Conservation Letters

1. Global restoration targets, including the Kunming-Montreal Global Biodiversity Framework and the European Union's Nature Restoration Regulation, call for extending restoration beyond protected area boundaries to reconnect isolated ecosystems, yet implementing these landscape-scale interventions forces trade-offs between biophysical effectiveness and social feasibility. 2. In the Grenoble region of the French Alps, we used a gradient analysis of 12 ecosystem services across protected area interfaces to design and compare two restoration scenarios. Both were built from the same set of co-selected interventions but differed only in their spatial allocation: a 'Technical' scenario targeting areas of low ecosystem service continuity around protected areas, and a 'Participatory' scenario co-designed with local stakeholders. 3. Both scenarios physically modified about 14.5% of the landscape, mostly through a forest-based adaptation strategy, yet their effects reached up to more than 60% of the territory for the most connectivity-dependent services, showing that benefits propagate well beyond the area directly modified. 4. The two scenarios diverged mainly in how they treated agricultural land. The Technical scenario reduced abrupt drops in ecosystem service provision at the protected area edge nearly twice as often as the Participatory one (46% versus 26% of the sharp declines it addressed), and at six locations removed them entirely. However, it concentrated over 99% of its non-forest effort in agricultural diversification, such as diversifying crops and adding hedgerows, the action stakeholders ranked hardest to implement, whereas the Participatory scenario favoured more feasible actions such as river restoration, which met less resistance but missed several critical discontinuities in ecosystem service supply. 5. These contrasts show that biophysical potential and social feasibility can pull restoration in different directions, and that the more effective spatial configuration is not necessarily the more implementable one. 6. Closing the implementation gap for nature-based solutions depended less on expanding the area restored than on where interventions were placed. Gradient-based diagnostics appear most useful not as fixed prescriptions but as tools to steer existing sectoral funding in agriculture, urban planning and forestry toward high-impact locations, an approach transferable to other regions working to reconnect protected areas with their surrounding landscapes as coupled social-ecological systems.

The number of species introduced outside of their historical ranges by human activity continues to rise. A subset of these species establishes, form self-sustaining populations, and some (invasive alien species) go on to cause substantial harm to biodiversity and ecosystems. Preventing new invasive alien species from establishing is the key focus of interventions, because post-establishment management is costly and often fails. However, it remains unclear how effective multilateral efforts have been in curbing the rise. Here we show that the emergence of new invasive alien species across countries is slowing, and trends are similarly negative across geographically diverse countries. Using data and modelling advances, we find a 35% reduction in the establishment of new invasive alien species over a policy-relevant 50-year time frame. The findings directly inform the assessment of progress for the invasive alien species target of the Kunming-Montreal Global Biodiversity Framework, and provide a global baseline for monitoring rates of invasive alien species establishment. Furthermore, the slowdown suggests that policy and investment over recent decades to prevent invasive alien species from entering and establishing in countries have had a positive effect.

Businesses are increasingly encouraged to disclose their nature-related dependencies, impacts, risks and opportunities. A common component of sustainability reporting is screening operational sites for ecologically sensitivity to identify locations for further evaluation and action. However, with 600+ biodiversity metrics available, selecting and interpreting appropriate metrics remains challenging for business. We developed a simple screening framework informed by the Taskforce for Nature-Related Financial Disclosures guidance, grouping eleven widely used global biodiversity metrics into four complementary [&prime]baskets[&prime], representing different aspects of biodiversity. We created hypothetical but realistic mining, onshore wind energy and agricultural companies, to assess how metric choice, buffer size, scoring approach and sensitivity thresholds influence screening outcomes. Our basket framework consistently identified similar high-priority sites across metric combinations, but site rankings varied with methodological choices. We recommend clearer guidance on metric selection and application, alongside greater transparency from business regarding assumptions, methods and limitations when screening sites for ecological sensitivity.

