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Coral reef bleaching events have become more frequent all over the world and pose a serious threat to coral reef ecosystems. Therefore, there is an urgent need for better detection of coral reef bleaching in a time- and cost-saving manner. In recent years, remote sensing technology has often been utilized and gained recognition for coral reef bleaching detection. However, bleaching corals in the water always have weak spectral change signals, causing difficulties in using remote sensing data. Additionally, uneven change samples make it challenging to adequately capture the details of coral reef bleaching detection and produce thematic maps. To resolve these problems, a novel method named coral reef bleaching detection by positive-unlabeled bagging (CBD-PUB) is proposed in this paper. To test the capacity of the method, a series of multi-temporal Sentinel-2 remote sensing images are utilized, and Lizard Island in Australia is taken as a case study area. The pseudo-invariant feature atmospheric correction (PIF) algorithm is adopted to improve coral reef bleaching spectral signals. After that, CBD-PUB is employed to effectively explore coral reef bleaching variation and its corresponding influence relations. The experimental results show that the overall accuracy of bleaching detection by the proposed algorithm reaches 92.1% and outperforms the traditional method. It fully demonstrates the feasibility of the model for the field of coral reef bleaching detection and provides assistance in the monitoring and protection of coral environments. [ABSTRACT FROM AUTHOR]

Optimal design facilitates intelligent data collection. In this paper, we introduce a fully Bayesian design approach for spatial processes with complex covariance structures, like those typically exhibited in natural ecosystems. Coordinate exchange algorithms are commonly used to find optimal design points. However, collecting data at specific points is often infeasible in practice. Currently, there is no provision to allow for flexibility in the choice of design. Accordingly, we also propose an approach to find Bayesian sampling windows, rather than points, via Gaussian process emulation to identify regions of high design efficiency across a multi-dimensional space. These developments are motivated by two ecological case studies: monitoring water temperature in a river network system in the northwestern United States and monitoring submerged coral reefs off the north-west coast of Australia. [ABSTRACT FROM AUTHOR]

This article summarises the careers of ten women who have made an amazing contribution to our knowledge of Australian coral reefs and their management, and how this contribution has been used by the Great Barrier Reef Committee (subsequently the Australian Coral Reef Society) to conserve and manage our reefs—an ongoing process in the face of climate change. This paper highlights the critical role that women have played in Australian coral reef science over the last 90 years, through documenting the biodiversity, ecology and functioning of coral reefs. The scientific contributions of ten outstanding women are summarised, along with how they broke down barriers by working on oceanographic vessels and undertaking research in remote areas, while also using their expertise to advocate for the management and conservation of Australia's diverse coral reefs. [ABSTRACT FROM AUTHOR]

Vietnamese 'blue boats' – small wooden‐hulled fishing boats – are now entering the territorial waters of Pacific Island countries and illegally catching high‐value species found on remote coastal reefs. Crossing several international boundaries and traversing a distance of over 5000 km, these intrusions have alarmed Oceanic countries, including Australia. Lacking administrative capacity as well as jurisdictional authority to effectively control the vast stretches of island coastlines individually, governments and intergovernmental bodies in the region have called for strengthened coordination of surveillance efforts while also pressuring Vietnam diplomatically. This paper reviews these latest developments and is the first to provide a focused assessment of the issue. Through the lens of Copenhagen School of securitisation theory, we analyse responses of national and regional actors and their portrayal in online media to understand how blue boats are constructed as a security threat within a narrative of maritime, food and human security. Arguably, Australia together with the Forum Fisheries Agency, who advise on the governance of offshore tuna resources, have so far acted most decisively – in a way that might see them extend their strategic role in the region. We propose a comprehensive empirical research agenda to better understand and manage this nascent, flammable and largely unpredictable inter‐regional phenomenon. [ABSTRACT FROM AUTHOR]

Scleractinian corals are colonial animals with a range of life‐history strategies, making up diverse species assemblages that define coral reefs. We tagged and tracked ~30 colonies from each of 11 species during seven trips spanning 6 years (2009–2015) to measure their vital rates and competitive interactions on the reef crest at Trimodal Reef, Lizard Island, Australia. Pairs of species were chosen from five growth forms in which one species of the pair was locally rare (R) and the other common (C). The sampled growth forms were massive (Goniastrea pectinata [R] and G. retiformis [C]), digitate (Acropora humilis [R] and A. cf. digitifera [C]), corymbose (A. millepora [R] and A. nasuta [C]), tabular (A. cytherea [R] and A. hyacinthus [C]) and arborescent (A. robusta [R] and A. intermedia [C]). An extra corymbose species with intermediate abundance, A. spathulata was included when it became apparent that A. millepora was too rare on the reef crest, making the 11 species in total. The tagged colonies were visited each year in the weeks prior to spawning. During visits, two or more observers each took two or three photographs of each tagged colony from directly above and on the horizontal plane with a scale plate to track planar area. Dead or missing colonies were recorded and new colonies tagged to maintain ~30 colonies per species throughout the 6 years of the study. In addition to tracking tagged corals, 30 fragments were collected from neighboring untagged colonies of each species for counting numbers of eggs per polyp (fecundity); and fragments of untagged colonies were brought into the laboratory where spawned eggs were collected for biomass and energy measurements. We also conducted surveys at the study site to generate size structure data for each species in several of the years. Each tagged colony photograph was digitized by at least two people. Therefore, we could examine sources of error in planar area for both photographers and outliners. Competitive interactions were recorded for a subset of species by measuring the margins of tagged colony outlines interacting with neighboring corals. The study was abruptly ended by Tropical Cyclone Nathan (Category 4) that killed all but nine of the more than 300 tagged colonies in early 2015. Nonetheless, these data will be of use to other researchers interested in coral demography and coexistence, functional ecology, and parametrizing population, community, and ecosystem models. The data set is not copyright restricted, and users should cite this paper when using the data. [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]

Sustainable destinations must deliver products that perform better than their competitors and at the same time protect key environmental drawcards. This research explores the environmental–economic interface of a major destination, both as a case study in how to approach this complex relationship and as a contribution to the methodology of tackling the need for understanding competitive pressures as part of sustainable tourism strategy creation. Using the Great Barrier Reef World Heritage Area (GBRWHA) as an example, the paper assesses 21 key environmental values, including Indigenous culture, against market-based factors, in terms of their importance for visitors as regional drawcards, satisfaction with them and the way in which changes in them might affect trip numbers and duration across different regions. While the natural values of the GBRWHA are found to be the most important drawcards, satisfaction scores were significantly lower than importance scores for a number of these values. Visitors responded more negatively to the prospect of environmental degradation than to the prospect of a 20% increase in local prices: the detailed impact depends, however, on location and visitor mix. Clear ocean, healthy coral reefs, healthy reef fish, and lack of rubbish were the top four most important values. [ABSTRACT FROM PUBLISHER]

The Great Barrier Reef (GBR), Queensland, Australia, is one of the most recognisable coral reefs in the world. In 1981 the reef was listed on the World Heritage List, to be preserved as an environmental asset of global significance for all people in perpetuity. The GBR is also a landmark Marine Protected Area (MPA) under the World Heritage Marine Programme. Yet management of this iconic property is not without controversy and in recent years a number of impacts, including coastal developments, increased shipping traffic and global warming, have all threatened the reef. Any breach of Australia's World Heritage obligation to protect and conserve the property may yet result in the GBR being placed on the World Heritage List in Danger. In light of the persistent controversy surrounding GBR management, this paper gives voice to the perspectives and values of stakeholders located in and around one site of controversy, Gladstone Harbour, in the southern section of the GBR World Heritage Area. We present the views of users directly exposed to the controversial port expansion development at Gladstone Harbour in the southern GBR to shed light on the importance of community perspectives in marine park management. Our findings show that local views act to reinforce the global environmental protection narrative which underpins the World Heritage (WH) system. In this study local and global values collide and, we argue, that overlooking the perspectives of users has potential deleterious consequences for WH marine site management. [ABSTRACT FROM AUTHOR]

