Biological Conservation

Controlling invasive species is a global conservation priority but is typically resource-limited, necessitating strategies to optimize control. Spatial prioritization methods can improve the efficiency of invader control by quantifying the benefits, costs, and risks of alternative intervention strategies. Yet prioritization designs are sensitive to the distinction between protecting native populations that are currently sympatric with invaders versus safeguarding presently allopatric native populations by preventing invader expansion. Gaining a better understanding of this distinction stands to improve our ability to prioritize the management of invaders whose distributions--and thus impacts on native species--are dynamic. We asked how prioritization designs addressing current versus future invader threats affected tradeoffs among focal species protection, biodiversity conservation, disturbance risk, and overlap with existing conservation infrastructure. As a case study, we spatially prioritized population control of invasive barred owls (Strix varia) in the northwestern US. We found that distinguishing between current versus future threats posed by barred owls to the native spotted owl (S. occidentalis) strongly mediated whether invader control stood to benefit native at-risk animal communities. Furthermore, this distinction also affected the degree to which population control would overlap with fire risk and federally protected forests, both of which plausibly affect the viability and success of conservation action. These results thus illustrate that deciding to prioritize the control of invaders based on their current versus future impacts on native species can dramatically affect the distribution and characteristics of high-priority areas for management. Our findings also directly inform control of barred owls in the northwestern US: we found that prioritizing future threats to spotted owls could protect at-risk amphibian communities from novel barred owl predation, but that high fire risk and minimal protected forest may complicate implementation. Thus, in both our system and more broadly, spatial prioritization methods are an important tool for quantitative, reproducible, and successful invader control.

Conservation biology increasingly relies on ecological forecasting, yet the biodiversity components most urgently targeted by conservation, such as rare species, local assemblages, and hotspot-defined communities, are often those whose dynamics are least predictable. Understanding how predictability varies across biodiversity is therefore essential for aligning management tools with their targets. This study tests whether predictability varies along three axes, how diversity is measured, the spatial scale of observation, and the temporal forecast horizon (which together govern the effective signal-to-noise ratio of ecological dynamics), and uses these patterns to inform conservation strategies. Using long-term monitoring data from seven estuaries along the Texas Gulf Coast, forecasting performance was evaluated for Hill diversity (q = 0, 1, 2) and population-level abundance of eight dominant taxa at local (bay) and regional (coastwide) scales across near-term (1-month) and long-term (12-month) horizons. Multiple time-series model classes were assessed within a rolling-origin cross-validation framework, with performance measured as improvement in root mean square error over a seasonal naive baseline. Forecasting performance increased consistently with Hill number order, reflecting reduced stochastic variation as dominant species are emphasized. The effects of spatial aggregation differed between systems. Aggregation generally improved performance for littoral assemblages but provided limited or no benefit for demersal assemblages, consistent with differences in how predictive signals are distributed across space. Forecast skill declined from 1-to 12-month horizons, with slower decay for dominance-weighted diversity and demersal assemblages than for rare-species-weighted richness and littoral assemblages. Environmental covariates provided limited near-term gains but became an increasingly important source of predictive information at longer horizons for a subset of demersal and crustacean targets. These results define a predictability landscape structured by diversity measurement, spatial scale, and forecast horizon. Three conservation domains, stochastic, transitional, and structured, emerge from this framework, each associated with distinct predictability regimes and management strategies. Aligning conservation approaches with the predictability properties of their targets provides a principled basis for determining when forecast-based management is informative and when precautionary approaches are more appropriate.

Semi-aquatic mammals lie at the intersection of several key conservation issues such as wetland deterioration or species invasions, and monitoring their distribution in space and time is essential to inform conservation strategies. However, gathering information about their presence is challenging due to their elusive lifestyle and generally low abundance. The Eurasian otter (Lutra lutra), a near-threatened and strictly protected species in Europe, is currently recolonizing part of its historical range. Its high conservation interest, combined with a dynamic more commonly associated with range-expanding or invasive species, makes it a particularly compelling case study. Otter monitoring has traditionally relied on scat surveys, but recent environmental DNA (eDNA) and camera-trapping initiatives have emerged offering promising complementary tools. Yet, these approaches have rarely been formally compared, either to one another or across regions. Here, we compared the efficiency of spraint surveys, camera traps, and eDNA for detecting otters, and assessed how their performance varied among four catchments in southern France where the species is known to be present. All three methods provided otter detections with varying efficiency. Scat surveys were the most effective method, with an average detection probability of 0.71 and no strong variability between catchments. Although camera-traps had the lowest detection rate, they provided detections at two of the four sites where no spraint was found, highlighting the complementarity of these two approaches. Detection rates varied greatly between individual cameras rather than between catchments, underscoring sensitivity to camera-placement. eDNA showed important variability between catchments, with detection probabilities differing by roughly sixfold across regions. All in all, our results highlight differences in efficiency between methods and across environmental conditions, and show the value of combining approaches for future monitoring programs.