Small-scale fisheries provide essential coastal livelihoods in developing regions, yet they often confront severe institutional voids within fragile-state contexts. Adopting a social-ecological systems framework, this study addresses three sequential objectives: characterizing the contemporary institutional and demographic status of fishery cooperatives across the five South-Central Federal Member States in comparison to their late-1980s historical peak; ranking the socio-economic, infrastructural, regulatory, and environmental impediments to cooperative efficacy; and evaluating the contributions of these cooperatives to sustainable fisheries development. This investigation analyzes how fishery cooperatives act as institutional intermediaries to bolster economic resilience within the Somali coastal economy--a sector central to the National Transformation Plan, despite persistent regulatory fragmentation. Through semi-structured qualitative interviews with key informants--analyzed via reflexive thematic analysis and chi-square testing of age-cohort structure--the study finds that illegal, unreported, and unregulated fishing and inadequate post-harvest infrastructure are the principal constraints, whereas training, education, and community collaboration constitute the primary contributions. The results characterize these cooperatives as hybrid institutions that compensate for limited central-state capacity in remote coastal settlements while serving as intermediaries for the Federal Ministry of Fisheries and Blue Economy where co-management mandates are implemented. By extending the actor-community dimension of the SES framework to include age-cohort structure, this research demonstrates that clan-based reciprocal arrangements can serve as functional substitutes for Ostroms first design principle in contexts of persistent fragility. The study recommends multi-stakeholder partnerships to advance targeted capacity-building, financial literacy, and technological integration, and suggests future research into the post-harvest and retail sectors to examine the role of women in the Somali blue economy.

Incorporating the complexities of climate change into conservation planning can be challenging. Climate change is projected to change the mean and variability of temperature and precipitation, and change dynamics of extreme events of many climate variables globally. These changes will all have compounding effects on ecosystems worldwide, affecting species distributions, seasonal timings, and population dynamics. However, most recent climate-informed conservation planning frameworks only focus on changes in mean conditions, leaving out ecologically important information about seasonality and extreme events. Using a case study of estuaries in the Pacific Northwest, this research seeks to answer the question "How can the effects of climate change on estuaries best be modelled and described for practical use in ecological management?" To answer this question, we used downscaled climate projection data to estimate changes in the mean and variability of temperature and precipitation. Applying extreme value theory to these projection data, we also projected changes in the magnitude of extremes in temperature and precipitation for estuaries in the region. Using descriptive statistics and open source data, our results present a novel, holistic method of understanding climate risk, including estimating extreme events, highlighting a key research gap in conservation planning. These results also highlight that trends in the mean, variability, and magnitude of climate extremes are not consistent with each other, further underscoring the importance of considering multiple dimensions of climate change together. Despite uncertainty given by climate models, the methods presented here provide a reasonable approach to plan for conservation management in the face of climate uncertainty.

Reliable population estimates are essential for wildlife management, yet monitoring schemes often do not match the administrative scale at which decisions are made. We illustrate this challenge using the Eurasian lynx in the canton of Valais, Switzerland, where official state monitoring is fragmented across three reference areas surveyed in different years. We analyzed three winters (2023-2026) of independent, canton-wide camera trap data, recording 899 independent lynx captures (27, 31 and 34 adults per winter). Lynx distribution and reproduction concentrated in the Northwest and connected to the thriving Pre-alpine populations. Density modelling for 2025/2026 estimated 37 independent lynx (95% CI: 26-52) on the whole cantonal territory, corresponding to a density of 1.09 (0.77-1.56) individuals per 100 km2. These estimates are substantially below the figures improperly extrapolated from a cross-cantonal reference area and conveyed by political authorities. Future lynx management decisions should be rooted in scientifically sound, scale-relevant information.