Duce, S., Vila-Concejo, A., Hamylton, S., Bruce, E., Webster, J. M, 2014. Spur and groove distribution, morphology and relationship to relative wave exposure, Southern Great Barrier Reef, Australia. In: Green, A.N. and Cooper, J.A.G. (eds.), Proceedings 13th International Coastal Symposium (Durban, South Africa), Journal of Coastal Research, Special Issue No. 70, pp. 115-120, ISSN 0749-0208. Spur and groove features occur on the seaward reef slope of coral reefs around the world. They are believed to act as important natural breakwaters, regulating the hydrodynamic energy and nutrients received by reef platforms. They also represent one of the most diverse and productive zones of modern reefs. However, the formation processes and morphodynamics of spur and groove systems are poorly understood, particularly in the Great Barrier Reef (GBR). This paper constitutes the first broad scale analysis of spur and groove systems in the Capricorn Bunker Group (CBG) in the southern GBR. It uses remotely sensed imagery coupled with ground-truthed data to measure groove length at four reefs (Wreck, Heron, One Tree and Lady Elliot). A total of 2621 grooves were digitised across the four study reefs. Groove length was found to vary both between and within the study reefs. The maximum groove length was 536 m. Average groove length ranged from 93 m at Wreck Reef to 32 m at Heron Reef. This data was compared to relative wave exposure estimates derived from the fetch scenario at each reef. Strong positive correlation was found with groove length increasing as wave exposure increased. Groove length was highly spatially dependant and varied around the reef platforms according to the degree of wave exposure. The longest grooves were found on the most exposed, eastern sides of all reefs. These results provide valuable insight into spur and groove function, formation and likely response to future environmental changes in the CBG and further afield. [ABSTRACT FROM AUTHOR]

This paper addresses uncertainty in socio-economic and sediment-nutrient models that are being developed for the assessment of change in the Great Barrier Reef (GBR) area. The catchments draining into the GBR lagoon are sources of pollutants. The Reef Water Quality Management Plan of the Queensland Government identified sediments and nutrients transported to the GBR lagoon as the major long-term threats to the reef and inshore ecosystems and the wellbeing of the human communities. The plan clearly indicates that changes in land management are required by 2013 to reduce pollutant inputs and, at the same time, maintain or enhance the benefits from using the inland waters. Science that provides decision tools for natural resource management and improves socio-economic and biophysical understanding is required to enable managers to make better decisions. A major research activity (the Water for a Healthy Country Flagship) aims to address social, economic and biophysical outcomes of land management change in the GBR. It contains research activities that provide information for integrated model development. Currently, however, these models lack the ability to estimate the uncertainty associated with prediction. This project aims to provide statistical methods for assessing uncertainty in models of sediment transportation to the GBR. Furthermore, it provides a link between the models and the decision-making process that allows assessment of uncertainty, a step pertinent to the risk analysis of policy options. This paper describes current and ongoing approaches for assessing uncertainty using a sediment modelling example and provides a way forward for the integration of applied socio-economic and biophysical models used in the decision-making process. [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]

Marine and coastal biodiversity is crucial to the planet's functioning and offers ecosystem services that guarantee the health, wealth, and well-being of the entire humanity. This is why, evaluating the current body of research on coral reefs is essential for understanding the unprecedented growth of this field, which covers many topics including climate change, biotic interactions, bioresources, future bioprospecting, and biodiversity in general. Such an evaluation requires both descriptive summaries and co-citation analyses to understand the expansive nature of this particular research and identify research gaps. Given the importance of the topic and the fact that it is insufficiently addressed, this study fills in a gap regarding coral reefs studies. We analyzed coral reef research published in the Web of Science Core Collection database between 1970 and 2021, using the CiteSpace software. This gave a total of 20,362 records, focusing on variables including the list of contributors (author, affiliation, and country), total publications over time, dual map overlay, co-citation analysis (co-cited author and documents), cluster networks, and popular keywords and their burstness. We found that coral reef publications increased over time, with coastal countries (the USA, Australia, and Japan) being among the highest contributors. Researchers from Australia, New Zealand, and the USA are the top producers of coral reef research worldwide. Unsurprisingly, the journal Coral Reefs was the most productive journal. Interestingly, we found that keywords such as "great barrier reef," "climate change," and "predation" were among the top cited and most influential in coral reef science. To our knowledge, this is the first study to identify trends in coral reef research using scientometric analyses based on the CiteSpace software. [ABSTRACT FROM AUTHOR]

Egg case nurseries of the boreal skate (Amblyraja hyperborea) and Richardson's skate (Bathyraja richardsoni) were defined and mapped on a bathyal seascape (c. 500–1900 m depths) south of Tasmania, Australia, using 99 towed‐camera transects (157 linear km; N = 50,858 images). In total, 738 skate egg cases were observed (present in 240 images, absent in 50,618); among 113 egg cases examined to identify parent species, 70% were A. hyperborea, 10% B. richardsoni and 20% unidentified Bathyraja species. "Recently laid" egg cases were differentiated from "aged" ones by classifying their colour and condition. The great majority (98%) of egg cases were observed in c. 1100–1400 m depths on seamounts (15 of 36 surveyed), not seamount bases or adjacent continental slope. Egg cases were associated with reefs formed by accumulated skeletal matrix of the stony coral Solenosmilia variabilis, with >90% egg cases (including most of those recently laid) observed on living S. variabilis that characterises a "coral zone" in c. 950–1350 m depths. Water in the coral zone is warmer (+0.66 to 2.37°C) than at the deep distributional limits of adult A. hyperborea and B. richardsoni (2000 and 3000 m, respectively), potentially providing for accelerated embryonic development. Co‐occurrence with living coral infers an energetically favourable local‐scale hydrodynamic environment for egg cases, particularly on seamount peaks, where increased water flow over egg cases would avert smothering by suspended sediment, and compensate for lower oxygen concentration compared to deeper depths occupied by adult skates. Criteria identifying egg case nurseries are strongly met for A. hyperborea at Seamount Z110 (468 egg cases of varied ages, maximum density of 5.47 m−2) and to a lesser extent on five others (Seamounts K1, Z16, Hill U, Z5 and Hill V). An abundance (density) criterion for defining nurseries needs to be flexible because it is a spatially scale‐dependent measure that differs between surveys according to the tools and design employed. Off Australia, coral reef egg case nursery habitat is restricted to a narrow depth range in temperate latitudes where it is scarce and impacted by historical bottom trawl fishing in many locations. There has been effective conservation of nursery habitat, however, because four of the six nursery sites identified here and extensive coral reef areas are protected within marine parks. [ABSTRACT FROM AUTHOR]

