites in Moreton Bay. The project will document past and ongoing changes based on over 70 years of information and mangrove community diversity changes long-term.

1. Introduction Marine fisheries rely heavily on healthy intertidal habitats and projected SLR, increasing ocean acidity, temperatures and alterations to runoff, as a result of climate variation, will have significant impacts on these fish habitats. Mapping predicted changes from these impacts will enable local governments to incorporate the anticipated habitat changes into planning schemes (e.g. vegetated buffers and retreat areas), to maintain optimal fish habitat diversity for local and regional fisheries. The reported SLR of 7 mm per year since 1993 for Papua New Guinea (PCCSP 2011) confirms the urgency of a better understanding of the effects of SLR on marine plant communities. Queensland, as a leader in the field of marine plant and related tidal habitat management is looking to better understand the impacts of climate variability and change on fish habitats and dependent fisheries resources. There has been a limited focus on marine ecosystem climate variation related research on marine ecosystems compared to research that has been conducted on terrestrial ecosystems. Fish and crab species targeted by commercial and recreational fishing depend on connected tidal wetlands for fisheries production to support catches (Meynecke et al 2008). Without adaptation such as strategic planning to accommodate shifts in habitats, climate change will have significant impacts on fish production, catch composition, coastal fishing, coastal communities and associated socio-economic benefits in Queensland. The project delivers in part the recommendation in the Climate Change and the Great Barrier Reef: A Vulnerability Assessment (Johnson and Marshall, eds., 2007) Report, for more detailed information on the effects of SLR on mangroves and other tidal fish habitats to enable greater ability to predict future consequences of climate change impacts to coastal communities and the fishing industry. One of the management responses recommended in Chapter 9 of the Report - vulnerability of mangroves and associated tidal habitats to climate change - is specifically addressed:

“1. Quantitative assessment of lands that will become intertidal by 2080. Digital elevation models of estuaries are needed to augment and improve the OzEstuaries (now OzCoasts) database.”

The need for systematic mapping of mangroves, seagrasses and intertidal flats, including habitat area, plant density and species composition, is also a research priority in the recently released report: Vulnerability of Tropical Pacific Fisheries to Climate Change (Bell, Johnson and Hobday, editors, 2011). This report also noted that there is a need to provide information and mapping at locally relevant scales to better enable managers to identify the fish habitats most at risk so as to focus management efforts. The project is linked to the Fisheries Queensland Strategy and the Northern Tropical Australia Program for adaptation of fishing and aquaculture sectors to climate change. Information from the project will lead to enhanced strategic planning for coastal development and better informed decisions for climate change adaptation strategies for fish habitat managers and fishers, and build resilience for coastal communities. Mapping the vulnerability of marine fish habitats to the physical impacts of SLR due to climate change, will generate audits of the potential change in extent of mangrove and saltmarsh communities to be incorporated into development of local government planning schemes and related planning instruments to integrate adaptation strategies for accommodating fish habitat shifts.


1

In 2002i, Fisheries summarised available marine plant community data for each of the then coastal local government areas (LGAs) in Queensland. A copy of the spatial data was provided to alert individual local governments (LGs) to the presence and extent of the marine plant communities to provide supporting information for LGs undertaking ‘constraints mapping’ within Queensland planning law planning scheme-making process. This report documents the audits and methodology for the eight sites in the Moreton Bay region.

1.2 Project outline The purpose of this project is to increase understanding by state and local governments, fishing industry sectors and the community of the requirement for the landward and southward shifts in marine plant communities and other associated fish habitats as a result of climate change (SLR) through incorporating the audits about predicted shifts into coastal planning. Documenting and understanding these shifts in fish habitats will facilitate identification and planning for adaptation strategies that maximise the extent, diversity and ecosystem services of fish habitats into the future. The project has developed specific methodology for preparing high resolution vulnerability fish habitat maps for selected coastal regions. The maps are based on marine plant zone (Figure 1), digital elevation and contour data and 2009 aerial photography. A key aim of the project is to enhance coastal management through incorporation of these maps and the audits in local government planning instruments for use during development assessment processes. The methodology is able to be transferred through a data agreement so that local governments can apply it to other coastal regions.

Figure 1 Conceptual diagram showing the distribution within the marine plant zone The methodology provides:

spatial mapping and elevation modelling of the current extent of marine fish habitats (using marine plants as an indicator and most visible) in the selected regions; and

audits of the extent of marine plant zone (communities) between mean sea level (MSL) and the level of the highest astronomical tide (HAT) for current day distribution (base-line) and at 3 sea level rise scenarios of 25 cm, 75 cm and 100 cm for each region.

i Summary of Coastal Wetland Communities in Queensland by Local Government Area (de Vries, Danaher and

Couchman 2002)


2

Audits based on:

Model 1 – Constrained (losses only);

Model 2 – Unconstrained (losses and gains assuming marine plants can colonise landward); and

Model 3 – Unconstrained (losses and gains assuming marine plants can colonise landward and seaward, based on the Sea Level Affecting Marshes Model (SLAMM))

Support to local governments to recognise and achieve planning outcomes to include buffers and retreat areas for marine plant communities to establish in the future.

Two coastal regions have been selected along the east Coast - Moreton Bay, south-east Queensland and Townsville, North Queensland. To conduct audits on at least four sites within each region. This report documents the audits for the eight sites within the Moreton Bay region.

2. Methods

2.1 Mapping LiDARii elevation data has been proven to be useful in mapping the micro topography of mangrove intertidal habitats. Knight et al (2009) applied the methodology to map the hydro-dynamics of a mangrove system in southeast Queensland to identify the early life-history stages of the saltmarsh mosquito, a known insect pest and human disease carrier. The Queensland, Commonwealth and a number of Local Governments undertook a LiDAR acquisition program during 2008-2010 to provide data for the Improved Coastal Mapping project and for emergency services planning for evacuation routes in the event of natural disasters such as cyclone, storm surge and flooding events. This data was quality assured and rectified and forms the primary data set used for this project. Imagery used for the mapping included 2010 South east Queensland aerial photography (captured 2009) to define polygon extent (seaward mangrove edge and HAT) for the baseline distribution. Imagery resolution was 0.5 m resolution for all sites except Boondall wetlands (MB05) which had 0.15 m resolution. The methodology for the habitat mapping component involved four main stages:

review of currently available datasets for both vegetation and bathymetric data;

acquisition of processed LiDAR 25 cm contour polygon data and current imagery;

refinement of site selection through initial use of C-Fish catch grids and integration with Queensland Herbarium long-term monitoring of mangrove and associated communities project sites; and

geoprocessing, using ESRI ArcGIS software, once LiDAR extents were selected in respect to the current day habitat extent. LiDAR polygons were further simplified to provide single polygons for each 25 cm increment.

ii LiDAR – Light Detection and Ranging remote sensing technology that uses light to map elevation at high resolution.


3

The extensive LiDAR dataset available required a sampling approach to be taken to set a limit on the size of the sites within Moreton Bay. The area for each site was refined through consideration of the calculation of HAT zones and capture of significant marine plant communities. LiDAR polygons were ‘clipped’ out from the main dataset between 0.00 AHD and 3 m AHD and further simplified to single polygons for each contour level.

Each site in Moreton Bay varies in size, mapped scale and extent of marine plants covered in the audits produced for current day and each of the three SLR scenarios:

current day MSL is set as the baseline at 0 cm;

SLR 25 cm;

SLR 75 cm; and

SLR 100 cm.

Up to eight polygon levels per SLR scenario were mapped at each site (Figure 2). The landward extent mapped was to 1 m above current day HAT level for each site. The seaward (outer) edge of the mangrove community was adopted as the MSL level and aligned with the nearest 25 cm LiDAR contour. This contour is set as the baseline (C1 in Figure 2) for the initial base-line audit. The total of the inter-contour areas - between C1 and C2, C2 and C3, C3 and C4, and C4 and C5 - is taken as current (base-line audit). For the three SLR scenarios; the total of the inter-contour areas is:

SLR 25 cm audit - between the C2 and C6 contours;

SLR of 75 cm audit - between the C4 and C8 contours; and

SLR 100 cm audit - between C5 and C9 contours.

Figure 2 MSL, HAT, LiDAR contours and sea level rise scenarios


4

2.2 Modelling The project provides high resolution fish habitat vulnerability mapping for the selected coastal regions for areas with different levels of development (developed shoreline versus undeveloped shoreline). The project mapped intertidal vegetation between MSL and the HAT and included predominately mangrove forests and to a lesser extent, saltmarsh communities (Figures 2 and 3).

Figure 3 Tidal profile (Adapted from the OzCoasts website, Geoscience Australia). Three models were used to determine the impacts of the adopted SLR scenarios in terms of losses and gains of extent of marine plant communities for the eight Moreton Bay sites. Each model is explained in detail below. Model 1 – Constrained. This model assumes no capacity for shift in marine plant communities (Figure 4). Therefore the audit is a calculation of losses only due to permanent inundation of the seaward edge of the marine plant community under the SLR scenarios (Table 4). In Model 1, the claypan and saltmarsh communities provide the only initial retreat capacity (IRC) for mangrove communities to move into (Figure 1). Physical and chemical barriers, armouring of property and infrastructure, and lack of time for marine plants to adjust constrain the marine plant community shift. MSL moves landward but HAT is fixed.

Figure 4 Model 1 – Marine plant zone reduced as sea level rises; losses only.


5

http://www.ozcoasts.gov.au/conceptual_mods/processes/habprov.jsp

Model 2 – Unconstrained. This model assumes marine plant communities have capacity to colonise new upland areas and to keep pace with SLR and that there are no physical or chemical barriers (Figure 5). Claypan and saltmarsh communities are the initial retreat areas for mangrove communities, with further shift into lands above HAT. The audit includes losses and gains for each SLR scenario. Both MSL and HAT move landwards.

