Animal Conservation

In long-lived species, logistical constraints often limit monitoring to adult population censuses, potentially generating data that is biased towards older, more discernible individuals, and obscuring problems occurring at early life stages. Since adult populations of long-lived species can persist for decades despite reduced productivity, declines driven by reproductive failure may remain undetected until sudden population collapses occur. We present preliminary data on fertilisation success, early embryo survival, and hatching success, across one natural and five translocated populations of Aldabra giant tortoises (Aldabrachelys gigantea) in the Seychelles. Of 317 eggs from 24 clutches, only 16% successfully hatched. Most failed eggs (97%) were undeveloped, and using recently developed microscopic methods to assess egg fertility, we provide the first population-level comparisons of fertilisation and hatching outcomes for this species. Although sample sizes are limited, our results consistently indicate low and variable hatching success across populations, driven primarily by embryo mortality. Complete clutch failure was common (67%), and among clutches that did experience some degree of hatching success, early embryo mortality was still prevalent. Hatching rates were markedly reduced in translocated populations (0-26%) compared to the natural Aldabra Atoll population (46%) and consistently fell below historical hatching rate estimates (60-80%) reported [~]50 years ago. Although preliminary, these data provide the most accurate estimates of fertility available for Aldabra giant tortoises, as well as the first reproductive success data for any translocated population and the first for Aldabra in the last five decades. Our findings highlight the limitations of relying solely on adult census data for threat assessments in long-lived species. We argue that it is essential to incorporate productivity metrics into monitoring frameworks to improve population vulnerability predictions and inform effective conservation management.

Due to climate change and habitat conversion, estimates of the number of species extinctions over the next century are alarming. Coming up with solutions for conservation will require many different approaches, including exploring the extinction processes of recently extinct species. Given that parrots are the most threatened group of birds, information regarding parrot extinction is especially pressing. While most recent parrot extinctions have been island endemics, the Carolina parakeet (Conuropsis carolinensis) had an 18th-century range covering nearly half of the present-day United States, despite which, they went extinct in the 20th century. The major cause of their extinction remains unknown. As a first step to determining what caused their extinction, we used a newly published, extensive dataset of Carolina parakeet observations combined with a Bayesian extinction estimating model to determine the most likely date of their extinction. By considering each of the two subspecies independently, we found that they went extinct ~30 years apart: the western subspecies (C. c. ludovicianus) around 1914 and the eastern subspecies (C. c. carolinensis) either in the late 1930s or mid-1940s. Had we only considered all observations together, this pattern would have been obscured, missing a major clue to the Carolina parakeets extinction. Since the Carolina parakeet was a wide-ranging species that went extinct during a period of rapid agricultural and industrial expansion, conditions that mirror those presently occurring in many parts of the world where parrot diversity is highest, any lessons we can glean from their disappearance may be vital to modern parrot conservation efforts.

The long-standing misconception that the Galapagos petrel (Pterodroma phaeopygia) and the Hawaiian petrel (Pterodroma sandwichensis) were conspecific masked the severe vulnerability of the Galapagos population. By the time its distinct status was recognized, the Galapagos petrel was already in marked decline, primarily due to invasive predators. Consequently, sustained rodent control programs have been implemented on Santa Cruz Island. An unintentional one-year failure in rodent control provided a rare quasi-experimental opportunity to quantify the demographic consequences of the invasive black rat predator. During this year, hatching success declined by [~]35% and breeding success by [~]40% relative to long-term means (66% and 62%, respectively), representing a substantial reproductive collapse. Fledging success exhibited a comparatively modest decline (from a long-term mean of 94% to 86% in 2017), suggesting stage-specific vulnerability. These results support the hypothesis that invasive black rats primarily affect early reproductive stages through egg predation and predation on small chicks, while older chicks surpass a critical size threshold that reduces susceptibility. Across the remaining managed years, reproductive metrics exhibited great stability, demonstrating the petrels resilience against other environmental or climatic stressors. Our findings provide robust empirical evidence that invasive rodent control is the dominant driver of reproductive success in this endangered seabird. The quasi-experimental failure underscored both the effectiveness and the necessity of continuous predator management, highlighting the severe and immediate consequences of even short-term lapses.

The amphibian endemic fauna from Madagascar is currently facing multiple threats, including habitat loss, climate change and invasive species. Many species are listed as threatened by the IUCN, but long-term monitoring is scarce and assessments rarely account for population trends. Using a 13-year amphibian survey in the Strict Nature Reserve of Betampona (eastern Madagascar), we assessed the population trends of 38 species between 2010 and 2022 based on amphibian activity. Despite the high protecction status of the reserve, we found a negative trend for 15 species, a positive trend for 13 species increasing and 13 species with no significant trend detected. We propose to update the status of 15 species towards a threatened category (CR, EN, VU). Contrasting population trends in amphibians from Betampona might modify species composition and ecosystem functions in the future. This study highlights an important underestimation of extinction risks for a large proportion of amphibians from Madagascar, and more generally in the tropics where long-term population trends are poorly documented.