Conserving migratory birds effectively requires full annual cycle strategies that identify where on-the-ground efforts can have the greatest impact. Here, we present a hemispheric spatial framework to identify priority areas for 112 migratory bird species across the Americas. Building on full annual cycle prioritizations, we defined finer-scale spatial planning units that reflect differences in migratory and congregational behaviors between shorebirds and landbirds. We compiled population data for each planning unit and focal species and applied conservation planning tools to design area-efficient portfolios of sites and landscapes that secure 10% of each species population within the Americas flyways. The resulting minimum area portfolios include 175 shorebird sites and 80 landbird landscapes optimized to meet the species-specific 10% representation targets across breeding, non-breeding, and passage seasons. We also identified a broader set of complementary solutions, ranked by an importance score, to provide decision-makers with flexible options for strategic resource allocation. This framework provides the scientific foundation for the Americas Flyways Initiative (AFI), which aims to catalyze investment in nature-based solutions and bird-friendly infrastructure to enhance the conservation of migratory birds and strengthen the resilience of the Americas flyways by 2050.

Chinstrap penguins (Pygoscelis antarcticus) in the Antarctic Peninsula and Scotia Arc regions (CCAMLR subareas 48.1 and 48.2) have experienced substantial declines, yet uncertainty remains about regional variation and conservation priorities. We applied a Bayesian hierarchical model to 1,072 nest counts from 194 colonies (1970 to 2024) to quantify population trends, estimate probabilities of exceeding IUCN Red List thresholds, and assess compensation potential across four locations. The regional population declined by 41.9% over three generations, with 91.4% probability of exceeding the 30% Vulnerable threshold but only 9.2% probability of exceeding the 50% Endangered threshold. Declines were spatially heterogeneous: South Shetland Islands (40.2% of regional population) declined by 74.7% with near-certainty of exceeding both thresholds, while South Orkney Islands showed stability with high uncertainty (median -5%, 95% CI: -31.5% to +36.8%). The probability of increasing colonies compensating for regional losses was only 7%. These results support a three-zone conservation strategy for CCAMLR's proposed Marine Protected Area: urgent protection for the South Shetland Islands, enhanced monitoring for South Orkney and Elephant Islands, and adaptive management for the Antarctic Peninsula. Our uncertainty-quantified framework provides evidence-based guidance for balancing krill fishery access with predator protection in a rapidly changing Southern Ocean.

Fishing pressure has substantially increased over time and elasmobranchs are among the most vulnerable marine taxa impacted. 'Small-scale' and 'large-scale' are terms frequently used to describe fisheries, yet definitions used across the globe are inconsistent. The global impact of small-scale fisheries on elasmobranch decline is increasingly evident. However, ambiguous vessel-capacity classifications undermine effective conservation management. Technological advancements have led to the emergence of medium-capacity vessels that sit between small and large-scale classifications, creating regulatory gaps that increase bycatch impacts on vulnerable elasmobranchs. Beyond vessel size, the gear specificities and practices also affect interaction with species caught incidentally, and can alter bycatch risk for vulnerable elasmobranchs. Manta and devil rays (collectively, mobulids) represent a pelagic ray group that includes species listed as Critically Endangered with high risk of extinction, largely due to bycatch threats. To prioritise fisheries management for conservation, we assess the contribution of fishing gear specifications and practices to mobulid bycatch as a case study in their largest fishery globally. We use a Huber-robust extension to a Hurdle negative binomial model to assess the impact of fishery characteristics and operational specificities on mobulid bycatch risk. We find that within the Food and Agriculture Organization (FAO) of the United Nations' broad international fleet classification of small-scale vessels based on overall length ([≤]24 m), the 'medium-capacity vessels' in India are twice as likely to catch mobulids than small-scale vessels. Further, increased fishing intensity, measured in five-day increments, doubles mobulid bycatch risk. Our results indicate the emergence of a distinct medium-capacity fishery class in rapidly developing blue-economy nations, shaped by rising technological capacity and exemptions from large-scale management measures. We propose a comprehensive re-conceptualisation of small-scale fisheries to ensure that advanced medium-capacity vessels are subject to management measures commensurate with their bycatch impact. Our recommended re-conceptualisation is complementary to FAO's SSF characterisation matrix and would promote fishery-level sustainability and enable bycatch risk mitigation for elasmobranchs, including manta and devil rays. Further, for congruence between elasmobranch demography and regulations, we recommend that fisheries management measures distinguish vessel capacities for elasmobranch bycatch risk and apply biologically relevant regulations to the associated fisheries scale.