Temperate reefs are at the forefront of warming-induced community alterations resulting from poleward range shifts. This tropicalisation is exemplified and amplified by tropical species' invasions of temperate herbivory functions. However, whether other temperate ecosystem functions are similarly invaded by tropical species, and by what drivers, remains unclear. We examine tropicalisation footprints in nine reef fish functional groups using trait-based analyses and biomass of 550 fish species across tropical to temperate gradients in Japan and Australia. We discover that functional niches in transitional communities are asynchronously invaded by tropical species, but with congruent invasion schedules for functional groups across the two hemispheres. These differences in functional group tropicalisation point to habitat availability as a key determinant of multi-species range shifts, as in the majority of functional groups tropical and temperate species share functional niche space in suitable habitat. Competition among species from different thermal guilds played little part in limiting tropicalisation, rather available functional space occupied by temperate species indicates that tropical species can invade. Characterising these drivers of reef tropicalisation is pivotal to understanding, predicting, and managing marine community transformation. This study examines how the tropicalisation of shallow reefs changes functional niches for fishes in Japan and Australia. They discover that functional niches in tropical-temperate transitional communities are asynchronously invaded by tropical species, mediated more by habitat availability than competition with resident temperate species. [ABSTRACT FROM AUTHOR]

The short spined crown-of-thorns starfish Acanthaster brevispinus inhabits deeper water soft bottom habitats, in contrast to the more infamous Indo-Pacific Acanthaster species complex of which population outbreaks have been responsible for widespread coral mortality throughout the Indo-West Pacific region. Acanthaster brevispinus has not previously been regarded as a threat to corals or coral reefs. Here, we report A. brevispinus occurring on mesophotic off-reef or inter-reef habitats in 20–70-m depths dominated by solitary corals off both the western and eastern coasts of Australia. On Ningaloo Reef, A. brevispinus were found on mushroom coral (Cycloseris distorta) beds using an underwater towed camera and further exploration using a remotely operated vehicle (ROV) confirmed predation by A. brevispinus on C. distorta. On the southern Great Barrier Reef, A. brevispinus in large numbers were found in habitat dominated by the dendrophylliid Heteropsammia cf. cochlea. Predation on H. cf. cochlea was also directly observed. This is the first confirmed report of predation on hard corals by A. brevispinus, and while there are yet to be any records of population outbreaks of this species, such outbreaks could have a significant effect on mesophotic solitary coral assemblages. [ABSTRACT FROM AUTHOR]

On the 100-year anniversary of the Australian Coral Reef Society (ACRS), previously known as the Great Barrier Reef Committee (GBRC), we provide an overview of ACRS activities throughout its history, with a detailed account of key milestones in the last 40 years. We outline how the ACRS as promoted the protection and conservation of reefs, through expert advice, reviews, and submissions to enquiries. Examples are provided under the following themes: ACRS consultancy on zoning the Great Barrier Reef (GBR) Marine Park, marine protected area design, water quality on the GBR, port expansions along the Queensland coastline and environmental reform for the offshore oil and gas industry. We illustrate how scientists over recent decades have worked to better understand and encourage policy responses to the impacts of climate change on Australia's coral reefs. For a hundred years, the GBRC-ACRS has provided an avenue for Australian coral reef scientists, managers and conservationists to influence reef governance through policy. While these unique avenues for delivering timely and targeted expertise have helped to reduce proximate threats to reefs at local scales, their outcome in relation to climate change, arguably the largest threat to Australia's coral reefs, remains to be seen. We review ACRS activities under the following themes: consulting on the Capricorn Bunker Group to zone the Great Barrier Reef Marine Park, marine protected area design, water quality on the GBR, Queensland port expansions, environmental reform for the offshore oil and gas industry and the impacts of climate change on Australian reefs. We outline how the ACRS has promoted the exchange of scientific information to protect and conserve Australian reefs for a 100 years. [ABSTRACT FROM AUTHOR]

The Thalasseleotrididae is a small family of exclusively marine gobioids. They form a sister taxon to the Gobiidae and Oxudercidae and are distinguished from most species in these families by having six branchiostegal rays and a membrane linking the hyoid arch to the first ceratobranchial. Here we use micro-CT informed morphological data and molecular phylogenetics to describe a new genus and species of thalasseleotridid discovered on a tropical oceanic coral reef in the central Coral Sea. Tempestichthys bettyae gen. et sp. nov. is the first tropical thalasseleotridid and differs from other members of the Thalasseleotrididae by having a T-shaped palatine and a distinctive shape and colouration. The three previously described thalasseleotridid species are endemic to temperate coastal waters of southern Australia and New Zealand and are all translucent brown with dorsoventrally compressed heads. However, Tempestichthys bettyae is laterally compressed with a pointed snout and is translucent white with opaque white and crimson red markings and a largely crimson iris. We discuss the unique characters of this new genus, including its distribution, form, colouration and diminutive size, and highlight the potential of there being undescribed diversity in the Thalasseleotrididae. [ABSTRACT FROM AUTHOR]

While coral reefs in Australia have historically been a showcase of conventional management informed by research, recent declines in coral cover have triggered efforts to innovate and integrate intervention and restoration actions into management frameworks. Here we outline the multi-faceted intervention approaches that have developed in Australia since 2017, from newly implemented in-water programs, research to enhance coral resilience and investigations into socio-economic perspectives on restoration goals. We describe in-water projects using coral gardening, substrate stabilisation, coral repositioning, macro-algae removal, and larval-based restoration techniques. Three areas of research focus are also presented to illustrate the breadth of Australian research on coral restoration, (1) the transdisciplinary Reef Restoration and Adaptation Program (RRAP), one of the world's largest research and development programs focused on coral reefs, (2) interventions to enhance coral performance under climate change, and (3) research into socio-cultural perspectives. Together, these projects and the recent research focus reflect an increasing urgency for action to confront the coral reef crisis, develop new and additional tools to manage coral reefs, and the consequent increase in funding opportunities and management appetite for implementation. The rapid progress in trialling and deploying coral restoration in Australia builds on decades of overseas experience, and advances in research and development are showing positive signs that coral restoration can be a valuable tool to improve resilience at local scales (i.e., high early survival rates across a variety of methods and coral species, strong community engagement with local stakeholders). RRAP is focused on creating interventions to help coral reefs at multiple scales, from micro scales (i.e., interventions targeting small areas within a specific reef site) to large scales (i.e., interventions targeting core ecosystem function and social-economic values at multiple select sites across the Great Barrier Reef) to resist, adapt to and recover from the impacts of climate change. None of these interventions aim to single-handedly restore the entirety of the Great Barrier Reef, nor do they negate the importance of urgent climate change mitigation action. [ABSTRACT FROM AUTHOR]

Climate change threatens the survival of coral reefs on a global scale, primarily through mass bleaching and mortality as a result of marine heatwaves. While these short-term effects are clear, predicting the fate of coral reefs over the coming century is a major challenge. One way to understand the longer-term effect of rapid climate change is to examine the response of coral populations to past climate shifts. Coastal and shallow-water marine ecosystems such as coral reefs have been reshaped many times by sea-level changes during the Pleistocene, yet few studies have directly linked this with its consequences on population demographics, dispersal, and adaptation. Here we use powerful analytical techniques, afforded by haplotype-phased whole-genomes, to establish such links for the reef-building coral, Acropora digitifera. We show that three genetically distinct populations are present in northwestern Australia, and that their rapid divergence since the last glacial maximum (LGM) can be explained by a combination of founder-effects and restricted gene flow. Signatures of selective sweeps, too strong to be explained by demographic history, are present in all three populations and overlap with genes that show different patterns of functional enrichment between inshore and offshore habitats. In contrast to rapid divergence in the host, we find that photosymbiont communities are largely undifferentiated between corals from all three locations, spanning almost 1000 km, indicating that selection on host genes, and not acquisition of novel symbionts, has been the primary driver of adaptation for this species in northwestern Australia. [ABSTRACT FROM AUTHOR]

