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In this paper, we adopt a multistakeholder governance perspective to study how people collectively respond to a grand challenge. Specifically, we show how working through governance obstacles—that is, coordinating and collaborating challenges arising from a multistakeholder governance approach to responding to grand challenges—can erode actors' ability to mitigate these wicked problems. We illustrate this process through an in-depth case study of WaterHealthOrg, a multistakeholder initiative established to address degrading water health in Australia's critical Great Barrier Reef region. Our findings reveal how, in an effort to avoid group paralysis or dissolution, actors employ specific practices to address governance obstacles. By doing so, actors set off a cumulative self-reinforcing process, driving them to consolidate rather than critically reflect on and adapt their collective response. Drawing on these insights, we develop a conceptual process model of how efforts to manage multistakeholder governance obstacles can generate governance traps that shape participants' ability to collectively respond and, ultimately, mitigate grand challenges. [ABSTRACT FROM AUTHOR]

Understanding and preserving the deep sea ecosystems is paramount for marine conservation efforts. Automated object (deep-sea biota) classification can enable the creation of detailed habitat maps that not only aid in biodiversity assessments but also provide essential data to evaluate ecosystem health and resilience. Having a significant source of labelled data helps prevent overfitting and enables training deep learning models with numerous parameters. In this paper, we contribute to the establishment of a significant deep-sea remotely operated vehicle (ROV) image classification dataset with 3994 images featuring deep-sea biota belonging to 33 classes. We manually label the images through rigorous quality control with human-in-the-loop image labelling. Leveraging data from ROV equipped with advanced imaging systems, our study provides results using novel deep-learning models for image classification. We use deep learning models including ResNet, DenseNet, Inception, and Inception-ResNet to benchmark the dataset that features class imbalance with many classes. Our results show that the Inception-ResNet model provides a mean classification accuracy of 65%, with AUC scores exceeding 0.8 for each class. [ABSTRACT FROM AUTHOR]

Summary: Crowdsourcing methods facilitate the production of scientific information by non‐experts. This form of citizen science (CS) is becoming a key source of complementary data in many fields to inform data‐driven decisions and study challenging problems. However, concerns about the validity of these data often constrain their utility. In this paper, we focus on the use of citizen science data in addressing complex challenges in environmental conservation. We consider this issue from three perspectives. First, we present a literature scan of papers that have employed Bayesian models with citizen science in ecology. Second, we compare several popular majority vote algorithms and introduce a Bayesian item response model that estimates and accounts for participants' abilities after adjusting for the difficulty of the images they have classified. The model also enables participants to be clustered into groups based on ability. Third, we apply the model in a case study involving the classification of corals from underwater images from the Great Barrier Reef, Australia. We show that the model achieved superior results in general and, for difficult tasks, a weighted consensus method that uses only groups of experts and experienced participants produced better performance measures. Moreover, we found that participants learn as they have more classification opportunities, which substantially increases their abilities over time. Overall, the paper demonstrates the feasibility of CS for answering complex and challenging ecological questions when these data are appropriately analysed. This serves as motivation for future work to increase the efficacy and trustworthiness of this emerging source of data. [ABSTRACT FROM AUTHOR]

Corals are sessile invertebrates living underwater in colorful structures known as reefs. Unfortunately, coral's temperature sensitivity is causing color bleaching, which hosts organisms that are crucial and consequently affect marine pharmacognosy. To address this problem, many researchers are developing cures and treatment procedures to restore bleached corals. However, before the cure, the researchers need to precisely localize the bleached corals in the Great Barrier Reef. The researchers have developed various visual classification frameworks to localize bleached corals. However, the performance of those techniques degrades with variations in illumination, orientation, scale, and view angle. In this paper, we develop highly noise-robust and invariant robust localization using bag-of-hybrid visual features (RL-BoHVF) for bleached corals by employing the AlexNet DNN and ColorTexture handcrafted by raw features. It is observed that the overall dimension is reduced by using the bag-of-feature method while achieving a classification accuracy of 96.20% on the balanced dataset collected from the Great Barrier Reef of Australia. Furthermore, the localization performance of the proposed model was evaluated on 342 images, which include both train and test segments. The model achieved superior performance compared to other standalone and hybrid DNN and handcrafted models reported in the literature. [ABSTRACT FROM AUTHOR]

Environmental damage has been of much concern, particularly in coastal areas and the oceans, given climate change and the drastic effects of pollution and extreme climate events. Our present-day analytical capabilities, along with advancements in information acquisition techniques such as remote sensing, can be utilised for the management and study of coral reef ecosystems. In this paper, we present Reef-Insight, an unsupervised machine learning framework that features advanced clustering methods and remote sensing for reef habitat mapping. Our framework compares different clustering methods for reef habitat mapping using remote sensing data. We evaluate four major clustering approaches based on qualitative and visual assessments which include k-means, hierarchical clustering, Gaussian mixture model, and density-based clustering. We utilise remote sensing data featuring the One Tree Island reef in Australia's Southern Great Barrier Reef. Our results indicate that clustering methods using remote sensing data can well identify benthic and geomorphic clusters in reefs when compared with other studies. Our results indicate that Reef-Insight can generate detailed reef habitat maps outlining distinct reef habitats and has the potential to enable further insights for reef restoration projects. [ABSTRACT FROM AUTHOR]

The use of ocean colour classification algorithms, linked to water quality gradients, can be a useful tool for mapping river plumes in both tropical and temperate systems. This approach has been applied in operational water quality programs in the Great Barrier Reef to map river plumes and assess trends in marine water composition and ecosystem health during flood periods. In this study, we used the Forel–Ule colour classification algorithm for Sentinel-3 OLCI imagery in an automated process to map monthly, annual and long-term plume movement in the temperate coastal system of Liverpool Bay (UK). We compared monthly river plume extent to the river flow and in situ water quality data between 2017–2020. The results showed a strong positive correlation (Spearman's rho = 0.68) between the river plume extent and the river flow and a strong link between the FUI defined waterbodies and nutrients, SPM, turbidity and salinity, hence the potential of the Forel–Ule index to act as a proxy for water quality in the temperate Liverpool Bay water. The paper discusses how the Forel–Ule index could be used in operational water quality programs to better understand river plumes and the land-based inputs to the coastal zones in UK waters, drawing parallels with methods that have been developed in the GBR and Citclops project. Overall, this paper provides the first insight into the systematic long-term river plume mapping in UK coastal waters using a fast, cost-effective, and reproducible workflow. The study created a novel water assessment typology based on the common physical, chemical and biological ocean colour properties captured in the Forel–Ule index, which could replace the more traditional eutrophication assessment regions centred around strict geographic and political boundaries. Additionally, the Forel–Ule assessment typology is particularly important since it identifies areas of the greatest impact from the land-based loads into the marine environment, and thus potential risks to vulnerable ecosystems. [ABSTRACT FROM AUTHOR]

In this paper we examine and critique adaptive management (AM) practices for protected areas (PAs), in pursuit of practices that can account for more-than-human relations. Engaging with empirical research from Australian PAs, we reflect on the formation of PAs as "exceptional places" where Nature is implicitly/explicitly to be controlled. We find that AM practices harness the spatial and temporal characteristics of the PAs to deliberatively construct a static and timeless scene, creating a particular vision of Nature. This metaphoric vision is captured "like a postcard." It reinforces and justifies static protectionism as Nature conservation, arraigning a series of material objects that are meant to assist with maintaining that image: that "reality." Using sentipensar as an exemplar, we explore and highlight relational and everchanging human-nonhuman engagements to contest the ontological dimensions of a static Nature and ideas of control and power associated with the binaries of Nature and culture. [ABSTRACT FROM AUTHOR]

