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Aim: Understanding the formation and maintenance of biogeographical breaks is fundamental for developing analyses related to biodiversity and conservation. Biogeographical patterns along China's coast are changing dramatically in the face of climate change and alterations in land‐use. In this paper, we sought to clarify the mechanisms responsible for the formation and maintenance of a biogeographical barrier on China's coast. Location: Coastline of northern China. Methods: We have reviewed literature of research related to biogeographical and phylogeographical patterns of intertidal macrobenthos along the coast of Jiangsu Province and adjacent areas, summarized the distribution patterns and biogeographical breakers. We have also reviewed literature about the processes and drivers on coastal biogeographical breaks, to clarify the mechanisms acting to the northward shift of the biogeographical break. Results: The Yangtze (Changjiang) River Estuary Biogeographical Barrier (YREBB) at 30°–31°N, which serves as a coastal biogeographical boundary for the Cold Temperate Northwest Pacific Province and the Warm Temperate Northwest Pacific Province for marine species, has moved northward to ~33°–34°N due to the changes in habitat continuity, oceanographic circulation and climate factors. Consequently, a new biogeographic barrier for intertidal macrobenthos, the Subei Biogeographical Barrier (SBB) on the central coast of Jiangsu Province, has emerged. Main conclusions: The formation and maintenance of the SBB are closely related to the larval dispersal potential, larval settlement success and post‐settlement population establishment, all of which have been profoundly influenced by anthropogenic environmental changes. The northward shift of the YREBB and the appearance of the SBB provide an excellent model system for investigating the impacts of climate change and land‐use change on coastal biogeographic patterning and for clarifying the mechanisms underlying the formation and maintenance of biogeographical barriers in the face of the unprecedented environmental changes. [ABSTRACT FROM AUTHOR]

Biodiversity and distributions Six papers in this issue are focused on the biodiversity assessment and conservation management. Knowledge of species distribution across space and time is critical to ecological conservation and environmental management at the local, regional and global scales (Albert et al., 2021). Reliable DNA barcode reference libraries are critical for accurate species identification and biodiversity monitoring based on eDNA. Therefore, by no means will this special issue provide a full picture of environmental DNA (eDNA)-based studies; rather, it can serve as a window to showcase the recent and global developments in environmental DNA-based biodiversity assessment and conservation management. [Extracted from the article]

Geodiversity—the diversity of abiotic features and processes of the Earth's surface and subsurface—is an increasingly used concept in ecological research. A growing body of scientific literature has provided evidence of positive links between geodiversity and biodiversity. These studies highlight the potential of geodiversity to improve our understanding of biodiversity patterns and to complement current biodiversity conservation practices and strategies. However, definitions of geodiversity in ecological research vary widely. This can hinder the progress of geodiversity–biodiversity research and make it difficult to synthesize findings across studies. We therefore call for greater awareness of how geodiversity is currently defined and for more consistent use of the term 'geodiversity' in biodiversity research. [ABSTRACT FROM AUTHOR]

Aim: Patterns of benthic biodiversity at the macroecological scale remain poorly characterised throughout the Chilean latitudinal gradient, in part due to the lack of integrated databases, uneven sampling effort, and the use of species richness alone to quantify biodiversity. Different diversity measures, encompassing taxonomic and functional components, may give us extra information on biodiversity relevant to conservation planning and management. Thus, evaluating the spatial complementarity of these measures is essential. Location: Coast and continental shelf of Chile. Methods: The latitudinal gradient of Chile was divided into five ecoregions according to the Marine Ecosystems of the World classification. Using a 55 × 55 km equal area grid, we estimated the incidence coverage‐based estimator (ICE), taxonomic distinctness (Δ+) and three measures of functional diversity: functional richness (FRic), functional evenness (FEve) and functional divergence (FDiv). For each measure, we described spatial patterns, identified hotspots, evaluated hotspot congruence and evaluated complementarity between measures. Results: Diversity patterns varied between ecoregions and over the latitudinal gradient. ICE and Δ+ peaked in the Chiloense and Channels and Fjords ecoregions. Δ+ and FRic present a similar pattern at mid‐latitudes. FEve showed a contrary pattern, principally with FRic. Areas with high numbers of hotspots differed spatially according to each metric, and three latitudinal bands were observed. ICE, Δ+ and FRic were positively correlated, but the hotspot overlap at the grid cell level was more limited. Main Conclusions: The complementarity between taxonomic and functional diversity measures is limited when we observe the overlap between grid cells representing hotspots. However, some regions are consistently identified as highly diverse, with the Magellanic Province (Chiloense and Channels and Fjords ecoregions) being the most important for the richness, taxonomic and functional diversity of benthos. Confirmation of the importance of this region can help prioritise conservation efforts. [ABSTRACT FROM AUTHOR]

