Case studies

The ability to map shorelines through time provides valuable insights into whether changes to Australia’s coastline are the result of specific events or actions, or processes of more gradual change over time. This information can enable scientists, managers and policy-makers to assess the effects of the drivers impacting our coastlines, and potentially aid planning and forecasting for future scenarios.

Digital Earth Australia (DEA) Coastlines (GA 2021) is a continental dataset that includes annual shorelines and rates of coastal change along the entire Australian coastline from 1988 to the present. DEA Coastlines combines satellite data from Geoscience Australia’s DEA program (Dhu et al. 2017, Lewis et al. 2017) with tidal modelling to map the dominant position of the shoreline at mean sea level tide each year. DEA Coastlines allows trends of coastal erosion and growth to be examined at both local and continental scales, and for patterns of coastal change to be mapped historically and updated regularly as data continues to be acquired. This allows current rates of coastal change to be compared with those observed in previous years or decades.

The 33-year DEA Coastlines record provides new insights into patterns and processes of coastal change across the entire Australian coastline. At a national scale, 22% of Australia’s nonrocky coastlines have retreated or grown significantly since 1988, with 78% remaining net stable over this time (Table 2) (Bishop-Taylor et al. 2021). Trends of retreat and growth were closely balanced across Australia over the past 3 decades, despite strong regional variability and extreme local hotspots of coastal change – for example, point 1 in Figure 7.

At a local scale, DEA Coastlines can be used to better understand the complex coastal processes occurring at these hotspots of coastal change. For example, on Australia’s wave-dominated coasts, coastal barriers and lagoons are threatened by the influence of relative sea level rise, altered storm systems and other climatic effects (Nanson et al. 2022). Barrier responses are likely to vary between regions, and detailed analyses of historical barrier dynamics can help to inform their management.

Figure 8 presents 2 examples of how DEA Coastlines can provide insights into historical erosion impacting coastal lagoon barriers. Figure 8a shows that that changes at Southport Lagoon are all negative, indicating sand loss, with losses of around 2 m being most common, apart from 0 m. Figure 8b shows the lagoon; the area in the white box is shown in more detail in Figure 8c. Figure 8d traces the barrier width over time, measured along the white dotted line in Figure 8c. Figures 8e–h give similar results for Bribie Island – again, the barrier is thinning.

These long-term insights can be used to aid management of these affected ecosystems and population centres, complementing coastal monitoring data from existing state and local government programs.

Figure 7 Three decades of coastal change across Australia based on the satellite-derived Digital Earth Australia Coastlines dataset

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Figure 7 Three decades of coastal change across Australia based on the satellite-derived Digital Earth Australia Coastlines dataset

Source: Bishop-Taylor et al. (2021)

Figure 8 Evolution of width of sand features at Southport Lagoon (Tasmania) and Bribie Island (Queensland), 1988 to 2018

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Figure 8 Evolution of width of sand features at Southport Lagoon (Tasmania) and Bribie Island (Queensland), 1988 to 2018

Source: Nanson et al. (2022)

Much knowledge of the changing landscapes of Australia has come from multitemporal Earth observations over at least the past 50 years. However, interpreting and consistently quantifying the extent of land covers and ecosystems across Australia from Earth observation data has proved a significant challenge that has required major investment in research and development and capacity for ground data collection (Jackson & Rankin 2017). Australia’s Terrestrial Environment Research Network (TERN) has played a large role in data integration, building cross-institutional collaborations, facilitating the sharing of infrastructure and providing open access to data.

TERN has focused on developing information systems that give access to data and knowledge, thereby ensuring a better understanding of ecosystems and environments. The TERN Mangrove Portal (Lymburner et al. 2020) shows how disparate environmental data can be collected and collated to support the development of mangrove monitoring (Figure 13).