The recent widespread and recurrent coral bleaching events over the Great Barrier Reef, the largest coral reef system on Earth and a hotspot of marine biodiversity, are a reminder of the vulnerability of reef ecosystems to human activities and a warming world. Protection of the Great Barrier Reef and similar reef ecosystems across Oceania requires a better understanding of environmental and socio-economic pressures, as well as the development of integrated management strategies. The rapid expansion of Earth Observation technologies and data has greatly advanced our capability to map and monitor reef habitats, ecological processing and exposure risk, providing spatially rich data essential to support and evaluate management and conservation strategies. However, these technologies are proportionally still under-utilized, and it is important to synthesise remote-sensing-derived tools and methods currently available for mapping reef ecosystems in Oceania to facilitate their intake in coral reefs studies. Publications in this Special Issue contribute toward filling this gap and explore recent advances in remote sensing of the Great Barrier Reef and other reef ecosystems in Oceania, from novel methodological approaches (sensors, algorithm development and improved thematic classification) to applications for environmental monitoring and management. [ABSTRACT FROM AUTHOR]

Achieving coastal and shallow-water bathymetry is essential for understanding the marine environment and for coastal management. Bathymetric data in shallow sea areas can currently be obtained using SDB (satellite-derived bathymetry) with multispectral satellites based on depth inversion models. In situ bathymetric data are crucial for validating empirical models but are currently limited in remote and unapproachable areas. In this paper, instead of using the measured water depth data, ICESat-2 (Ice, Cloud, and Land Elevation Satellite-2) ATL03 bathymetric points at different acquisition dates and multispectral imagery from Sentinel-2/GeoEye-1 were used to train and evaluate water depth inversion empirical models in two study regions: Shanhu Island in the South China Sea, and Heron Island in the Great Barrier Reef (GBR) in Australia. However, different sediment types also influenced the SDB results. Therefore, three types of sediments (sand, reef, and coral/algae) were analyzed for Heron Island, and four types of sediments (sand, reef, rubble and coral/algae) were analyzed for Shanhu Island. The results show that accuracy generally improved when sediment classification information was considered in both study areas. For Heron Island, the sand sediments showed the best performance in both models compared to the other sediments, with mean R2 and RMSE values of 0.90 and 1.52 m, respectively, representing a 5.6% improvement of the latter metric. For Shanhu Island, the rubble sediments showed the best accuracy in both models, and the average R2 and RMSE values were 0.97 and 0.65 m, respectively, indicating an RMSE improvement of 15.5%. Finally, bathymetric maps were generated in two regions based on the sediment classification results. [ABSTRACT FROM AUTHOR]

Herbicides used for weed management on agricultural land in Australia's Great Barrier Reef catchments are a key concern for its ecosystem, including the lagoon's marine plants and corals, whose productivity has been found to decline. The most reliable way to assess herbicide risk is by monitoring a site regularly, but this is costly and time-consuming, so numerical simulations and computer models are an alternative method. Despite the availability of low-cost and less labor-intensive modelling methods, they have been limited in their effectiveness due to a lack of specific herbicide usage data and an inadequate understanding of the breakdown and transport processes of herbicides after application. This paper reviews current findings regarding herbicide risk in all Great Barrier Reef catchments according to their agricultural land use, and the most recent Reef Water Quality Protection Plan recommendations. The various pathways for fate and transport of the herbicides were also examined, and a list of critical parameters was developed to help with computer simulations. The accuracy and reliability of modelling can be improved by including aerial drifts, interceptions by crop residues, mechanisms within the root zone, and subsurface and groundwater contributions to the herbicide load in the GBR lagoon. Moreover, the findings will provide new directions for management practices adoption data with the fate and transport model from paddock to reef and improve the reliability of model results. [ABSTRACT FROM AUTHOR]

The Great Barrier Reef Expedition (1928–1929) observed two of the earliest known examples of coral bleaching during a 13-month stay on Low Isles, northern Great Barrier Reef, Australia. The first was during austral summer in February 1929 in a shallow moat and the second during austral winter in June 1929 on a deeper seaward slope. Using Expedition records and modern analytical techniques, we geolocated previously undocumented photographs of bleaching and built a detailed picture of environmental conditions which show that the two episodes were driven by different proximate causes. The February bleaching coincided with highest annual seawater temperatures and Degree Heating Weeks, coupled with early afternoon aerial exposure leading to intense heating in tide pools and corals subjected to high solar insolation. Zooxanthellae densities would also have been at a seasonal low and the corals particularly susceptible to bleaching stress. In contrast in June, the seaward slope, normally submerged during the daytime, was aerially exposed to the afternoon sun and although seawater temperatures were 5 °C cooler than in the summer and despite relatively low sun altitudes and insolation in the winter, bleaching and mortality due to solar radiation was clearly visible on faces of exposed corals oriented towards the sun. Whilst reports of widespread temperature driven coral bleaching are commonplace today in an era of global warming, this paper demonstrates how similar environmental cues were involved a century ago and highlights the additional complexity of coral survival in the intertidal zone. [ABSTRACT FROM AUTHOR]

This paper explores how the imagined landscapes that act as a catalyst for World Heritage listing, are unable to be reconciled with formal heritage assessments. We explore this tension through two Australian World Heritage landscapes: the Great Barrier Reef and the Tasmanian Wilderness. The history of these listings suggests a teleological process driven by a desire to create authentic utopias. While utopias are imagined spaces, Paradise at the Reef and the Tasmanian Wilderness are realised through hyperreal landscapes (fakes). However, these wholistic landscapes dissolve into a series of inventories of species and numbers in official listing. We suggest the failure to recognise the hyperreal is a form of false consciousness that creates a tension between managing for formally recognised values and managing the unmanageable utopia, and that a broader use of cultural landscapes might be useful in addressing this divide. [ABSTRACT FROM AUTHOR]

Coral reefs provide important ecosystem services as well as economic and cultural benefits to society. Yet they are under significant threat from anthropogenic and natural threats, including climate change. Australia's Great Barrier Reef (GBR) is one such reef undergoing significant change. More radical interventions that go beyond traditional forms of management are being considered to help repair and restore the GBR. These are based on science and technologies that have yet to be widely tested. This paper reports on a study that seeks to identify and understand support for such interventions, and to understand the antecedents that explain support. The Norm Activation Model (NAM) was extended with a sample of 468 domestic and international tourists to Cairns, Australia. Personal norms had the largest direct influence on support for interventions, followed by attitudes. Awareness of consequences had a large positive impact on personal norms and a smaller positive impact on attitudes. A negative relationship was found between information and attitudes. Personal norms and attitudes also acted as mediators between awareness of consequences, information and support. No differences were found between domestic and international tourists. The results are discussed and theoretical and practical implications outlined. [ABSTRACT FROM AUTHOR]