Time series data are often observed in ecological monitoring. Frequently, such data exhibit nonlinear trends over time potentially due to complex relationships between observed and auxiliary variables, and there may also be sudden declines over time due to major disturbances. This poses substantial challenges for modeling such data and also for adaptive monitoring. To address this, we propose methods for finding adaptive designs for monitoring in such settings. This work is motivated by a monitoring program that has been established at Scott Reef; a coral reef off the Western coast of Australia. Data collected for monitoring the health of Scott Reef are considered, and semiparametric and interrupted time series modeling approaches are adopted to describe how these data vary over time. New methods are then proposed that enable adaptive monitoring designs to be found based on such modeling approaches. These methods are then applied to find future monitoring designs at Scott Reef where it was found that future information gain is expected to be similar across a variety of different sites, suggesting that no particular location needs to be prioritized at Scott Reef for the next monitoring phase. In addition, it was found that omitting some sampling sites/reef locations was possible without substantial loss in expected information gain, depending upon the disturbances that were observed. The resulting adaptive designs are used to form recommendations for future monitoring in this region, and for reefs where changes in the current monitoring practices are being sought. As the methods used and developed throughout this study are generic in nature, this research has the potential to improve ecological monitoring more broadly where complex data are being collected over time. [ABSTRACT FROM AUTHOR]

Movement studies on marine animals can inform conservation and fishery management planning through data that explain likely dispersals and home‐ranging behaviours. Relatively few studies are documented for exploited marine invertebrates, despite many having a high ecological and commercial value. We assessed the diurnal movement patterns of Thelenota ananas and Thelenota anax, the world's largest sea cucumbers, which are highly exploited throughout the Indo‐Pacific. At two coral reef sites at Lizard Island, northern Australia, we tracked the 2‐hourly displacement of individuals from morning to nightfall. Movement of T. ananas was more reef‐associated and tortuous than T. anax. Displacement rates averaged 80 cm h−1 (±8 SE) for T. ananas and 73 cm h−1 (±20) for T. anax. Body size accounted for half of the variation in displacement for T. ananas. Mobility peaked in the late afternoon or early evening for both species, and animals tended to reverse their direction of travel after midday. The data reflect a pattern of animals meandering out from their reef shelters onto sandy lagoon floors to forage, before returning to the reefs. This empirical evidence offers further support that these holothuroids contribute to the formation of "reef halos". The exceptionally high movement rates and patterns found in this study should inform the design of spatial management measures. [ABSTRACT FROM AUTHOR]

The coral reefs of the Kimberley bioregion are situated in an area that is considered a significant ‘biodiversity hotspot’ and are poorly known and of recognised international significance. This paper is a review of ongoing research as part of one of the first geoscientific reef studies of the Kimberley Biozone. Remote sensing, sub-bottom profiling and associated sedimentological work have been employed to produce a regional geodatabase of coral reefs and determine the Holocene internal architecture and growth history of the coral reefs. Satellite image analysis has revealed that fringing reefs in the Kimberley bioregion grow very well and differ geomorphologically from planar reefs both inshore and offshore. The acoustic profiles have depicted multiple reef build-ups, demonstrating the reefs’ long-term resilience. This research has provided a better understanding of the Kimberley reefs and demonstrated their capacity to succeed in challenging environments and generate habitats characterised by high complexity and species diversity. [ABSTRACT FROM PUBLISHER]

Marine-oriented nature-based tourism plays an important socio-economic role, and provides an incentive for conservation in many coastal regions. However, accelerating global change, and the associated socio-economic and political change may have severe consequences for marine tourism at the local level. Thus, understanding the ability of sectors within marine tourism to cope with, and adapt to, change is paramount. Private sector enterprises are key players in marine tourism and their capacity to adapt to change will vary across socio-economic and governance contexts. Thus, the resilience of these enterprises (their ability to adapt to, and continue to function under changing pressures and circumstances) is critical for the future of the marine tourism sector more broadly. This paper examines how socioeconomic and governance contexts influence the resilience of coral reef tourism enterprises in three settings: the formal and informal sector in Phuket, Thailand and enterprises on Australia's Great Barrier Reef. Although there are differences between the three groups of enterprises, lifestyle factors, human capital, perceived reef condition, and government support are associated with the resilience of enterprises across all three groups. These findings suggest that policy-makers should consider enterprise lifestyle benefits, and that a nuanced understanding of marine tourism enterprises is required. [ABSTRACT FROM AUTHOR]

Abstract: In the management of recreational fishing, multiple biophysical and socio-economic objectives need to be considered. The identification of best management options is technically challenging because of the lack of scientific tools to inform resource managers of future responses/impacts of these different options. This paper proposes a decision support system which aims at greatly improving stakeholder dialogue and decision making. The system consists of two main components: an integrated agent-based model for simulating recreational fishing behavior and reef ecosystem dynamics; and an evaluation model based on the analytic hierarchy process (AHP) together with a technique for order preference by similarity to ideal solution (TOPSIS). The evaluation component is responsible for assessing alternative strategies based on the simulation outputs generated by the former. We apply the proposed system to the assessment of management strategies for recreational fishing in the Ningaloo Marine Park, an iconic coral reef system in Western Australia. A set of management strategies, including a “business-as-usual” strategy and six alternative site closure strategies are assessed using the proposed solution. The site closure strategies evaluated vary in length and number of popular sites closed. The evaluation results illustrate the usefulness of the proposed system in tackling complex management choices. We also perform a sensitivity analysis on the stakeholder or decision maker outcome preference weights and provide measures for assessing the sensitivity of strategy ranking outcomes to changes in these weights. [Copyright &y& Elsevier]

Understanding the resilience of vulnerable sectors of social-ecological systems is critical in an era of escalating global change. The coral reef tourism sector is highly vulnerable not only to ecological effects of climate change and other anthropogenic disturbances on reefs, but also to shocks such as economic recession and energy price escalation. Commercial tourism enterprises are key players in reef tourism in Australia and elsewhere. However, the factors that confer resilience to reef-based tourism enterprises, or the reef tourism sector more broadly, in the face of large disturbances have not been investigated to date. This paper empirically examines the perceived resilience of reef tourism enterprises on Australia's Great Barrier Reef to large disturbances or shocks. Binary logistic regression analysis of two measures of enterprise resilience demonstrates the importance of human capital in strengthening enterprise resilience. lifestyle identity, measured as the extent to which owners and senior managers are active in reef tourism as a lifestyle choice, is positively related to enterprise resilience. Finally, reef tourism enterprises indicate that financial and marketing support are the most important actions that government can take to support enterprises in the face of a large shock. [ABSTRACT FROM AUTHOR]

Abstract: Sediment accumulation rate is a frequently required parameter in environmental and management studies, in particular near coral reefs where sediment accumulation can potentially cause severe impact. However, opportunities to obtain accurate sediment accumulation measurements are often limited by a lack of adequate instrumentation, in particular for high temporal resolution monitoring. For instance the traditional use of sediment traps, as the most widespread technique, offers poor temporal resolution (commonly of weeks) besides having significant hydrodynamic shortcomings. Therefore, a new optical backscatter sediment accumulation sensor (SAS) was developed to continuously measure in situ short-term sediment accumulation in sensitive riverine and coastal environments, enabling high temporal and vertical resolution (order of 1h and with a deposited thickness resolution in the order of 20μm respectively). This allows investigations of various parameters that influence accumulation: tides, current, waves, rain, or anthropogenic activity such as sediment dumping. This paper briefly describes the SAS and presents three field applications on nearshore coral reefs at Ishigaki Island (Japan), Lihir Island (Papua New Guinea), and Magnetic Island (Australia). [Copyright &y& Elsevier]