Achieving global conservation and restoration targets requires knowing not only how much land to conserve and restore, but also where such actions will have the greatest ecological effect. Conservation and, in particular, restoration priorities are often inferred from habitat condition, opportunity, or broad ecological value, yet these criteria do not necessarily identify where local changes generate the largest landscape-scale consequences. Building on sensitivity-based conservation prioritization, we extend the approach to derive ecological loss and gain potential by differentiating a persistence-relevant connectivity metric with respect to local habitat condition. Sensitivity identifies areas where local degradation or improvement would most strongly affect connected habitat at the landscape scale. Combining sensitivity with current condition distinguishes high loss potential, where degradation would have large ecological consequences, from high gain potential, where ecological improvement could generate large benefits. Applying the framework to national forest-naturalness data in Norway, we show that loss and gain potential are spatially related but far from redundant, and that gain potential is not simply concentrated in the most degraded forests. Both high-loss and high-gain areas were poorly represented within current protected areas, although loss potential was consistently better represented than gain potential. Extending sensitivity-based prioritization in this way provides a general and scalable means of linking local habitat-condition change to persistence-relevant landscape outcomes, while distinguishing the ecological potentials that can inform conservation and restoration decisions.

Arthropods represent the most species-rich animal group on the planet, yet they remain largely overlooked in formal conservation planning. New Mexico is a US state with exceptional biodiversity, including numerous endemic, rare, and threatened arthropod species. Recent attention to global insect declines has highlighted the need to document possible threats to and declines of New Mexico insects and other arthropods. All terrestrial arthropods in New Mexico lacked state-level regulatory protection until 2025, and baseline data on the taxonomy, ecology, geographic distribution and conservation needs for most New Mexico arthropod species remained absent. To address this gap, we developed the New Mexico Rare Arthropod Resource (NM-RARe), a publicly accessible regional database for arthropod species and subspecies of conservation concern in New Mexico. Drawing from multiple vetted sources, we compiled an initial working list of 7,018 taxa and conducted 261 preliminary IUCN Red List assessments and 185 NatureServe state rank assessments, covering 285 total taxa. Of those assessed by IUCN Red List standards, 52 were subspecies and 209 were species level assessments, 165 of which met the criteria for inclusion and were incorporated into the NM-RARe database (https://nmrare.org/). Ninety-three of the pollinating insect species from NM-RARe were then formally incorporated into New Mexico's 2025 State Wildlife Action Plan (SWAP), representing a significant conservation milestone. Beyond its immediate regional impact, NM-RARe presents a standardized, scalable methodology adaptable to any region or taxonomic group, offering a replicable framework for arthropod conservation assessment worldwide.

Exotic pests and pathogens pose a major threat to forest ecosystems. Early detection of newly introduced organisms is critical for implementing effective eradication measures before they become established. Citizen science platforms have emerged as promising sources of biodiversity data for detecting invasive pests and pathogens, yet their integration into formal biosecurity surveillance remains limited. Using France as a case study, we surveyed 101 professionals involved in forest and urban tree management and pest surveillance to assess their knowledge of regulated tree pests and pathogens and their attitudes towards online citizen science platforms for biosecurity applications. We focused on ten focal species representing different regulatory statuses under EU legislation. We assessed the knowledge professionals have of these species and their regulatory status, and explored sources of variation in their opinions regarding the use of citizen science platforms as a tool for post-border biosecurity. Experts involved in mandatory surveillance of regulated organisms (SORE experts) demonstrated consistent knowledge of quarantine pests, whereas other professionals knowledge varied by species, with greater familiarity for non-quarantine, widely distributed pests. Half of respondents used citizen science platforms, predominantly to consult species distribution rather than to contribute observations. Professionals receptivity to citizen science increased significantly when species were perceived as easy to identify, but they expressed more confidence in citizen science for monitoring established pests than for the early detection of quarantine species. The survey reveals that while citizen science platforms are known and valued as information sources, they remain underutilized as mechanisms for sharing field observations, even among surveillance professionals.

