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Anthropogenic climate change has caused widespread loss of species biodiversity and ecosystem productivity across the globe, particularly on tropical coral reefs. Predicting the future vulnerability of reef-building corals, the foundation species of coral reef ecosystems, is crucial for cost-effective conservation planning in the Anthropocene. In this study, we combine regional population genetic connectivity and seascape analyses to explore patterns of genetic offset (the mismatch of gene–environmental associations under future climate conditions) in Acropora digitifera across 12 degrees of latitude in Western Australia. Our data revealed a pattern of restricted gene flow and limited genetic connectivity among geographically distant reef systems. Environmental association analyses identified a suite of loci strongly associated with the regional temperature variation. These loci helped forecast future genetic offset in gradient forest and generalized dissimilarity models. These analyses predicted pronounced differences in the response of different reef systems in Western Australia to rising temperatures. Under the most optimistic future warming scenario (RCP 2.6), we predicted a general pattern of increasing genetic offset with latitude. Under the extreme climate scenario (RCP 8.5 in 2090–2100), coral populations at the Ningaloo World Heritage Area were predicted to experience a higher mismatch between current allele frequencies and those required to cope with local environmental change, compared to populations in the inshore Kimberley region. The study suggests complex and spatially heterogeneous patterns of climate-change vulnerability in coral populations across Western Australia, reinforcing the notion that regionally tailored conservation efforts will be most effective at managing coral reef resilience into the future.

Modern systematics integrating molecular and morphological data has greatly improved our understanding of coral evolutionary relationships during the last two decades and led to a deeply revised taxonomy of the order Scleractinia. The family Merulinidae (Cnidaria: Scleractinia) was recently subjected to a series of revisions following this integrated approach but the phylogenetic affinities of several genera ascribed to it remain unknown. Here, we partially fill this gap through the study of 89 specimens belonging to all 10 valid species from four genera (Caulastraea, Erythrastrea, Oulophyllia and Dipsastraea) collected from 14 localities across the Indo‐Pacific realm. Four molecular loci (histone H3, COI, ITS and IGR) were sequenced, and a total of 44 skeletal morphological characters (macromorphology, micromorphology and microstructure) were analysed. Molecular phylogenetic analyses revealed that the phaceloid Caulastraea species are split into two distinct lineages. A species previously ascribed to the genus Dipsastraea, Dipsastraea maxima, is also recovered in one on these lineages. Furthermore, Erythrastrea is nested within Oulophyllia. The molecular reconstructions of evolutionary relationships are further corroborated by multiscale morphological evidence. To resolve the taxonomy of these genera, Astraeosmilia is resurrected to accommodate Astraeosmilia connata, Astraeosmilia curvata, Astraeosmilia tumida and Astraeosmilia maxima, with Caulastraea retaining Caulastraea furcata and Caulastraea echinulata. Based on the examination of type material, Erythrastrea flabellata is considered an objective synonym of Lobophyllia wellsi, which is transferred to Oulophyllia following the obtained morpho‐molecular results. This work further confirms that an integrated morpho‐molecular approach based on a rigorous phylogenetic framework is fundamental for an objective classification that reflects the evolutionary history of scleractinian corals.

Aim: Environmental DNA (eDNA) metabarcoding has demonstrated its applicability as a highly sensitive biomonitoring tool across small spatial and temporal scales in marine ecosystems. However, it has rarely been tested across large spatial scales or biogeographical barriers. Here, we scale up marine eDNA metabarcoding, test its ability to detect a major marine biogeographic break and evaluate its use as a regional biomonitoring tool in Australia. Location: North-western Australia (NWA). Methods: We applied metabarcoding assays targeting the mitochondrial 16S rRNA and CO1 genes to 284 surface seawater eDNA samples collected from 71 mid-shelf, inshore, coastal and nearshore estuarine sites over 700 km of the NWA coastline. Results: Metabarcoding detected a wide range of bony fish (404 taxa), elasmobranchs (44) and aquatic reptiles (5). We detected bioregional and depth differentiation within inshore bony fish communities. These findings support the presence of a marine biogeographic break, which is purported to occur in the vicinity of Cape Leveque, demarcating the border between the Kimberley and Canning bioregions. Inshore bony fish and elasmobranch communities, as well as coastal bony fish assemblages, were additionally found to differ between the South and North Kimberley regions suggesting previously unrecognized subregional differentiation amongst these taxa. The overall compositional data have been used to update distribution information for a number of endangered, elusive and data-deficient taxa, including sawfish (family: Pristidae), northern river shark (Glyphis garricki) and wedgefish (genus: Rhynchobatus). Main conclusions: eDNA metabarcoding demonstrated a high level of sensitivity that was able to discern fine-scale patterns across the large-scale, remote and oceanographically complex region of North-western Australia. Importantly, this study highlights the potential of integrating broad-scale eDNA metabarcoding alongside other baseline surveys and long-t