Figure 5 Model 2 – Marine plant zone shifts landward as new areas colonised with SLR. Model 3 – Unconstrained. This model assumes marine plant communities have capacity to colonise and to keep pace with SLR and that there are no artificial physical or chemical barriers. This incorporates accretion and erosion rates for Moreton Bay (Lovelock et al, 2011) and specific responses (marine plants) to SLR scenarios (Figure 6). Audits provide a modified shift estimate of losses and gains of marine plant communities through the application of the Sea Level Affecting Marshes Model (SLAMM), as adapted for Moreton Bay by the University of Queensland (O’Mara 2011). The model provides scope for marine plant communities to move both landward and seaward due to sedimentation building up the seaward edge. The sedimentation comes mostly from land-based soil erosion, but also from marine currents which carry and/or remobilise sediments. Both MSL and HAT move landwards.

Figure 6 Model 3 – Marine plant zone shifts landward and seaward with SLR.


6

A timeframe has not been set for the SLR scenarios used for this project, although an average rate of SLR of ~1 cm/year is accepted. For comparison purposes with the coastal hazard inundation mapping undertaken for the Coastal Plan, the 75 cm SLR scenario equates to the 80cm by 2100 SLR scenario adopted for the Queensland Coastal Plan. Model 3 is based on sedimentation rates on tidal flats (Lovelock et al 2011) for Moreton Bay of 6 mm/year (high) and 1.5 mm/year (low). The SLAMM output uses modified vegetation types, based on Dowling and Stephens 1998 vegetation mapping (see section 7). One of the predicted outcomes from Model 3 is the expansion of the upper intertidal mangrove species at the expense of saltmarsh communities.

2.3 Communication The mapping will enable the impacts of future sea level rise on marine plant distribution to be incorporated when making planning decisions, so that the future shifts can be anticipated and accommodate in coastal planning through identification and formal establishment of buffers and retreat areas. To facilitate the uptake of the mapping and future use of the developed methodology for additional mapping by local governments, stakeholder meetings with each local government in the Moreton Bay region have been held. The final audits for the Moreton Bay region have been communicated to the relevant local government and the fishing industry at stakeholder meetings (see section 6 for a summary of consultation activities). Data agreements are in place for use of the audit data in local government planning and development assessment processes. The methodology has also been provided to allow local governments to complete audits for the balance of the marine plant communities within their council area. Local, site-specific information on the likely SLR impacts for locally important fish habitats have been highlighted in the work undertaken for this project. The important value of this information was quickly recognised by local government officers, in particular natural resource managers and planners, to provide visual representation of future needs for coastal communities. The audits and maps are powerful tools to assist in strengthening local government planning schemes and regional plan adaptation strategies for how and where the landward migration of marine plants and tidal fish habitats are to be accommodated to ensure that the current diversity of fish habitat remains.

3. Study area Mangrove species are adapted to different levels of tidal inundation, soil type and freshwater inflow which results in particular species occupying sometimes quite distinct zones in the intertidal wetlands (Duke, 2006). In south east Queensland, mangrove communities are typically identified by zones of the pioneer species Avicennia marina along the seaward edge or a mix of Avicennia and the river mangrove Aegiceras corniculatum, especially along estuarine river banks. Landward of this zone will be Rhizophora and Bruguiera species in wetter areas or Ceriops sp. Blind-your-eye (Excoecaria agallocha) mangroves often grow at the top of the bank (Figure 7).


7

Figure 7 Mangrove zonation (adapted from NSW DPI Mangrove Primefact, 2008). The region supports the highest density and fastest growing human population on the Queensland east coast and is home to major shipping, airport and industrial hubs and transport, power and water infrastructure corridors. Moreton Bay is also a Ramsar wetland site of international significance. Despite the proximity of a major city of over 2 million people, Moreton Bay remains highly productive providing for nearly 10% of the commercial fish catch in Queensland and supporting a large recreational catch. The study area extends over eight sites (Figure 8) from Coomera Island (MB01) in the south to the Pumicestone Passage and Glasshouse Creek (MB08) to the north along approximately 150 km of coastline. The region is sub-tropical and supports extensive mangrove (six species) and saltmarsh (~20 species) communities, a percentage of which are within protected areas: declared Fish Habitat Areas and marine and conservation parks. The mangrove and saltmarsh / saltpan wetlands of the Moreton Bay study area cover approximately 13 500 and 3800 hectares respectively (Dowling and Stephens, 1998). For the Pimpama River flowing into southern Moreton Bay, a case study was undertaken of the impacts of climate change as part of the National Coastal Vulnerability Assessment. The study identified major risks of SLR as those associated with ‘drowning of marine plants’ and tidal inundation of agricultural land (DCC 2009). For this catchment, a proposed desirable response is a planning process that recognises regional opportunities for natural adaptation as well as protecting settled areas and valuable assets.

3.1 Fish habitat diversity Moreton Bay is a large semi-enclosed embayment of shallow, warm estuarine waters fed by six rivers (Caboolture, North Pine, Brisbane, Logan, Albert / Pimpama and Coomera) and protected by the large sand islands of Moreton, North and South Stradbroke. The diversity of mangrove species increases with lower latitudes with over 35 species being recorded from the tropical north (Duke 2006). Saltmarsh species increases in diversity with higher latitudes. This makes Moreton Bay, as a transition zone, an important place for mangrove and saltmarsh biodiversity in Queensland. The sub-tropical environment supports at least six species of mangroves, with the Grey Mangrove (Avicennia marina subspecies australasica) being the most common. The other recorded species are the River Mangrove (Aegiceras corniculatum), Red Mangrove (Rhizophora stylosa), Orange Mangrove (Bruguiera gymnorrhiza), Yellow Mangrove (Ceriops tagal) and the Milky Mangrove (Excoecaria agallocha). A high diversity of saltmarsh plants also occurs along with seagrass meadows, macro-algae and microalgae.


8

There are 25 common species of saltmarsh that are described in the Field Guide to Common Saltmarsh plants of Queensland (Johns, 2010). As saltmarsh and claypan communities occur high in the intertidal zone, these communities are most at risk at permanent higher inundation levels and more frequent very high tides as a result of SLR. These communities will be colonised by mangrove species, depending on the rate of SLR and erosion and accretion factors. Within the state of New South Wales (NSW), saltmarsh habitats are ranked as an “endangered ecological community”, under the provisions of the NSW Threatened Species Conservation Act 1995.

3.2 Wild-harvest fisheries Moreton Bay supports a number of commercial and recreational (including charter) wild-harvest fisheries. These fisheries provide local employment directly in the industry and in associated businesses and services for the processing and sale of seafood as well as the purchase, repair and maintenance of fishing vessels and equipment. In 2006, the commercial fisheries of the Moreton Bay region contributed 10% ($18.5 million) to the overall Gross Value of Production (GVP) for seafood harvest in Queensland (GVP $185 million). The key commercial and recreational fisheries that operate in or close to the greater Moreton Bay region are summarised below. Table 1 Summary of wild-harvest fisheriesiii operating in or near Moreton Bay

Fishery

Main species value Key habitats

River and inshore beam trawl fishery (RIBTF) 2011 status report. Approx 475 t for commercial harvest and approx 36 t for Recreational (prawns and squid) for Qld

Prawns (Greasyback, banana and school) make up most of the commercial catch with squid and Moreton Bay bugs a very minor part.

GVP in 2010 was $3.2 m (commercial catch) Approx 75% of the catch from this fishery for Queensland is taken in the Moreton Bay to Noosa region

Soft substrates including mud, silt and sand; Riverine and estuarine wetlands

East Coast inshore finfish fishery (ECIFFF) 2009-2010 status report. Approx 7928 t (all sectors) for Qld state’s most diverse fishery. Commercial 4843 t Recreational 3000 t (in 2005) Charter approx 85 t

Commercial–sea mullet, shark, whiting, bream, flathead, tailor, small mackerels, threadfins, barramundi and garfish Recreational–whiting, bream, trevally, flathead, dart, tailor, barramundi, grunters, threadfins and small mackerels

GVP in 2009-2010 was $19.6 m (commercial catch) Sea mullet is the largest catch (commercial) by weight (1754 t) with most caught Fraser Island south. Also shared with NSW.

A mosaic of habitats supporting inshore, estuarine and ocean beach fish species and including seagrass, mangrove and saltmarsh communities as well as sand, silt and mud substrates.

Blue swimmer crab fishery (2011 status report)

Blue swimmer crabs (Portunus armatus)1

GVP in 2010 was $4.2 m (commercial pot harvest)

Juveniles inhabit shallow seagrass meadows, sand and

iii Fisheries catch data and annual status reports are available from the Fisheries Queensland website


9

http://www.dpi.qld.gov.au/28_19545.htm







Fishery Main species value Key habitats

Commercial 514 t Plus unrecorded recreational & Indigenous catches

Moreton Bay averages approximately 335 t annually of pot caught blue swimmer crabs—calculated from 2000 to 2010 inclusive.

mud banks in and around estuaries. Adults inhabit deeper waters and shallow sandbank areas within bays and estuaries, and in offshore waters.

East Coast Otter Trawl Fishery (ECOTF 2010 status report)) The fishery is the largest in Queensland, in terms of both the volume of product caught and economic value of the product. Total harvest approx. 7880 t (2009)

Prawns: Eastern king, red spot king, brown tiger, grooved tiger, blue endeavour, banana, school, greasyback, bugs: Moreton Bay, Balmain bug; lobsters; slipper, red champagne; crabs: blue swimmer, three-spotted; mantis shrimp, squid, saucer scallop, octopus, cuttlefish, threadfin bream and pipefish.