This timely collation of case studies, written by and with Traditional Owners of diverse Australian offshore islands, offers direct insights into benefits arising from strategic and participatory action planning for biocultural island conservation and monitoring. We pay respect to the Old People and Elders whose dedicated care of their island homelands means we today can still experience their cultural and natural diversity. We extend greetings to our Pacifika neighbours, and to carers of islands around Earth. Our paper scopes socio-economic benefits arising from planning for islands, for Aboriginal peoples and Torres Strait Islanders, and more generally. Global, national, state and local co-investments support place-specific planning for some islands by Traditional Owners as a starting point toward shared governance and caring for Country. Case studies describe Country planning for Mayala Country in Australia's northwest, Woppaburra experiences within the Great Barrier Reef World Heritage Area and integrated biocultural health monitoring arising from remote island Indigenous Protected Area planning in Torres Strait. New institutional initiatives are also seeking to create solid foundations for more substantive island research collaborations. Across Australia, novel relationships grounded in culturally assured, holistically integrated approaches to island governance and caring for Country involving Traditional Owners and island resource users/managers are creating equity in livelihoods and stronger wellbeing. Australia's innovative Sea Country collaborations, with priorities initiated and led by island Traditional Owners, carry real value for sustained island conservation and provide positive inspirations for global humanity in the accelerating Anthropocene. Earth's islands face grave challenges. In Australia, innovation in island knowledge sharing between Traditional Owners and other island users and managers is moving beyond the participatory action planning space to generate equity in livelihoods and wellbeing on Sea Country. The tangible benefits arising are grounded in cultural governance and authority. [ABSTRACT FROM AUTHOR]

Identifying mechanisms that drive population divergence under varying geographic and ecological scenarios can inform our understanding of evolution and speciation. In particular, analysis of genetic data from island populations with known colonisation timelines allows us to identify potential source populations of diverging island subspecies and current relationships among populations. Silvereyes (Zosterops lateralis) are a small passerine that have served as a valuable study system to investigate evolutionary patterns on both large and small geographic scales. We examined genetic relatedness and diversity of two silvereye subspecies, the mainland Z. l. cornwalli and island Z. l. chlorocephalus, and used 18 077 single nucleotide polymorphisms (SNPs), to compare locations across southeast Queensland, Australia. Although silvereyes are prolific island colonisers our findings revealed population divergence over relatively small spatial scales was strongly influenced by geographic isolation mediated by water barriers. Strong genetic connectivity was displayed between mainland sites, but minimal inter-island connectivity was shown despite comparable sampling distances. Genetic diversity analysis showed little difference in heterozygosity between island and mainland populations, but lower inbreeding scores among the island populations. Our study confirmed the range of the Z. l. chlorocephalus subspecies throughout the southern Great Barrier Reef. Our results show that water barriers and not geographic distance per se are important in driving incipient divergence in island populations. This helps to explain the relatively high number of phenotypically differentiated, but often geographically proximate, island silvereye subspecies compared to a lower number of phenotypically less well-defined Australian continental subspecies. [ABSTRACT FROM AUTHOR]

Local meteorology over the Great Barrier Reef (GBR) can significantly influence ocean temperatures, which in turn impacts coral ecosystems. While El Niño–Southern Oscillation (ENSO) provides insight into the expected synoptic states, it lacks details of anticipated sub‐seasonal weather variability at local scales. This study explores the influence of the Madden‐Julian oscillation (MJO) on Australian tropical climate, both independently and in combination with ENSO, focusing on GBR impacts. We find that during El Niño periods, including the summer of 2009/10, faster propagating MJO patterns can disrupt background warm, dry conditions, and potentially provide cooling relief via increased cloud cover and stronger winds. In La Niña periods, such as the summer of 2021/22, the MJO tends to be prevented from passing the Maritime continent, forcing it to remain in a standing pattern in the Indian Ocean. This leads to decreased cloud cover and weaker winds over the GBR, generating warm ocean anomalies. Plain Language Summary: Bleaching is likely when tropical corals are exposed to ocean temperatures above a threshold for a prolonged period. In austral summer, tropical weather over the Great Barrier Reef (GBR) can vary from hot and sunny to stormy with rain and strong winds. During El Niño, summer weather over the GBR is typically warm, still, and dry, increasing the likelihood of coral bleaching due to increased exposure to solar radiation and decreased mixing. During La Niña, tropical storms, with cooling effects through increased rainfall and cloud cover, are more typical. The Madden‐Julian oscillation (MJO) is an eastward moving storm pattern near the equator that can also influence the background climate over the GBR. We find that the MJO can significantly influence the weather variability over the GBR, altering the expected states of El Niño and La Niña periods. Key Points: Composite maps show how the Madden‐Julian oscillation (MJO) can change meteorological patterns on the Great Barrier ReefCluster analysis is used to show the types of MJO propagation patterns likely to occur during El Niño and La Niña periodsOcean temperature variability is discussed with El Niño/La Niña phases as the background states and the MJO as a sub‐seasonal modulator [ABSTRACT FROM AUTHOR]

Suspended sediment is a significant threat to the Great Barrier Reef (GBR) ecosystem. This catchment pollutant stems primarily from terrestrial soil erosion. Bulk masses of sediments have potential to propagate from river plumes into the mid-shelf and outer-shelf regions. Existing sediment forecasting methods suffer from the problem of low-resolution predictions, making them unsuitable for wide area coverage. In this paper, a novel sediment distribution prediction model is proposed to augment existing water quality management programs for the GBR. This model is based on the state-of-the-art Transformer network in conjunction with the well-known finite element analysis. For model training, the emerging physics-informed neural network is employed to incorporate both simulated and measured sediment data. Our proposed Finite Element Transformer (FE-Transformer) model offers accurate predictions of sediment across the entire GBR. It provides unblurred outputs, which cannot be achieved with previous next-frame prediction models. This paves a way for accurate forecasting of sediment, which in turn may lead to improved water quality management for the GBR. • Vision Transformer is proposed for next-frame prediction. • Finite element analysis is integrated with the Vision Transformer. • Sediment distribution in the GBR is forecasted using the proposed FE-Transformer. • PINN is employed to merge sediment PDE solutions with in-situ measured data. • The proposed model produces highly accurate unblurred output frames. [ABSTRACT FROM AUTHOR]

An obituary for the Great Barrier Reef (the Reef) by travel and food writer Rowan Jacobsen (2016) commemorated its 'lifetime accomplishments' in Outside, the US outdoor recreational magazine. 'News' of the Reef's demise went viral and the economic and political furore that followed was immense. Tourism industries, especially reliant on international arrivals, were impacted as potential visitors accepted the Reef's passing as fact. Politicians scampered to reassure Australians and the globe that the Reef was indeed still alive and beautiful. In the Australian public sphere, climate science deniers, alongside those advocating for climate action, collided over the impacts of global warming to Reef health. Subsequent mass coral bleaching events in 2016, 2017 and 2020 sustained at the very least, the idea that the Reef was, or was soon to be, dead. Our paper follows the idea of a 'dead Reef' in the context of historical and recent debates about Reef protection. Using Google Trends, we identify Jacobsen's article as the source of increased Australian and global ideation of a 'dead Reef'. As a site of local and global environmental communication – where human relations to nature are expressed and understood - the Reef holds extraordinary story telling power. At the current junction then, the way we communicate the Reef is critical to public understanding and political action on climate change. We conclude Jacobsen's article is an example of the problems of satirical communication, serving to amplify existing conflicts and undermine efforts to foster to climate action. [ABSTRACT FROM AUTHOR]