Effective conservation depends on demographic metrics that reliably reflect species status, particularly population abundance. For elusive species occurring at low densities, however, such metrics remain difficult to obtain. Spatial capture-recapture (SCR) models are the standardized approach for estimating density in marked populations, but their data requirements, especially the need for multiple spatial recaptures across individuals, often limit applicability in small or data-poor populations. This constraint has resulted in knowledge gaps for some of the most vulnerable species, undermining evidence-based conservation planning and management. Using camera-trap data and SCR-derived density estimates from data-rich populations, we evaluated alternative, less data-demanding metrics and tested the hypothesis: Space to Event (STE), Mean Local Abundance (MLA), and Relative Abundance Index (RAI) exhibit predictable relationships with SCR-derived density; if supported, these metrics can reliably estimate density in populations where SCR models cannot be implemented. We applied this framework to the European wildcat (Felis silvestris), an elusive small felid with highly fragmented populations across Europe, for which density estimates are largely lacking despite growing conservation concern. Across 21 study areas spanning most of the species' range, our results indicate that European wildcats generally occur at lower densities than previously reported. SCR-derived estimates (n=10) averaged 10.32 {+/-} 11.56 inds/100km2, while STE enabled density estimation in five additional data-poor areas (mean 5.52 {+/-} 5.33 inds/100km2). STE showed a strong linear relationship with SCR-derived density (R2=0.98), supporting its use as a viable alternative when SCR is infeasible, although it tended to underestimate compared to SCR, especially at higher densities. In contrast, MLA and RAI showed weaker and non-linear relationships with SCR-derived density (R2=0.65), indicating substantially lower explanatory power and suggesting their estimates are more strongly influenced by confounding processes. By explicitly calibrating alternative metrics across a wide density gradient throughout most of the species' distribution, this study provides a transferable methodological framework for estimating density in low-density wildlife populations and the first continent-wide, standardized density assessment of a carnivore species. From a management perspective, our findings identify populations that may be most vulnerable, particularly those with the lowest densities, and highlight the need to prioritize absolute abundance monitoring.

The choice of appropriate methods to detect species is crucial for biodiversity monitoring. Camera trapping is currently one of the most widely used methods for characterizing mammal communities, although it requires substantial investment in equipment and personnel. In contrast, questionnaires administered to local populations provide a faster and more cost-effective alternative for assessing community composition, but may be influenced by respondent-related biases that compromise data reliability. This study evaluates the concordance between these approaches for characterizing the carnivore community in the Sierra de Segura (Jaen, southern Spain), using Cohens kappa coefficient, while also examining the individual and social factors shaping Local Ecological Knowledge (LEK). We deployed 24 camera-trap stations (144 trap nights) across a 25 km2 area to record carnivore presence. In parallel, we conducted two types of surveys with local residents (n = 103): (i) free-listing and (ii) image-based species recognition, while recording individual and social characteristics of respondents. Free-listing surveys tended to underreport species, whereas image-based surveys showed higher agreement with camera-trap data, although occasionally overestimating species presence. Higher concordance was associated with social factors indicative of closer and prolonged contact with the environment, such as permanent residence and ownership of agricultural land. Mammal communities differed between methods; however, agreement improved when respondents had higher LEK, while species-specific behavioral traits could also influence perception. Our findings demonstrate that image-based questionnaires can provide results comparable to camera trapping when respondents have strong connections to their natural surroundings. These results highlight the importance of both survey design and respondent selection in improving the accuracy of biodiversity monitoring, offering a transferable framework for integrating LEK into conservation protocols across diverse ecosystems. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=126 SRC="FIGDIR/small/720805v1_ufig1.gif" ALT="Figure 1"> View larger version (35K): org.highwire.dtl.DTLVardef@d55c34org.highwire.dtl.DTLVardef@1985c66org.highwire.dtl.DTLVardef@1da576aorg.highwire.dtl.DTLVardef@1a10ccb_HPS_FORMAT_FIGEXP M_FIG C_FIG