GVP in 2009 was $99 m Moreton Bay region harvest for the main species was approx 483 t or 6% with prawns the bulk of the catch.

Main species caught (squid, scallops, bugs & prawns) inhabit sandy substrates as adults and seagrass meadows, mud and sand banks adjacent to mangrove communities as juveniles.

Mud Crab Fishery (2011 status report) Harvest for fishery (2010) Commercial 1192 t Recreational 638 t

Mud Crab Scylla serrata

GVP in 2010 was $19.1 m Mud crab catch is distributed around the state, with higher catch south of Hinchinbrook Island. Highest harvest areas are Moreton Bay, Gladstone, Broadsound (north of Rockhampton) and Hinchinbrook Island (north of Townsville).

Juvenile and adult mud crabs live in sheltered estuaries, tidal reaches of mangrove-lined rivers and streams, mangrove forests and mud flats. Egg bearing females migrate offshore to release their eggs. Larvae eventually drift back to shore to settle in shallow water habitats.


10




Figure 8 Location of the 8 Moreton Bay study sites, showing CFish reporting grids.


11

3.4 Site description Table 1 provides a summary of each site and lists its name, location, current marine plant area and a brief description. Composite SLR scenario maps of Model 2 for each site are in Appendix 1. Table 2 summary information for all Moreton Bay sites

Site Location Protected area Area (ha) marine plants

Scale Description

MB01 Coomera Island

27 o 50' 58.924" S

153 o 23' 13.164" E

Coomera FHA 813 1:20 000 Undeveloped sand / mangrove Island, next to highly developed urban area

MB02 Russell Island

27 o 39' 31.32" S

153 o 20' 13.2" E

None 102 1:15 000 Developed island, NW section

MB03 Pannikin Island

27 o 39' 04.68" S

153 o 19' 55.2" E

None 366 1:15 000 Undeveloped mangrove island

MB04 Eprapah Creek

27 o 33' 51.84" S

153 o 17' 23.964" E

None 245 1:12 500 Urban mangrove lined estuary

MB05 Boondall Wetlands

27 o 21' 07.56" S

153 05' 13.236" E

Moreton Bay Ramsar Wetland

345 1:20 000 Modified mangroves / saltmarsh wetlands adjacent to major airport & road

MB06 Freshwater Creek

27 o 15' 26.64" S

153 o 02' 34.8" E

Hays Inlet FHA 639 1:20 000 Largely unmodified urban mangrove lined estuary

MB07 Caboolture River

27 o 07' 28.556" S

153 o 01' 29.964" E

Deception Bay FHA

876 1:37 000 Modified urban mangrove lined estuary

MB08 Ningi-Glass Mountain Creek

27 o 01' 07.32" S

153 o 03' 54.0" E

Pumicestone

Channel FHA

1424 1:37 500 Large semi-urban mangrove lined estuary


12

3.3 Historic marine plant mapping for Moreton Bay Marine plant distribution has been mapped for Queensland during the period 1990-2001 at 1:100 000 scale using remote sensing data (for example Danaher 1995a; Bruinsma et al 1999) as part of the Queensland Coastal Wetlands Mapping Project. Marine plant distribution has been used as a surrogate for acid sulfate soils distribution in coastal areas. Mapping of acid sulfate soils at a finer scale of 1:25 000 has been undertaken for sites MB06 (Walton et al 2011) and MB07 (Malcolm et al 2006). This mapping may also indicate the extent of future marine plant migration, recognizing that SLR and increased inundation frequency will reduce the level of acid generation from these soils. In 1998, the Queensland Herbarium mapped the coastal wetlands of South East Queensland from the Tweed River to the Sunshine coast. This study included coastal vegetation to the 2.5 m contour above AHD and extended across the entire Moreton Bay region. The area of each marine plant group (GVP) within each local government area was calculated and is presented in Table 2. Under Model 1, the IRC for marine plants will only be the claypan (GVT2) and samphire habitats (GVT3). Mangroves (GVT1) will expand into these areas at the expense of the existing communities. Table 3 Extent of marine plant groups per LGA (based on Dowling & Stevens 1998)

LGA name Mangroves GVT1

Claypan

GVT2

Samphire

GVT3

Grassland

GVT4

Total ha

Moreton Bay Regional

2863.7

(67%)

715.7

(17%)

209.7

(5%)

498.9

(11%)

4288

Redland City 3421.9

(87%)

416.1

(10%)

20.8

(<1%)

83

(2%)

3941.8

Logan City 18.1

(60%)

0 0 11.8

(40%)

29.9

Brisbane 2230.1

(78%)

387.9

(13%)

25

(1%)

234.3

(8%)

2877.3

Gold Coast City

5014.8

(81%)

515

(8%)

112.4

(2%)

562.3

(9%)

6204.5

Total 13 548.5 2034.7 367.9 1390.3 17 341.4

4. Results For each of the eight sites in the Moreton Bay region, the extent of marine plant distribution was calculated as an audit, commencing with current day (baseline at 0 cm) and followed by each of the three SLR scenarios: SLR 25 cm; SLR 75 cm and SLR 100 cm. Models 1 and 2 were applied by Fisheries and Model 3 by University of Queensland. From the audits generated, the impacts of the adopted SLR scenarios were determined in terms of losses and gains within the extent of marine plant communities for each of the eight Moreton Bay sites.


13

The Models 1 and 2 audit cover 28% of the total marine plant community area in Moreton Bay (1998) of about 17 300iv ha of which approximately 13 500 ha is mangrove community. The total areas assessed and calculated for the Model 3 audits vary with those of Models 1 and 2 as the mapped areas for Model 3 included the entire grid that bounded each site. The Model 1 and 2 audits were based on a subset of the site grid to capture a coherent wetland system and to simplify the production of the contour polygons for the project. The following sections provide summaries of the audits and impacts of the SLR scenarios on the extent of marine plants for each of the eight Moreton Bay sites and collated for each of the four local government areas for each of the three models (as per Section 2 - Methods).

4.1 Model 1 results The audits, based on Model 1 (Table 4) - the constrained approach where the intertidal areas are inundated progressively (and marine plants are lost) as the sea level rises - do not accommodate landward migration. This is a ‘worst case’ scenario as it does not take into account any ability for landward migration of marine plants which could be prevented from moving due to human or natural barriers, or an inability to keep pace with the rate of SLR. For each of the eight sites in Moreton Bay, relatively little loss occurs between the baseline and SLR 25 cm. Substantial losses do occur - SLR 25 cm to SLR 75 cm - including total loss of the marine plant community at MB01. Further substantial losses follow with the final 25 cm SLR to 100 cm. At the 100 cm SLR, five of the eight sites no longer have marine plant communities. Only the three sites in the Redland local government area retain marine plant communities and these occupy only 67% of the baseline communities of southern Moreton Bay. Overall for Moreton Bay, 95% of the marine plant communities are lost. Table 4 Model 1 audit summary Southern Moreton Bay Northern Moreton Bay

Site Area (ha)/

MB01 Coomera

Island

MB02 Russell Island


MB04 Eprapah Creek


MB06 Freshwater

Creek

MB07 Caboolture

River

MB08 Ningi-Glass

Mountain Creek

Total Area (MB

Region)

SLR cm

GCCC RCC BCC MBRC (ha)

Current

813 103 366 245 345 639 876 1424 4811

SLR 25

706 89 348 227 316 618 826 1280 4410

SLR 75

0 58 278 171 298 406 419 392 2022

SLR 100

0 30 159 47 0 0 0 0 236

Change per LG @ 100

- 100% - 67% - 100% - 100% - 95%

iv Dowling and Stevens 1998 Grouped Vegetation Types (GVT) 1 to 4 for the Moreton Bay Study Area: Mangrove

13500ha, Claypan 2030ha, Samphire 370ha, Saline Grassland 1400ha


14

4.2 Model 2 results The audits based on Model 2 (Table 5) - unconstrained – accommodate migration of marine plants landward into areas with suitable elevation. Soil type, accretion, erosion and impacts of extreme events are not components of the Model. With this Model, losses are marginally lower than those from Model 1 for the four southern Moreton Bay sites. However for the four northern Moreton Bay sites, there are considerable gains at each site at SLR 100 cm, although earlier substantial gains at SLR 25 cm and SLR 75 cm have been reduced. Table 5 Model 2 audit summary Southern Moreton Bay Northern Moreton Bay

Site Area (ha)/

MB01 Coomera

Island

MB02 Russell Island


MB04 Eprapah Creek


MB06 Freshwater

Creek

MB07 Caboolture

River

MB08 Ningi-Glass

Mountain Creek

Total Area (MB

Region)

SLR cm


Current

813 103 366 245 345 639 876 1424 4811

SLR 25

797 98 372 269 415 778 1304 1791 5824

SLR 75

188 82 303 274 610 904 2186 1574 6121

SLR 100

109 59 184 162 479 562 2335 1416 5306

Change per LG @ 100

- 87% - 43% + 39% + 47% + 10%

Changes in extent of the marine plant community vary at each site depending on the tidal regime and topography, natural contours and presence / absence of hard structures such as revetment walls or roads. For southern Moreton Bay (MB01-MB04) the audit indicates a loss of marine plant extent of 67% at the 100 cm SLR scenario. In the northern part of Moreton Bay (MB05 – MB08) there is a gain of 46% of marine plant community extent at the 100 cm SLR scenario. The overall result for the Moreton Bay study area at the 100 cm SLR scenario is a gain of 10%, predominantly within the lower Caboolture River catchment with its 266% gain at SLR 100 cm.

