Conservation Letters

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.

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.

Management of marine protected areas (MPAs) require long-term monitoring and evaluation that is often limited by the cost and effort of conventional visual based surveys. We evaluated a community science-based eDNA approach to MPA monitoring over two years in the Point Dume State Marine Reserve, the Point Dume State Marine Conservation Area, and two paired unprotected reference sites. Across the sampling period, we detected 119 species of fish and marine mammals, including 19 of the 22 regional management-priority species for Southern CA MPAs. Protected and unprotected comparison sites were broadly similar in overall assemblage with 93 species shared across all sites. Multivariate analyses revealed site-level differences, although season and year explained more variation than protection status. Species presence also shifted during a La-Nina transition, highlighting the importance of long-term monitoring under different climatological contexts. Community scientists greatly expanded the temporal and spatial scope of eDNA sampling and generated high-quality data. Subsampling analysis showed that quarterly sampling, with three sample replicates and sequencing depths between 700k-990k, recovered 95% of observed biodiversity of the full time series. These results demonstrate that a community science-based eDNA program could provide a standardized, scalable, low-cost, and management-relevant approach for long-term monitoring across California's MPA network.

BACKGROUND: The Argentine ant (Linepithema humile) is among the world's worst invasive species. In the Donana Biological Reserve (Spain), it is associated with human structures that provide the mild, moist conditions it needs within the hot, dry scrubland. We evaluated a habitat-modification treatment, predicting that removing this suitable habitat would eradicate the invader locally. Over an 18-year period, we monitored ant communities at a treated and an untreated site, at different distances from the human structures, before and after treatment, and analysed how temperature and worker numbers affected encounters at baits between the Argentine ant and native ants. RESULTS: Distance to the human structures shaped ant communities at both sites, but only the treated site changed after treatment. There, the Argentine ant decreased close to the human structure and almost disappeared farther from it, whereas the endemic Cataglyphis tartessica and C. floricola recovered, especially close to the structure. At baits, the outcome of encounters depended mainly on how temperature changes favoured each species relative to its maximum activity temperature: Cataglyphis spp. displaced the Argentine ant in the morning, as temperature increased, and the Argentine ant recovered the baits in the late afternoon. Numerical advantage favoured only the Argentine ant. CONCLUSION: Habitat modification reduced the Argentine ant and allowed endemic ants to recover, but did not eradicate the invader, which persisted at low abundance 13 years after treatment. In protected areas, habitat management should be combined with eradication, monitoring and prevention of spread.

Human-wildlife conflicts over shared resources are often interpreted as direct competition, whereby resources consumed by wildlife are unavailable to people. Yet, individuals of wild populations can differ in their propensity to exploit resources, and the demographic, ecological, and economic consequences of such behavioural heterogeneity remain poorly understood. We developed an integrated demographic-bioeconomic model of Atlantic cod (Gadus morhua), grey seals (Halichoerus grypus), and a coastal gillnet fishery. Stage-structured population models incorporated density dependence, predator-prey interactions, adaptive harvesting, and transitions of adult seals into a bold, depredating state. We compared four scenarios of increasing complexity over 50 years across 100 coupled demographic realisations and examined sensitivity to the energetic contribution of depredated catch, harvest levels, and social amplification of depredation behaviour. Cod and seals persisted in all demographic realisations, supporting our ecological-persistence hypothesis. Contrary to our predictions, however, adding bold seals neither reduced long-term fishery performance nor destabilised the system. Median net present value was approximately three-fold greater in the full system than without depredation, and was greater in 76% of paired realisations. The full system was also the most temporally stable: median cod variability declined by 74% relative to the otherwise equivalent fishery without depredation, while seal variability declined by 45%. Behavioural depredation therefore altered predator population structure and imposed direct catch losses, but these effects were counterbalanced by indirect demographic feedbacks. Synthesis and applications. Depredating predators should not necessarily be viewed simply as competitors that reduce contested resources. Behavioural heterogeneity can introduce compensatory pathways that alter population stability and long-term economic outcomes. Management should therefore consider not only predator abundance and immediate catch losses, but also how harvest creates opportunities for behavioural change and how those changes propagate through coupled ecological-economic systems.