Native vegetation protection is a key strategy for delivering both biodiversity and climate benefits, and protected areas have been widely adopted to keep tropical biomes standing. Yet deforestation is driven by interrelated environmental and social factors, and the effectiveness of protected areas varies considerably across space. Here, we evaluated the impact of 802 protected and conserved areas in the Brazilian Amazon on preventing vegetation loss and avoiding carbon emissions over the past 40 years using statistical matching to address the location bias of protection. We found that protected areas were effective throughout the study period, reducing the probability of deforestation per km2 by an average of 0.5 percentage points per year. While the Amazon biome lost 14% of its native vegetation between 1986 and 2024, protected areas prevented the deforestation of 290,436 km2, nine times their actual internal loss. They also stored 45,336 Mt of carbon in 2016 (61% of the Amazon stock) and prevented the emission of 7,300 Mt of CO2 by 2024. Deforestation inside the areas and remoteness reduced their impact, while areas that were initially more preserved were more effective. Area size and age had no influence over impact once we analyzed the amount of avoided deforestation per size and age. Impact also varied across Brazilian states, highlighting the role of regional context. All three protection categories (conservation units, indigenous lands, and quilombola territories) showed a positive mean impact, indicating that each, in aggregate, contributes to reducing deforestation. These findings provide robust evidence of the substantial role of Amazonian protected areas in habitat conservation and climate mitigation, while underscoring that this contribution remains undervalued. We advocate for strategically expanding protection to areas of greatest potential impact, and for securing adequate funding to ensure protected areas can fulfill that potential.

The small mammals in the tropical savannas of northern Australia, have undergone a degree of change in recent decades, best documented in the Northern Territory. Data is limited from northern Queensland and though the same trends are assumed, the topographic and climatic features differ substantially. In this study we examined data systematically collected from 725 sites between 1998-2012 in three bioregions representing a climatic gradient: from semi-arid to monsoon tropical savannas. We investigated via information-theoretic models and model averaging, the relationship between five mammal groupings and three landscape variables (fractional cover green, elevation and vegetation diversity) to elucidate any consistent or different patterns in the mammal fauna. Key patterns included relationships with increasing elevation (critical weight range species richness positively associated with elevation, rodent species richness negatively associated), increasing rodent and dasyurid species richness with vegetation diversity, and lower macropod and dasyurids abundance with increasing fractional cover green. These relationships underscore a need to consider mammal conservation in Queensland with more nuance than in the more topographically inert Northern Territory. Management strategies need to be more attuned to taxonomic and regional differences, to prevent perverse outcomes.

ContextFire is a key driver of wildlife pattern in northern Australia, and in recent decades there has been concerted efforts to return burning practices from unmanaged wildfire to approaches more in tune with traditional approaches to fire management undertaken by First Nations people. AimsWe examined fire pattern (early and late dry season) and distance from coast in relation to mammal pattern on a Cobourg peninsula, as there was some evidence in variable patterns in fire history and mammal persistence in this landscape. MethodsIn this study we examined data collected from Garig Gunak Barlu (Cobourg) National Park, Northern Territory, between 2004 and 2017. We investigated the relationship between all native mammal abundance and species richness, and abundance for eight species, with the three environmental variables (distance from coast, preceding early dry and late dry season burning frequency), using an information theoretic model selection and averaging framework. Key resultsThere is a distinctive change in the fire and mammal pattern with respect to distance from the coast; that is, early and late dry season burning increasing moving inland from the coast, and a concomitant decrease or persistence in some key species on this fire gradient. ConclusionsOur results suggest that fire management in northern Australia still needs targeted research linked to active management to more effectively prevent declines of mammal populations. ImplicationsThe location and shape of Garig Gunak Barlu (Cobourg) National Park provide an excellent opportunity to undertake some natural experiments in strategic burning to investigate improved approaches to conservation in fire-prone landscapes.