1. Assessing the conservation value of secondary forests and reforestation is important for conservation planning. Butterflies are widely used as indicators, and fruit-feeding butterflies are often used in biodiversity assessments in tropical landscapes. 2. We examined fruit-feeding butterfly diversity, abundance, and community composition across a primary forest, a secondary forest, and a plantation forest in northern Vietnam. We sampled butterflies nearly monthly during one year using baited traps. 3. Primary and secondary forest supported higher species richness than plantation forest. Moreover, while secondary forest had mainly a subset of species found in primary forest, the plantation forest had a distinct butterfly fauna. 4. Butterfly abundance and community composition varied across months, without showing a clear seasonal pattern. 5. Our results suggest that secondary and plantation forests do not fully replace primary forests, but they contribute meaningfully to butterfly conservation in human-modified tropical landscapes.

Environmental concerns and the need to mitigate the effects of climate change have driven the adoption of renewable energy sources, such as offshore wind farms (OWFs), making it essential to assess their overlap with seabird habitats to estimate potential impacts. This study is the first to estimate the vulnerability of coastal and seabirds to OWFs at a national scale by integrating biological trait data from the literature, spatial occurrence records from citizen science platforms, and expert knowledge (elicited from 23 specialists) into established quantitative risk frameworks. Collision risk and susceptibility scores were calculated at the family and subfamily levels, as well as disturbance and displacement indices by species and susceptibility by state. The groups with the highest collision risk and susceptibility were Fregatidae (0.354; 0.486), Sulidae (0.199; 0.419), Sterninae (0.190; 0.384) and Diomedeidae (0.190; 0.416). The extreme risk for Fregatidae is driven by their specific flight characteristics, with impacts concentrated in the highly frequented southeast and northeast regions. Regarding disturbance and displacement, Limnodromus griseus exhibited the highest national score (MMA: 0.098), while Diomedea dabbenena had the highest global score (IUCN: 0.092), highlighting the critical need to integrate both regional and global conservation statuses. Spatially, the state exhibiting the highest overall vulnerability to OWF impacts was Rio Grande do Sul (23.78; 10.69), a critical hotspot characterized by high species richness and oceanographic productivity. These findings establish an indispensable national baseline for Marine Spatial Planning, reinforcing the need for targeted pre-installation assessments, the identification of sentinel species, and spatially differentiated management during environmental licensing processes.

Understanding how scientific effort is distributed is essential for evaluating the evidence available to guide species conservation. We assessed the temporal, thematic, methodological, and spatial organization of jaguar (Panthera onca) research across the species range. Using 1,028 bibliographic records, we applied a metadata-based scope filter, defining a primary analytical corpus of 857 articles and an inclusive sensitivity corpus of 989. We analyzed publication growth from 1946-2024, author-keyword networks, high-specificity research-domain and methodological indicators, article-based spatial concentration across nine regions, and anthropogenic context using the Human Impact Index. Publication output increased strongly and nonlinearly, with the negative-binomial generalized additive model explaining 96% of deviance. Population and abundance, human-wildlife conflict and coexistence, and movement and connectivity were the most frequent research domains, whereas camera trapping was the most frequent methodological approach. Spatial analyses included 237 georeferenced terrestrial articles. Research was strongly concentrated in the Pantanal, Mesoamerica, and Atlantic Forest, but was underrepresented relative to range area in the Andes and Choco-Darien, Amazon, and Guiana Shield. These patterns were stable to the broader scope definition. Research concentration showed no strong association with region-wide anthropogenic pressure, although studies within several extensive regions tended to occur in more human-influenced portions than the regional average. Jaguar research therefore shows substantial growth and partial alignment with applied conservation challenges but remains geographically uneven. Expanding representative research in underrepresented regions, while maintaining work in threatened landscapes, would strengthen the evidence base for range-wide conservation planning and improve coordination among countries, institutions, and regional research traditions.