Over the past two decades, significant population recoveries of tigers and leopards have driven a substantial rise in human-carnivore conflict across South Asia. Sustaining the long-term conservation of both species demands effective, adaptive conflict management. However, existing research is largely confined to isolated landscapes or protected areas, hindering the identification of spatial conflict drivers across broader, heterogeneous regions. To address this gap, this study compiled 4,457 human leopard conflict (HLC) and 2,563 human tiger conflict (HTC) records spanning 2000 to 2024 across Bangladesh, Bhutan, India, and Nepal. We evaluated conflict locations against 33 landscape, anthropogenic, climatic, topographic, and hydrological predictors across three spatial scales using binomial generalized linear regression models and three alternative background sampling methods. Model performance peaked at the largest spatial scale for both species and remained consistent across sampling strategies. HTC correlated positively with forest fragmentation and proximity to human settlements, but decreased with higher overall anthropogenic disturbance. Conversely, HLC concentrated in highly productive, high-precipitation, human-modified landscapes. These contrasting spatial patterns highlight distinct ecological responses to habitat modification and carry unique conservation implications. Ultimately, this study underscores the need to integrate carnivore abundance, wild prey densities, and socioeconomic factors to achieve a holistic understanding of conflict dynamics.

The increased frequency and intensity of coral bleaching events expose reefs to disturbance-recovery cycles that threaten their long-term dynamics. Understanding the impact of thermal stress requires evaluating coral mortality and recovery rates after disturbances. By integrating two long-term monitoring datasets, we examined coral mortality and recovery patterns at 13 sites in Mo'orea, French Polynesia, following the 2019 bleaching event, the most severe heat stress on record for the island. The maximum accumulated heat stress (AHSmax) varied from 5.76 to 6.26 {degrees} C weeks and enabled a direct analysis of heat-stress-related mortality. One year after bleaching, Pocillopora mortality increased with AHSmax, reducing mean coral cover from 35% to 17%. Regardless of AHSmax, Acropora mortality was high at all sites (median: 84%), reducing mean cover from 5% to 1% and indicating greater heat tolerance of Pocillopora than Acropora. Within four years after the bleaching event, no recovery occurred, and coral cover further declined relative to pre-bleaching levels. This decline was stronger for sites exposed to more intense heat stress. The impact of colony size was assessed by tracking 3090 individual Pocillopora colonies over six years and estimating size-dependent mortality and growth with a Bayesian mixed model. Immediately after the bleaching event, large Pocillopora corals exhibited a higher probability of complete and partial mortality than smaller colonies, highlighting size-specific consequences of bleaching. Even three years after the heat stress ended, large Pocillopora corals remained stressed, as evidenced by the continuously high probability of partial mortality. The lack of recovery observed here may be related to increased spatial competition with macroalgae. The disappearance of large fecund colonies and high mortality of coral recruits could have catastrophic consequences for the resilience of Mo'orea's reefs.

1. Protecting and restoring corals is critical to conserve marine biodiversity and ecosystem services in the Anthropocene. Knowledge of coral larval dispersal dynamics can be used to identify important sites for coral metapopulation connectivity and to spatially optimise coral conservation efforts. However, we know little regarding the larval dispersal of many coral species and our understanding of the relationships between coral larval dispersal and life-history traits (e.g., reproductive mode, colony morphology), phylogenetic relationships, and biogeography is incomplete. These knowledge gaps impede coral conservation. 2. In this research, we systematically reviewed the species, regions, and methodologies of studies of coral larval dispersal. Additionally, we conducted a meta-analysis to quantify the heterogeneity in reported coral larval duration values and identified the roles of life-history traits in driving that heterogeneity. 3. We found that various methods (experimental, biophysical modelling, and population genetics) were used to study 221 coral species across many regions. Soft and temperate corals received comparatively lower research attention. Our meta-analysis reveals that reproductive mode and colony morphology explain significant heterogeneity in larval settlement times, and that closely-related species have more similar larval settlement times. 4. Our findings suggest that reproductive mode and colony morphology could be used to predict larval duration in under-studied coral species, and that larval duration could be approximated from closely-related corals when trait data is unavailable. Our results support strategies focused on modelling differing larval durations across corals with different life-history traits to predict realised dispersal in under-studied coral species and identify conservation priority sites.