O_LIWhen eradication is unfeasible, invasive predator control should evaluate how removal affects ecological responses by native species. Assessments often use total invasive predator abundance to evaluate prey responses, yet intraspecific variation in diet and space use means that some subgroups cause disproportionate impacts. Identifying these problem individuals, and the spatial scales over which their impacts operate, can enable targeted spatially explicit removal to maximise impact reduction. However, despite individual-level information is often already collected during trapping operations it is seldom included when analysing predator impacts, potentially biasing the conservation outcomes expected under blanket removal. C_LIO_LIWe use a novel framework and two decades of invasive predator control data to estimate how individual variation in residency status influences the distance-dependent impacts of invasive American mink Neogale vison on water vole Arvicola amphibius occupancy across two prey surveys. We also develop a sub-model to predict mink residency status for individuals with missing age data. C_LIO_LIThe probability of capturing adult mink decreased with elevation and years of control, indicating that long-term control altered the resident population and demographic composition of mink around water vole sites. C_LIO_LIDistance-dependent negative impacts of mink varied by residency status, becoming negligible at approximately 20 km from water vole sites for resident mink and 2 km for transient. The spatial scale of mink impacts was largest during the first vole survey when resident mink were more abundant, and declined rapidly for the second survey, when mink were less abundant and spatially clustered. Our results suggest that water voles have benefited mostly from reducing resident mink rather than the total population, especially in early control phases. C_LIO_LIManagers can use our framework to develop spatially explicit and impact-based strategies, not restricted to invasive species control, to construct empirically informed management buffers around populations of conservation concern. Long-term efforts will change the landscape and invasive predator contexts, and thus we recommend iteratively updating and re-evaluating management outcome evaluations. We argue that incorporating individual heterogeneity improves our understanding of ecological mechanisms influencing management success but that the suitability of targeted strategies should be evaluated for target socioecological contexts. C_LI

Land-use and land-cover (LULC) change is a dominant driver of biodiversity loss, yet its long-term role in restructuring species distribution remains poorly understood due to limited historical baselines and the scarcity of long-term analyses across multiple ecological transition zones. Here, we investigate nearly two centuries of land-use change across a biogeographically diverse region to evaluate how landscape transformation has reshaped vertebrate distribution range dynamics, and whether ecoregional context, habitat specialization, and taxonomic identity better explain these patterns than recent landscape change alone. Using Texas, a biogeographic crossroads with diverse ecoregional zones and a long history of intensive land-use, we quantify distributional changes in 100 native vertebrate species (mammals, birds, reptiles, and amphibians), using Vernon Baileys late nineteenth-century surveys as a historical benchmark. We integrated multi-temporal LULC datasets with spatial and multivariate analyses to assess how habitat change, species traits, and regional context relate to patterns of range expansion, contraction, and redistribution. We show that Texas has undergone non-linear landscape transformations characterized by early agricultural expansion followed by cropland abandonment, shrubland encroachment, and rapid urbanization. Range contractions were most pronounced among amphibians, reptiles, and habitat specialists, whereas generalist species and many birds exhibited greater range stability or expansion. Across taxa, primary habitat, vertebrate class, and ecoregional context emerged as the strongest predictors of distributional change, underscoring the importance of historical and environmental context over simple measures of habitat loss and fragmentation. These results indicate that while long-term LULC change establishes the underlying landscape template, species responses are structured by ecological context, including habitat affinity, taxonomic traits, and regional environmental gradients. By linking historical landscape trajectories to contemporary biodiversity patterns, this study provides a transferable framework for investigating how land-use legacies influence species distributions and community reassembly in heterogeneous human-dominated landscapes, highlighting the importance of adaptive capacity and connectivity for conservation planning.

The concept of "wild" is poorly defined when applied to non-human animals, despite its central role in conservation, wildlife management and environmental policy. Despite numerous attempts to define "wildness", the distinction between "wild" and "non-wild" remains inconsistently applied. A shared, empirically grounded understanding of wildness would strengthen communication, support policy and legislation, and clarify human attitudes towards wildlife and nature. We assessed whether a shared understanding of wildness exists within the research community. A total of 358 professionals from different fields completed an online survey comprising 44 wildness-related statements along established measures of attitude and acceptability toward wildlife (AATW) and nature-relatedness (NRS). . Exploratory Factor Analysis revealed six components (19 statements): Human-mediated animal availability, Urbanisation, Independence from humans, Human-wildlife perceived conflict, Individual history of wildness, and Feralisation. These factors explained 43.91% of the variance. Mediation analysis showed that urbanisation and human-wildlife perceived conflict shape nature-relatedness by influencing attitudes and acceptability towards wildlife. Respondents demographic and professional backgrounds influenced their conceptualisation of wildness. While there is a shared latent structure of wildness across fields, it is multidimensional. This has implications for developing working definitions applicable to research, policy and practice.