4.3 Model 3 results The audits based on Model 3 (Table 6) – unconstrained – accommodates accretion and erosion data for Moreton Bay. Marine plants are able to colonise both landward and seaward. Model 3 audits are an outcome of the application of the SLAMM project undertaken by the University of Queensland (O’Mara 2011, Honours thesis). The SLAMM Model 3 audits include extent calculations for 19 adapted vegetation types.


15

These have been grouped for the purposes of the Fisheries project into four broad zones:

Terrestrial - urban area (developed); natural vegetation (undeveloped);

Adjacent - Melaleuca, Sedgelands, Grasslands, Casuarina;

Marine plant - Sporobolus grassland, Claypan, Samphire, Mangrove upper, Mangrove lower; and

Aquatic and beach - Melaleuca Riverine, Inland water, Riverine water, Tidal flats, Tidal creek, Beach, Ocean.

Appendix 3 contains a summary of SLAMM information for each site for all adapted vegetation types. Table 6 Model 3 audit summary Southern Moreton Bay Northern Moreton Bay

Site Area (ha)/

MB01 Coomera

Island

MB02 Russell Island


MB04 Eprapah Creek


MB06 Freshwater

Creek

MB07 Caboolture

River

MB08 Ningi-Glass

Mountain Creek

Total Area (MB

Region)

SLR cm


Current 1266 112 463 264 550 1149 1004 1642 6450

SLR 25 1368 113 466 320 634 1240 1413 2035 7589

SLR 75 1389 107 424 313 812 1503 2367 2639 9554

SLR 100

1377 111 418 272 889 1567 2887 2839 10 360

Change per LG @ 100

+ 8% - 5% + 38% + 92% + 61%

The Model 3 audits indicate for the southern Moreton Bay sites (MB01 to MB04), there is a marginal increase of 3.5% at the SLR 100 cm. Increases are substantial and continuing shifts in the marine plant communities in the northern part of Moreton Bay (sites MB05 to MB08) as SLR increases. Overall for Moreton Bay the increase in the area of marine plants in the Bay is 61%. These audits also indicate that with expansions both seaward and landward of mangrove communities there will be concurrent increases in the linear perimeter of each mangrove community. These increases in mangrove perimeter provide greater connectivity and enhanced access to shelter and feeding habitats for fish, prawn and crab stocks and corresponding increases in fisheries productivity (Meynecke et al 2008).

4.4 Project status

4.4.1 Fish habitat vulnerability Approximately 30% of the Moreton Bay marine plant community has been assessed within eight sites. Audits of the changes to the marine plant zone at each site have been completed for each SLR scenario. As described above, the audits indicate there are variable opportunities to accommodate buffers and retreat areas for the landward migration of marine plants.


16

For example for MB03 (Pannikin Island), Models 1 and 2 show losses of at least 50% or more while Model 3 for this site shows a 10% loss. This reflects the nature of this island site with its limited opportunities for landward migration due to the absence of high ground. Overall, for the Bay at the 100 cm SLR scenario, Model 1 shows a 95% loss; Model 2 shows an increase landward of 10% while Model 3 shows an increase both landward and seaward of 61%. These increases would occur at the expense of adjacent sensitive coastal freshwater swamps through colonisation by the mangrove community in an unconstrained system where no defence measures are taken to protect coastal assets, both built and natural.

4.4.2 Queensland Herbarium The Queensland Herbarium has initiated a concurrent long-term project to monitor and map changes to mangroves and associated marine plant communities in Moreton Bay. There are 20 permanent monitoring sites being established, 80% of which are located within the eight Moreton Bay project sites. As at May 2012, 10 (50%) of the monitoring sites have been established. This project will document the long-term changes resulting from SLR as this continues and marine plant communities shift. A more detailed summary of the project is provided in part 7 of this report.

4.5 Implications of audits The distribution of marine plant species along the tidal profile is also going to change as sea level rises and the tidal profile and its extent change. Saltmarsh and mangrove species occupy distinct niches and zones which are determined by elevation, soil type, frequency of tidal inundation, influence of freshwater runoff and groundwater, latitude and nutrients among other things (Duke 2006; Johns 2006; 2010; Saintilan 2009). What seems likely and which has been recorded in other estuaries along the east coast of Australia (Saintilan and Williams 1999) is that mangrove communities will invade saltmarsh areas. This will mean that the gains in marine plant communities for Moreton Bay will largely be at the expense of saltmarsh and adjacent sensitive freshwater communities (e.g. paperbark (Melaleuca) forests and swamps). Saltmarshes are critical habitats for local and migratory bird species as well as fish species and provide important nutrient exchanges through the connectivity between the terrestrial and marine environments. The adjacent freshwater communities are of high fisheries and ecological values and often remnant, following coastal development. Freshwater habitats are critical to fish species that are anadromous (move onto freshwaters to spawn) or are catadromous (move to estuaries and inshore waters to spawn). There is recent evidence of changes to the distribution and extent of mangroves recorded in other Pacific Island countries and territories. Waycott et al (2011) note a gradual retreat of the mangrove zone due to SLR rate of 0.7 mm per year in southern PNG (PCCSP 2011). There the dominant Bruguiera mangrove species has been replaced by Rhizophora species. Mangroves are sensitive to even minor changes in coastal conditions, such as altered drainage patterns, tidal heights, saltwater intrusion, accretion or erosion in response to changes in sea level. The response of mangroves to these changes can be seen through variations in the community composition (zonation) and relative abundance of plant species within the mangrove habitat (Waycott et al 2011; Duke 2006). Given the dependence of fish, prawns and crabs on marine plant communities (Ley 2005) as a source of primary production, any changes within these communities will impact on the composition, distribution and abundance of the fish and invertebrate communities on which commercial, recreational and indigenous fisheries rely. The recent Australian Society for Fish Biology Conference (2010) allowed presentation and technical debate (MAFR 2011) on the impacts of climate change and Australian aquatic environments, confirming the key impacts, currently being documented and/or predicted to occur, on fish stocks and fish species.


17

5. Adaptation to SLR risk A consequence of SLR for each of the models is the likely changes that will occur in both the diversity and extent of intertidal marine plant communities. Where there are limited or no retreat opportunities available due to steep banks or existing hard engineering structures such as revetments, bunds and walls, intertidal marine plant communities will be lost completely or substantially reduced to a narrow band (Model 1). Similarly for Model 2, even though marine plants may be able to migrate landwards if the substrate and slope are suitable, the suite of marine plant species will reduce and mangroves will out-compete and dominate saltmarsh species; the latter becoming less diverse, if not lost. Results of the Model 3 audits indicate that the extent of the mangrove community will expand but at the expense of sensitive upland freshwater systems and saltmarsh. These audits also indicate that the more productive lower mangrove communities will be lost while the upper mangrove communities will expand. Access by fish and invertebrates is less frequent and of lower duration in the upper mangroves. The length of mangrove edge along the foreshore will also expand under the Model 3 SLR scenarios. This will increase the feeding, shelter and nursery areas available to aquatic species and could increase fisheries productivity for mangrove dependent species. Adaptations to the changes in intertidal vegetation extent and diversity and fisheries productivity due to the impacts of SLR will involve consideration of various options. Some key adaptation options for consideration by the fishing industry and for local government are discussed below. Early in the project, a risk management matrix (Appendix 2) was developed to help summarise the various climate adaptation pathways that exist for fish habitats and fisheries production. A risk statement and a way forward were developed as part of the scoping process for the project and are reproduced below: Vulnerability of Fish Habitats (Marine Plant Communities) - RISK STATEMENT the risk to the fishing sectors of losing marine plant habitats will result in changes in

fisheries production, catch composition and seafood availability;

this level of risk requires an urgent response from senior levels of industry and from local, state and federal governments for policy and management; and

the risk can be mitigated through provision of retreat areas for marine plant habitats through strategic planning instruments at local and state government levels and through fishing sectors adapting catch and marketing strategies for changes in catch composition.

Vulnerability of Fish Habitats (Marine Plant Communities) - WAY FORWARD select key sites that are audited in terms of current marine plant distributions and their

diversity;

selected sites to reflect different coastal areas where low, medium and high levels of development (i.e. potential barriers);

develop several scenarios of SLR and map and audit likely changes in marine plant distributions and diversity; and

liaise with key stakeholders, e.g. local governments and fishing industry, to ensure that planning instruments consider future marine plant communities and by definition, future fish communities and catching of these.


18

5.1 Issue identification for stakeholders The risk management matrix in Appendix 2 identified the various risks that accelerated SLR, rising temperatures and greenhouse gas levels (primarily CO2) will have on the extent and distribution of marine plants and probable outcomes for local and regional fisheries production. Fishers and fisheries managers will need to develop alternative ways to access and protect fisheries resources. The Declared Fish Habitat Area (FHA) network will also need to be amended to reflect changes in critical fish habitat extent and distribution, including boundary definition. Meynecke (2009), states that maintenance of fisheries sustainability will be dependent on maintaining and placing new declared FHAs in areas with high structural connectivity within the fish habitat mosaic. A major risk to fish habitats is the loss of habitats due to ‘coastal squeeze’ (Figure 9) where barriers such as man-made structures or natural land features prevent the SLR imposed landward shift of marine plants. Appropriate regional and local planning along coastal foreshores may limit the extent of the ‘coastal squeeze’, especially in areas deemed to be high fish habitat and fisheries values.

Figure 9 Loss of fish habitats due to ‘coastal squeeze’ adapted from DCC 2009 report.