The Peruvian anchovy (Engraulis ringens) is a small pelagic fish. It is the largest singlespecies fishery in the world and it is used mainly for the production of fishmeal and fish oil. The Peruvian hake (Merluccius gayi) is a predatory demersal fish that is valued for direct human consumption, mainly as frozen products. In this study, I compared the response of both species to certain fishing mortality scenarios using a climatological set-up of the multispecies model OSMOSE for the northern Humboldt Current System. I observed that hake landings benefit from a decreased fishing pressure. In addition, the resilience of the anchovy fishery may increase if a higher threshold for their minimum catch size was implemented. The results of this study provide insights into better management strategies that could be beneficial for the two species based on their life-strategies.

Climate change will alter habitat suitability for plant communities in mountain ecosystems of the Western Himalaya. There will be contrasting magnitudes and spatial configurations of these changes for different plant species, and it is an important question how to translate these contrasts into effective climate-proof multi-species conservation planning. This study assessed current habitat associations and projected changes in suitable habitat for two contrasting species, Meconopsis aculeata and Rhododendron campanulatum, in Himachal Pradesh, India. Field surveys and spatially filtered occurrence records were combined with MaxEnt modelling using 10 non-collinear environmental predictors. Habitat suitability was projected to 2050 and 2070 under Shared Socioeconomic Pathways; SSP1-2.6, SSP2-4.5 and SSP5-8.5 using HadGEM3-GC31-LL. Field observations showed contrasting habitat associations, with M. aculeata occurring mainly in open alpine herbaceous communities and R. campanulatum in subalpine woody communities. Elevation was an important predictor for both species while climatic predictors contributed differently to their relative importance and response patterns. Future projections indicated reductions in suitable habitat of approximately 25% for M. aculeata and 27-28% for R. campanulatum. Habitat-change maps showed heterogeneous patterns of loss, gain and persistence rather than uniform contraction, and centroid displacement remained small (7.7-8.5 km). We performed proximity analyses to show which currently suitable areas are most close to areas of future gain, in order to support the design of climate-proof protected areas. We discuss how interspecific differences in response are relevant to multi-species conservation planning that considers the spatial relationship between current high-suitability areas and the gain, loss and redistribution of future suitable habitat.

Climate change poses a major threat to marine mammal populations, many of which remain vulnerable after years of overexploitation during the 17th to 20th centuries. Extreme climate events have grown in both frequency and severity in recent decades, and this trend is projected to accelerate under continued greenhouse gas emissions. Here, we assess how this intensification affects a top marine predator at the epicentre of extreme El Nino events - the Peruvian population of Otaria byronia (South American sea lion). We first apply a Bayesian population model that best predicts observed population dynamics to reconstruct female O. byronia population trends, estimate vital rates, and evaluate the effects of environmental drivers on survival and reproduction. We then use the same model to project extirpation risk under multiple future climate scenarios reflecting anticipated increases in both the intensity and frequency of extreme El Nino events. Our reconstruction reveals that the Peruvian O. byronia population has shown considerable resilience to episodic El Nino events over the past quarter-century, likely sustained by high female survival during normal and favourable years. However, under a scenario of moderate increases in El Nino frequency and intensity, the probability of extirpation over the next 50 years is 83.4% higher than under current conditions. As disturbance regimes intensify globally, we suggest that resilience-oriented management frameworks, grounded in species-specific demographic data and environmental context, as demonstrated here, will be essential for safeguarding marine mammal populations against an increasingly volatile climate.