• River plumes are a source of pollutants in the Great Barrier Reef, Australia. • Plume dispersion is simulated using a coupled Lagrangian-Eulerian-ocean model. • Lagrangian particle density is computed from application of Voronoi diagrams. • Lagrangian particle densities and Eulerian tracer concentrations are comparable. • Lagrangian model is validated using satellite imagery and satellite Chlorophyll-a. In this paper, we describe methods to verify the adequacy and accuracy of Lagrangian particles from a Lagrangian model to reproduce the concentrations of a passive tracer from an Eulerian-model in river plumes. The modelling simulates plumes from two major rivers discharging in the Great Barrier Reef (GBR), Australia, under real-world scenarios. The study has been a part of a major project to aid in the protection of the GBR system from the impacts of extreme events and climate change. We employ the Regional Ocean Modelling System (ROMS) activated with its built-in Lagrangian model, and forced with wind fields from global models and recorded river volume discharges. The ROMS-Lagrangian model tracks the Lagrangian particles using the spatially interpolated velocities computed on the Eulerian ROMS three-dimensional (3D) grid. The Lagrangian particles are released in the river in proportion to the measured river volume flux. We apply a novel technique that exploits Voronoi polygon areas to convert Lagrangian particle separation into a concentration field. This facilitates comparison with the passive tracer concentrations driven by the Eulerian velocities computed on the ROMS 3D grid. We evaluate the fate of Lagrangian particles activated on a 4-km grid resolution with those of equivalent Eulerian tracer concentrations. For validation, we compare the Lagrangian particles with the Eulerian passive tracer simulated using a higher model grid resolution of 500-m, and found that the computed Lagrangian particle concentrations showed similar overall patterns compared to the passive tracer concentrations from both the coarse 4-km, and high-resolution 500-m Eulerian models. The spatial extent of the particles was in better agreement with the coarse 4-km model than with the higher resolution 500-m model. The clustering of particles resulted in structures at finer scales than the Eulerian model, over the high particle density areas that compared well against observations. The Lagrangian particles are able to capture the general river plume patterns seen in the satellite MODIS images and the satellite derived Chlorophyll-a. We further compare the online ROMS model with an offline particle tracker, OceanPARCELS and determined the similarity of results from both online and offline methods. Overall, our study demonstrates the viability to use Lagrangian particles to reproduce the Eulerian tracer properties, which can be combined with particle properties include tracer age providing to enhance the guidance on the distribution and concentration of effluent from localised flooding river events. [ABSTRACT FROM AUTHOR]

The Great Barrier Reef lagoon is a large, relatively shallow area of the Australian continental shelf, isolated from the open ocean by a dense matrix of coral reefs. As the lagoon is generally vertically well mixed by strong tidal currents and wind, it is perhaps not surprising there is no mention in the open literature of the occurrence of internal waves there. Nevertheless, high-resolution satellite imagery is shown in this article to reveal the characteristic surface expressions of nonlinear internal waves in the lagoon. The waves are confined to periods of low winds in austral spring and summer, making them a potentially important mechanism for the dispersal of algae and planktonic larvae. The imagery suggests a link between the waves and tidally forced submesoscale jets and vortices, but the actual mechanism generating the internal waves is unclear and requires investigation. [ABSTRACT FROM AUTHOR]

Animals are influenced by the season, yet we know little about the changes that occur in most species throughout the year. This is particularly true in tropical marine animals that experience relatively small annual temperature and daylight changes. Like many coral reef inhabitants, the crown-of-thorns starfish (COTS), well known as a notorious consumer of corals and destroyer of coral reefs, reproduces exclusively in the summer. By comparing gene expression in 7 somatic tissues procured from wild COTS sampled on the Great Barrier Reef, we identified more than 2,000 protein-coding genes that change significantly between summer and winter. COTS genes that appear to mediate conspecific communication, including both signalling factors released into the surrounding sea water and cell surface receptors, are up-regulated in external secretory and sensory tissues in the summer, often in a sex-specific manner. Sexually dimorphic gene expression appears to be underpinned by sex- and season-specific transcription factors (TFs) and gene regulatory programs. There are over 100 TFs that are seasonally expressed, 87% of which are significantly up-regulated in the summer. Six nuclear receptors are up-regulated in all tissues in the summer, suggesting that systemic seasonal changes are hormonally controlled, as in vertebrates. Unexpectedly, there is a suite of stress-related chaperone proteins and TFs, including HIFa, ATF3, C/EBP, CREB, and NF-κB, that are uniquely and widely co-expressed in gravid females. The up-regulation of these stress proteins in the summer suggests the demands of oogenesis in this highly fecund starfish affects protein stability and turnover in somatic cells. Together, these circannual changes in gene expression provide novel insights into seasonal changes in this coral reef pest and have the potential to identify vulnerabilities for targeted biocontrol. The crown-of-thorns starfish (COTS), a notorious consumer of corals and destroyer of coral reefs, reproduces exclusively in the summer. This study reveals seasonal changes in COTS gene expression, providing molecular leads for novel biocontrol methods by revealing new insights into circannual biological rhythms in tropical oceans. [ABSTRACT FROM AUTHOR]

Trade wind clouds are ubiquitous across the subtropical oceans, including the Great Barrier Reef (GBR), playing an important role in modulating the regional energy budget. These shallow clouds, however, are by their nature sensitive to perturbations in both their thermodynamic environment and microphysical background. In this study, we employ the Weather Research and Forecasting (WRF) model with a convection-permitting configuration at 1 km resolution to examine the sensitivity of the trade wind clouds to different local forcings over the GBR. A range of local forcings including coastal topography, sea surface temperature (SST), and local aerosol loading is examined. This study shows a strong response of cloud fraction and accumulated precipitation to orographic forcing both over the mountains and upwind over the GBR. Orographic lifting, low-level convergence, and lower troposphere stability are found to be crucial in explaining the cloud and precipitation features over the coastal mountains downwind of the GBR. However, clouds over the upwind ocean are more strongly constrained by the trade wind inversion, whose properties are, in part, regulated by the coastal topography. On the scales considered in this study, the warm-cloud fraction and the ensuant precipitation over the GBR show only a small response to the local SST forcing, with this response being tied to the surface flux and lower troposphere stability. Cloud microphysical properties, including cloud droplet number concentration, liquid water path, and precipitation, are sensitive to the changes in atmospheric aerosol population over the GBR. While cloud fraction shows little responses, a slight deepening of the simulated clouds is evident over the upwind region in correspondence to the increased aerosol number concentration. A downwind effect of aerosol loading on simulated cloud and precipitation properties is further noted. [ABSTRACT FROM AUTHOR]

Climate change projections for coral reefs are founded exclusively on sea surface temperatures (SST). While SST projections are relevant for the shallowest reefs, neglecting ocean stratification overlooks the striking differences in temperature experienced by deeper reefs for all or part of the year. Density stratification creates a buoyancy barrier partitioning the upper and lower parts of the water column. Here, we mechanistically downscale climate models and quantify patterns of thermal stratification above mesophotic corals (depth 30 to 50 m) of the Great Barrier Reef (GBR). Stratification insulates many offshore regions of the GBR from heatwaves at the surface. However, this protection is lost once global average temperatures exceed ~3 ℃ above preindustrial, after which mesophotic temperatures surpass a recognized threshold of 30 ℃ for coral mortality. Bottom temperatures on the GBR (30 to 50 m) from 2050 to 2060 are estimated to increase by ~0.5 to 1 ℃ under lower climate emissions (SSP1-1.9) and ~1.2 to 1.7 ℃ under higher climate emissions (SSP5-8.5). In short, mesophotic coral reefs are also threatened by climate change and research might prioritize the sensitivity of such corals to stress. [ABSTRACT FROM AUTHOR]