Through a joint effort by Geoscience Australia and TERN, 25-metre-spatial-resolution maps of mangrove extent by canopy cover type (open woodland, open and closed) have been generated annually (1986–2016), Australia-wide, using dense timeseries of satellite data held within the Digital Earth Australia platform (Lymburner et al. 2020) (Figure 14). These maps show the annual dynamics of mangroves across Australia and provide better information on impacts of change (e.g. dieback) due to environmental and anthropic pressures, including those related to climate (e.g. sea level rise and changes in storm positions, frequencies and intensities), and ultimately better inform options for mangrove management. The timeseries shows that Australia’s mangroves expanded between 1992 and 2010 and contracted thereafter.

The mangrove portal was developed primarily because the 2015–16 dieback event across the northern coastline showed the need for a mangrove monitoring system. Dieback resulted in the death of more than 7,000 hectares (ha) of mangroves (Duke 2017) over several months. Such an event was unexpected given that previous remote-sensing observations had reported a steady landward and seaward expansion of mangroves along sections of this coastline since 1985 (Asbridge et al. 2016). Due to the area’s remoteness, the dieback was first discovered by fishermen and scientists conducting unrelated fieldwork. The discovery and reporting of the event, which included uncertainties around the real area lost to dieback (initial estimations cited over 10,000 ha), exposed the need for ongoing monitoring to establish the extent and distribution of changes in ecosystem condition, support prioritisation of interventions, and monitor trends (e.g. recovery, ongoing degradation, stable conditions).

A major benefit of the TERN Mangrove Portal is that it provides multiple openly available datasets relevant to mangroves (including those affected by the dieback event), which assist not only with the development of a monitoring system, but also support scientific research, the conservation, management and sustainable use of mangroves, policy development, and evaluation management actions (Lucas et al. 2017, Metternicht et al. 2018).

The mangrove portal shows the potential of data integration (satellite, drones, airborne, historical aerial photographs, field data) to advance understanding and identify knowledge gaps. It also highlights that datasets and products need to be open access and easily discoverable to inform policy and enable coordinated scientific research. A wide and diverse range of datasets are available through the portal, and capacity exists for continual upload of new and existing datasets.

Figure 13 Conceptual framework of a mangrove monitoring system responding to policy and monitoring needs

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Figure 13 Conceptual framework of a mangrove monitoring system responding to policy and monitoring needs

Note: © 2018 IEEE. Reprinted, with permission, from Metternicht G, Lucas R, Bunting P, Held A, Lymburner L & Ticehurst C (2018). Addressing mangrove protection in Australia: the contribution of earth observation technologies. In: IGARSS 2018 – 2018 IEEE International Geoscience and Remote Sensing Symposium, Valencia, Spain, IEEE, 6548–6551.

Source: Metternicht et al. (2018)

Figure 14 Extent of mangroves in Australia in 2017, using data integration from satellite, airborne and field observations

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Figure 14 Extent of mangroves in Australia in 2017, using data integration from satellite, airborne and field observations

ha = hectare; km = kilometre

Source: Lymburner et al. (2020)

As a nation surrounded by large stretches of high-value sandy coastlines, Australia faces a constant threat of marine hazards. Extreme events, such as coastal storms and tsunamis, can have severe consequences along the open coastline, including wave overtopping (where waves go over the top of a coastal structure such as a seawall), marine coastal flooding and beach erosion. Marine hazards pose significant risks to life and livelihoods, property, critical systems and infrastructure, marine economic and recreation activity, and ecosystems. In the future, these risks may be exacerbated as socio-economic activity continues to grow within coastal regions and as the effects of climate change increase (Middlemann 2007).

Early warning systems are an integral part of coastal risk reduction strategies. In the days to hours ahead of an approaching event, early warning systems provide critical information about coastal hazards that may occur during the event, such as the predicted beach erosion and the predicted oceanic inundation of low-lying coastal land. Clear and timely information helps civil protection agencies minimise the risk posed to coastal communities and assets. Globally, well-developed and well-placed coastal early warning systems are credited with significantly reducing mortality rates due to extreme events (World Bank & United Nations 2010).

Such systems are also highly cost-effective. In the United States alone, early warning systems for weather- and water-related hazards deliver a total estimated value of US$31.5 billion per year, which far surpasses the estimated cost of developing and maintaining these systems (US$5.1 billion) (Lazo et al. 2009).