The biodiversity crisis is exacerbated by persistent gaps in taxonomic, geographic, and conservation knowledge. This study provides a comprehensive assessment of Linnean, Wallacean, and conservation shortfalls in Rivulidae (Cyprinodontiformes), one of the most diverse families of Neotropical freshwater fishes. To this end, an extensive dataset was compiled, comprising 494 valid species, 51 synonyms, 3,419 occurrence records, and information on life cycle, distribution, and conservation status. The Linnean shortfall remains open: after 1975, the rate of species description increased sharply, and estimates indicate that 103 species remain undescribed (95% CI: 53-212). The year of species description was influenced by detectability and accessibility factors, with larger species, more widely distributed species, and species occurring in more densely populated areas being described earlier. The Wallacean shortfall was broad and spatially uneven: only 5.34% of the region was considered adequately sampled. The conservation shortfall was also substantial: 179 species are threatened with extinction, 69 species remain Not Evaluated, and 62 are Data Deficient. The mean time between taxonomic description and first IUCN extinction-risk assessment was 25.7 years. Moreover, 59.9% of species have no records within protected areas, including 69.3% of threatened species. These findings synthesize an urgent challenge: biodiversity knowledge and conservation shortfalls must be overcome simultaneously to protect species that are still being discovered, remain poorly documented spatially, and are restricted to habitats under intense anthropogenic pressure. The conservation of Rivulidae cannot wait for complete knowledge; action amid uncertainty is necessary to prevent both known and unknown species from disappearing.

Governments, civil society organizations and businesses often lack the biodiversity data they need for decision-making and adaptive management, impacting their planning, reporting and performance. We explored the biodiversity data needs of such actors in Colombia, Ghana and Switzerland to identify factors affecting data availability and use. Responses to questionnaire surveys showed that the data types with the biggest gaps between user needs and access were progress on conservation or sustainability actions, species populations, habitat state and ecological risk. The most frequent data blockages related to inadequate resources and organizational capacity. Obstacles significantly associated with a lack of primary data included an absence of organizational biodiversity goals and monitoring systems. Problems accessing habitat quality and species abundance data were associated with data collection methods being unknown or unavailable. Businesses were more likely than other groups to need data on threats, perhaps reflecting the increasing importance of environmental risk to the corporate sector. Businesses are less likely to collect primary data or use secondary data and are significantly more likely to be unclear on what biodiversity indicators to use. Non-business organizations are significantly more likely to be unable to access data because of a lack of funding for data collection, analysis, and use. Our results highlight the need for stakeholders across sectors to work together to find common solutions to build and invest in monitoring capacity that unblocks the flow of biodiversity data.

ContextThe decline, extirpation and extinction of Australias mammal fauna is without peer. In recent decades long term monitoring has revealed tragic patterns in iconic locations such as Kakadu National Park. AimsPast studies have described universal patterns across multiple national parks in the Northern Territory, linking the declines to fire management; however, much of the data in Nitmiluk National Park do not cover the period that encompasses this decline. We examine this data separately to look for patterns with respect to fire history. MethodsWe examined standardised mammal survey data collected in Nitmiluk from 2005 to 2018, to look for correlates with year of survey, time since last burnt, and the frequency of early season and late season burns. Key resultsDespite subtle difference in methods over the years, we found there were some annual changes in the mammals, but little discernible pattern of change correlated to fire regime (which itself indicated an improvement in seasonality, and the extent of burning overall over this period). Instead, there was a distinct reduction in the survey effort. ConclusionsOur study provides further support for the pitfalls of ecological monitoring losing focus, being decoupled from management actions, and allowing ill-conceived changes in design. We recommend that future monitoring at Nitmiluk should focus on key management questions (i.e., fire), best methods for target taxa (i.e. camera traps), more regular and flexible sampling linked to a conceptual model, and integration and co-design with the local land managers, rangers and Traditional Owners. Short SummaryRe-examination of the mammal data collected in monitoring sites at Nitmiluk National Park between 2005 to 2018 indicated little pattern with fire regime over time, and instead indicated that a reduction in effort, had reduced the ability to find pattern With sparse and declining mammal population in northern Australia, future monitoring needs to be focused on key management questions.