Microbial diversity has been extensively explored in reef-building corals. However, the functional roles of coral-associated microorganisms remain poorly elucidated. Here, we recover 191 bacterial and 10 archaeal metagenome-assembled genomes (MAGs) from the coral Acropora kenti (formerly A. tenuis) and adjacent seawater, to identify microbial functions and metabolic interactions within the holobiont. We show that 82 MAGs were specific to the A. kenti holobiont, including members of the Pseudomonadota, Bacteroidota, and Desulfobacterota. A. kenti-specific MAGs displayed significant differences in their genomic features and functional potential relative to seawater-specific MAGs, with a higher prevalence of genes involved in host immune system evasion, nitrogen and carbon fixation, and synthesis of five essential B-vitamins. We find a diversity of A. kenti-specific MAGs encode the biosynthesis of essential amino acids, such as tryptophan, histidine, and lysine, which cannot be de novo synthesised by the host or Symbiodiniaceae. Across a water quality gradient spanning 2° of latitude, A. kenti microbial community composition is correlated to increased temperature and dissolved inorganic nitrogen, with corresponding enrichment in molecular chaperones, nitrate reductases, and a heat-shock protein. We reveal mechanisms of A. kenti-microbiome-symbiosis on the Great Barrier Reef, highlighting the interactions underpinning the health of this keystone holobiont. This study provides insights into the functional roles of microbial symbionts within the reef-building coral Acropora kenti. The findings reveal molecular mechanisms underpinning coral health and adaptation to local environmental stressors, which may support host resilience in the face of anthropogenic climate change and pollution. [ABSTRACT FROM AUTHOR]

Quantifying ecological memory could be done at several levels from the rate of physiological changes in an ecosystem all the way down to responses at the genetic level. One way of unlocking the information encoded in a collective environmental memory is to examine the recorded time-series data generated by different components of an ecosystem. In this paper, we probe into the case of the Great Barrier Reef (GBR) which is threatened by elevated sea surface temperatures (SST) and ocean acidification attributed to rising atmospheric CO2 levels. Specifically, we investigate the interrelated dynamics between the degradation of the GBR, SST, and rising atmospheric CO2 levels, by considering three datasets: (a) the mean percentage hard coral cover of the GBR from the archives of the Australian Institute of Marine Science; (b) SST close to the GBR from the National Oceanic and Atmospheric Administration; and (c) the Keeling curve for atmospheric CO2 levels measured by the Mauna Loa Observatory. We show that fluctuating observables in these datasets have the same memory behavior described by a non-Markovian stochastic process. All three datasets show a good match between empirical and analytical mean square deviation. An explicit analytical form for the corresponding probability density function is obtained which obeys a modified diffusion equation with a time dependent diffusion coefficient. This study provides a new perspective on the similarities of and interaction between the GBR's declining hard coral cover, SST, and rising atmospheric CO2 levels by putting all three systems into one unified framework indexed by a memory parameter μ and a characteristic frequency ν . The short-time dynamics of CO2 levels and SST fall in the superdiffusive regime, while the GBR exhibits hyperballistic fluctuation in percent coral cover with the highest values for μ and ν . [ABSTRACT FROM AUTHOR]

Fishery stock assessments are often based on morphometric data from underwater diver surveys and landing surveys. Measurements of body length are usually converted to estimates of body weight, yet length–weight equations might differ among localities. We evaluated morphometric models for the sea cucumber, Pearsonothuria graeffei, collected at Lizard Island on the northern Great Barrier Reef, Australia, and explored differences in relative condition factor (Kn) across animal sizes. The estimation of body weight was compared among relationships with four different body size metrics: observed body length, SLW (square root of the body length–width product), recalculated body length (Le) from SLW, and body basal area. The basal area of the animals, the SLW index and Le provided more reliable estimations for body weight than using body length alone yet accounted for half of the variation in body weight. The length–weight relationship from animals at Lizard Island differed considerably from relationships published for the same species in New Caledonia and Philippines. Body condition was variable, and our model predicted a peak at 35 cm body length. Body metrics such as basal area, SLW index, and Le could offer more precise models for estimating the body weight of sea cucumbers for fishery purposes. Equations for estimating body weight from length and width of the sea cucumbers should be based on locality-specific data because morphometric relationships are spatially variable. [ABSTRACT FROM AUTHOR]

Gnathia antennacrassa sp. nov. from seagrass beds off Rottnest Island, Western Australia is the first record of any gnathiid from the entirety of Western Australia; the male can be distinguished from congeners by the stout peduncular articles of the antenna. Gnathia taurus sp. nov. is described from two adult specimens reared from praniza larvae found infecting elasmobranch fishes at Heron Island, southern Great Barrier Reef; the males can be distinguished from all congeners by the dorsally strongly elongate mandibles and smoothly rounded mediofrontal process on the anterior part of cephalosome. Gnathia aff. maculosa Ota & Hirose, 2009 is recorded from Australia, together with further records of G. trimaculata Coetzee, Smit, Grutter & Davies, 2009 and G. grandilaris Coetzee, Smit, Grutter & Davies, 2008, all from elasmobranch fishes. [ABSTRACT FROM AUTHOR]

The Great Barrier Reef has become one of the latest casualties of the climate crisis, suffering mass coral mortalities following three marine heat waves since 2016. Two new papers untangle the cumulative effects of these disturbances on the reef's resilience. [ABSTRACT FROM AUTHOR]

• i-RAT (https://i.rat-net) is an APSIM-based interactive web application for sugarcane growers. • Users can easily conduct 'what-if' analyses without needing to setup APSIM-Sugar. • It assesses the impacts of changed irrigation practices on revenue, productivity, water quality, carbon/nitrogen cycles, and greenhouse gas emissions. • i-RAT promotes sustainable technologies for enhanced irrigation practices. Water pollution and climate change are among the greatest threats to the iconic Great Barrier Reef (GBR). To improve the GBR's long-term outlook, making improvements on these fronts is required. Owing to the complex interactions between soils, climate, and farm management, a tool is needed to guide agricultural land managers about which management practice changes are more likely to deliver improved water quality and climate resilience outcomes whilst maintaining profitability. Using concepts drawn from social studies of science and technology, a 'discussion' support system (DSS) named I rrigation R apid A ssessment T ool (i-RAT) was developed through participatory processes designed to enhance co-learning from the development of this DSS. i-RAT is a rapid assessment-visualisation tool in an interactive web application (https://i-rat.net) to visualise the impacts of changed irrigation practices for sugarcane farmers and extension staff. Specifically, i-RAT compares these impacts regarding farm economics, water quality, productivity, carbon and nitrogen cycles, and greenhouse gas emission. The core of i-RAT is the sugarcane module from the Agricultural Production Systems sIMulator (APSIM) modelling platform. i-RAT was first developed for the Burdekin sugarcane growing region in Queensland (Australia's largest sugarcane producing region). Various soil types and management scenarios representing farming practices in the Burdekin region were used for simulations (1971–2021) to generate a datacube. In this paper, we describe how fundamental learnings about more (drought) resilient farming systems and more sustainable irrigation practices can be extracted from i-RAT. Details of the participatory approach with research and industry partners that informed the design and function of i-RAT and how APSIM was set up and parameterised are described. A 'what-if' analysis demonstrated the i-RAT features and application. [ABSTRACT FROM AUTHOR]