Australia has established systems aimed at forecasting coastal hazards. The Australian Bureau of Meteorology (BOM) operates an early warning system for tropical cyclones and associated storm tides, issuing watches and warnings up to 2 days ahead of cyclone landfall. In addition, advisories are issued for anomalously high tides or damaging waves caused by mid-latitude storms (including east coast lows) and other low-pressure systems.

Early warning and forecasts are also provided for tsunami events. Following the devasting impacts of the 2004 Indian Ocean Tsunami, the Joint Australian Tsunami Warning Centre (operated by BOM and Geoscience Australia) was established to provide continuous monitoring and to issue real-time alerts for tsunami events that pose a threat to Australian coastal zones and offshore territories (Allen & Greenslade 2010).

These systems distribute high-quality information to end users, who report high levels of satisfaction with BOM’s current level of service ahead of extreme events (Munro 2011).

However, despite concerted efforts directed towards developing and implementing coastal early warning systems, gaps remain within the nation’s current operational capacity. Importantly, no operational system currently accounts for the widespread and costly problem of coastal erosion (DCCEE 2011). Beach erosion hazards have featured prominently along Australia’s densely populated, wave-dominated coastlines (e.g. the New South Wales coastline), where several recent, prominent east coast low events (2007, 2016, 2020; see Figure 23) have renewed attention on, and urgency towards, improving erosion hazard forecasting. Currently, civil authorities rely on meteorological observations and forecasts to assess potential erosion impacts to the coast, but these forecasts do not directly predict erosion.

A pilot early warning system is being developed that accounts for both marine flooding and erosion hazards along Australia’s coast. It is being developed through a partnership between the University of New South Wales, University of Western Australia, local- and state-level government agencies, and the Australian Research Council. The system is built upon best practices developed for similar systems globally (Stockdon et al. 2012, Harley et al. 2016), but is adapted for Australia’s high-energy, wave-dominated coastlines. These new systems follow a tiered approach, providing rapid warnings for flooding and erosion hazards at regional scales, as well as more detailed erosion predictions at high-risk local sites. Testing and evaluation are in progress to assess the accuracy and efficacy of the warnings generated by this pilot system along both the eastern and western coasts of Australia.

The diversity and pervasiveness of Australia’s coastal hazards highlight a need to establish a nationwide multihazard coastal early warning system. Many essential forecasting products, which would form the foundation of such a system, are already up and running. However, targeted development efforts are further needed to extend upon Australia’s state-of-the-art forecasting capacity to produce forecasts that meet the needs of Australia’s coastal communities. These efforts, along with continuously raising the public’s awareness of coastal hazards, will further empower end users and communities to make critical and timely decisions to protect life, property, and critical economic and environmental systems.

Figure 23 The 2020 east coast low at Narrabeen Beach (New South Wales)

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Figure 23 The 2020 east coast low at Narrabeen Beach (New South Wales)

Photo: Mitchell Harley

Sharks provoke both fear and wonder. In Australia, shark-bite incidents are high profile, prompting media and government responses. However, risk of shark bite is small. Approximately 1.2 people per year were killed due to shark bite over the 30 years from 1990 to 2019 (West 2011, TCSA 2021). In comparison, Australia saw on average 110 coastal drowning deaths per year over the 15 years from 2004 to 2019 (SLSA 2020).

There are more than 400 shark species living today, but only a few pose a threat to people. Just 3 account for most of the interactions that result in harm to people: the great white shark (Carcharodon carcharias), the tiger shark (Galeocerdo cuvier) and the bull shark (Carcharhinus leucas). Some other whaler species (Carcharhinus spp.) are also known to cause harm to people. However, species identified as potentially dangerous do not always cause harm (Gibbs & Warren 2015, Chapman 2017), and sharks are not inherently dangerous. People encounter sharks often with no negative consequences. Interactions may be organised or incidental, with one of the many species that pose no threat or little threat to people, or with potentially dangerous species.

Many shark species are threatened by pressures from human activity, mainly habitat degradation and unsustainable fishing (Dulvy et al. 2014, IPCC 2014, United Nations 2017). The 3 potentially threatening shark species are recognised as Threatened or Near Threatened by international and state institutions, including the International Union for Conservation of Nature and the Australian Environment Protection and Biodiversity Conservation Act 1999.