Patterns of reproductive ontogeny in four species of coral reef wrasses (F: Labridae) Hemigymnus melapterus, Hemigymnus fasciatus, Cheilinus fasciatus and Oxycheilinus digramma were investigated. Populations of each species were sampled from two island groups of the central Great Barrier Reef (GBR), Australia, and from coral reefs in the central Philippines. These three sampling locations span 30° of latitude. The GBR and Philippine reefs experience biologically significant differences in water temperature, geography and human activity. The studied wrasses are effectively unfished in Australia but heavily fished in the Philippines. Gonad weights, histology and demographic data were obtained across the entire size and age range of H. melapterus, C. fasciatus and O. digramma from all locations. Analysis identified three processes of male recruitment: functional gonochorism and both forms of protogynous hermaphroditism, monandry and diandry. The expression of these distinct sexual ontogenies was locality dependent. Populations of H. melapterus, H. fasciatus, C. fasciatus and O. digramma on the GBR showed consistently uniform patterns of sexual ontogeny, with all species being exclusively monandric. H. melapterus, C. fasciatus and O. digramma in the Philippines displayed complex sexual ontogenies, with all species showing histological evidence of both diandry and functional gonochorism. Reproductive investment in gonadal tissue, and population sex structure, also differed between GBR and Philippine coral reefs. Philippine populations had substantially lower gonado‐somatic indices than populations on the GBR. Nonetheless, Philippine populations matured more rapidly and displayed a protracted timing of sex change over a large size and age range. Thus, mature females appeared earlier and persisted later into ontogeny in the Philippines than on GBR reefs. Protracted timing of sex change on Philippine reefs is likely linked to the presence of primary males in the population, which is known to reduce the strength of selection for mature females to undergo sex change and become male. Hypotheses based on social structure of fish populations, environmental factors and evolutionary history were developed to account for the different patterns of sexual ontogeny in the focal wrasses. [ABSTRACT FROM AUTHOR]

Sponges in the subfamily Phyllospongiinae are important components of coral reefs. However, significant taxonomic inconsistencies exist in this group due to the lack of useful morphological characters for species delineation. This study assesses the systematics of some common phyllospongiinids in the genera Carteriospongia , Phyllospongia and Strepsichordaia from tropical Australia and the Red Sea, by using a multigene approach that utilizes the Internal Transcribed Spacer 2, the complete ribosomal 18S rRNA and three 28s rRNA gene regions (D1‒D2, D3‒D5 and D6‒D8), which produced a phylogenetic framework in which complementary morphological taxonomic assessments were performed. Type specimens were included, where available, and six species clades were recovered, including the well-established Phyllospongia papyracea and Strepsichordaia lendenfeldi. Carteriospongia foliascens , the type species for the genus Carteriospongia, is transferred to the genus Phyllospongia , resulting in Carteriospongia becoming a synonym of Phyllospongia. Consequently, Carteriospongia flabellifera is removed from Carteriospongia and is reinstated to its original designation of Polyfibrospongia flabellifera. Two new species, Phyllospongia bergquistae sp. nov. and Polyfibrospongia kulit sp. nov. , are described. With phyllospongiinid sponges increasingly used as models for assessing the effects of climate change and anthropogenic stressors, this study provides a reliable systematics framework for the accurate identification of common phyllospongiinids across the Indo-Pacific. [ABSTRACT FROM AUTHOR]

Reef monitoring programmes often focus on limited sites, predominantly on reef slope areas, which do not capture compositional variability across zones. This study assessed spatial and temporal changes in hard coral cover at four hierarchical spatial scales. ~ 55,000, geo-referenced photoquadrats were collected annually from 2002 to 2018 and analysed using artificial intelligence for 31 sites across reef flat and reef slope zones on Heron Reef, Southern Great Barrier Reef, Australia. Trends in hard coral cover were examined at three spatial scales: (1) "reef scale", all data; (2) "geomorphic zone scale"—north/south reef slope, inner/outer reef flat; and (3) "site scale"—31 sites. Coral cover trajectories were also examined at: (4) "sub-site scale"—sub-division of sites into 567 sub-sites, to estimate variability in coral cover trajectories via spatial statistical modelling. At reef scale coral cover increased over time to 25.6 ± 0.4 SE % in 2018 but did not recover following disturbances caused by disease (2004–2008), cyclonic conditions (2009) or severe storms (2015) to the observed pre-disturbance level (44.0 ± 0.7 SE %) seen in 2004. At geomorphic zone scale, the reef slope had significantly higher coral cover than the reef flat. Trends of decline and increase were visible in the slope zones, and the southern slope recovered to pre-decline levels. Variable coral cover trends were visible at site scale. Furthermore, sub-site spatial modelling captured eight years of coral recovery that occurred at different times and magnitudes across the four geomorphic zones, effectively estimating variability in the trajectory of the reef's coral community. Derived spatial predictions for the entire reef show patchy coral recovery, particularly on the southern slope, and that recovery hotspots are distributed across the reef. These findings suggest that to fully understand and interpret coral decline or recovery on a reef, more accurate assessment can be achieved by examining sites distributed within different geomorphic zones to capture variation in exposure, depth and consolidation. [ABSTRACT FROM AUTHOR]

As marine heatwaves increasingly threaten coral reefs worldwide, some extreme reef environments naturally expose corals to high-temperature fluctuations and can therefore provide important insights into the mechanisms underlying coral heat tolerance. Coral reefs in the Kimberley region in northwest Australia experience the world's largest tropical tides and are therefore exposed to highly fluctuating temperatures in the intertidal. In contrast, the subtidal remains mostly submerged, resulting in moderate daily temperature fluctuations. A marine heatwave in 2016 triggered wide-spread bleaching in the Kimberley. Intertidal corals bleached less and recovered faster than adjacent subtidal corals; however, the mechanisms underlying this differential bleaching and recovery response remain poorly understood. Here we assessed both host- and symbiont-based indicators of bleaching resilience in the coral Acropora aspera. We tagged visibly healthy and bleached colonies from both environments in April 2016 and measured symbiont community composition, cell density, chlorophyll a, total biomass and host tissue energy reserves (lipids, protein and carbohydrates) during bleaching in April and in November 2016. Bleaching severity was higher in the subtidal than in intertidal, and while Cladocopium dominated all corals, symbiont community compositions differed significantly between environments and between bleached and healthy subtidal corals. Interestingly, bleaching resilience seemed decoupled from energy reserves, even though high levels of energy reserves and/or sufficient consumption during bleaching are widely thought to increase resistance to and recovery from bleaching. Although all bleached/recovered corals showed a general pattern of catabolizing protein reserves, distinct environment-specific trends were observed: subtidal corals that suffered extensive mortality also catabolized energy-poor carbohydrate reserves. In contrast, intertidal corals recovered rapidly after bleaching and maintained energy reserves. Total biomass remained unchanged between bleached and healthy corals in both environments. Overall, the findings of this study demonstrate that the consumption of energy reserves during bleaching is not always a reliable indicator of bleaching resilience. [ABSTRACT FROM AUTHOR]

Bioturbation of reef sediments aerates the upper sediment layers and releases organic material to benthic communities. Despite being the larger and more conspicuous bioturbators on coral reefs, the value of holothurians (sea cucumbers) to reef ecosystems is less often attributed to their ecosystem services than their value for fisheries. This may be because they are considered to have an insignificant effect on reef health relative to other animals. Here, we ground-truthed remote sensing data obtained from drone and satellite imagery to estimate the bioturbation rates of holothurians across the 19 km2 Heron Island Reef in Queensland, Australia. Ex situ bioturbation rates of the most abundant holothurian, Holothuria atra, were assessed during 24-h feeding experiments. Using density measurements of holothurians across reef flat zones in a 27,000 m2 map produced from drone imagery, we extrapolated bioturbation across the reef using satellite remote sensing data. Individual H. atra were estimated to produce approximately 14 kg of bioturbated sediment per year. On a reef scale (excluding the reef lagoon) and accounting for varying densities of holothurians across different reef zones, total bioturbation from holothurians at Heron Reef was estimated at over 64,000 metric tonnes per year, slightly more than the mass of five Eiffel Towers. These results highlight the scale of structural and biochemical impacts that holothurians have on reef flats and their importance to ecosystem functioning and services. Management of these animals on reefs is imperative as overharvesting would likely cause substantial negative effects on sedimentary ecosystems and their biogeochemistry in corals reefs. [ABSTRACT FROM AUTHOR]