Reef fish assemblages in the Veracruz Reef System National Park (VRSNP) are strongly structured along a pronounced north-south gradient, where environmental conditions, urban proximity, and protection levels interact to shape functional diversity and ecosystem functioning. This gradient creates contrasting ecological conditions between northern and southern reefs, providing a natural framework for evaluating how spatial variation influences resilience. Using a stationary visual census across ten reefs distributed latitudinally, we quantified functional entities based on six ecological traits and calculated functional richness, redundancy, over-redundancy, vulnerability, specialization, and originality. A two-way permutational ANOVA and redundancy analysis were used to detect spatial and temporal patterns and to link functional indices with environmental features. The southern sector displayed the most intense functional shifts. Nearshore southern reefs, strongly exposed to sedimentation, nutrient loading, and physical disturbance, exhibited reduced functional richness, fewer functional entities, and high functional vulnerability, indicating strong environmental filtering. Over time, these reefs shifted toward generalist-dominated assemblages with rising redundancy, suggesting functional convergence. In contrast, southern offshore reefs supported higher taxonomic and functional richness, buffered by greater habitat complexity and distance from shore, although they showed declining redundancy, likely reflecting sensitivity to regional climatic disturbances. In the northern sector, the gradient was moderated by effective protection, which reshaped functional configurations. Nearshore protected reefs such as Isla Sacrificios and Isla de Enmedio maintained high redundancy, low vulnerability, and high biomass of large-bodied fishes, resembling offshore systems rather than disturbed southern nearshore reefs. The northern offshore reef (Isla Verde) shared some of these attributes but exhibited temporal declines in richness, signaling emerging vulnerabilities along the gradient. Functional originality and specialization aligned with benthic states across the gradient, particularly where macroalgal or calcareous substrates prevailed. Overall, the north-south gradient is the primary axis of functional organization in VRSNP, revealing that resilience emerges from the interplay among reef geomorphology, urban influence, and governance effectiveness.

Information on the long-term dynamics of species distributions is essential for assessing global biodiversity change and its causes, and for informed conservation decisions. A valuable source of such historical information are atlases. They provide spatial standardisation, extensive geographic coverage, temporal replication, documented sampling protocols, and span multiple species. Here we present model-based occupancy probabilities for 1,055 bird and 58 butterfly species, derived from nine gridded atlas datasets spanning several editions over the past 50 years. These are: Japan, New Zealand, New York state (US), the states of Alberta, Quebec, and The Maritimes (Canada), Czech Republic, United Kingdom, and Europe. Despite standardisation and coordination during data collection, the raw atlas data still contain some variation in sampling effort. We accounted for this using a two-step process: (1) we estimated a proxy for sampling effort in each grid cell within each atlas period using the Frescalo Algorithm, and (2) we ran a Bayesian spatial occupancy model for each species and atlas period, using the estimated sampling effort as the single predictor of detection in the observation process of the model. As the main product, we provide occupancy probabilities for species across grid cells and atlas periods. We also report uncertainty around each probability estimate and flag ~21% (rare) species per atlas for which the model did not fit well. The probability distributions are fit for purpose and served in a user-friendly database with standardised geographic projection, metadata, and taxonomy.

Despite the popularity of carbon credits as a tool to offset greenhouse gas emissions, there are growing concerns over whether their climate mitigation claims are robust. Most attention has focused on natural risks to forest carbon projects, such as wildfire, while social risks (e.g., those driven by fraud, mismanagement, and land conflicts) remain largely unquantified. Here we analyze 244 forest-based carbon projects to assess the vulnerability of the voluntary carbon market to social risks and find that projects systematically underestimate their risk of failure. Even under optimistic assumptions, projects are roughly twice as likely to fail within 25 years as their self-assessed risk implies over a 100-year horizon. Projecting these trends forward, we show that credits issued to failed projects could exceed the reserves registries hold to mitigate these risks within 1-2 decades. Overall, our results suggest stronger mechanisms and reserves are needed to ensure carbon credits deliver the promised climate benefits.