A variety of strategies are in place, in Australia and around the world, to protect people from the risk of shark bite. Two prominent methods used in Australia are often lethal to sharks and other marine life: shark nets or mesh (large-mesh gillnets anchored near popular beaches), and drumlines (baited hooks anchored to the seabed and a floating drum). Nontarget species (bycatch) consistently represent a substantial proportion of animals caught and killed in Australia’s major shark hazard management programs (Krogh & Reid 1996, NSW DPI 2020).

The New South Wales Shark Meshing (Bather Protection) Program is the world’s longest-running lethal shark hazard management program, introduced in 1937 (Reid et al. 2011). It aims to reduce the threat of shark interactions while minimising impacts on nontarget species (NSW DPI 2020). However, the program was identified by the NSW Office of Environment and Heritage as a key threatening process due to its impacts on both target and nontarget species (NSW OEH 2011).

Research, innovation and interest in developing nonlethal technologies are growing rapidly, in line with changing public attitudes and ethics towards sharks and the ocean. Such strategies include observation, exclusion barriers, spatial deterrents and personal deterrents (Adams et al. 2020b, McPhee et al. 2021). No single technology is appropriate for all contexts, as each method is suited to different coastal landscapes, ocean activities and shark species. Beach patrol, combined with effective emergency response and medical treatment, has been shown to contribute significantly to reducing fatalities from shark bite (Gibbs et al. 2020). Continued investment in these areas is essential for improving beach and ocean safety related to shark bite and other accidents. Australia is on the cusp of shifting the way that shark risk and conservation are understood and managed. Creative models for co-existence will lead to positive effects for people, sharks, and other marine life and ecosystems.

Approximately 423,000 square kilometres of land drains to the Great Barrier Reef (GBR) lagoon, all of which can be a potential source of pollutants entering the lagoon. Uses of this land include cattle grazing (72% of the area); conservation (15%); other agriculture (5.8%); forestry (4.6%); mines, wastewater treatment plants, land-fills, and industrial and commercial sites (2.4%); and residences of 1.2 million people (0.3%) (ABS 2017, DES 2020). However, the composition of land uses is highly variable at different spatial scales.

Currently there are more than 40,000 industrial chemicals (Wang et al. 2020) and 9,500 pesticides (APVMA 2021) registered for use in Australia. Where these chemicals are used and disposed of, and their physicochemical properties (e.g. solubility in water) will determine where they end up in the environment (e.g. soil, sediment, water, biota). Kroon et al. (Kroon et al. 2020) recently identified antifouling paints, coal dust, metals, metalloids, marine debris, pharmaceuticals, personal care products and petroleum hydrocarbons as chemicals of emerging concern for GBR waters, but stated that the available monitoring data were insufficient to permit risk assessments. Consistent with this, Heffernan et al. (Heffernan et al. 2017) detected more than 5,000 organic chemicals in green turtle blood collected at 3 sites in the GBR lagoon. An extensive database of the annual amounts of suspended solids and nutrients and the concentration of approximately 60 pesticides entering the lagoon over 10 years has been generated. Other chemicals have been monitored on an ad hoc basis.

By 2015, 56 pesticides had been detected in GBR catchment and marine ecosystems (Smith et al. 2015), and 80% of samples collected between 2010–11 and 2014–15 contained mixtures of up to 20 pesticides (Warne et al. 2020b). Twenty-two pesticides were frequently detected in waters entering the lagoon (Warne et al. 2020a). By accounting for the concentration and temporal exposure of these 22 pesticides, it was estimated that less than 1% to 30% of aquatic organisms would experience harmful effects at the mouths of waterways entering the lagoon from 2015–16 to 2018–19. The greatest risk occurred in waterways of the Mackay–Whitsunday region (Warne et al. 2020a, Water Quality & Investigations 2020).