Long distance dispersal (LDD) contributes to the replenishment and recovery of tropical seagrass habitats exposed to disturbance, such as cyclones and infrastructure development. However, our current knowledge regarding the physical attributes of seagrass fragments that influence LDD predominantly stems from temperate species and regions. The goal of this paper is to measure seagrass fragment density and viability in two tropical species, assessing various factors influencing their distribution. We measured the density and viability of floating seagrass fragments for two tropical seagrass species (Zostera muelleri and Halodule uninervis) in two coastal seagrass meadows in the central Great Barrier Reef World Heritage Area, Australia. We assessed the effect of wind speed, wind direction, seagrass growing/senescent season, seagrass meadow density, meadow location and dugong foraging intensity on fragment density. We also measured seagrass fragment structure and fragment viability; i.e., potential to establish into a new plant. We found that seagrass meadow density, season, wind direction and wind speed influenced total fragment density, while season and wind speed influenced the density of viable fragments. Dugong foraging intensity did not influence fragment density. Our results indicate that wave action from winds combined with high seagrass meadow density increases seagrass fragment creation, and that more fragments are produced during the growing than the senescent season. Seagrass fragments classified as viable for Z. muelleri and H. uninervis had significantly more shoots and leaves than non-viable fragments. We collected 0.63 (±0.08 SE) floating viable fragments 100 m−2 in the growing season, and 0.13 (±0.03 SE) viable fragments 100 m−2 in the senescent season. Over a third (38%) of all fragments collected were viable. There is likely to be a large number of viable seagrass fragments available for long distance dispersal. This study's outputs can inform dispersal and connectivity models that are used to direct seagrass ecosystem management and conservation strategies. • There are large numbers of viable seagrass fragments available for dispersal. • Moderate winds with high seagrass density increases seagrass fragment creation. • More seagrass fragments are produced during the growing than the senescent season. • Seagrass fragments have more shoots and leaves than non-viable fragments. • Over a third (38%) of all floating fragments are viable. [ABSTRACT FROM AUTHOR]

Mangrove forests are the dominant vegetation growing on low wooded islands, which occur in the Caribbean, Indian and Pacific Oceans. In the northern Great Barrier Reef, we map remarkable, undocumented mangrove forest extension on 10 low wooded islands in the Howick Group that collectively equates to an area of 667 000 m2 (66.7 ha). We combine extensive field survey with canopy height models derived from RPA imagery and allometric scaling to quantify above ground biomass in both old (pre-1973) and new (post-1973) forest areas. Forest expansion added approximately 10 233 tonnes of new biomass since the early 1970s. We suggest that such substantial expansion of mangrove forest has occurred within a short time span in response to changing environmental controls. These may include sea-level rise, sediment transport and deposition, cyclone impact and the development of associated reef flat sedimentary landforms including unconsolidated and lithified shingle ridges, which influence reef flat hydrodynamics. Our observations highlight the globally dynamic response of mangrove distribution and forest structure to environmental change and provide timely new estimates from understudied reef island settings. [ABSTRACT FROM AUTHOR]

Long-term movements of adult marine animals predicate spatial management measures. Sea cucumbers are intensely exploited worldwide, yet few studies have assessed their long-term movement potential. Elephant trunkfish, Holothuria (Microthele) fuscopunctata, is a large coral reef holothuroid. At four sites at Lizard Island, northern Great Barrier Reef, we photographically marked and georeferenced 36 H. fuscopunctata, ranging 1.4–5.1 kg in weight. In broader searches one year later, we recaptured 92% of the animals. Their displacements were comparable among sites and averaged 8.7 m yr−1. None of the movements could be characterised as nomadic; the maximum displacement was 21 m. Contrary to expectations, smaller animals tended to roam further than larger animals (p = 0.025). Our study shows that certain large-bodied sea cucumbers might not displace far over annual timescales. This empirical evidence of home ranging reshapes our understanding of echinoderm mobility and reveals a behaviour that would exacerbate Allee effects at low population densities. [ABSTRACT FROM AUTHOR]

What gets measured gets managed is an axiom common to the business world that also applies to the management of environmental assets and processes. But what is the most adequate way to measure ecosystem value to optimise ecosystem management? In this paper, we unpack three valuation frameworks often applied in understanding ecosystem services and their benefits: 1) the Ecosystem Services framework, operationalised by the United Nations System of Environmental Economic Accounting - Ecosystem Accounting (SEEA-EA) framework; 2) value-centric approaches operationalised by the Total Economic Value framework; and 3) First Nations Peoples (FNP) frameworks, which seek to capture values from FNPs' perspective. By assessing the strengths and weaknesses of these value frameworks for managing the World's largest reef ecosystem—the Australian Great Barrier Reef—we construct an extended SEEA-EA valuation framework tailored to complex coastal settings. The significance of our approach is the inclusion of the whole range of benefits from all coastal and marine uses and users and therefore the integration of non-market and FNP values into the more traditional market-based valuation approach. Assessments that jointly consider multiple values originating from these three different frameworks are more likely to produce sustainable management outcomes than more restrictive approaches. [Display omitted] [ABSTRACT FROM AUTHOR]

River run-off has long been regarded as the largest source of organic-rich suspended particulate matter (SPM) in the Great Barrier Reef (GBR), contributing to high turbidity, pollutant exposure and increasing vulnerability of coral reef to climate change. However, the terrestrial versus marine origin of the SPM in the GBR is uncertain. Here we provide multiple lines of evidence (13C NMR, isotopic and genetic fingerprints) to unravel that a considerable proportion of the terrestrially-derived SPM is degraded in the riverine and estuarine mixing zones before it is transported further offshore. The fingerprints of SPM in the marine environment were completely different from those of terrestrial origin but more consistent with that formed by marine phytoplankton. This result indicates that the SPM in the GBR may not have terrestrial origin but produced locally in the marine environment, which has significant implications on developing better-targeted management practices for improving water quality in the GBR. This multidisciplinary fingerprinting study, using isotopic, structural and genetic fingerprints, has shown that the suspended particulate matter in the Great Barrier Reef does not have terrestrial origin but produced locally by marine phytoplankton [ABSTRACT FROM AUTHOR]