Aim: Rare species make substantial contributions to coastal ecosystem functions. Functional rarity (FR) and phylogenetic rarity (PR) are important features for biodiversity conservation. This work aimed to discuss the necessity and reasonableness of conserving fish FR and PR in coastal seas. Location: China. Methods: By compiling historical fish investigation data, joint species distribution modelling (JSDM) was applied to model fish communities in coastal China Seas. Biogeographic patterns of FR and PR were explored, and the effectiveness of current MPA networks in terms of match/mismatch with the hotspots of rarity was assessed. Results: A total of 44 functionally rare species and 22 phylogenetically rare species were identified. Six of these species were both functionally and phylogenetically rare, and only one was listed as endangered on the Red List of the International Union for Conservation of Nature (IUCN). Functional rarity hotspots covered 10.27% of the coastal areas, which geographically converged in the southern and eastern coast of Taiwan, the Yangtze River Estuary and the Yellow River Estuary. Phylogenetic rarity hotspots only covered 3.06% of the coastal areas, which were sporadically distributed in the coastal East China Sea, the Bohai Sea and the northern Yellow Sea. Current marine‐protected areas (MPAs) only represented 16.16% of the FR hotspots and 20.48% of the PR hotspots, indicating substantial mismatched areas between the MPAs and the hotspots of FR and PR. Main Conclusions: Only considering threatened species in conservation practices will omit functionally and phylogenetically rare species because FR and PR are not necessarily correlated with species threat status on the IUCN Red List. Functional rarity hotspots do not necessarily overlap with PR hotspots, and current MPAs mismatch the majority of these areas. We therefore advocate that conservation prioritization and expansion of MPA networks should account for FR and PR both at the species and site levels. [ABSTRACT FROM AUTHOR]

Conservation policies and environmental impact assessments commonly target threatened species and habitats. Nevertheless, macroecological research provides reasons why also common species should be considered. We investigate the consequences of focussing solely on legally protected species and habitats in a spatial conservation planning context using a comprehensive, benthic marine data set from the northern Baltic Sea. Using spatial prioritization and surrogacy analysis, we show that the common approach in conservation planning, where legally listed threatened species and habitats are the focus of conservation efforts, could lead to poor outcomes for common species (and therefore biodiversity as a whole), allowing them to decline in the future. If conservation efforts were aimed solely at threatened species, common species would experience a loss of 62% coverage. In contrast, if conservation plans were based only on common species, threatened species would suffer a loss of 1%. Threatened species are rare and their ecological niches distinct, making them poor surrogates for biodiversity. The best results are achieved by unified planning for all species and habitats. The minimal step towards acknowledging common species in conservation planning would be the inclusion of the richness of common species, complemented by information on indicator species or species of high importance for ecosystem functioning. The trade‐off between planning for rare and common species should be evaluated, to minimize losses to biodiversity. [ABSTRACT FROM AUTHOR]

Aim: (i) To determine whether area and connectivity of temporary ponds can predict plant species diversity, and the diversity and abundance of different plant life histories; (ii) To explore whether pond connectivity with the river prior to river regulation predicts better plant diversity patterns than current pond connectivity, suggestive of possible effects of connectivity loss. Location: Eastern Carpathian Mountains, Romania, Europe. Methods: We fitted linear and generalized linear models (LM and GLM) to examine whether pond area and current distance from the Olt River predict plant species richness, Shannon diversity and relative cover of different social behaviour types and overall plant species richness and Shannon diversity. Using historical maps, we measured pond distance from the river ca. 60 years before the Olt River was regulated, and we refitted the LM and GLM models using pond area and past distance from the river as independent variables. Results: Total plant species richness increased with pond area, and it decreased with the distance from the river, but total plant Shannon diversity index was affected, positively, only by pond area. The strength of responses to pond area and connectivity of species richness, Shannon diversity and relative cover varied across the different social behaviour types. Past and current distances between ponds and riverbeds had similar effects on plant diversity, with some evidence for stronger effect of the present connectivity on specialist species Shannon diversity and a weaker effect on disturbance tolerants, generalists and competitors. Main Conclusions: Pond area and connectivity with the landscape are important predictors of the diversity of plant life history strategies, and therefore, useful tools in pond conservation. Consistent species richness and Shannon diversity responses of wetland specialists to pond area and connectivity make this life history type well suited for monitoring pond condition. [ABSTRACT FROM AUTHOR]