The pesticide risk condition on the 2019 Reef Water Quality Report Card for the GBR indicates that 97.2% of aquatic species across all GBR catchments were unlikely to experience harmful effects from pesticides (Queensland Government 2019). However, this represents the spatially averaged risk, and some regions and catchments are much more exposed than others. Inshore monitoring of 22 pesticides in 2018–19 revealed that 7 of 11 sites met the desired level of protection for the GBR (i.e. more than 99% of aquatic species) (Thai et al. 2020). In parts of the GBR lagoon not affected by flood plumes, the risk from these 22 pesticides is likely to be very low. However, current risk assessments only consider 22 pesticides and do not consider co-stressors, such as heatwaves, which can increase the risk posed to aquatic species (Negri et al. 2019), the lifelong exposure of organisms to very low pesticide concentrations and the toxicity of most breakdown products.

Ecological (eco-) engineering in urbanised marine environments is a growing field with global significance (Chapman et al. 2018). The term describes how ecological understanding can be combined with engineering principles to mitigate the ecological impacts of artificial structures (Bergen et al. 2001). In Australia, efforts to ecologically engineer artificial structures have so far focused on intertidal seawalls and have been supported by more than 20 years of experimental research (Chapman et al. 2018). Three strategies have dominated:

• using sloped or stepped (instead of vertical) designs to increase habitat availability
• adding complexity that provides protection to inhabitants from predators and environmental stressors, and increases surface area for attachment (reviewed by Strain et al. (2018))
• adding different types of habitat to provide a greater variety of environmental conditions for different species (reviewed by Chapman & Underwood (2011)).

Barangaroo Reserve is a recent example in Sydney Harbour where the first 2 strategies have been applied to the design of a new seawall as part of an urban renewal project. The project replaced a vertical concrete seawall, artificially aligned to suit commercial shipping and industrial purposes, with 1.4 kilometres of stepped sandstone blocks that followed the historical natural shoreline alignment of headland and coves. The sandstone was locally sourced from the adjacent escarpment, with the 9,315 sandstone blocks cut so they varied in size and shape. Use of heterogeneous blocks in a stepped design increased the intertidal area for marine species to colonise and created crevices where species such as oysters, snails, limpets and chitons could be protected from predators and environmental stressors. The stepped design also enabled people to access the marine environment and interact with its biodiversity. After block placement, natural weathering formed small rock pools that support filamentous green and brown as well as coralline algae.

The project was designed following government guidelines (Wiecek 2009) and with input from marine experts from the New South Wales Department of Planning, Industry and Environment and Kogarah Council. It also benefited from computer modelling that was used to individually design and cut blocks for the location.

There are also a growing number of examples in Sydney Harbour where the strategies listed above have been applied to increase the biodiversity of existing seawalls. Early studies drilled or excavated pits and crevices into seawalls (Chapman & Underwood 2011), enhancing rates of colonisation of species, though not necessarily of missing target species. Based on the learnings from this early eco-engineering, purpose-built water-retaining features were subsequently developed, which support species of algae, invertebrates and cryptic fish that would not otherwise be associated with seawalls (Browne & Chapman 2014, Morris et al. 2018). Advances in 3D design and printing have also provided new opportunities to incorporate more complex topographic features of natural habitats, such as rock pools, crevices and root structure, into seawalls. Small-scale pilot projects, using complex tiles fitted to seawalls, demonstrated the efficacy of topographic complexity in enhancing native species biodiversity (Ushiama et al. 2019, Strain et al. 2020), although the extent of benefits vary by location, the type of complexity provided and the scale of habitat modification (Strain et al. 2018). These pioneering studies have provided proof-of-concept for scaling up eco-engineering to entire seawalls.

The Living Seawalls project has developed a method of enhancing the topographic complexity of entire seawalls using concrete habitat modules. Modules are fabricated from moulds produced using the latest 3D printing technology and come in a range of designs that mimic habitat features such as rock pools, fish hollows, kelp holdfasts, sponge fingers and mangrove roots. Modules can be customised to locations and arranged in habitat mosaics, to maximise benefits to a wide range of species.

Mosaics of modules have been applied at scale to 9 seawalls in Sydney Harbour including Milsons Point, Sawmillers Reserve, Rushcutters Bay, Balmain East, Barangaroo, Fairlight and Clontarf. More than 900 habitat modules have now been installed since the first installation in October 2018.