Denitrification is a key process in the global nitrogen (N) cycle, causing both nitrous oxide (N2O) and dinitrogen (N2) emissions. However, estimates of seasonal denitrification losses (N2O + N2) are scarce, reflecting methodological difficulties in measuring soil‐borne N2 emissions against the high atmospheric N2 background and challenges regarding their spatio‐temporal upscaling. This study investigated N2O + N2 losses in response to N fertilizer rates (0, 100, 150, 200, and 250 kg N ha−1) on two intensively managed tropical sugarcane farms in Australia, by combining automated N2O monitoring, in situ N2 and N2O measurements using the 15N gas flux method and fertilizer 15N recoveries at harvest. Dynamic changes in the N2O/(N2O + N2) ratio (<0.01 to 0.768) were explained by fitting generalized additive mixed models (GAMMs) with soil factors to upscale high temporal‐resolution N2O data to daily N2 emissions over the season. Cumulative N2O + N2 losses ranged from 12 to 87 kg N ha−1, increasing non‐linearly with increasing N fertilizer rates. Emissions of N2O + N2 accounted for 31%–78% of fertilizer 15N losses and were dominated by environmentally benign N2 emissions. The contribution of denitrification to N fertilizer loss decreased with increasing N rates, suggesting increasing significance of other N loss pathways including leaching and runoff at higher N rates. This study delivers a blueprint approach to extrapolate denitrification measurements at both temporal and spatial scales, which can be applied in fertilized agroecosystems. Robust estimates of denitrification losses determined using this method will help to improve cropping system modeling approaches, advancing our understanding of the N cycle across scales. Plain Language Summary: Denitrification is a soil nitrogen (N) transformation process, producing the potent greenhouse gas (GHG) nitrous oxide (N2O), while turning reactive N into environmentally benign dinitrogen (N2). The response of these N losses to N fertilizer inputs is critical to reduce environmental impacts while maintaining crop productivity in agriculture. However, difficulties in measuring soil‐borne N2 against atmospheric N2 and upscaling of these emissions to the farm scale hinder estimation of denitrification losses, leaving denitrification as a major uncertainty for N budgets. This study quantified denitrification losses in response to N fertilizer rates on sugarcane farms in Australia, by combining automated GHG monitoring systems, N isotope techniques and statistical models. This unique approach demonstrated denitrification as a major N loss pathway, increasing nonlinearly with increasing N rates. Fertilizer N budgets showed that environmentally harmful N losses increased more than proportionally with N inputs. These findings emphasize that excessive N fertilizer use leads to agronomic inefficiency with severe adverse effects on the surrounding ecosystems such as the Great Barrier Reef. The novel approach presented here will advance our understanding of N cycling across scales and thus aid in reducing the environmental footprint of global agricultural production. Key Points: A novel method to estimate N2O + N2 losses by combining high‐frequency N2O data, in situ 15N gas flux measurements and fertilizer 15N recoveriesDenitrification losses of 12–87 kg N ha−1 were dominated by N2 (>94%) and increased non‐linearly with increasing N ratesDenitrification accounted for 31%–78% of N fertilizer losses while the proportion of reactive N losses increased with increasing N rates [ABSTRACT FROM AUTHOR]

Following an incidental observation of captive Clibanarius corallinus (H. Milne Edwards, 1848) supposedly removing algae from each other's shells, we conducted a feeding experiment over 72 hours to understand its potential role as a mesograzer in coral reef ecosystems. Epiphyte-covered, coral rubble fragments of Acropora spp. were exposed to hermit crab (N = 41) activity for 72 h in a flow-through seawater aquarium system at Heron Island, southern Great Barrier Reef, Australia to understand whether hermit crabs could remove epilithic algae and if so, to what extent. Coral fragments exposed to the hermit crabs had 9.1% less chlorophyll at the end of the experiment. The detritus generated in the experimental set-up had 2.4 times more chlorophyll and 33.4% less organic biomass than the detritus generated in the control environment. The crabs did on average lose 0.11 g of their initial weight, which could have been a consequence of the experimental set-up. These results suggest that C. corallinus has the potential to contribute to the control of epilithic algae in coral reefs, with such effect having hitherto been overlooked as a result of the cryptic behaviour of this hermit crab species. [ABSTRACT FROM AUTHOR]

Coral reefs have become one of the most vulnerable ecosystems worldwide due to rising environmental and anthropogenic pressures. Methods from experimental design can be used to furnish our ability to monitor such ecosystems efficiently. Recently, adaptive design approaches have been proposed for monitoring coral reefs; however, questions have surfaced around the ability of such approaches to capture trends over time. The aim of this study was to develop an approach to assess trends in hard coral cover and evaluate the effectiveness of adaptive designs for estimating such trends in coral reef communities within a region of the Great Barrier Reef. Our approach was couched within a Bayesian design and inference framework such that uncertainty was captured rigorously and so that information from accumulating data can be incorporated straightforwardly to inform future data collection. The designs found under this approach were compared to historical non‐adaptive designs which surveyed all locations over time. Through this comparison, we show that adaptive designs can maintain trends over time with little to no loss in information, even when sampling effort is substantially reduced. Accordingly, this research serves to further promote adaptive design methods for efficiently and effectively sampling in ecological monitoring. [ABSTRACT FROM AUTHOR]

The Reef 2050 Water Quality Improvement Plan 2017–2022 identified that changes to evaluation practices were an urgent need if ambitious water quality targets were to be realised. To understand if progress had been made, this study synthesised publicly available evidence for ten projects aiming to engage sugarcane growers in practice change. The aims of this study were to identify factors facilitating or preventing practice change in sugarcane growing, drawing on monitoring and evaluation evidence that was publicly available for the ten projects. Twenty-one peer-reviewed articles and government and industry reports were collated and analysed. Thematic analysis identified seven enablers of engagement with practice changes resulting from project participation: government and industry partnerships, effective communication, training and education, grower or community leadership, financial support, return on investment and social factors. This review showed that a lack of enabling factors is a barrier to program adoption and practice change. Additional barriers were lack of availability of alternatives, lack of clear and transparent monitoring and evaluation for projects, lack of trust between stakeholders and competing stakeholder interests. [ABSTRACT FROM AUTHOR]

Climate change poses substantial risks to natural and human systems and effective response is essential. Underwater sculptures have been installed at multiple global locations to restore damaged reefs, increase tourism and educate visitors. There has been limited research that evaluates the environmental, social, cultural and economic costs of impacts such as cyclones and interventions such as underwater sculptures. Thisresearch investigated the social acceptance of underwater sculptures in Australia's Great Barrier Reef Marine Park. Following three months of planning and consultation, four sculptures were temporarily deployed at several habitats to facilitate action research on underwater sculptures and tourism. Respondents were supportive of installing sculptures in subtidal zones. The consultation and 'proof of concept' action research informed environmental assessment processes for installing permanent subtidal underwater sculptures. We report that tourist satisfaction of coral reefs damaged by a cyclone was low and following an intervention and installation of underwater sculptures satisfaction was high. [ABSTRACT FROM AUTHOR]

Copyright of Policy Studies Journal is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Universal Adaptive Strategy Theory aims to predict how taxa and assemblages respond to disturbances on the basis of adaptive strategy group (ASG) membership. Here, we test such predictions using the adaptive strategy scheme for reef-building corals developed by Darling et al. (Ecol Lett 15:1378–1386, 2012) and a long-term dataset of coral assemblage structure from inshore reefs on the central Great Barrier Reef. Several disturbances including mass bleaching and tropical storms were recorded in this 15-year interval from 1998 to 2013. ASG membership did not predict how a given taxon responded to disturbance. In fact, all ASGs were on average equally affected by bleaching and a period of multiple disturbances. Furthermore, there were no consistent winners at these sites in response to the 1998 bleaching in contrast to previous work suggesting clear hierarchies in susceptibility to bleaching. In conclusion, while further efforts to re-evaluate the utility of ASGs for reef corals should be encouraged our results and a re-examination of the literature suggests that direct trait-based approaches might prove more useful when exploring how corals respond to disturbance. [ABSTRACT FROM AUTHOR]