The Mammal Diversity Database (MDD) is an open-access resource providing up-to-date taxonomic, nomenclatural, and geographic data for global mammal species. Since its launch in 2018, the MDD has transformed the traditionally static process of updating mammalian taxonomy into regular online releases reflecting the latest published research. To build on this foundation, we here present version 2.0 of the MDD (MDD2), which catalogues 6,759 living and recently extinct mammal species, representing net increases of 4.1% and 24.8% over MDD version 1.0 and Mammal Species of the World, 3rd edition (MSW3), respectively. Additionally, we identify a net increase of 68.8% (+2,754; 3,149 splits + de novo, 395 lumps) species since 1980 at a rate of [~]65 species/year based on past totals from 14 mammalian compendia, leading to projections of [~]7,084 species by 2030 and [~]8,382 by 2050 if these trends continue. Key updates in MDD2 include: (i) codings of US state, country, continent, and biogeographic realm geographic categories for each species; (ii) a comprehensive nomenclatural dataset for 50,230 valid and synonymous species-rank names, curated with type locality and specimen information for the first time; and (iii) integration between the MDD and the databases Hesperomys and Batnames for greater data accuracy and completeness. These updates bridge critical gaps in the taxonomic and nomenclatural information needed for ongoing revisions and assessments of mammalian species diversity. Using these data, we evaluate temporal and geographic trends over the past 267 years, identifying four major time periods of change in mammalian taxonomy and nomenclature: (i) the initial monographic description of traditionally charismatic species (1758-1880); (ii) the peak of descriptive taxonomy, describing subspecies, and publishing in journals (1881-1939); (iii) the shift toward revisionary taxonomy and polytypic species (1940- 1999); and (iv) the current technology-driven period of integrative revisionary taxonomy (2000- present). Geographically, new species recognition since MSW3 has been concentrated in equatorial, mountainous, and island regions, highlighting areas of high mammal endemism (e.g., Madagascar, Philippines, Andes, East Africa, Himalayas, Atlantic Forests). However, gaps in 21st century taxonomic activity are identified in West and Central Africa, India, and some parts of Indonesia. Currently lagging conservation assessments are alarming, with 25% of the MDD2-recognized mammal species allocated to the understudied conservation threat categories of Data Deficient (11%) or Not Evaluated (14%), underscoring the need for greater taxonomic integration with conservation organizations. Governance advancements in MDD2 include the establishment of external taxonomic subcommittees to guide data collection and curation, a rewritten website that improves access and scalability, a cross-platform application that provides offline access, and new partnerships to continue linking MDD data to global biodiversity infrastructure. By providing up-to-date mammalian taxonomic and nomenclatural data--including links to the text of original name descriptions, type localities, and type specimen collections--the MDD provides an integrative resource for mammalogists and conservationists to more easily track the status of their study organisms. Teaser Text: The Mammal Diversity Database 2.0, listing 6,759 mammal species and 50,230 species-level synonyms, unifies 267 years of taxonomic, nomenclatural, and geographic data to track global mammal biodiversity and provide a continually updated resource for the mammalogical community. Teaser Image: Figure 3. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=117 SRC="FIGDIR/small/640393v1_fig3.gif" ALT="Figure 3"> View larger version (34K): org.highwire.dtl.DTLVardef@1012e67org.highwire.dtl.DTLVardef@8d99d7org.highwire.dtl.DTLVardef@6f21b9org.highwire.dtl.DTLVardef@f23fd_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOFigure 3.C_FLOATNO Type locality locations for species-rank mammal taxa described from 1 January 2000 to 15 August 2024. Map gray-scale country coloration represents the total number of currently valid species type localities found per country described within this period. Colored dots represent the exact georeferenced type locality of all currently valid species (red circles) and names currently considered synonyms and subspecies (blue diamonds) in MDD2. Most coordinates were generated from the original description of each name when included directly in publication, while others were georeferenced using GeoLocate or WikiMedia GeoHack place coordinates when not included in the original description publication. The georeferenced localities were mapped and both programmatically and visually vetted for accuracy. Latitude and longitude in decimal degrees is included for each of the names mapped here in the MDD2 synonym list, Supplementary Data SD2. C_FIG