Within hours of installation the modules are inhabited by microscopic life and invertebrates, and in just a few months, the modules are crowded with marine life. Colonisation of the modules by fish, invertebrates and algae is being monitored over several years to document how these installations benefit humans and marine life alike. Fundamental and applied research projects in this area are essential for the future management of artificial structures in the marine environment. The success of eco-engineering depends on multidisciplinary collaboration among ecologists, engineers, architects, developers, social scientists and other stakeholders, so that engineering, ecological and social goals may be simultaneously met.

Evolution and speciation were historically thought of as processes that happen over geological time. However, it has recently become clear that plant and animal species can undergo substantial evolutionary change within just a few years or decades. Introduced species are particularly likely to undergo rapid evolutionary change, as they experience different environmental conditions and interact with a suite of different species when they arrive in a new country. In fact, a study of 23 plant species introduced to New South Wales in the past 150 years or so found that 70% had undergone significant morphological change since their arrival (Buswell et al. 2011).

Rapid evolution can allow invasive species to spread more effectively in their new ranges. For example, cane toads in Australia have evolved longer legs and hop in straighter lines, which results in much greater dispersal speeds and an exponential increase in the rate of range expansion (Phillips et al. 2006).

Rapid evolution can also allow invasive species to change their morphology, physiology and reproductive biology to become better adapted to survive in Australian conditions. An example of this is Arctotheca populifolia, a beach daisy introduced to Australia from South Africa in the 1930s (Figure 32). A. populifolia has changed its growth form and leaf shape (Brandenburger et al. 2019b), photosynthetic rate, and water use efficiency (Brandenburger et al. 2019a) to better suit the windier, drier conditions it encounters in Australia. It has also developed self-compatibility, which allows it to produce seeds without assistance from pollinators.

Rapid evolution will likely lead to an increase in both geographic scope and impact of many plant and animal invaders over the coming decades.

Figure 32 Source and Australian plants of Arctotheca populifolia

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Figure 32 Source and Australian plants of Arctotheca populifolia

Photo: Claire Brandenburger

Dr Emma Lee, Aboriginal Research Fellow, RegionxLink programs, Centre for Social Impact, Swinburne University of Technology

Connections to sea Country are an inherent part of belonging to an island, and Aboriginal Tasmanian heritage places – such as living midden sites – comprise some of the world’s most complex, deepest and richest coastal archaeological places. Sea Country is a place of law, ancestral beings, women’s governance, food, medicine, travel and art, and has its own agency. The relationship that Aboriginal Tasmanians have with sea Country is holistic and creates wellbeing in all parts of our lives.

Since 2018, members of the Tasmanian Regional Aboriginal Communities Alliance (TRACA) have co-created a research project with Swinburne University of Technology to establish a market for cultural fisheries. Cultural fisheries are any engagement by an Indigenous person in fisheries that brings benefit to Indigenous communities and integrates Indigenous knowledges in modern settings; it is not gear-dependent but oriented towards reimagining social justice as regional development.

This model looks to transform the Tasmanian commercial abalone sector from a profit focus to that influenced by Indigenous-led social impact outcomes. In devising the program of works by TRACA members, the establishment of a market for cultural fisheries will aim to end juvenile justice interventions and provide the means through which Aboriginal Tasmanian families can re-connect to sea Country as a ‘cradle to grave’ program of young peoples’ cultural wellbeing.

Across 2019–20, TRACA have come together with government agencies including fisheries, Aboriginal Affairs and community services, as well as aquaculture, hospitality, education, training and marketing collaborations, to build a business case for cultural fisheries. The Indigenous Land and Sea Corporation (ILSC) and the University of Tasmania are working with TRACA to investigate using government-held abalone quota to advance social justice aims. In delivering Indigenous wild-catch seafoods to local restaurants in Tasmania, Aboriginal Tasmanians can provide unique provenance and sustainability that grows consumer choice while expanding engagement opportunities for young people.