Photosystem II (PS II) pesticides, recognized as a threat to ecological health, were targeted for reduction in sugarcane farming in Great Barrier Reef (GBR) catchments. Alternative herbicides, the non-PS II herbicides (including glyphosate, paraquat, 2,4-D, imazapic, isoxaflutole, metolachlor, and S-metolachlor), continue to be used in these catchments. However, the potential ecological fate, transport, and off-site environmental effects of non-PS II herbicides, with respect to their usage scheme, local rainfall patterns, and infiltration dynamics, have not been investigated previously. A vadose zone monitoring system, instrumented beneath sugarcane land in a GBR catchment, was applied for real-time tracing of pesticide migration across the unsaturated zone, past the root zone during 2017–2019. The regularly applied pesticides (fluroxypyr and isoxaflutole) exhibited substantial migration through the unsaturated zone. Within 1 month of application of fluroxypyr, it leached to 2.87 m depth in the vadose zone, with declining concentrations with depth. Isoxaflutole, which was applied yearly, was found only once, in November 2018, at 3.28 m depth in the soil profile. Other pesticides (imazapic, metolachlor, glyphosate, and haloxyfop) applied during the same period were not detected in the vadose zone. However, imidacloprid, which was not applied at the site during the monitored period, was detected across the entire vadose zone, revealing substantial resistance to degradation. The results show no evidence of any regularly applied pesticides in the site bores at the end of the study, indicating their ultimate degradation within the vadose zone before reaching the groundwater. [ABSTRACT FROM AUTHOR]

Complex color patterning is a characteristic feature of dwarf minke whales (DMWs; Balaenoptera acutorostrata) which has been used to photographically identify (photo‐ID) individuals and to research an aggregation on Australia's Great Barrier Reef (GBR). DMW color patterns have been described and applied in various studies, but a detailed and systematic analysis of their complexity is yet to be performed. Here, we applied a novel categorization tool to assess the variation, asymmetry, and association of several DMW color pattern elements, subelements, and their character states. Proportions, hierarchical clustering, and multiple correspondence analysis revealed a high level of asymmetric color pattern variation, with white markings dominant and associated on the right of the body. Our results will improve the citizen science driven photo‐ID of this little‐known cetacean as labor‐intensive manual methods transition to more efficient automated approaches. Such advancement will be challenging, yet beneficial for broader research into the poorly understood areas of DMW life history, evolution, genetics, social structure, and feeding. This could also potentially allow investigation into the functional significance of their color patterns. [ABSTRACT FROM AUTHOR]

The majority of tourists who visit Australia's Great Barrier Reef (GBR) engage in snorkelling. Yet little is known about how snorkellers perceive this experience. The aim of this study was to investigate snorkeller behaviour by exploring their environmental opinions and to provide insights on the association between climate concerns and environmentally conscious behaviours of snorkellers. A selfadministered questionnaire (n = 273) was distributed onboard reef tourism vessels visiting the study area. Approximately one-third of respondents believe that climate change and global warming are major threats to the GBR. Regression results indicate the environmentally conscious behaviour model (ECBM), a modified version of the norm activation model, is effective in understanding how a snorkeller's level of climate concern (LCC) both directly and indirectly activates and influences a snorkeller's environmentally conscious behaviour (ECB). LCC has a positive direct effect on ECB, and a positive indirect effect via environmental identity (EI), and personal environmental norms (PEN). [ABSTRACT FROM AUTHOR]

Coral reef ecosystems are expected to undergo significant declines over the coming decades as oceans become warmer and more acidic. We investigate the environmental tolerances of over 650 Scleractinian coral species based on the conditions found within their present‐day ranges and in areas where they are currently absent but could potentially reach via larval dispersal. These "environmental envelopes" and connectivity constraints are then used to develop global forecasts for potential coral species richness under two emission scenarios, representing the Paris Agreement target ("SSP1‐2.6") and high levels of emissions ("SSP5‐8.5"). Although we do not directly predict coral mortality or adaptation, the projected changes to environmental suitability suggest considerable declines in coral species richness for the majority of the world's tropical coral reefs, with a net loss in average local richness of 73% (Paris Agreement) to 91% (High Emissions) by 2080–2090 and particularly large declines across sites in the Great Barrier Reef, Coral Sea, Western Indian Ocean, and Caribbean. However, at the regional scale, we find that environmental suitability for the majority of coral species can be largely maintained under the Paris Agreement target, with 0%–30% potential net species lost in most regions (increasing to 50% for the Great Barrier Reef) as opposed to 80%–90% losses under High Emissions. Projections for subtropical areas suggest that range expansion will give rise to coral reefs with low species richness (typically 10–20 coral species per region) and will not meaningfully offset declines in the tropics. This work represents the first global projection of coral species richness under oceanic warming and acidification. Our results highlight the critical importance of mitigating climate change to avoid potentially massive extinctions of coral species. [ABSTRACT FROM AUTHOR]

Parrotfish are key agents of bioerosion and sediment production in coral reef ecosystems; however, their dietary targets and therefore potential sources of variation in carbonate cycling lack resolution. Here we address this knowledge shortfall in our current understanding of parrotfish diets by testing the concept that protein-rich micro-photoautotrophs are the target prey for many Scarinine parrotfishes. We focus at fine spatial scales on the feeding substrata of 12 syntopic Indo-Pacific parrotfish species at mid-shelf sites around Lizard Island, Great Barrier Reef, Australia. We followed individual parrotfish on snorkel until biting was observed, and then extracted a reef core around each bite. The surface of each bite core was scraped to ~1 mm for quantitative microscopic analysis (up to 630 × magnification) and for 16S and 18S rRNA metabarcoding. The most dominant photoautotrophic group in terms of surface cover was filamentous cyanobacteria, followed by crustose coralline algae. Epiphytic, epilithic, endophytic and endolithic filamentous cyanobacteria were consistent bite core biota. Although the density of filamentous cyanobacteria on bite cores was largely consistent among the 12 parrotfish species, the quantitative microscopic data and rRNA metabarcoding revealed distinct differences between parrotfish species in the taxonomic composition of core biota. Our data provide further evidence that these syntopic parrotfish species partition feeding resources. [ABSTRACT FROM AUTHOR]

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sponges host a wide range of cryptic biodiversity both internally and externally. This study quantified the biodiversity inhabiting, or associated with, three morphologically distinct coral reef sponges. Coelocarteria singaporensis, Coscinoderma mathewsi and Ircinia microconulosa were collected from fringing reefs at Orpheus Island, central Great Barrier Reef, across monsoonal seasons (wet and dry) and diurnal periods (morning, afternoon and night for C. singaporensis) to quantify Sponge Associated Biota (SAB). A total of 8489 SAB was sorted from 77 sponges. Twenty‐six taxa, across 3 kingdoms and 12 phyla were recorded. Sponge‐associated biota was dominated by Mollusca in all three sponge hosts (range ~ 46%–50%) but taxa were found from a number of other phyla including, Arthropoda, Annelida, Echinodermata, Cnidaria, Foraminifera and Nemertea. There was no effect of season on abundances of SAB within the three species of sponge, but there was a significant effect associated with sponge host species, driven by a higher number of SAB in C. singaporensis and I. microconulosa. The diurnal patterns of SAB within C. singaporensis showed consistent abundances of mobile invertebrate groups with molluscs, echinoderms and arthropods dominating these samples. This study also highlights the ecological role and contribution of SAB in the reef ecosystems. [ABSTRACT FROM AUTHOR]