Aim: Forecasting the influence of climate change on coral biodiversity and reef functioning is important for informing policy decisions. Dominance shifts, tropicalization and local extinctions are common responses of climate change, but uncertainty surrounds the reliability of predicted coral community transformations. Here, we use species distribution models (SDMs) to assess changes in suitable coral habitat and associated patterns in biodiversity across Western Australia (WA) under present-day and future climate scenarios (RCP 2.6 and RCP 8.5). Location: Coral reef systems and communities in WA. Methods: We developed SDMs with model prediction uncertainty analyses, using specimen-based occurrence records of 188 hermatypic scleractinian coral species and seven variables to estimate present-day and future changes to coral species distribution and biodiversity patterns in WA under climate change conditions. Results: We found that suitable habitat is predicted to increase across all regions in WA under (Formula presented.), (Formula presented.) and (Formula presented.) scenarios with all tropical and subtropical regions remaining coral biodiversity strongholds. Under the extreme (Formula presented.) scenario, however, a clear tropicalization trend could be observed with coral species expanding their range to mid-high latitude regions, while a substantial drop in coral species richness was predicted at low latitude tropical coral reefs, such as the inshore Kimberley and offshore NW reefs. Despite the predicted expansion south, we identified a net decline in coral biodiversity across the WA coastline. Main conclusions: Results from the models predicted higher net coral biodiversity loss at low latitude tropical regions compared with net gains at mid-high latitude regions under (Formula presented.). These results are likely to be representative of latitudinal trends across the Southern Hemisphere and highlight that increases in habitat suitability at higher latitudes may

Environmental DNA (eDNA) metabarcoding, a technique for retrieving multispecies DNA from environmental samples, can detect a diverse array of marine species from filtered seawater samples. There is a growing potential to integrate eDNA alongside existing monitoring methods in order to establish or improve the assessment of species diversity. Remote island reefs are increasingly vulnerable to climate-related threats and as such there is a pressing need for cost-effective whole-ecosystem surveying to baseline biodiversity, study assemblage changes and ultimately develop sustainable management plans. We investigated the utility of eDNA metabarcoding as a high-resolution, multitrophic biomonitoring tool at the Cocos (Keeling) Islands, Australia (CKI)—a remote tropical coral reef atoll situated within the eastern Indian Ocean. Metabarcoding assays targeting the mitochondrial 16S rRNA and CO1 genes, as well as the 18S rRNA nuclear gene, were applied to 252 surface seawater samples collected from 42 sites within a 140 km2 area. Our assays successfully detected a wide range of bony fish and elasmobranchs (244 taxa), crustaceans (88), molluscs (37) and echinoderms (7). Assemblage composition varied significantly between sites, reflecting habitat partitioning across the island ecosystem and demonstrating the localisation of eDNA signals, despite extensive tidal and oceanic movements. In addition, we document putative new occurrence records for 46 taxa and compare the efficiency of our eDNA approach to visual survey techniques at CKI. Our study demonstrates the utility of a multimarker metabarcoding approach in capturing multitrophic biodiversity across an entire coral reef atoll and sets an important baseline for ongoing monitoring and management.

Management strategies designed to conserve coral reefs threatened by climate change need to incorporate knowledge of the spatial distribution of inter- and intra-specific genetic diversity. We characterized patterns of genetic diversity and connectivity using single nucleotide polymorphisms (SNPs) in two reef-building corals to explore the eco-evolutionary processes that sustain populations in north-west Australia. Our sampling focused on the unique reefs of the Kimberley; we collected the broadcast spawning coral Acropora aspera (n = 534) and the brooding coral Isopora brueggemanni (n = 612) across inter-archipelago (tens to hundreds of kilometres), inter-reef (kilometres to tens of kilometres) and within-reef (tens of metres to a few kilometres) scales. Initial analysis of A. aspera identified four highly divergent lineages that were co-occurring but morphologically similar. Subsequent population analyses focused on the most abundant and widespread lineage, Acropora asp-c. Although the overall level of geographic subdivision was greater in the brooder than in the spawner, fundamental similarities in patterns of genetic structure were evident. Most notably, limits to gene flow were observed at scales '35 kilometres. Further, we observed four discrete clusters and a semi-permeable barrier to dispersal that were geographically consistent between species. Finally, sites experiencing bigger tides were more connected to the metapopulation and had greater gene diversity than those experiencing smaller tides. Our data indicate that the inshore reefs of the Kimberley are genetically isolated from neighbouring oceanic bioregions, but occasional dispersal between inshore archipelagos is important for the redistribution of evolutionarily important genetic diversity. Additionally, these results suggest that networks of marine reserves that effectively protect reefs from local pressures should be spaced within a few tens of kilometres to conserve the existing patterns of demogr

OBJECTIVE: To examine Corporate Social Responsibility (CSR) tactics by identifying the key characteristics of CSR strategies as described in the corporate documents of selected 'Big Food' companies. METHODS: A mixed methods content analysis was used to analyse the information contained on Australian Big Food company websites. Data sources included company CSR reports and web-based content that related to CSR initiatives employed in Australia. RESULTS: A total of 256 CSR activities were identified across six organisations. Of these, the majority related to the categories of environment (30.5%), responsibility to consumers (25.0%) or community (19.5%). CONCLUSIONS: Big Food companies appear to be using CSR activities to: 1) build brand image through initiatives associated with the environment and responsibility to consumers; 2) target parents and children through community activities; and 3) align themselves with respected organisations and events in an effort to transfer their positive image attributes to their own brands. IMPLICATIONS: Results highlight the type of CSR strategies Big Food companies are employing. These findings serve as a guide to mapping and monitoring CSR as a specific form of marketing.