During Tasmanian state elections in May 2021, both major parties supported establishing cultural fisheries as a campaign commitment. The business case for ILSC includes social impact indicators for Aboriginal Tasmanian wellbeing, and building capacity for cultural fisheries through multiple, collegial partnerships with government, research, business and Aboriginal organisations. Regional development for Aboriginal Tasmanians is not a singular focus on economic growth, but rather a means to integrate the diverse cultural and holistic needs of building and maintaining connections to sea Country.

In creating future conditions of cultural security, safety and belonging for Aboriginal Tasmanian children that remove the need for a juvenile justice system to even exist, the program of establishing cultural fisheries reflects the complex and plural connections to sea Country. Commercial fisheries alone cannot deliver cultural satisfaction in managing sea Country; hence, TRACA plans to centre both cultural and community benefits to transform social impacts of regional development through Indigenous-led research.

Falen D Passi, Mer Gedkem Le Registered Native Title Bodies Corporate Chair with Vic McGrath, Torres Strait Regional Authority Land and Sea Management Unit

The rich traditions of Meriam Traditional Custodians from Mer (Murray Island) in eastern Zenadth Kes (Torres Strait) encompass the traditional tamer (knowledge), cultural responsibilities and lore for looking after land and sea Country. As the wind changes across our Island, our Meriam Le (people) navigated and lived alongside nature through a deep connectedness between the 4 winds, animals, plants and our sea-faring culture. The turning of the seasons and cycle of changes in animals, plants, the 4 winds, breakers on the coral reefs, clouds, constellations, moon and tides influences when to plant, when to hunt, when to travel and when to hold our ceremonies. The importance of this Meriam traditional knowledge lies at the heart of our community aspirations to preserve our cultural knowledge and Meriam Mir (language).

Seasonal calendars are powerful tools for promoting and revitalising traditional languages and ecological knowledge, as well as recording and strengthening cultural connections between Torres Strait Islanders and their islands and sea Country. Working in close collaboration with the Torres Strait Regional Authority’s (TSRA’s) Traditional Ecological Knowledge (TEK) support team, Meriam Custodians have developed Meriam Areriba Tonar, a seasonal calendar that highlights how Meriam traditionally coexisted with their land and sea Country on Mer and surrounding islands, coral reefs and sand cay (Figures 36 and 37).

Figure 36 Mrs Lisa Lui and Mrs Vera Havili unveil the Meriam Areriba Tonar seasonal calendar poster

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Figure 36 Mrs Lisa Lui and Mrs Vera Havili unveil the Meriam Areriba Tonar seasonal calendar poster

Figure 37 Mer community representatives with Torres Strait Regional Authority Chairperson Mr Napau Pedro Stephen to celebrate the launch of the Meriba Areriba Tonar seasonal calendar

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Figure 37 Mer community representatives with Torres Strait Regional Authority Chairperson Mr Napau Pedro Stephen to celebrate the launch of the Meriba Areriba Tonar seasonal calendar

The seasonal calendars are giving a new generation of young people a renewed sense of understanding the interaction with and strength in Country and in our cultural connections with our local environment. They are a good way of communicating our knowledge and culture outside our Traditional Owner groups. The calendars are developed alongside our TEK databases to keep knowledge strong. The TSRA established a TEK Project in 2011 in response to the concerns raised by many Torres Strait Islander communities around the gradual loss of their Indigenous cultural knowledge – including stories, cultural practices and knowledge about their land, sea, plants, animals, the 4 winds and constellations. The TEK Project involved the development of a secure database for each community to record, store, protect and, where applicable, share traditional knowledge within their own community while adhering to their respective community’s cultural protocols.

Looking forward, we see good ways to document and share our knowledge and keep it strong for the future. Across Zenadth Kes, the support of the TEK databases is bringing traditional knowledge more strongly into management. This is important because instead of aligning environmental work to government timeframes and rhythms, it is important to run our programs by our seasonal calendars. Our Meriam Areriba Tonar is unique to our surrounding environments and what is unravelling around us in our part of the world. This uniqueness needs protecting and preserving, with attention to our cultural protocols, and to be respected by reciprocal sharing of knowledge. By taking the time to respect the uniqueness of each TEK seasonal calendar, we hope managers and researchers understand and come to learn our way of life in the turning of the seasons, and the importance of merging this knowledge into future planning activities.