The ongoing decline in biodiversity highlights the need for understanding the causes of population changes. This study uses 25-year, large-scale monitoring dataset to investigate the influence of climate and landscape structure on the annual population growth rates of 84 bird species across Poland. Our methodological framework involves the spatiotemporal decomposition of these environmental drivers to decouple demographic effects of long-term carrying capacities from the short-term effects of environmental perturbations. Using species-specific demographic models followed by a community-wide meta-analysis, we evaluated how individual species responses scale up to shape community-level dynamics. The results reveal significant variation in species-specific responses to individual drivers. At the community level, our findings suggest that bird populations are mainly regulated by the long-term spatial constraints rather than short-term disturbances. Persistent environmental heterogeneity had the strongest positive demographic effect on birds, followed by temperature, forest dominance over croplands, and precipitation. In contrast, rapid temporal shifts in environmental heterogeneity and precipitation anomalies negatively affected population growth, whereas urbanisation consistently exerted a negative effect across both spatiotemporal dimensions. Our results highlight the significance of protecting existing heterogeneous and ecotonal habitats, as well as the need to incorporate features that enhance habitat heterogeneity into urban development. Article impact statementPreserving heterogeneous habitats is essential for the conservation of bird populations.

Resource scarcity prompts animals to adjust their space use in ways that enhance their survival. In wild herbivores, seasonal habitat shifts are well studied; however, little is known about how large herbivores navigate human-dominated landscapes under fluctuating resource conditions. In Hong Kong, feral water buffalo (Bubalus bubalis; henceforth buffalo) experience declines in body condition score during the dry season. While buffalo expand spatial ranges in the dry season, whether this expansion reflects access to improved ecological conditions, and how key anthropogenic factors (like distance to roads and human density) further influence space use, remains understudied. We observed six buffalo herds (n=92 known individuals) across one wet (July-September 2023) and one dry (January-March 2024) season. We recorded herd locations and extracted remotely sensed habitat and environmental data. We used Normalized Difference Vegetation Index (NDVI) as a proxy of vegetation productivity and included elevation, distance to roads, and human density as additional predictors. We hypothesized that dry-season space use would shift toward higher vegetation productivity, and that anthropogenic factors would have weak influence on space use due to the adaption of buffalo in human-dominated landscapes. We found that buffalo used areas with higher vegetation productivity and higher elevation in the dry season than in the wet. Distance to roads and human density had no detectable effect. Our findings reveal that space use by a large herbivore like buffalo in human-dominated landscapes is strategic and resource driven, and that these seasonal shifts may have important implications for local biodiversity and human-animal interactions.

Large-scale annual releases of pheasants Phasianus colchicus and their subsequent management for recreational shooting create various ecological impacts in the UK. While effects at release sites are fairly well understood, dispersing birds may influence areas farther away. If they enter ecologically important but sensitive protected areas (PAs), any negative impacts could be especially harmful. Using tracking data, from 766 birds across 10 sites, we estimated survival and dispersal of released pheasants and applied these patterns to gamebird release records near English PAs to gauge intrusion risk. Of 2,885 registered release sites, just over half lay within 2 km of a PA. A large number of shoots release relatively few birds while a small number release many birds. Thus, numbers expected to enter a particular PA likely depend both on the size of releases and proximity to the PA. We estimate that, at a national level, a maximum of between 525,000 and 784,000 pheasants might be found within PAs very soon after release, representing around 1.7% of all the pheasants released annually. This number declines over the months after release until in February, we estimate that there are between 131,000 and 196,000 pheasants (0.4% of the total release) might be found within PAs. The critical metric by which ecological damage might occur is their density within PAs. Mean densities soon after release averaged 12.0 birds/ha in PAs within 250 m of release sites. This density declined markedly both in time (as birds died) and space (as they moved further from the pen as potential areas increased). By November, densities in PAs 500-1000m from release sites peaked at 0.5 birds/ha, falling to 0.16 birds/ha in February. These estimated densities are around two orders of magnitude lower than those known to cause strong, lasting impacts within release pens. The results are subject to assumptions about movement behaviour, game management and bias in registration. Despite these constraints, considerable local variation exists, with a minority of high-volume release sites very near PAs posing the greatest potential ecological risk.