This study examined the spatial distribution of potential human encounters with dangerous large mammals in and adjacent to the Ifakara-Lupiro-Mang'ula Wildlife Management Area (ILUMA WMA) and Nyerere National Park (NNP) in southern Tanzania. Using published survey data collected over one year, this secondary analysis focused on four potentially dangerous large mammals: elephant (Loxodonta africana), buffalo (Syncerus caffer), hippopotamus (Hippopotamus amphibius) and hyena (Crocuta crocuta). Potential encounter risk was estimated using overlap indices based on co-occurrence of signs of wildlife and human activities. Potential encounter risk was found to be concentrated around readily identifiable foci within the study area and differed between species and distinguishable human livelihood activities. Potential for encountering the two most apparently important dangerous animals, elephant and buffalo, was closely associated with authorized fishing camps within the ILUMA WMA and the ecotone between substantially disturbed and largely intact natural land cover. The greatest potential for encountering hippopotamus occurred largely around two river beds, while hyena encounter potential was more closely associated with established villages and converted lands close to the western boundary of the ILUMA WMA. These new maps of hazard and risk suggest that effective human-wildlife conflict (HWC) mitigation in this WMA is unlikely to arise from any stand-alone intervention, but from targeted actions that reduce spatiotemporal overlap between people and wildlife by keeping them apart and/or protecting them against each other. Overall, this study demonstrates that mapping potential encounter risk based on spatiotemporal overlap of indirect activity indicators like tracks, spoor and signs provides a proactive and statistically powerful way to identify where hazardous encounters are most likely to occur, offering considerable advantages over retrospective assessments of much sparser observations of actual realised conflict events after they have already occurred. This new spatial risk mapping approach provides a framework for shifting management from reactive responses after conflict occurs towards proactive prevention.

Global biodiversity loss is a consequence of habitat degradation and fragmentation caused by the expansion of the Anthropocene and the overexploitation of natural resources. Passive acoustic monitoring enables longitudinal assessment of biodiversity but generates massive datasets. Advancements in machine learning have enabled the development of convolutional neural networks capable of automating this process. We developed a lightweight 2D convolutional neural network capable of detecting echolocation calls of the greater sac-winged bat, Saccopteryx bilineata, an insectivorous aerial edge-foraging bat, across a tropical restoration gradient in Para, Brazil. The 2D-CNN model achieved a 97.84% accuracy and 100% precision. Deploying this model across 157,335 field recordings across 29 sampling points resampled over 3 years (2023-2025) yielded 2,098 positive detections of S. bilineata. Generalised linear mixed models revealed that time since reforestation significantly increased the odds of detecting S. bilineata ({beta} = 0.22, p < 0.001), and that detection probability was 2.14 times higher in restoration plots than in forest habitats ({beta} = 0.76, p = 0.0701). Acoustic hardware had a significant covariate influence in both fitted models ({beta} = 0.52, {beta} = 0.72, both p < 0.001). These findings demonstrate the practical applications of deep learning and bioacoustics to quantify habitat recovery and the value of restoration in regenerating functional ecological niches for aerial insectivores during early successional stages.

The identification and use of stress-tolerant coral in outplanting efforts has been proposed as a method of restoring and bolstering reef health under increasing environmental change. Prior research has focused on understanding survival in cross-reef transplantation, but evidence of long term resiliency of outplanted corals remains limited. Here, we report data at a five-year timepoint of a reciprocal transplant study of the stress-tolerant Caribbean corals Pseudodiploria strigosa and Siderastrea siderea between a nearshore and offshore site in Belize. Extreme marine heat wave conditions in August of 2024 revealed species and site-specific bleaching patterns. Through assessments of mortality, energy reserves, and chlorophyll concentrations, P. strigosa appear to be more limited in long-term acclimatization potential to the nearshore environment while S. siderea maintain acclimatization capacity displayed 17 months post transplant to nearshore. This work conveys information relevant to managers in selecting species for restoration efforts based on short-term growth and long-term resilience in native versus non-native sites, offers insight into potential mechanisms driving these trends, and takeaways on site specific management decisions for successful coral outplanting success.