By coming together and working as a team, Elders and youth from the 8 tribes, including our neighbouring island Dauareb tribe, have demonstrated the Meriam community’s commitment to protecting and preserving our language and cultural knowledge for future generations of Meriam Le. The Meriam Areriba Tonar poster is an important tool to rekindle our kids’ interest in our culture. Areriba Tonar depicts important elements of our ancestors’ traditional knowledge including the predominant seasonal winds and how Meriam people navigated, hunted, gardened and lived alongside nature in our part of the world. (Mr Falen D Passi)

Mr Passi was instrumental in developing the calendar and acknowledged the enormous contribution made to the project by the Meriam community and TSRA Rangers.

Healthy and resilient ocean ecosystems support the growth and development of ocean-based industries, which are among the fastest growing sectors globally and within Australia (AIMS 2018). Achieving a sustainable ocean economy is complex, requiring a balance of social, economic and environmental considerations, which are often interlinked, where one action may be detrimental to others or have unforeseen consequences (Ruijs et al. 2019). Effective and well-informed decision-making and support across Australian society requires integrated and robust evidence (NMSC 2015).

National accounting, a comprehensive and standardised system that measures the national economy, is a source of economic information for decision-makers. The United Nations System of Environmental–Economic Accounting (SEEA) extends national accounting to record a new class of assets, called natural capital (Dasgupta 2021). The services and benefits these assets provide and the pressures that may threaten their supply into the future are recorded using the SEEA extension (Vardon et al. 2018). Ocean accounting – the application of the SEEA principles in coastal and marine environments – provides an integrated information set for ocean management (Fenichel et al. 2020).

As part of Australia’s commitment to develop concepts and methodologies for ocean accounting, and to further understand the management and importance of marine protected areas, the IDEEA (Institute for Development of Environmental–Economic Accounting) Group was commissioned to produce a set of accounts for Geographe Marine Park in Western Australia (IDEEA Group 2020).

Marine parks are part of the Australian Government’s ocean management approach, conserving the environment and providing opportunities for recreational activities. Ocean accounting standards and methods were applied to compile information on ecosystems, commercial and recreational fisheries, marine recreational activities, carbon sequestration and storage, and vessel transportation and parking.

The Geographe Marine Park case study enabled the quantification of the contributions oceans make to society and the economy.

• In 2018, recreational fishers took more than 12,000 fishing trips, valued at over $2.2 million (consumer surplus).
• In 2019, ecosystems contributed approximately $316,000 to the local economy through whale-watching tourism ($254,000) and commercial fishing ($62,000).
• Seagrass meadows store approximately 6.2 million tonnes of carbon in soil, and each year sequester a further 27,569 tonnes (net) based on seagrass extent in 2014 (Figure 39).

Combining information through an accounting framework provides a greater understanding of the multiple benefits provided by the ecosystems within Geographe Marine Park, and further identifies the knowledge gaps and future monitoring required. Investments can be made in the accounting system, including the data underpinning it, to better address specific applications such as monitoring and evaluation for adaptive management.

Figure 39 Ocean accounting framework and estimates for seagrass in Geographe Marine Park

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Figure 39 Ocean accounting framework and estimates for seagrass in Geographe Marine Park

Source: IDEEA Group (2020)

Outlook and future directions

Australian state, territory and federal governments have committed to developing environmental-economic accounts. Australia is a leader in ocean accounting, with ongoing pilot studies testing concepts and methodologies in support of national ocean accounting.

National ocean accounting will enhance our understanding of the state of the ocean environment and will prove valuable for integrated, evidence-based ocean policy and further allow the assessment of whether policies are achieving their desired outcomes (Vardon et al. 2018).

Beyond governance, ocean accounts provide a deeper understanding of the environment, with data gathered for multiple uses at both local and national scales. Many concepts and methods are still to be developed and refined, with research and testing performed by a growing international community of practice, supported by the Global Ocean Accounts Partnership.