Increasing fishing pressure, including from small-scale fisheries, has caused declines in more than one-third of all elasmobranch species. Tackling conservation issues in small-scale fisheries requires interdisciplinary approaches due to the coastal community's interdependence on marine resources. To support inclusive policy change and fisher engagement, an understanding of the motivations driving fishers' operational choices (i.e., the retention of elasmobranch bycatch) is needed. We assess the motivational drivers behind bycatch retention of one of the slowest-growing and most vulnerable elasmobranch groups, manta and devil rays (collectively, mobulids), through a case study in India, their largest fishery in the world. We conducted a best-worst scaling survey in the fishery-intensive states of Tamil Nadu and Andhra Pradesh, which make significant contributions to mobulid landings on India's east coast. Our results suggest that fishers exhibit varied motivations for retaining mobulid bycatch across states. Financial motivation to sell mobulids for additional revenue was the most important motivator for bycatch retention in both states. In Tamil Nadu, the top three motivators were all financially driven, whereas in Andhra Pradesh, the top three motivators included both financial and non-financial attributes, such as nutritional importance and storage optimisation. As the first socio-economic study of mobulid fisheries in India, we show that motivations underlying bycatch retention decisions vary geographically and may be influenced by cultural differences between states and the socio-economic characteristics of decision makers. Based on identified fisher motivations, we provide context-specific recommendations to align conservation strategies with the values fishers derive from the mobulid fishery and encourage participation in conservation. These include subsidies for net repair to encourage mobulid release; promotion of a minimum price measure for sustainably sourced alternative species; quality improvement of target species; and increased awareness of national and international regulatory obligations (e.g., CITES, CMS, IOTC).

Stony coral tissue loss disease (SCTLD) has caused one of the most damaging coral epizootics on record, impacting about half of coral species across most of the reef systems of the Caribbean and Florida. To evaluate its impact on the coral reefs surrounding Carrie Bow Cay, Belize, we monitored seven fixed transects before and at two time points during the outbreak using three different methods. We estimated species-specific mortality rates by fate tracking tagged colonies, quantified reef-wide lesion prevalence and resulting changes to colony density and community composition using in situ transect surveys, and finally calculated changes to total coral cover using benthic photoquadrats. SCTLD quickly led to mortality of infected corals. Between October 2019 and May 2022, 32% of the 102 fate-tracked coral colonies had developed lesions consistent with SCTLD and an additional 30% had suffered complete mortality likely due to SCTLD. By December of 2022, 21% of the 33 colonies that had been observed with lesions had died. We documented patterns of species susceptibility largely confirming previous reports in other locations. We documented sharp abundance declines in several species, including the total loss of Meandrina meandrites from survey transects, leading to a significant shift in community composition. Cover of several species declined between October 2019 and May 2022, but only Siderastrea siderea experienced sustained declines into December of 2022. Overall cover of scleractinian corals decreased from 13.2 to 7.9% during the monitoring period. The ecological impacts of SCTLD in the area surrounding Carrie Bow Cay are consistent with reports from elsewhere in the Caribbean, underscoring the magnitude of colony density and coral cover loss caused by SCTLD across the region.

Coral bleaching is among the most infamous climate impacts. Yet the extent of bleaching due to human-caused climate change, as opposed to natural El Nino variability, and the contributions of individual countries and carbon majors (fossil fuel and cement producers) remains unquantified. Here, we leverage coral monitoring globally across 4,479 sites from 1985-2024 to link specific emitters to marine heat stress and bleaching. For events with >10% of corals bleached at a site, we find that 99% (95% CI: 88-100%) were attributable to human-caused climate change. Even during major El Ninos, 97-100% of bleaching events were attributable to human-caused climate change and the extent of damage increases over time from 23% of sites bleached (95% CI: 3-35%) during 1998 to 71% of sites (95% CI: 37-85%) during 2023-2024. Emissions of the United States, the largest historical emitter, contributed to 51% (95% CI: 39-65%) of bleaching events. Emissions linked to Chevron, Saudi Aramco, Gazprom, and ExxonMobil each contributed to 14% (95% CI: 11-19%) of bleaching events -- roughly double the contribution of the 39 countries of the Alliance for Small Island States. It is virtually certain emissions of China, the United States, and Indonesia caused bleaching in their coastal waters. Strong inequalities exist where countries with high socioeconomic dependence on coral reefs experienced 54% of bleaching yet contributed only 5% to bleaching. As global warming rapidly nears levels catastrophic for warm-water corals, our results show the massive contribution from anthropogenic emissions to historical coral beaching and help fill an important evidentiary gap on accountability for non-economic loss and damage from climate change.