5.1.1 Local government A key outcome of the project was to provide audits at a local level on the impacts of projected SLR on coastal fish habitats to alert local governments and to encourage and to support planning and assessment decisions in the coastal zone. The audits provide a visual and spatial tool to enable use of the data in local government GIS, planning schemes and assessment systems. Data agreements are in place to encourage and facilitate use of the audits in council planning. Options that the state and local governments can consider include: Do nothing – no consideration of fish habitats or fisheries

continue with business as usual, making no concession or investment for protection of future fish habitats;

no strategic approach to planning and protection of key conservation values;

decline of local fishing industry and fresh seafood to the community as fisheries production is lost; and

recreational fishing opportunities and local supporting industries decline.


19

Reactive – ‘as needed’ consideration of fish habitats or fisheries

ad hoc protection of threatened adjacent freshwater biodiversity values and foreshore habitats;

multiple competing conservation values are not holistically dealt with;

private and public property defence with armouring is unmanaged;

no planned retreat; and

decline of local fishing industry and fresh seafood as fisheries production is lost. Proactive – strategic consideration of fish habitats or fisheries

strategic protection of mapped key fish habitats and retreat / buffer areas;

coordinated conservation management objectives for biodiversity values;

integrated insect pest management;

strategic approach to coastal planning with ‘soft’ retreat and resilience building approach; and

assessment of coastal developments that includes a risk management approach to SLR and increased exposure to coastal hazards.

The Queensland Coastal Plan 2012 now requires local governments to prepare coastal hazard adaptation plans for those areas that have been developed that may be at risk of an 80 cm SLR at 2100. Zeppel (2011) reported on a review of the different climate change adaptation action approaches used by four coastal Councils (Cairns, Gold Coast, Redland and Sunshine Coast) in Queensland, in response to the Coastal Plan. The adaptation responses reviewed were grouped into several categories including:

Emphasising Nature – focus is on protecting the environment to buffer the impacts of climate change;

Emphasising development – focus is on protecting the built environment;

Managing nature – actions include beach nourishment, artificial reefs;

Emphasising communities – focus is on public access, health risks, safety and engagement; and

Council governance – relates to internal council processes for dealing with climate change impacts.

Significant coastal public and private buildings and infrastructure are at risk in coastal Queensland (94 000 buildings, Qld Coastal Plan 2011) from predicted storm tides and SLR. This has led to the focus of local governments in primarily protecting the built environment from erosion. Out of 35 coastal Councils, only four have developed climate change strategies or action plans with the emphasis being on council governance to implement climate actions, along with actions emphasising nature to protect the environment, assets and public areas (Zeppel 2011). Fish habitats are now recognised as a “State Interest” under the planning legislation and local government planning schemes are required to include retreat areas to accommodate landward migration of marine plants.


20

In discussion with the Moreton Bay Councils, planning for retreat and buffer areas was recognised as a priority, as well as the future trade-offs that may need to be made in terms of protecting increasingly threatened freshwater ecosystems (e.g. Melaleuca forest) at the expense of landward migration of marine plants. Long-term protection to these communities within an LG conservation and management strategy is appropriate and a Moreton Bay regional approach, given the relative changes to southern and northern marine plant communities, may also be required.

5.1.2 Fishing industry Key considerations for the fishing industry include the changes predicted for the highly productive intertidal habitats are that support fish, prawn and crab nurseries; the reliance of inshore fisheries including recreational, indigenous and commercial fisheries and of offshore fisheries such as the charter, prawns and game-fish; all dependent on these intertidal habitats. Nationally, 2009-10 GVP for fisheries was $2.2 billion, with fisheries exports totalling $1.2 billion and imports $1.5 billion (ABARE, 2011). Australia currently imports 70% of its seafood and this imbalance is likely to increase if coastal fish habitats are not given protection through strategic planning and management. For the fishing industry sectors in Queensland, the GVP for 2011-12 is $448 million, of which the components are: $284 million commercial, $91 million aquaculture and approx $73 million recreational. Most coastal communities and related industries are reliant on local fishing industry sectors for the socio-economic benefits generated. Fishing industry adaptation options include a number of proactive and reactive responses. In part 5.3 the tunnel net fishery in Moreton Bay is highlighted as a case study. The East Coast Otter Trawl Fishery (ECOTF) has also been the subject of a vulnerability assessment to climate change impacts (GBRMPA 2011) where changes to species availability and other factors were investigated and discussed and the adaptive capacity of the industry was highlighted. In general, the adaptation options identified in the ECOTF workshops for the fishing industry include: Possible restructure of fishing industry

fishers opt out of industry;

fishers move into other fisheries;

government buyback schemes; and

consideration of impacts to coastal communities if the fishing fleet relocates.

Target species change

different fish species become economical to target; and

ensure market acceptability (e.g. bream species are replaced by mullet).

Gear changes required to be able to target different species

ability to innovate and trial; and

rapid uptake.

Fishery management

area fished changes;

fished species abundant in new areas; and

flexible management arrangements.


21

5.2 Regional context The boxed table in Figure 10 below provides an estimate, based on the Model 2 approach, of the percentage loss of mangroves and seagrass habitats in 2035 and 2100 for Pacific Island countries and territories (PICTs). The effects of SLR are expected to result in losses of around 10% of mangrove habitat by 2035. By 2100, ‘likely’ losses are predicted to be around 50% to 60% in most of these PICTs, with losses of up to 80% predicted as ‘somewhat likely’ (e.g. Tonga), Waycott et al( 2011, page 345).

Figure 10 Projected loss of mangrove and seagrass habitats in Pacific Island countries and territories The above figure provides a snapshot of what current SLR predictions for the Tropical Pacific will mean for intertidal and subtidal marine fish habitats in the region. For Moreton Bay, the impacts of sea level rise will vary from north to south (Table 3) at the different scenarios.

5.3 Case study – Moreton Bay Tunnel Net fishery In Moreton Bay, the commercial inshore net fishery utilises both mesh nets and tunnel nets to harvest seafood for local fresh seafood markets. In Queensland, tunnel nets are restricted to the Great Sandy Straits near Fraser Island and Moreton Bay where catches are made all year round with peaks in late summer, early autumn and winter (MBTNF Code of Practice Jan 2012). The fishery relies on identifying suitable areas along gently sloping mangrove shorelines to ‘set’ the nets (~1800 m) at high tide, with fish being channelled into the tunnel end of the net for harvesting as the tide falls (Figure 11).


22

The fishers, in cooperation with OceanWatch Australia and SeaNet have recently released a YouTube video showing tunnel net operations and sustainable fishing practices www.youtube.com/watch?v=owiIZ5JElxk Figure 11 A tunnel net is set along a mangrove shoreline in Moreton Bay (Photo by Chris Calogeras, C-AID Consultants) The MBTNF annually (1990 – 2010) harvest around 300 – 600 tonnes of fish (~$1.2 – $2.4 million value) of a variety of species. These species are dependent on mangrove, saltmarsh and seagrass habitats and include banana prawns, mudcrabs, mangrove jack, bream, mullet, whiting and flathead. This catch is marketed directly to seafood wholesalers and retailers in the Moreton Bay region, supporting the local economy and providing fresh seafood. There are only 21 tunnel licences in Moreton Bay. MBTN operations are limited to a small number of specified areas that were determined many years ago based on social and operational parameters (MBTNF 2012). Further, operational constraints such as sea bed topography and restriction under legislation to only 5% of the bay being open for tunnel net fishing means that only 1% of the bay is actually fished. The characteristics and operational constraints of the tunnel net fishery mean that changes to mangrove shorelines due to SLR and climate change are likely to have significant impacts. As SLR increases there will be even fewer suitable netting sites available for tunnel net fishing. Without adaptation, this will impact on the number of fishers, supply of local seafood and the viability of the industry in Moreton Bay, leading to a greater reliance on imported seafood and loss of a historically significant Queensland fishery. There are options for adaptation to the changing availability of fishing sites and catch of species, including displacement of fishing effort to other areas, higher competition for remaining sites and the introduction of new fishing methods targeting the same and / or different species.

6. Stakeholder consultation An integral component of conducting and delivering the project has been early and continued communication with key stakeholders. The Moreton Bay region has five local governments, with the eight study sites located within four of these: Gold Coast City Council (MB01), Redland City Council (MB02, MB03, MB04), Brisbane City Council (MB05) and Moreton Bay Regional Council (MB06, MB07, MB08).