There is an urgent need to gather data on harvest rates of waterbirds in Europe to assess the sustainability of hunting. Estimates of total waterbird harvest in the United Kingdom (UK) and the relative harvest of different huntable species come from two separate surveys, the Value of Shooting (PACEC 2014) and National Gamebag Census (NGC, Aebischer 2019), and these have been recently used to explore the likelihood of unsustainable harvests of wild waterbirds by UK hunters (Ellis and Cameron 2022; Madden et al., 2025). The reliability of these sustainability estimates depends on how representative the original surveys are of hunter behaviour and success. There are also 1-3 million released game-farm mallard (Anas platyrhynchos) that takes up considerable and unquantified proportions of the UK waterbird harvest. Here we explore uncertainties in the UK winter harvest of wild waterfowl by comparing estimates from the NGC dataset with those from the Crown Estate coastal hunting clubs, and a novel approach using analysis of social-media images (2019/20 to 2023/24). We explore the difference in species-specific harvest with and without the uncertainties in the number of released mallard and the total number of duck harvested in the UK. Waterbird harvest estimates differ markedly depending on the input dataset and whether released mallard are included in the analysis. Confidence intervals of each estimate are inflated by uncertainties in the number of released game-farm mallard contributing to, and the size of that national bag. Estimates extrapolated from social media suggest the national harvest of several species may be considerably larger than the corresponding NGC estimates (e.g. Teal *2.07 and gadwall *11.2), while mallard harvests away from formal shoots represented by NGC are significantly lower (*0.71). Excluding released mallard reduces the statistical estimate of total wild duck harvest by 56-63%, which would have biologically significant effects if realised.

Connectivity is critical to sustaining endangered carnivores in speciose yet fragmented landscapes such as in the global south. Corridors to mitigate fragmentation are designed based on charismatic species or habitat-based approaches, but their multispecies effectiveness for maintaining functional connectivity remains poorly tested. We combined landscape genetic analyses across five sympatric carnivores - Panthera tigris, Panthera pardus, Prionailurus viverrinus, Felis chaus, and Melursus ursinus, to evaluate how landscape features shape functional connectivity in a globally important felid landscape. We then assessed the efficiency of existing tiger corridors and single-species surrogates for maintaining multispecies functional connectivity. Species exhibited contrasting responses to landscape variables, producing distinct resistance surfaces and connectivity corridors. Spatial similarity of connectivity between species pairs was highly variable (r = 0.14-0.93), but no single species effectively captured connectivity patterns of the broader carnivore community (maximum mean overlap of <0.7 across species). Moreover, genetically optimized corridors were at least 70% more efficient in capturing connectivity compared to existing tiger corridors, demonstrating mismatches between structural and functional connectivity. Our results highlight limitations of surrogate-based corridor planning and demonstrate that integrating multispecies functional connectivity can substantially improve conservation planning in human-dominated landscapes.

Accelerating global urbanization necessitates a better understanding of how to manage cities that promote biodiversity. However, we currently lack multi-year, multi-city studies, which limits a generalizable understanding of how both within and between city differences impact the spatial and temporal dynamics of urban biodiversity. Here, we tested hypotheses about the drivers of butterfly diversity within and across urban parks by applying Bayesian occupancy models to five years of iNaturalist community science data from 2,550 parks in 22 major U.S. cities. We found that cities with bigger parks supported more species per park, including more disturbance- and edge-avoidant species. This was driven by a positive effect of park size on butterfly species colonization rates. We also found that attributes of habitat quality (plant diversity within parks and tree cover surrounding parks) contributed to butterfly species occupancy. Park connectivity increased species persistence, but the overall effects on butterfly species occupancy varied across cities. Finally, we found that the total area of tree cover throughout a city, rather than the size or connectivity of individual parks, was the primary determinant of city-wide diversity: Increasing total tree canopy cover from below-average (~6%) to above-average (~22%) increased city-wide species richness by ~10%. These findings highlight the need for cities to maintain large parks while also increasing city-wide tree cover to support biodiversity across local to regional scales. By integrating high-resolution community science data across the continental U.S., this study provides mechanistic insight into how cross-scale processes shape urban biodiversity dynamics and identifies generalizable recommendations for improving urban conservation management.