Aim: Biodiversity hotspots often span international borders, thus conservation efforts must as well. China is one of the most biodiverse countries and the length of its international land borders is the longest in the world; thus, there is a strong need for transboundary conservation. We identify China's transboundary conservation hotspots and analyse the potential effects of the Belt and Road Initiative (BRI) on them to provide recommendations for conservation actions. Location: China, Asia. Methods: We compiled a species list of terrestrial vertebrates that span China's borders. Using their distribution, we extracted the top 30% of the area with the highest richness value weighted by Red List category and considered these transboundary hotspots for conservation priority. Then we analysed protected area (PA) coverage and connectivity to identify conservation gaps. To measure potential impact of the BRI, we counted the species whose distribution range is traversed by the BRI, and calculated the aggregation index, proportion of natural land and night light index along its routes. Results: We identified 1964 terrestrial vertebrate species living in the border region. We identified four transboundary hotspots and found insufficient PA coverage and low connectivity in three of them. The BRI routes intersected all four hotspots and traversed 82.4% (1619/1964) of the transboundary species, half of which (918) are sensitive to the potential risks brought by the BRI. Night light index increased generally along the BRI. However, the proportion of natural land and the aggregation index near the BRI showed different trends in hotspots. Main Conclusions: There is an urgent need for conservation action in China's transboundary region. The BRI should put biodiversity conservation at the core of its development strategy. Furthermore, we suggest using the planned BRI as a platform for dialogue and consultation, knowledge and data sharing, and joint planning to promote transboundary conservation. [ABSTRACT FROM AUTHOR]

Aim: The Irano‐Anatolian biodiversity hotspot is among the least‐known biodiversity hotspots on earth. In this study, we aim to map the richness and genetic divergence of lizards in the biodiversity hotspot and its surrounding areas and identify the most important determinants of the richness and genetic divergence patterns. Location: Iran and Turkey (Irano‐Anatolian biodiversity hotspot). Methods: Here, we mapped the distribution of 211 lizard species in Iran and Turkey using existing occurrence data and generated the first genetic divergence pattern map of the lizard species in the two countries to identify areas of high species diversity and genetic divergence in the Irano‐Anatolian biodiversity hotspot. We also identified determinants of lizard richness and genetic divergence patterns. Results: Results showed that the Zagros Mountains, Central Iranian Plateau and the northern Persian Gulf have the highest lizard richness. The Zagros Mountains, Central Iranian Plateau, the northern Persian Gulf and the regions around the Lut Desert and Jazmourian Plain have the highest total genetic divergence in Iran. Alborz and Kopet Dag mountains and south western parts of Turkey have the highest average genetic divergence. The annual temperature was the most important predictor of lizard richness, and temperature change velocity was the most influential determinant of genetic divergence pattern. Much to our surprise, species diversity and most areas with high genetic divergence are located outside of Irano‐Anatolian biodiversity hotspot. Main conclusions: This study showed that lizard richness and genetic divergence patterns are associated with current and past climate. In particular, this study highlights the legacy of past climate changes on lizard genetic divergence distribution patterns. We showed that most of the species‐rich and genetically diverse regions are located outside of the biodiversity hotspot. So conservation efforts that are concentrated inside the biodiversity hotspot may not benefit lizard biodiversity conservation. Thus, future studies and conservation programs on the biodiversity hotspot should also consider its surrounding areas. [ABSTRACT FROM AUTHOR]