23

No sites were located in the Logan City Council area. Meetings were held with each Council at various stages of the project to provide information on the project objectives and to seek feedback on the best way to integrate the audits into each Council’s GIS, planning and development assessment processes. Local governments are key stakeholders as the principal land managers on the coastal zone. The future management and protection of identified retreat and buffer areas within this zone is primarily their responsibility. The other major stakeholders for the project are the fishing industry sectors. Regular meetings have been held with the Queensland Seafood Industry Association (QSIA) and the Moreton Bay Seafood Industry Association (MBSIA) to update the commercial industry sector on progress and implications from the project. As discussed earlier (section 5.3) in the report, commercial tunnel net fishers are vulnerable to changes to mangrove shorelines and coastal topography as impacts of climate change and SLR. The Tables below provide a summary of stakeholder consultation for the project. Table 7 Local government consultation

Stakeholder

Presentation / briefing Comments

Moreton Bay Regional Council Sites: MB06 Freshwater Creek

(Hays Inlet) MB07 Caboolture River MB08 Ningi-Glass

Mountain Creek

July 2011 – Early consultation to gauge interest and refine project sites

Oct 2011 – progress presentation & provision of data

December 2011 – Final audit results for Moreton Bay study area

Positive and constructive interaction with Council staff from first meeting

See audits as providing a visual representation of local sea level rise impacts from an environmental (fisheries) perspective

Committed to including information in Council GIS / planning systems

Request to present results to Council meeting, once 2012 elections are held

Brisbane City Council Site: MB05 Boondall Wetlands

July 2011 – consultation to raise awareness of project and discuss Boondall wetlands site


March 2012 – Presentation to BCC planning officers

April 2012 – BCC Northern Seminar series presentation

Positive response to presentation – realisation of impacts to remaining freshwater wetlands at site

Implications for management options / infrastructure planning (e.g. boardwalks)

Option to present results to BCC regions

Redlands City Council Sites: MB02 Russell Island

(NW) MB03 Pannikin Island MB04 Eprapah Creek

May 2011 – Early consultation to gauge interest and refine project sites


Positive response to presentation

Dealing with multiple agency requirements for buffers and setbacks for conservation and biodiversity issues

Keen to draft joint media release / communications about project results


24

Stakeholder Presentation / briefing Comments

Gold Coast City Council Site: MB01 Coomera island

August 2011 – Early consultation to gauge interest and refine project site

September 2011 – Climate change officers briefing

December 2011 – final audit results for Moreton Bay study area

Positive response to presentation

Aligned with detailed mapping work GCCC undertaking in the Coomera area

Townsville City Council

August 2011 – Presentation to Townsville City Council

Reviewed results for Moreton Bay and agreed on sites for Townsville Region

Positive response and interest in how other LGs are adopting the audit results

Table 8 Consultation activities with industry, research organisations and national bodies

Organisation

Presentation / briefing Comments

Australian Society for Fish Biology National Conference, September 2010, Melbourne

Participation in workshops and technical discussion

Greater awareness of climate vulnerability and its implications; formal presentation of changes to fish, fisheries and habitats to date (MAFR 2011)

National Seachange Taskforce

March 2011 – Presentation to the inaugural Australian Coastal Research Forum, Torquay, Victoria

Positive response to presentation – coastal local governments nationally seeking local information for adaptation to climate change SLR

Input provided to the National Seachange Taskforce Coastal Policy (Sept 2009)

Invitation to provide an update on project outcomes to 2012 conference, not taken up

34th International Symposium on Remote Sensing of the Environment

April 2011 – Presentation on methodology to international audience

Opportunity to discuss methodology with peers

Use of audits as visualisation tool for end users well received

Innovative application of spatial analysis

QCCCE / DAFF Steering Committee

July 2011 – Presentation to CQAI Steering Committee

April 2012 – Presentation to CQAI Steering Committee

Committee was impressed with project progress and outcomes, methodology, stakeholder engagement

Acknowledged that the project has provided very practical information and tools


25

Organisation Presentation / briefing Comments

NSW Fisheries

August 2011 - Briefing to NSW Fisheries Fish Habitat Managers

Strong interest in results and methodology used.

Scope for use in NSW estuaries, building on baseline marine plant mapping

NQ Dry Tropics

August 2011 – Presentation to NQ Dry Tropics in Townsville

Agreed on sites to audit in Townsville region

Positive response to methodology and outcomes from Moreton Bay audits

GBRMPA August 2011 – Met with Rachel Pears and ECOTF workshop

Links with GBRMPA climate change adaptation project for trawl industry

Fishing Industry November 2011 – Met with Eric Perez (QSIA)

December 2011 – Met with John Page and David Sterling (MBSIA)

Positive response to briefing and visualisation of impacts of SLR on fish habitats

Provided insight to adaptation issues for certain fishing methods (tunnel netting)

7. Related habitat vulnerability projects

7.1 University of Queensland SLR modelling project Julian O’Mara from the University of Queensland undertook a related project - Sea Level Rise and Landscape Changes in Intertidal Wetlands (2012, unpublished) as an honours project. This adapted the SLAMM to inform on changes to the diversity and zonation of plant species and community structure within tidal fish habitats from changes to tidal inundation and sedimentation regimes from SLR. The project produced the Model 3 outputs and maps (see Appendix 3) for each of the Moreton Bay sites. Model 3 included elevation, erosion and accretion data for Moreton Bay derived from a study undertaken by Lovelock et al (2011) who investigated the role of elevation processes in keeping pace with SLR in mangrove and saltmarsh communities. Elevation rates varied with position in the tidal zone, local mean sea level, substrate type (sandy vs mud) and level of subsidence. Two rates (low and high accretion) of surface elevations (SE) were determined and applied. High SE was 5.9 mm/year for lower intertidal and 1.9 mm/year for upper intertidal; low SE was 1.4 mm/year for lower intertidal and 0.3 mm/y for upper intertidal.

While both the western and eastern sides of the bay had similar accretion rates of 7 - 9 mm/year, the western side of the bay was found to have a subsidence rate of approximately 8 mm/year, possibly due to compaction of organic sediments. With SLR occurring at approximately 2 mm/year, the mangrove forests in the lower intertidal on the western side of the bay are highly vulnerable to the impacts of predicted SLR (Lovelock et al 2011). Accretion reduces these impacts.

For Model 3, 19 vegetation types were adapted for use in SLAMM. The 19 vegetation types were grouped into four zones for ease of interpretation. The vegetation mapping and description used for SLAMM were based on the vegetation map units reported by Dowling and Stephens (1998).


26

For SLAMM, the adopted vegetation types for the marine plant zone are listed in Table 9 below (O’Mara 2011). For example, in SLAMM:

Lower intertidal = mangrove lower: 1B Avicennia communities & 1E Rhizophora communities

Upper intertidal = mangrove upper: all other mangrove communities in map unit 1(1A, 1C, 1D, 1F) (map units 1B etc from Dowling & Stephens 1998).

Table 9 SLAMM adapted vegetation and wetland types (19 categories) and zones

Zone Adapted vegetation type (from SLAMM)

Terrestrial zone Urban area

Natural vegetation

Adjacent zone Melaleuca 7AF

Sedgelands 6B, 6C, 6D

Grasslands4B, 4C, 4D

Sedgelands 6A Casuarina 5A, 5B, 5C

Marine plant zone Sporobolus grassland 4A(i)

Claypan 2 Samphire 3A

Mangrove upper all except 1B (i), 1 E (i)

Mangrove lower 1B (i), 1 E (i) Aquatic & beach Melaleuca riverine (7B(i), 7C(iv))

Inland water

Riverine water

Estuarine water

Estuarine beach

Tidal flats

Tidal creek

Beach

Ocean

7.2 Queensland Herbarium project The Queensland Herbarium (Dowling, 2010) has commenced a related mapping and monitoring project - Monitoring Mangrove and Associated Communities in Moreton Bay, Southeast Queensland. This project is establishing 20 sites for the monitoring and mapping of mangrove and associated marine plant communities to document past and ongoing changes based on over 70 years of information. This project will document community diversity changes long-term. Currently, 10 (50%) of the long-term base-plot monitoring sites have been established. The project is made up of two parts:

1. a mapping component including an automated change detection component, and

2. a Permanent Base Plot monitoring component.


27

The aim of the project is to determine and document changes in the inter-tidal mangrove and saltmarsh communities over time to provide accurate assessments of mangrove and associated communities and their dynamics. These communities are essential as habitats for fisheries production as well as for coastal and marine health. These habitats are vulnerable to effects from adjacent onshore developments (anthropogenic) as well as natural causes such as siltation and tidal changes. Monitoring will provide a means to assess the natural versus the anthropogenic effects on the mangrove and associated marine plant communities. The sites and their locations have been assessed against 1950s photography and include sites that have changed over the last 60 years and sites that have been stable over this period. Selection of the sites include nine different vegetation types which are most likely to show change due to rising sea levels, climate, change and physical or anthropogenic effects (Dowling et al, 2011). The monitored communities represent 82% of the area of mangroves and associated marine plant communities within Moreton Bay. All sites are located between HAT and 1.5 m below HAT, based on contour information derived from LiDAR data. Further information on the project can be obtained from Ralph Dowling, project leader, Queensland Herbarium, Mt Coot-tha.


28

References Bell JD, Johnson, JE and Hobday, AJ (eds), 2011. Vulnerability of Tropical Pacific Fisheries to Climate Change, published by the Secretariat of the Pacific Community, Noumea, New Caledonia, 925pp. Beumer, J P, Sully, DW and Couchman, D, 2012. Fish Habitat Vulnerability Mapping in Coastal Queensland. Report 2: Townsville Region. Queensland Government, 35pp Bruinsma, C, Danaher, K, Treloar, P and Sheppard, R, 1999. Coastal Wetland Resources of the Bowen Region: Cape Upstart to Gloucester Island. Department of Primary Industries, Queensland, Brisbane, 59pp. Calogeras, C, 2012. Moreton Bay Tunnel Net Fishery Code of Best Practice, May 2012 , C-AID Consultants, 31pp. www.c-aid.com.au Danaher, K, 1995a. Marine vegetation of Cape York Peninsular. Cape York Peninsular Land Use Strategy, Office of Co-ordinator General of Queensland, Brisbane, Department of the Environment, Sport and Territories, Canberra, and Department of Primary Industries, Queensland, Brisbane, 104 pp. De Vries C, Danaher, K and Couchman, D, 2002. Summary of Coastal Wetland Communities in Queensland by Local Government Area. Information Series QI02118. Department of Primary Industries, Brisbane, 62pp. Department of Climate Change, 2009. Climate change risks to Australia’s coasts. A first pass National assessment. Australian Government, Canberra, 168pp. DCC, 2009. Pimpama Case Study – National Coastal Vulnerability Assessment Department of Climate Change, Final Report, 185pp. Department of Environment and Resource Management, 2011. Queensland Coastal Plan, Queensland Government, 106pp. www.derm.qld.gov.au/coastalplan/#document_sections Dowling, R and Accad, A, 2010. Monitoring Mangrove and Associated Communities in Moreton Bay, Southeast Queensland. Project Proposal, Queensland Herbarium Department of Environment and Resource Management, 12pp. Dowling, R and Accad, A, 2011. Monitoring Mangrove and Associated Communities in Moreton Bay, Southeast Queensland. Interim report, Queensland Herbarium Department of Environment and Resource Management, 12pp. Dowling, R and Stephens, K, 1998. Coastal Wetlands of South East Queensland Mapping and Survey, Volume 1. Department of Environment and Resource Management, Queensland Government, 222pp. Duke, NC, 2006. Australia's mangroves: the authoritative guide to Australia's mangrove plants, The University of Queensland, Brisbane, 200pp. IAN image library, Dianne Kleine, website: www.ian.umces.edu/imagelibrary/ Johns, L, 2006; 2010 (2nd edition). Field guide to common saltmarsh plants of Queensland, Department of Employment, Economic Development and Innovation, Queensland Government, 70pp.