Coral reefs are highly valued ecosystems currently threatened by both local and global stressors. Given the importance of coral reef ecosystems, a Bayesian network approach can benefit an evaluation of threats to reef condition. To this end, we used data to evaluate the overlap between local stressors (overfishing and destructive fishing, watershed‐based pollution, marine‐based pollution, and coastal development threats), global stressors (acidification and thermal stress), and management effectiveness with indicators of coral reef health (live coral index, live coral cover, population bleaching, colony bleaching, and recently killed corals). Each of the coral health indicators had Bayesian networks constructed globally and for Pacific, Atlantic, Australia, Middle East, Indian Ocean, and Southeast Asia coral reef locations. Sensitivity analysis helped evaluate the strength of the relationships between different stressors and reef condition indicators. The relationships between indicators and stressors were also evaluated with conditional analyses of linear and nonlinear interactions. In this process, a standardized direct effects analysis was emphasized with a target mean analysis to predict changes in the mean value of the reef indicator from individual changes to the distribution of the predictor variables. The standardized direct effects analysis identified higher risks in the Middle East for watershed‐based pollution with population bleaching and in Australia for overfishing and destructive fishing with living coral. For thermal stress, colony bleaching and recently killed coral in the Indian Ocean were found to have the strongest direct associations along with living coral in the Middle East. For acidification threat, Australia had a relatively strong association with colony bleaching, and the Middle East had the strongest overall association with recently killed coral, although extrapolated spatial data were used for the acidification estimates. The Bayesian network approach helped to explore the relationships among existing databases used for policy development in coral reef management by examining the sensitivity of multiple indicators of reef condition to spatially distributed stress. Integr Environ Assess Manag 2021;17:165–187. Published 2020. This article is a US Government work and is in the public domain in the USA. KEY POINTS: Coral reefs are high‐valued ecosystems at risk from diverse sources of stressors.A screening‐level risk assessment was conducted to examine the sensitivity of reef condition indicators to stressors.Comprehensive and cohesive global data sets on stressors and reef condition were integrated.Bayesian networks provided powerful tools for examining risks and spatial relationships. [ABSTRACT FROM AUTHOR]

Parrotfishes (Scarini) are considered key agents in coral reef health and recovery, but the drivers of parrotfish–coral dynamics remain contentious. The prevailing view of parrotfishes as ecosystem engineers is based on the perceived removal of algal turf, macroalgae and sediment, but these are effects of feeding, not causes. The recent proposal that most parrotfishes are 'microphages' that target microscopic photoautotrophs (particularly cyanobacteria) identifies the need to resolve dietary targets at a microscopic scale. Here, we investigate parrotfish dietary targets by posing the following two questions: (1) are microscopic photoautotrophs the most consistent and dominant elements of the prey community, and (2) do the prey community and substratum taphonomy vary between parrotfish species? In order to identify and quantify dietary targets, five parrotfish species were followed until focused feeding was observed at Lizard Island on the Great Barrier Reef, Australia. Feeding sites were photographed in situ and extracted as substratum bite cores. Cores were analysed microscopically to identify and quantify all epilithic photoautotrophs. Endolithic photoautotrophs accessible to excavating parrotfish were also investigated by vacuum-embedding cores with epoxy resin followed by decalcification to expose endolith microborings. The dominant functional groups of epilithic biota on the cores were tufted cyanobacteria, turfing algae and crustose coralline algae (CCA). The only consistent feature across all cores was the high density of filamentous cyanobacteria, supporting the view that these parrotfishes target microphotoautotrophs. Macroalgae was absent or a minor component on cores, supporting the hypothesis that parrotfishes avoid larger algae. The microchlorophyte Ostreobium was the dominant photoautotrophic euendolith (true borer) in the cores of the excavating parrotfish Chlorurus microrhinos. Significant differences in CCA coverage, turf height and substrate taphonomy were found among the five parrotfish species, suggesting that interspecific resource partitioning is based on successional stage of feeding substrata. [ABSTRACT FROM AUTHOR]

Two of Australia's most iconic ecosystems have recently sustained heavy damage related to climatic changes: the extensive eucalypt forests from catastrophic bushfires and the Great Barrier Reef from mass coral bleaching. Despite obvious differences, eucalypt trees and reef corals share some similarities in biology and ecology, particularly in relation to climate change impacts and adaptation. Both groups are the focus of an increasing research effort to characterize and respond to climate changes and here we examine how sharing research experiences can benefit both fields. Four key areas of research are considered: (a) modeling current distributions, (b) assessing impacts of climate change on future distributions, (c) using human‐assisted migration to improve survival, and (d) applying genetic enhancement to improve the species' survival. Examples of each research area are used to examine potential crossovers, limitations of the methods, and future requirements. We conclude that eucalypt and coral researchers, and indeed researchers for many other endangered taxa, can gain much by comparing experiences and methods, despite the apparent differences in their respective taxa. This article is categorized under: Assessing Impacts of Climate Change > Observed Impacts of Climate Change [ABSTRACT FROM AUTHOR]

We review the evidence for bio-regulation by coral reefs of local climate through stress-induced emissions of aerosol precursors, such as dimethylsulfide. This is an issue that goes to the core of the coral ecosystem's ability to maintain homeostasis in the face of increasing climate change impacts and other anthropogenic pressures. We examine this through an analysis of data on aerosol emissions by corals of the Great Barrier Reef, Australia. We focus on the relationship with local stressors, such as surface irradiance levels and sea surface temperature, both before and after notable coral bleaching events. We conclude that coral reefs may be able to regulate their exposure to environmental stressors through modification of the optical properties of the atmosphere, however this ability may be impaired as climate change intensifies. [ABSTRACT FROM AUTHOR]

Estimating the impact of environmental processes on vertical reef development in geological time is a very challenging task. pyReef-Core is a deterministic carbonate stratigraphic forward model designed to simulate the key biological and environmental processes that determine vertical reef accretion and assemblage changes in fossil reef drill cores. We present a Bayesian framework called Bayesreef for the estimation and uncertainty quantification of parameters in pyReef-Core that represent environmental conditions affecting the growth of coral assemblages in geological timescales. Weencounter multimodal posterior distributions and investigate the challenges of sampling using Markov chain Monte-Carlo (MCMC) methods, which includes parallel tempering MCMC. We use a synthetic reef-core to investigate fundamental issues and then apply the methodology to a selected reef-core from the Great Barrier Reef in Australia. The results show that Bayesreef accurately estimates and provides uncertainty quantification of the selected parameters that represent environment and ecological conditions in pyReef-Core. Bayesreef provides insights into the complex posterior distributions of the parameters in pyReef-Core , which provides the groundwork for future research in this area. • Estimating the impact of environmental processes on vertical reef development in geological time is a very challenging task. • pyReef-Core is a deterministic carbonate stratigraphic forward model designed to simulate the key biological and environmental processes. • This paper presents Bayesreef for the estimation and uncertainty quantification of parameters in pyReef-Core. • The results show that Bayesreef accurately estimates and provides uncertainty quantification for parameters in pyReef-Core. • Bayesreef provides insights in of pyReef-Core and establishes the groundwork for future research. [ABSTRACT FROM AUTHOR]