Aim: Groundwater harbours an exceptional fauna and provides invaluable ecosystem services, yet is among the least explored and consequently least protected ecosystems. Successful protection of its biodiversity depends on complete species inventories, knowledge of species spatial distribution, and quantification of biodiversity patterns, as well as disentanglement of the processes that shaped biodiversity patterns. We studied the hyper‐speciose amphipod genus Niphargus as a model system within a global subterranean biodiversity hotspot. We linked the biodiversity patterns with possible underlying processes and discuss the needs to include information on different origins of biodiversity into conservation approaches. Location: Europe, Western Balkans. Methods: We analysed biodiversity patterns of Niphargus using two biodiversity metrics, species richness and phylogenetic diversity, on a grid‐based approach. To account for high cryptic diversity, we replaced nominal species with taxonomic units identified in unilocus delimitations (MOTUs). We built a time‐calibrated multilocus phylogeny of 512 Niphargus MOTUs from within and outside the study area, and calculated Faith's phylogenetic diversity, standardized effect sizes of phylogenetic diversity, and residual of phylogenetic diversity regressed onto species richness. Results: Within the study area, we recognized 245 MOTUs, belonging to different Niphargus clades. Species richness is highest in a north‐western hotspot, although some species‐rich cells were detected also in the south‐east. High phylogenetic diversity coincides with high species richness in the north‐west, while in the south‐east it is lower than expected. Main conclusions: We have shown that species richness does not predictably correlate with phylogenetic diversity. This difference suggests that different processes have led to the formation of species‐rich areas in the Western Balkans: through a combination of dispersal and speciation in the north‐west, and local radiation in the south‐east, respectively. This calls for caution in conservation strategies relying solely on number of species and may change the view on conservation priorities within this region. [ABSTRACT FROM AUTHOR]

Aim: Locally abundant species are typically widespread, while locally scarce species are geographically restricted—the so‐called abundance‐occupancy relationships (AORs). AORs help explain the drivers of species rarity and community assembly, but little is known about how variation around such relationship is driven by species traits and niche‐based processes, particularly in tropical woody plants. We tested the hypothesis that AORs in tropical dryland woody plants are positive and mediated by niche and functional traits along environmental gradients. Location: The Caatinga dry forest and Cerrado savannah, Brazil. Methods: We aggregated abundance and occurrence data into grid‐cells representing local (10‐km) to landscape scales (50‐km). We calculated species mean relative abundance at occupied grid‐cells (local abundance) and the proportion of grid‐cells occupied (occupancy), and estimated their niche breadth and marginality along multivariate environmental gradients. Results: AORs were positive but weak at different scales in both regions due to some locally abundant but geographically restricted species, with most species being both locally and geographically rare. Cross‐species variation in local abundance was largely unpredictable, but occupancy was strongly driven by niche and functional traits, with a prominent negative effect of niche marginality. Geographically restricted species were associated with rare habitats, such as wetter and less intensively used habitats. Large seeds and abiotic dispersal favoured occupancy in Caatinga at small and large spatial scales, respectively, whereas species with conservative leaves were more widespread across scales in Cerrado. Main conclusions: Woody plants in dry tropical biotas exhibit weak AORs, a pattern likely related to low habitat availability and dispersal limitation. Caatinga and Cerrado biotas emerge as environmentally structured at multiple spatial scales, with several habitat‐specialist rare species bearing specific regenerative and resource‐use traits and relying on conditions threatened by climate change and land‐use intensification. Examining AORs through the lens of niche, functional traits and spatial scales enables mapping patterns and drivers of species commonness and rarity, enhancing understanding of species assembly and providing tools for biodiversity conservation. [ABSTRACT FROM AUTHOR]

Aim: The Appalachian forests ecoregion in eastern North America supports a diverse and highly endemic temperate biota, which is potentially threatened by rapid climate change. We investigated possible outlooks for biodiversity in this biologically important ecoregion under future climate change. Location: Appalachian forests ecoregion, USA. Methods: We estimated distributional shifts for 258 forest‐dependent vertebrates of conservation concern in four major taxonomic groups (amphibians, birds, mammals and reptiles) under short‐ (2040) and long‐term (2080s) climate change using ecological niche modelling. We examined which groups are likely most vulnerable to climate change and identified places predicted to experience the greatest changes in their species assemblages and those predicted to support high species richness under various future scenarios. To assess species' vulnerability, we compared and regressed future projected range against present range estimates for each species. To evaluate which places could see greatest changes, we mapped species richness and turnover in each taxonomic group. Results: A total of 30%–33% and 31%–38% of species were predicted to lose > 50% of area that is currently climatically suitable under short‐ and long‐term climate change, respectively. We expect climate change to impact amphibians and mammals more than birds and reptiles: a much larger fraction of amphibian and mammal (22%–48% in 2040; 29%–56% in 2080s) species were predicted to lose more than half of their present climatically suitable habitat area compared with birds and reptiles (1%–12% in 2040; 6%–12% in 2080s). While species were predicted to move northward and upslope assuming full dispersal, the Blue Ridge, Cumberland Plateau and southern Central Appalachians subregions are poised to remain as richness hotspots under the broad range of scenarios explored in this study. Main conclusions: Our results highlighted species groups and locations that policymakers and conservation practitioners should emphasize in planning vertebrate conservation efforts in the Appalachians under future climate scenarios. [ABSTRACT FROM AUTHOR]