Coral skeletal integrity underpins reef habitat complexity and coastal protection, yet it remains unclear whether corals persisting in chemically variable marginal habitats, such as mangrove-associated reefs, maintain sufficient mechanical resistance to withstand physical disturbance. We combined micro-computed tomography (micro-CT) morphometric analysis with compression testing to quantify skeletal microarchitecture and compressive mechanical performance of Pocillopora sp. skeletons collected across a habitat gradient at Low Isles, Great Barrier Reef, from mangrove-associated sites to exposed reef sites. Baseline skeletal properties varied among sites, with the Proximal Reef site having the densest and least porous skeletons, while mangrove-associated sites had the most porous skeletons. Similarly, Proximal Reef skeletons exhibited two-to-three-fold greater compressive stiffness and peak force than mangrove-associated skeletons. Percentage object volume was a stronger predictor of compressive stiffness than surface area-to-volume (S/V) ratio, indicating that bulk skeletal density better captured load-bearing capacity than surface architectural complexity. Structural failure mode also differed markedly among habitats: mangrove-associated skeletons underwent catastrophic fragmentation of their open, porous framework, whereas Distal and Proximal Reef skeletons failed through discrete crack-plane propagation while largely maintaining overall structural coherence. These results indicate that the physiological stress tolerance associated with mangrove habitats occurs alongside reduced mechanical resistance and more destructive failure modes, suggesting a potential trade-off between chemical stress tolerance and structural investment. Assessments of resilience in marginal coral populations should therefore consider skeletal mechanical performance alongside physiological tolerance, particularly as climate change intensifies storms and alters hydrodynamic disturbance regimes.

Extreme climate events are rapidly reshaping ecosystems and contributing to biodiversity loss, yet their long-term impacts remain poorly understood, particularly in marine systems. In 2011, an unprecedented marine heatwave (MHW) on the west coast of Australia drove declines in habitat-forming plants and across taxa spanning multiple trophic levels. Shark Bay, home to an iconic Indo-Pacific bottlenose dolphin (Tursiops aduncus) population, endured temperatures 3-5{degrees}C above long-term means, triggering catastrophic seagrass loss. Using 20 years (2003-2023) of dolphin photo-identification data, we fitted a Bayesian Hidden Markov Model to estimate annual, age-class specific survival probabilities, abundance and recruitment rate, and their association with MHW-mediated seagrass loss in the western (WSB) and eastern (ESB) gulfs of Shark Bay. Adult survival declined markedly, from 0.99 (0.98-1.00) pre-MHW to 0.85 (0.79-0.90) post-MHW in WSB, and from 0.96 (0.92-0.98) to 0.89 (0.85-0.95) in ESB, remaining below pre-MHW levels for several years, while juvenile and calf survival declined in both gulfs to a lesser extent. Recruitment declined in both gulfs and, although recovery was evident in WSB from 2019 onward, continued to decline in ESB until the end of the study. These sustained demographic declines drove substantial reductions in population growth and abundance in both WSB (39%) and ESB (36%). Demographic changes were associated with seagrass loss, here a proxy for habitat and prey availability, with clearest support for adult survival in WSB and a two-year-lagged recruitment response in ESB. This pathway is likely to operate across diverse ecosystems as climate change drives increasing loss of habitat-forming species. The severity and duration of these demographic impacts illustrate that habitat change can cascade through trophic systems to overwhelm demographic resilience in upper-trophic species. This has negative implications for even long-lived, K-selected species, whose slow demographic recovery may not keep pace with the accelerating frequency and intensity of climate disturbance.