Tropical cyclones generate extreme waves that can damage coral reef communities. Recovery typically requires up to a decade, driving the trajectory of coral community structure. Coral reefs have evolved over millennia with cyclones. Increasingly, however, processes of recovery are interrupted and compromised by additional pressures (thermal stress, pollution, diseases, predators). Understanding how cyclones interact with other pressures to threaten coral reefs underpins spatial prioritization of conservation and management interventions. Models that simulate coral responses to cumulative pressures often assume that the worst cyclone wave damage occurs within ~100 km of the track. However, we show major coral loss at exposed sites up to 800 km from a cyclone that was both strong (high sustained wind speeds >=33 m/s) and big (widespread circulation >~300 km), using numerical wave models and field data from northwest Australia. We then calculate the return time of big and strong cyclones, big cyclones of any strength and strong cyclones of any size, for each of 150 coral reef ecoregions using a global data set of past cyclones from 1985 to 2015. For the coral ecoregions that regularly were exposed to cyclones during that time, we find that 75% of them were exposed to at least one cyclone that was both big and strong. Return intervals of big and strong cyclones are already less than 5 years for 13 ecoregions, primarily in the cyclone‐prone NW Pacific, and less than 10 years for an additional 14 ecoregions. We identify ecoregions likely at higher risk in future given projected changes in cyclone activity. Robust quantification of the spatial distribution of likely cyclone wave damage is vital not only for understanding past coral response to pressures, but also for predicting how this may change as the climate continues to warm and the relative frequency of the strongest cyclones rises. [ABSTRACT FROM AUTHOR]

Shallow, permeable calcium carbonate (CaCO3) sediments make up a large proportion of the benthic cover on coral reefs and account for a large fraction of the standing stock of CaCO3. There have been a number of laboratory, mesocosm, and in situ studies examining shallow sediment metabolism and dissolution, but none of these have considered seasonal variability. Advective benthic chambers were used to measure in situ net community calcification (NCC) rates of CaCO3 sediments on Heron Island, Australia (Great Barrier Reef) over an annual cycle. Sediments were, on average, net precipitating during the day and net dissolving at night throughout the year. Night dissolution rates (−NCCNIGHT) were highest in the austral autumn and lowest in the austral winter driven by changes in respiration (R) and to a lesser extent temperature and Ωarag/pH. Similarly, precipitation during the day (+NCCDAY) was highest in March and lowest in winter, driven primarily by benthic net primary production (NPP) and temperature. On average, sediments were net precipitating over a diel cycle (NCC24h) but shifted to net dissolving in July and December. This shift was largely caused by the differential effects of seasonal cycles in organic metabolism and carbonate chemistry on NCCDAY and NCCNIGHT. The results from this study highlight the large variability in sediment CaCO3 dynamics and the need to include repeated measurements over different months and seasons, particularly in shallow reef systems that can experience large swings in light, temperature, and carbonate chemistry. [ABSTRACT FROM AUTHOR]

Ecosystem functioning is positively linked to biodiversity on land and in the sea. In high‐diversity systems (e.g. coral reefs), species coexist by sharing resources and providing similar functions at different temporal or spatial scales. How species combine to deliver the ecological function they provide is pivotal for maintaining the structure, functioning and resilience of some ecosystems, but the significance of this is rarely examined in low‐diversity systems such as estuaries.We tested whether an ecological function is shaped by biodiversity in a low‐diversity ecosystem by measuring the consumption of carrion by estuarine scavengers. Carrion (e.g. decaying animal flesh) is opportunistically fed on by a large number of species across numerous ecosystems. Estuaries were chosen as the model system because carrion consumption is a pivotal ecological function in coastal seascapes, and estuaries are thought to support diverse scavenger assemblages, which are modified by changes in water quality and the urbanization of estuarine shorelines.We used baited underwater video arrays to record scavengers and measure the rate at which carrion was consumed by fish in 39 estuaries across 1,000 km of coastline in eastern Australia.Carrion consumption was positively correlated with the abundance of only one species, yellowfin bream Acanthopagrus australis, which consumed 58% of all deployed carrion. The consumption of carrion by yellowfin bream was greatest in urban estuaries with moderately hardened shorelines (20%–60%) and relatively large subtidal rock bars (>0.1 km2).Our findings demonstrate that an ecological function can be maintained across estuarine seascapes despite both limited redundancy (i.e. dominated by one species) and complementarity (i.e. there is no spatial context where the function is delivered significantly when yellowfin bream are not present) in the functional traits of animal assemblages. The continued functioning of estuaries, and other low‐diversity ecosystems, might therefore not be tightly linked to biodiversity, and we suggest that the preservation of functionally dominant species that maintain functions in these systems could help to improve conservation outcomes for coastal seascapes. [ABSTRACT FROM AUTHOR]

Corals live in close association with a diverse community of eukaryotes, bacteria, archaea and viruses that, together with the coral host, form the coral holobiont. Fungi are an important component of the coral holobiont; however, knowledge about their taxonomic diversity and the ecological functions these organisms play in reef corals is still scarce. In this study, we used metabarcoding to characterize the fungal community inhabiting the skeleton of eleven coral genera, as well as samples of crustose coralline algae, from Australia and Papua New Guinea. Most of the 24 distinct fungal genera identified were assigned to the phylum Ascomycota, followed by Basidiomycota. Lulworthia and Lulwoana (Ascomycota) were the most abundant and prevalent genera detected in our study. Besides these widely distributed genera, others never associated with corals or marine environments before, such as Geranomyces (Chytriomycota), Flammulina (Basidiomycota) and Ophiosphaerella (Ascomycota), were also detected. The predicted functional groups give insights into potential lifestyles and ecological functions of the fungal community in reef ecosystems. This study provides important observational data on a group of holobiont members that has received little attention. [ABSTRACT FROM AUTHOR]

The jumping spider fauna of 99 Australian islands of coral, volcanic, continental and mixed origin was investigated in terms of taxonomic diversity, origin (source), dispersal and habitat preferences. A total of 110 taxa were recorded; with 18 taxa found on at least five islands. Barrow, Horn, Fitzroy, Fraser, Murray and Moa Islands appeared the most diverse, each with at least 10 species. On all islands combined the most speciose genera were Cytaea (16 species), Cosmophasis (8), 'Lycidas'/Jotus (5), Simaetha (4) and Holoplatys (4). The island faunas appeared to be a less diverse version of the mainland (mostly eastern coast) and showed no evidence of local radiation and endemism. [ABSTRACT FROM AUTHOR]

Coral reefs cover approximately 0.10 to 0.25% of the marine environment and yet are home to around 25% of marine species and support the livelihoods of more than 500 million people. They face a wide range of threats, with the impact of global warming gaining most attention due to its frequently claimed causal link to coral bleaching. Here we review a decade of research into the micrometeorology of Heron Reef, a lagoonal platform coral reef in the southern Great Barrier Reef, Australia. Using novel pontoon‐mounted eddy covariance systems, we show that often >80% of net radiation is partitioned into heating the water overlying the reef, the reef benthos, and substrate. Significant spatial variability in energy and trace gas exchanges occurs over the reef in response to different geomorphic and hydrodynamic conditions. Synoptic weather patterns that bring light winds, clear skies, and high humidity, result in reef scale meteorology that appears to have a greater influence on coral bleaching events than the background oceanic warming trend. The reef develops its own convective internal boundary layer, with potential to influence cloud development and therefore the surface energy balance. Knowledge of such local effects is lacking, so it is recommended that future research is needed into reef scale processes and how they interact with larger‐scale forcing. Key Points: A decade of research on the meteorology of Heron Reef in the Great Barrier Reef, Australia, is reviewedEnergy flux and trace gas exchange with the atmosphere over Heron Reef under a range of conditions including coral bleaching are summarizedSuggestions are made for future research to advance understanding of coral reef – atmosphere interactions [ABSTRACT FROM AUTHOR]