29

http://www.c-aid.com.au/

http://www.ian.umces.edu/imagelibrary/

Johnson, JE and Marshall, PA, (editors) 2007. Climate Change and the Great Barrier Reef. Great Barrier Reef Marine Park Authority and Australian Greenhouse Office, Australia, 818pp. Knight, JM, Dale, PER, Spencer, J and Griffin, L, 2009. Exploring LiDAR data for mapping the micro-topography and tidal hydrodynamics of mangrove ecosystems: An example from southeast Queensland, Australia. Estuarine, Coastal and Shelf Science, 85(4):593-600. Ley, JA, 2005. Linking fish assemblages and attributes of mangrove estuaries in tropical Australia: criteria for regional reserves. Marine Ecology Progress Series, 305:41-57. Lovelock, CE, Bennion, V, Grinham, A and Cahoon, DR, 2011.The Role of Surface and Subsurface Processes in Keeping Pace with Sea Level Rise in Intertidal Wetlands of Moreton Bay, Queensland, Australia. Ecosystems, 14:745–757. MAFR 2011. Climate Change and Australian Aquatic Environments, Fish and Fisheries. Special Issue Marine and Freshwater Research 62 (9): 981 - 1164. Malcolm DT, Pointon SM, Manders JA and Hall IR, 2006. Acid Sulfate Soil status of selected intertidal habitats within the Caboolture River section of the Deception Bay Fish Habitat Area. Department of Natural Resources and Water, Indooroopilly, Queensland, Australia, 54pp. Meynecke, J.-O, Lee, SY and Duke, NC, 2008. Linking spatial metrics and fish catch reveal the importance of coastal wetland connectivity to inshore fisheries in Queensland, Australia. Biological Conservation, 141:981 – 996. Meynecke, J-O, 2009. Coastal habitat connectivity - implications for declared fish habitat networks in Queensland, Australia. Pacific Conservation Biology, 15(2) :96-101. Morison, A and Pears, R, 2011. Climate change vulnerability assessment for the East Coast Otter Trawl Fishery: A brief synthesis of information. Prepared for the Great Barrier Reef Marine Park Authority, Townsville, Australia, 82pp. NSW DPI Mangrove Primefact 746, May 2008. New South Wales Department of Primary Industries, 16pp. Pacific Climate Change Science Program (PCCSP), 2011. Current and future climate of Papua New Guinea. International Climate Change Adaptation Initiative, 8pp. Rogers, K (prepared by), 2011, Coastal Wetland Vulnerability to Sea Level Rise. Final Report for the Rivers and Wetlands Unit, NSW Department of Climate Change and Water, 132pp. Saintilan, S, 2009. Australian Saltmarsh Ecology, 236pp. CSIRO Publishing, Collingwood, Victoria. Walton, J.S, Manders J.A, Goulding KE, 2011. Moreton Bay Regional Council Acid Sulfate Soils - Pine Rivers Area. Department of Environment and Resource Management, Queensland, Australia. Waycott M, McKenzie LJ, Mellors JE, Ellison JC, Sheaves MT, Collier C, Schwarz A, Webb A, Johnson JE and Payri CE, 2011. Vulnerability of mangroves, seagrasses and intertidal flats in the tropical Pacific to climate change. In: Bell JD, Johnson JE and Hobday AJ (eds) (2011) Vulnerability of Tropical Pacific Fisheries and Aquaculture to Climate Change. Secretariat of the Pacific Community, Noumea, New Caledonia, pp.297 – 368.


30

Zeppel, H. 2011. Planning for climate change by Queensland Local Councils. Paper presented to the 20th NSW Coastal Conference, Tweed Heads, November 2011, 8pp. www.coastalconference.com/2011/default.asp


31

Appendix 1: Model 2 - Maps depicting the current and future extent of marine plants (mangroves and saltmarsh) for each site MB01 Coomera Island MB02 Russell Island MB03 Pannikin Island MB04 Eprapah creek MB05 Boondall Wetlands MB06 Freshwater Creek, Hays Inlet MB07 Caboolture River MB08 Ningi-Glass Mountain Creek, Pumicestone Passage Legend for sea level rise scenarios:

Pale blue – SLR Current day Yellow – SLR plus 25 cm Red – SLR plus 75 cm Dark blue – SLR plus 100 cm

The SLR plus 75 cm equates to the 80 cm at 2100 SLR scenario for the Queensland Coastal Plan. Note – All mapping (including GIS files) for each site and each SLR scenario are available through a data agreement with Fisheries Queensland.


32


33


34


35


36


37


38


39


40

Appendix 2 Fish habitat vulnerability matrix [2010] Vulnerability of Fish Habitats (Marine Plant Communities)

Impact table Management

Issue

Marine Plant movement

Marine plant community structure

Onshore / estuarine

productivity

Overall

Climate Variable

Impact Impact Impact Impact

Sea level rise

Landward – if no restrictions (+-VE) Landward – where constraints (-VE) ∑ -VE (Medium Impact) (almost certain/moderate)

Species composition (-VE) ∑ -VE (High Impact)(major/almost certain)

Food chain complexity (-VE) Fish species (-VE) ∑ - VE (Medium Impact) (likely/moderate)

Reduced distribution & diversity landward due to current constraints and lack of planning and of buffers; fish diversity to be reduced due to reduced habitat mosaic

Sea Temperature

Poleward (+VE) increased distribution ∑ +VE (Medium Impact) (almost certain/moderate)

Species composition (+VE) Higher diversity ∑ +VE (High Impact)(major/almost certain)

Food chain complexity (+VE) Fish species (+VE) ∑ + VE (Medium Impact) (likely/moderate)

Potential to have poleward expansion and increase in diversity; fish diversity has potential to increase with increased habitat mosaic

CO2

Colonisation (+VE) Growth (+VE) ∑ +VE (Medium Impact) (likely/moderate)

Growth (+VE) Detritus (+VE) ∑ +VE (Medium Impact) (likely/moderate)

Nutrients (+VE) Primary productivity (+VE) + Fish catches (+/-VE) ∑ +VE (Medium Impact) (possible/moderate)

Increase in growth rates expected, with concurrent increase in leaf litter and invertebrate fauna; possible increase in fish numbers and catches but composition of catch may change


41

Management Issue



Onshore / Overall estuarine

productivity Climate Variable

Impact Impact Impact Impact

Rainfall & Runoff

Colonisation (+VE) - salinity ; water table Mortalities (-VE) - inundation ; seed loss ; erosion ∑ -/+VE (neutral Impact)

Species composition – landward Species composition – poleward ∑ -VE (High Impact) (almost certain/major)

Nutrient flushing (+VE) Primary Production (+VE) + Fish catches (+/-VE) ∑ +VE (Medium Impact) (likely/moderate)

High rainfall frequency & lower salinity increases colonisation but countered by high erosion, extended inundation (‘drowning’) and seed loss; nutrient flushing inshore waters increased but timing will influence fish productivity

Overall estimate of

risk

Marine plants restricted in certain areas of the coast due to constrictions from built environment or landform features. Reduction in extent of landward marine plant distribution. Potential expansion poleward.

Marine plant community structure will change with mangrove communities most likely benefiting at the expense of saltmarsh communities. Biodiversity to reduce landward but increase poleward.

Increase in primary productivity if marine plants are able to move with sea level rise and increased phytoplankton blooms due to temperature, rainfall & nutrient increases. Catch composition may change to favour detritivores (e.g. mullet) and planktivores (e.g. herring)


42

Vulnerability of Fish Habitats (Marine Plant Communities)

Adaptation table Management

Issue



Onshore / estuarine

productivity

Overall

Climate Variable Adaptation Adaptation Adaptation Adaptation Sea level rise

Planning for movement Mapping & education Better planning & mapping areas of current & potential extent – limited by existing landward development -VE (High vulnerability) (High impact/Medium adaptive capacity)

Mapping / Education Costs Research -VE (High vulnerability) (High impact/Medium adaptive capacity)

Catch change – different species Markets change Costs -VE (Moderate vulnerability) (Medium impact / Medium adaptive capacity)

Marine plant communities are highly vulnerable to SLR; success of landward movements subject to rate of SLR; mapping & planning time-consuming and in need of support; changes in fish communities will be reflected in catches and marketing viability

Sea temperature

Planning for movement Mapping & education Better planning & mapping areas of current & potential extent – limited by existing poleward development -VE (Moderate vulnerability) (Medium impact/Medium adaptive capacity)

Mapping / Education Costs Research -VE (High vulnerability) (High impact/Medium adaptive capacity)

Catch change – different species Markets change Costs -VE (Moderate vulnerability) (Medium impact/Medium adaptive capacity)