Aim: Natural disaster risk reduction (DRR) is becoming a more important function of protected area (PAs) for current and future global warming. However, biodiversity conservation and DRR have been handled separately and their interrelationship has not been explicitly addressed. This is mainly because, due of prevailing strategies and criteria for PA placement, a large proportion of PAs are currently located far from human‐occupied areas, and habitats in human‐occupied areas have been largely ignored as potential sites for conservation despite their high biodiversity. If intensely developed lowland areas with high flooding risk overlap with important sites for biodiversity conservation, it would be reasonable to try to harmonize biodiversity conservation and human development in human‐inhabited lowland areas. Here, we examined whether extant PAs can conserve macroinvertebrate and freshwater fish biodiversity and whether human‐inhabited lowland flood risk management sites might be suitable to designate as freshwater protected areas (FPAs). Location: Across Japan. Methods: We examined whether extant PAs can conserve macroinvertebrate and freshwater fish biodiversity and analysed the relationship between candidate sites for new FPAs and flood disaster risk and land use intensity at a national scale across Japan based on distribution data for 131 freshwater fish species and 1395 macroinvertebrate species. Results: We found that extant PAs overlapped with approximately 30% of conservation‐priority grid cells (1 km2) for both taxa. Particularly for red‐listed species, only one species of freshwater fish and three species of macroinvertebrate achieved the representation target within extant PAs. Moreover, more than 40% of candidate conservation‐priority grid cells were located in flood risk and human‐occupied areas for both taxa. Main conclusions: Floodplain conservation provides suitable habitat for many freshwater organisms and helps control floodwaters, so establishing new FPAs in areas with high flood risk could be a win‐win strategy for conserving freshwater biodiversity and enhancing ecosystem‐based DRR (eco‐DRR). [ABSTRACT FROM AUTHOR]

Aim: Introduced predators negatively impact biodiversity globally, with insular fauna often most severely affected. Here, we assess spatial variation in the number of terrestrial vertebrates (excluding amphibians) killed by two mammalian mesopredators introduced to Australia, the red fox (Vulpes vulpes) and feral cat (Felis catus). We aim to identify prey groups that suffer especially high rates of predation, and regions where losses to foxes and/or cats are most substantial. Location: Australia. Methods: We draw information on the spatial variation in tallies of reptiles, birds and mammals killed by cats in Australia from published studies. We derive tallies for fox predation by (i) modelling continental‐scale spatial variation in fox density, (ii) modelling spatial variation in the frequency of occurrence of prey groups in fox diet, (iii) analysing the number of prey individuals within dietary samples and (iv) discounting animals taken as carrion. We derive point estimates of the numbers of individuals killed annually by foxes and by cats and map spatial variation in these tallies. Results: Foxes kill more reptiles, birds and mammals (peaking at 1071 km−2 year−1) than cats (55 km−2 year−1) across most of the unmodified temperate and forested areas of mainland Australia, reflecting the generally higher density of foxes than cats in these environments. However, across most of the continent – mainly the arid central and tropical northern regions (and on most Australian islands) – cats kill more animals than foxes. We estimate that foxes and cats together kill 697 million reptiles annually in Australia, 510 million birds and 1435 million mammals. Main conclusions: This continental‐scale analysis demonstrates that predation by two introduced species takes a substantial and ongoing toll on Australian reptiles, birds and mammals. Continuing population declines and potential extinctions of some of these species threatens to further compound Australia's poor contemporary conservation record. [ABSTRACT FROM AUTHOR]