Spiders of the genus Desis Walckenaer, 1837 (Araneae: Desidae) are water-adapted spiders and live in the intertidal zone on reefs, marine debris and under rocks. Here, we describe a new intertidal species from tropical Queensland and name it after Bob Marley, whose song "High Tide or Low Tide" inspired us as it lives in a "high tide low tide" habitat. We also re-describe a close morphological relative, Desis vorax L. Koch, 1872 from Sāmoa. This species was described some 150 years ago from the Godeffroy Collection which holds the oldest major collection of Australasian and Pacific spiders, now mainly hosted in the Centre of Natural History in Hamburg (CeNak). A third species, Desis hartmeyeri Simon, 1909, was described from juvenile specimens only and is considered a nomen dubium. "None but ourselves can free our minds." Bob Marley, Redemption Song (1980). [ABSTRACT FROM AUTHOR]

This study uses information derived from cores to describe the Holocene accretion history of coral reefs in the macrotidal (up to 11 m tidal range) Buccaneer Archipelago of the southern Kimberley coast, Western Australia. The internal architecture of all cored reefs is broadly similar, constituting well-preserved detrital coral fragments, predominantly branching Acropora, in a poorly sorted sandy mud matrix. However, once the reefs reach sea level, they diverge into two types: low intertidal reefs that maintain their detrital character and develop relatively narrow, horizontal or gently sloping reef flats at approximately mean low water spring, and high intertidal reefs that develop broad coralline algal-dominated reef flats at elevations between mean low water neap and mean high water neap. The high intertidal reefs develop where strong, ebb-dominated, tidal asymmetry retains seawater over the low tide and allows continued accretion. Both reef types are ultimately constrained by sea level but differ in elevation by 3-4 m. [ABSTRACT FROM AUTHOR]

Studies on the population and community dynamics of scleractinian corals typically focus on catastrophic mortality associated with acute disturbances (e.g., coral bleaching and outbreaks of crown-of-thorns starfish), though corals are subject to high levels of background mortality and injuries caused by routine and chronic processes. This study quantified prevalence (proportion of colonies with injuries) and severity (areal extent of injuries on individual colonies) of background mortality and injuries for four common coral taxa (massive Porites, encrusting Montipora, Acropora hyacinthus and branching Pocillopora) on the Great Barrier Reef, Australia. Sampling was conducted over three consecutive years during which there were no major acute disturbances. A total of 2276 adult colonies were surveyed across 27 sites, within nine reefs and three distinct latitudinal sectors. The prevalence of injuries was very high (>83%) across all four taxa, but highest for Porites (91%) and Montipora (85%). For these taxa ( Montipora and Pocillopora), there was also significant temporal and spatial variation in prevalence of partial mortality. The severity of injuries ranged from 3% to more than 80% and varied among coral taxa, but was fairly constant spatially and temporally. This shows that some injuries have considerable longevity and that corals may invest relatively little in regenerating tissue over sites of previous injuries. Inter-colony variation in the severity of injury also had no apparent effect on the realized growth of individual colonies, suggesting that energy diverted to regeneration has a limited bearing on overall energetic allocation, or impacts on other life-history processes (e.g., reproduction) rather than growth. Establishing background levels of injury and regeneration is important for understanding energy investment and life-history consequences for reef-building corals as well as for predicting susceptibility to, and capacity to recover from, acute disturbances. [ABSTRACT FROM AUTHOR]

Changing oceanic conditions, particularly ocean warming and altered currents, can affect the reproductive success of corals. Improving the knowledge of coral reproductive processes at the marginal range limits of coral reefs is important for understanding the ecology of subtropical coral communities and the potential for coral species to expand their ranges in higher latitudes in the future. The extent of live coral cover around subtropical Lord Howe Island (LHI; 31°33′S, 159°05′E) approximately 600 km off the east coast of Australia, has been relatively stable over the last several decades; however, shifts in dominant species in the adult coral community have been reported. To examine the potential influences of recent altered currents and shifts in dominant scleractinian taxa within this community, this study examined spatial and seasonal variation of coral larval settlement at different habitats within the LHI reef lagoon. The study also assessed whether the assemblage of scleractinian corals settling at LHI has changed between 1990-1991 and 2011-2012. Mean densities of coral settlement in 2011-2012 (230 spat m yr) were consistent with those reported in 1990-1991 and in other regions. However, changes in taxonomic composition were apparent with increases in the proportion of Acroporidae spat at some sites. Settlement of all taxa was highest over summer months, whereas during winter only one coral spat (Pocilloporidae) was detected. Coral settlement was highest and most taxonomically diverse at sites closest to the reef crest, where mortality of settled spat was also greatest. Rates of settlement were high compared with juvenile densities; hence, post-settlement mortality is also likely to be high. Post-settlement processes, influenced by local environmental conditions, are likely to be very important in structuring the adult coral communities within the LHI reef lagoon. [ABSTRACT FROM AUTHOR]

Marine reserve networks must ensure the representation of important conservation features, and also guarantee the persistence of key populations. For many species, designing reserve networks is complicated by the absence or limited availability of spatial and life-history data. This is particularly true for data on larval dispersal, which has only recently become available. However, systematic conservation planning methods currently incorporate demographic processes through unsatisfactory surrogates. There are therefore two key challenges to designing marine reserve networks that achieve feature representation and demographic persistence constraints. First, constructing a method that efficiently incorporates persistence as well as complementary feature representation. Second, incorporating persistence using a mechanistic description of population viability, rather than a proxy such as size or distance. Here we construct a novel systematic conservation planning method that addresses both challenges, and parameterise it to design a hypothetical marine reserve network for fringing coral reefs in the Keppel Islands, Great Barrier Reef, Australia. For this application, we describe how demographic persistence goals can be constructed for an important reef fish species in the region, the bar-cheeked trout (Plectropomus maculatus). We compare reserve networks that are optimally designed for either feature representation or demographic persistence, with a reserve network that achieves both goals simultaneously. As well as being practically applicable, our analyses also provide general insights into marine reserve planning for both representation and demographic persistence. First, persistence constraints for dispersive organisms are likely to be much harder to achieve than representation targets, due to their greater complexity. Second, persistence and representation constraints pull the reserve network design process in divergent directions, making it difficult to efficiently achieve both constraints. Although our method can be readily applied to the data-rich Keppel Islands case study, we finally consider the factors that limit the method’s utility in information-poor contexts common in marine conservation. [ABSTRACT FROM AUTHOR]

Two new species of the water mite family Pontarachnidae are described from Queensland, Australia: Pontarachna curvipalpis and Litarachna haleioides. Pontarachna curvipalpis can be distinguished from other members of the genus by its stocky leg segments, long apodemes of the fourth coxae, strongly bowed pre- and postgenital sclerite and wheel-like acetabula without radiating spokes. Litarachna haleoides is characterized by strongly bowed but not touching genital sclerites, relatively short apodemes of the fourth coxae, a slender palp and P2 with a ventral projection. A short discussion is provided on the occurrence of water mites on the Great Barrier Reef. [ABSTRACT FROM AUTHOR]