Marine plant communities are moderately vulnerable to SLR ; success of poleward movements subject to rate of temperature increase; mapping & planning time-consuming and in need of support; changes in fish communities will be reflected in catches and marketing viability


43

Management Issue


Marine plant Onshore / Overall community estuarine structure productivity

Climate Variable Adaptation Adaptation Adaptation Adaptation CO2

Enhance natural colonization Growth (+VE) +VE (No vulnerability)

Enhance diversity by plantings Costs -VE (Moderate vulnerability) (Medium impact/Low adaptive capacity)

Fish diversity and catches +VE (No vulnerability)

Marine plant communities have zero or low vulnerability to CO2 changes; likely to enhance colonisation and growth and lead to increase fish productivity

Rainfall & Runoff

Planning Development in floodplain +VE (No vulnerability)

Profile tidal slopes to enhance colonisation Costs -VE (High vulnerability) (High impact/Low adaptive capacity)

+VE (No vulnerability)

Marine plant communities have little vulnerability to Rainfall and Runoff where proper planning prevents development in floodplains; cost of shaping tidal profiles to enhance colonisation likely to be unacceptable

Overall estimate of

vulnerability

High, where constraints are present landward and poleward; high costs of planning; extensive mapping (6 000 km of coastline) commitment

High (costs of intervention strategies)

Moderate (market adjustment & consumer acceptance); promotion of catch changes; training costs; gear cost changes


44


Risk statement

the risk to the fishing sectors of losing marine plant habitats will result in changes in fisheries production and in catch composition;

this level of risk requires an urgent response from senior levels of industry and from local, state and federal governments for policy and management; and

the risk can be mitigated through provision of retreat areas for marine plant habitats through strategic planning instruments at local and state government levels and through fishing sectors adapting catch and marketing strategies for changes in catch composition.


Way forward select key sites that are audited in terms of current marine plant distributions and their

diversity;

selected sites to reflect different coastal areas where low, medium and high levels of development (i.e. potential barriers);

develop several scenarios of SLR and map and audit likely changes in marine plant distributions and diversity; and

liaise with key stakeholders, e.g. local governments, to ensure that planning instruments consider future marine plant communities and by definition, future fish communities and catching of these.


45

Appendix 3 SLAMM Model 3 project summary & map outputs SLR and Landscape changes in Intertidal Wetlands Project summary Intertidal wetlands provide a range of ecosystem services including the provision of fish habitat, coastal protection, nutrient and carbon sequestration and cycling (Alongi, 2002; Duke et al., 2007; Lovelock, 2008). Worldwide intertidal wetlands are threatened by urban development, aquaculture, mining and over-exploitation (Alongi, 2002). Climate change also poses threats to intertidal wetlands due to changes in atmospheric CO2 concentrations, temperature, precipitation and sea level rise (SLR) (Pratchett et al., 2011; Gilman et al., 2008). Sea level rises (SLR) resulting from climate change has been identified by numerous studies as the factor that will have the greatest influence on the present extent and adaptive capacity of intertidal wetlands (Morris et al., 2002; Lovelock et al., 2011; Lovelock & Ellison, 2007; Nicholls, 2004; Gilman et al., 2007). The direct impacts of (SLR) on intertidal wetland vegetation include increased tidal frequency, depth and duration of tidal inundation, changes in sedimentation and nutrient delivery regimes and alterations to species interactions. These factors interact with anthropogenic influences, particularly coastal development, to threaten coastal wetlands (Gilman et al., 2008; Lovelock et al., 2011; Pratchett et al., 2011). Aims & Methodology This study has investigated how SLR will affect the distribution of intertidal wetlands in Moreton Bay, Queensland. To assess changes in intertidal wetlands, the Sea Level Affecting Marshes Model (SLAMM) was used. SLAMM simulates the dominant processes involved in intertidal wetland conversions in response to long-term SLR (Craft et al., 2009). One of the observed changes in coastal wetlands that has been attributed to SLR is the invasion of salt marsh by mangroves (Saintilan & Williams, 1999; Rogers, 2005). Here I have endeavored to further the understanding of mangrove migration into salt marsh habitats by testing the effects of a number of key driving pressures that have been proposed to facilitate the invasion of salt marsh habitats by mangroves. In addition to changes in the area of intertidal wetlands, the arrangement of wetlands in the landscape may also change with SLR (Bernhardt & Willard, 2011), resulting in a loss of habitat for bird species, turtles and fish (Galbraith et al., 2002; Fuentes et al., 2010; Loneragan et al., 2003). These changes may affect the commercial and recreational fishing industries that depend on mangrove and salt marsh habitats (Beck et al., 2001; Koehn et al., 2011). The future landscapes generated in SLAMM and a range of landscape indices that have been positively related to fish abundances were used to assess how changes to the spatial arrangement of wetlands may alter the value of fish habitat located in Moreton Bay in the future. Results Key results from the SLAMM analysis showed the rate of change and composition of wetland vegetation by the year 2100 was dependent on the rate and magnitude of SLR. At moderate rates of SLR (0.567 – 0.671 m) the total area of wetlands increased by 45-51% and under high SLR (1.79 m by 2100) the extent of intertidal wetlands increased by 41%, compared to the area of wetlands in the year 2000. Assessment of vegetation change over time indicated that rates of change in vegetation extent were significantly different between the time periods of 2000-2050 and 2050-2100. Losses in low intertidal mangroves and salt marsh vegetation were particularly apparent between 2050 and 2100 for the 1.79 m scenario (Mangrove lower r2=0.255, p=<0.02; salt marsh r2=0.284, p=<0.01).


46

The experimental component of this study exploring how SLR related pressures contribute to the landward migration of mangroves into salt marsh, found that the imposed pressures differentially affected the growth rate of mangrove seedlings within salt marsh. In particular changes to salt marsh – mangrove competition resulted in significant increased growth of mangrove seedlings within the salt marsh. In brief, this indicates that if salt marsh is in a degraded state, mangroves will more easily migrate landward and the rate at which salt marsh areas are lost will increase. Analysis of metrics associated with the quantity and quality of fish habitat indicated that as the magnitude of SLR increases, fish habitat condition within Moreton Bay will improve. All three metrics measured indicate improvements as the rate of SLR increases in the future:

wetland extent will increase as the magnitude of SLR increases, increasing available habitat;

seaward mangrove perimeter increases as the rate of SLR increases. Resulting in a greater area of available habitat at the seaward edge of the wetland, increasing the area for fish to forage for food and provide protection against predation; and

increased connectivity between intertidal and subtidal (sea grass) habitats. Improving connectivity is seen as beneficial for fish populations dependent on spatially connected habitats.

Study outcomes This study has demonstrated that intertidal wetlands are predicted to experience significant spatial rearrangements in the future as a result of SLR. Most prominently mangroves will migrate landward, increasing the overall area of mangroves within the intertidal. As a result of this migration the salt marsh component of intertidal wetlands are likely to diminish greatly in size, this will impact species and processes dependent on salt marsh habitats. Identification of this potential change positions us to better manage these habitats knowing how they will respond to SLR. Through changing management practices we are able to improve the adaptive capacity of intertidal wetlands to deal with SLR, and by taking a long-term approach we can reduce other pressures (e.g. new developments) likely to further degrade these ecosystems. As a result of identifying potential improvements of fish habitat under SLR, we are able to improve the way in which we utilise and manage these areas in the future. Through identifying changes in the spatial arrangement of wetlands we can, if necessary, alter fishing methods and target species to better manage future impacts on wetlands and their dependent species. This information will prove useful to those who inform policy and management of these areas and the resources they provide. While many of the world’s intertidal wetlands are being increasingly degraded (Alongi, 2002), in Australia we still have many healthy wetlands. By taking pre-emptive action and putting in place plans to improve the adaptive capacity of wetlands, it is possible to provide adequate lead time to ensure the continuation of ecosystem services and provide an opportunity to adaptively manage SLR over the long-term rather than responding with ad-hoc measures unlikely to result in a beneficial outcome (Gilman et al., 2008). This research has identified numerous implications for intertidal wetlands that will arise as a result of SLR. Results of this study provide a basis for both management actions and future directions for research that will improve upon the outcomes of this study.


47


48

For complete study details and references see the complete thesis. The following maps indicate the vegetation types and area included in the SLAMM assessment. Maps were produced for each of the four SLR scenarios. A subset of the maps are included in this Appendix and indicate current day marine vegetation distribution with the Model 2 area mapped overlay and maps indicating the 1 m SLR at 2100 at low and high elevation rates for each site in Moreton Bay. It is important to note that the ‘box’ that was mapped for SLAMM for each site is different in area to that mapped for Model 2. In undertaking the mapping and audit calculations for Model 2, a discrete wetland system was mapped which is a subset of the total area covered by the SLAMM calculations. SLAMM intertidal vegetation at current (baseline) and at 2100, 1. m SLR: MB01 Coomera Island

MB02 Russell Island


MB04 Eprapah Creek


MB06 Caboolture River

MB07 Freshwater Creek

MB08 Ningi-Glass Mountain Creeks

MB01 SLAMM output, Coomera Island

Fish habitat vulnerability mapping in coastal Queensland Moreton Bay region 49

MB02 SLAMM output North west Russell Island


50

MB03 SLAMM output Pannikin Island


51

MB04 SLAMM output North West Eprapah Creek


52

MB05 SLAMM output Boondall Wetlands


53

MB06 SLAMM output Freshwater Creek


54

MB07 SLAMM output Caboolture River


55

MB08 SLAMM output Ningi-Glass Mountain Creeks


56

Documents

Fish habitat vulnerability mapping in coastal …...Fish habitat vulnerability mapping in coastal Queensland Moreton Bay region vii The audit has been applied to approximately one