Aim: Biodiversity conservation relies in part on enduring habitat in protected areas. In fire‐prone ecosystems, shifts in species' ranges will result both from changes in climate and fire‐catalysed vegetation change, which could lead to niche contraction and undermine protected‐area efficacy. We explored these dynamics for three forest species with varied niches representative of other taxa and different hypothesized responses to fire‐regime change (black‐backed woodpecker, Picoides arcticus; North American marten, Martes spp.; and red squirrel, Tamiasciurus hudsonicus). We asked: How do the extent and spatial pattern of these species' distributions change during the 21st century based on the independent and joint effects of climate and vegetation? Location: Greater Yellowstone Ecosystem (Wyoming, USA). Methods: For each species, we developed separate distribution models based on climate and forest attributes, projected under four climate‐fire scenarios (a 2 × 2 design with moderate and high temperature and precipitation change). A spatially explicit forest landscape model calibrated for Greater Yellowstone was used to project fire and forest dynamics through 2100, and climate suitability was estimated with MaxEnt. Results: Suitable habitat for all three species based on climate or vegetation alone frequently did not overlap on the landscape, and habitat patches became simpler in shape and farther apart. Climatically suitable habitat for the black‐backed woodpecker increased in all scenarios, and suitable forest structure expanded by a factor of 30 in dry scenarios with more fire. Climatically suitable habitat for martens declined with warming and drying; the area of suitable vegetation fell >80% with fire‐driven losses of mature forest. Red squirrel habitat was maintained in all scenarios, but was sensitive to aridity, and patches were redistributed and compacted. Main conclusions: Projections based on climate alone may misrepresent future species distributions, especially where disturbances accelerate vegetation change. Our results identify important consequences of fire‐regime change for wildlife in forests dominated by obligate‐seeder or fire‐sensitive conifers. [ABSTRACT FROM AUTHOR]

Aim: Protected areas (PAs) play an important role in biodiversity conservation, but remain increasingly threatened by invasive alien plant species (IAPS) in conjunction with global climate change. The latter is modifying the distribution of the former, and the magnitude and direction of distributional changes are predicted to vary depending on species dispersal mode. Here, we address the question of whether clonality is expected to affect the future invasion pattern in PAs. Location: Worldwide. Time period: 1950–2100. Major taxa studied: 36 invasive alien plant species. Methods: We used ensembles of three species distribution models (GLM, GAM and Maxent) based on >70,000 occurrence records to project the distribution of 36 of the world's most invasive clonal and non‐clonal plants in >20,000 PAs. Projections were based on three greenhouse gas concentration scenarios (low, medium and high) for 2080. Results: Climate change showed little impact on the global invasion pattern in PAs, and clonality showed little effect when all biomes were processed in concert. However, we discerned that the future invasion risk of clonal IAPS markedly increased in biomes located at high elevation and high latitude compared with non‐clonal IAPS, while the risk decreased in lower‐elevation tropical and subtropical biomes where asexual reproduction may be a less successful trait. We also showed that invasion hot spots overlapped with biodiversity hot spots and two realms (i.e. Nearctic and Palearctic), which calls for bridging the gap between invasion and conservation sciences and for more concerted management strategies. Main conclusions: We suggest that effective management of IAPS in PAs should consider in which biomes PAs are located as well as the reproductive traits of IAPS that are present or may become so. [ABSTRACT FROM AUTHOR]

Aim: The ongoing global change makes landscape planning and management of ecological corridors crucial to preserve biodiversity. We propose a workflow optimizing the use of different data sources to convert ecological niche models (ENMs) into landscape‐focused species distribution models (SDMs), using these latter to compute ecological corridors. We infer corridors connecting present occurrence localities to future climatic refugia as well as to localities where extinct populations occurred. Also, a continuous connectivity change index is proposed to assess current–future differences. Finally, we discuss possible applications of our workflow to conservation, assessing the capability of established protected areas to preserve ecological corridors. Location: Europe. Methods: As case study to illustrate our framework, we use a database comprising occurrence localities of Vipera ursinii, one of the most endangered European reptiles. We obtain weighted SDMs for each of the four V. ursinii subspecies by coupling climate‐based ENMs with standardized occurrence frequencies along land use and altitude gradients through weighted averaging in GIS. We calculate current and future landscape connectivity for each subspecies based on the corresponding weighted SDM. We compare predictive performance of "traditional" ENMs, including climate, land use and topography as predictors and weighted SDMs. Results: Weighted SDMs outperform ENMs, according to Boyce index. SDMs are used to infer connectivity, predicted to decrease in all future scenarios for V. ursinii, and assess where connections may favour movements of individuals to, for example, future suitable areas. Generally, protected areas are predicted to cover low‐connectivity territories. Main conclusions: The proposed "couple‐and‐weigh" approach could represent a helpful tool to investigate biogeography, conservation and landscape planning topics, as it permits to capitalize on occurrence records and accessible environmental predictors by narrowing the target species' potential distribution, estimated within "traditional" ENMs, to the realized one through post‐modelling GIS analyses, which in turn improves estimation of friction maps used to infer connectivity. [ABSTRACT FROM AUTHOR]

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‐term monitoring approaches, which are crucial for the sustainable management and conservation of marine biodiversity in this unique marine region. [ABSTRACT FROM AUTHOR]