The Community Conservation Index (CCI) developed by Chadd and Extence (2004) has been widely used to assess the conservation value of freshwater macroinvertebrate assemblages by integrating species rarity and community richness into a single metric. However, the original conservation scoring system was based largely on historical rarity designations and regional distribution data that no longer reflect current conservation assessments or recording coverage. This paper presents a comprehensive revision of the Conservation Scores underpinning the CCI. Species scores were updated using the latest IUCN-compliant Red List assessments for British freshwater invertebrates. For taxa classified as Least Concern, Data Deficient, or lacking a recent conservation assessment, scores were derived from national occurrence data across Great Britain for the period 1995-2024 using hectad occupancy. In addition, all non-native species were assigned a conservation score of zero to ensure they do not contribute positively to site conservation value. The revised dataset includes 1,680 taxa, compared with 1,117 in the original index, with 755 taxa receiving Conservation Scores for the first time. Thirty non-native taxa were assigned a score of zero. Among previously scored taxa, 165 received higher scores, 576 received lower scores, and 184 remained unchanged. The predominance of score reductions reflects improved knowledge of species distributions and the replacement of historical rarity classifications with contemporary assessments based on conservation status and national frequency of taxon occupancy. The revised CCI maintains the original strengths of combining rarity and richness while improving transparency, consistency and ecological relevance. By incorporating current Red List assessments, Great Britain-wide distribution data and revised treatment of non-native species, the updated index provides a more robust and nationally representative measure of freshwater macroinvertebrate conservation value. It offers an enhanced tool for biodiversity assessment, conservation prioritisation, site designation and environmental decision-making across freshwater ecosystems in Great Britain.

1. Occurrence records underpin biodiversity analyses, but their coordinates are often erroneous or missing. Misplaced coordinates distort environmental predictors and range estimates used in conservation assessment. Existing tools flag suspect records or georeference locality text, but rarely correct coordinates, provide calibrated uncertainty, or quantify downstream consequences. 2. We present GeoMend, a deterministic, rule-based method that flags and corrects suspect coordinates and georeferences records lacking coordinates from locality text, assigning each a precision tier or uncertainty radius. It uses no machine learning or artificial intelligence. We evaluate it against expert coordinates for 16,913 records and 736 species on Hispaniola, compare georeferencers using 5,000 localities from 72 countries, and measure changes in environmental predictors and the extent of occurrence. 3. On held-out Hispaniola records, GeoMend flags 92% of coordinates more than 5 km from expert truth, versus 27% for CoordinateCleaner. Among the accepted corrections with paired coordinates, the median error falls from 2.19 to 0.82 km, and 68% of the complete held-out pairs improve. On records placed by both GeoMend and GEOLocate that also have original coordinates, the median error is 0.67 km for GeoMend versus 10.69 km for GEOLocate. For records lacking coordinates, evaluated uncertainty radii contain expert truth about 92% of the time in well-supported gazetteer classes. Correction reduces the mean standardized environmental distance from expert truth by 38% and moves the extent of occurrence toward expert truth by a median of 8% (mean of 79%). Corrections and newly georeferenced records give 17 Hispaniola species their first range estimate. 4. On the global benchmark, GeoMend is more accurate than GPT-4o for two-thirds of the records placed by all four comparators, with median errors of 4.4 and 10.8 km, respectively. Applied to Global Biodiversity Information Facility (GBIF) records lacking coordinates, it places records from 82,180 previously unmapped species across 233 countries, ranging from precise locality interpretations to administrative centroids. Automated placement makes the global backlog more approachable, while explicit tiers distinguish uses supported by precise and coarse coordinates. Further georeferencing requires regional expertise to combine automated placement with local knowledge.