The mammal fauna in many parts of northern Australia has undergone dramatic changes in the past 20-30 years, though longitudinal data that spans this period are limited and largely from coastal and high rainfall regions. We examined data from Judbarra-Gregory National Park that has been collected in a generally systematic manner from 1986 to 2015. We standardised this data in a simple manner (i.e., species by relative abundance and site frequency) to examine if there were any stark changes over this time span. Though we recognise some limitations in our comparisons (i.e., spatial variation in sites and methods), the data indicated that the mammal fauna had generally not changed substantially in composition, relative abundance or frequency across sites. However, some species symptomatic of small mammal decline elsewhere (i.e., Rattus tunneyi) may have become less common, whereas other species were recorded for the first time in more recent years (2010-2017), particularly by camera traps (i.e., Trichosurus vulpecula, Isoodon macrourus, Melomys burtoni). We postulate that change in the mammal fauna on the semi-arid fringe of tropical savannas may have occurred prior to the 1980s, with a long history of cattle grazing likely a contributing factor. The mammal fauna there, is also perhaps naturally sparse, and heterogeneous in spatial and temporal distribution.

We combined questionnaires collecting local ecological knowledge with passive and directed camera trapping and bird surveys to scientifically document the Black-Naped Pheasant-Pigeon Otidiphaps insularis for the first time since 1896. This species is endemic to Fergusson Island, in eastern Papua New Guinea, and is New Guineas most endangered terrestrial bird species. Indigenous subsistence-based hunters who participated in this research as informants had high levels of local bird knowledge and helped direct camera trapping for one of two successful camera trap captures. Local participants also shared traditional ecological knowledge about the Black-Naped Pheasant-Pigeon, including legends, chants, and a local name for this taxon, Auwo. The scarcity of observations over the course of a month-long expedition, its obscurity to the majority of local respondents interviewed, and prevalent threats from habitat destruction and introduced alien species further support its current Red List status (CR). Our results provide a case study for leveraging local ecological knowledge in combination with standardized survey techniques and may be an especially effective strategy for determining the status of other undocumented or data-deficient species in the southwest Pacific.

Many alien species are safe in their native ranges; however, some are threatened, posing a challenging conundrum for conservation and invasion science. We focused on alien threatened mammals, examining their distribution, pathways, threats, and conservation strategies. We also reassessed their IUCN Red List category to evaluate the effect of including alien populations in extinction risk assessments. Of 242 alien mammals, we identified 41 aliens that are threatened, classified as critically endangered (19%), endangered (27%), or vulnerable (54%). They were primarily introduced for hunting and exchanged within Asia, with introduced ranges concentrated in eastern Australia. They were subject to multiple threats, most notably biological resource use. Including alien populations in the categorization assessments reduces extinction risk of 22% of the species. We highlighted the conservation value of alien populations for threatened mammals. However, conservation managers and extinction risk assessors shall carefully consider their use, to avoid negative impacts on native biodiversity.

Like many bird species associated with agricultural habitats in the UK, the Twite Linaria flavirostris has undergone severe declines over recent decades due to habitat degradation, with populations in England, Wales and Ireland now restricted to a few small pockets. However, the demographic drivers of these declines are still largely unresolved. We estimated the survival of Twite from a small population at the southernmost edge of the English range in Derbyshire using capture-mark-recapture data from 2016-2019. Annual apparent survival for juveniles (0.14-0.34) was lower than for adults (0.29-0.56) and less than that of other Cardueline finches. Our results suggest that low juvenile survival may be one demographic driver underpinning the recent decline of the Derbyshire Twite population, although we also cannot rule out the possibility that differences in emigration of juveniles and adults from the population also contribute to the observed age-specific apparent survival rates.

Romania represents one of the few European Union member states in which all four Old World vulture species historically maintained breeding populations: the Griffon Vulture (Gyps fulvus), Cinereous Vulture (Aegypius monachus), Egyptian Vulture (Neophron percnopterus) and Bearded Vulture (Gypaetus barbatus). Until the 2026 reintroduction efforts initiated by Foundation Conservation Carpathia and Rewilding Romania, Romania remained the last EU country whose former vulture guild had not been targeted for active recovery. Despite this exceptional significance in a European conservation context, no comprehensive synthesis of the historical and contemporary distribution of these species in Romania has been undertaken. We conducted a comprehensive review to gather all available vulture occurrence data and present a fully georeferenced database of 1,170 occurrence records spanning 1818-2025. We systematically searched museum collections, historical ornithological literature, modern field surveys and citizen-science platforms. The database documents substantial breeding populations across the Carpathian arc and Dobrogea until the early twentieth century, followed by near-total breeding collapse between the 1920s and 1960s driven by persecution, secondary poisoning and agrarian transformation. In total, 149 confirmed or probable breeding records have been documented for the four species combined, with the most recent confirmed breeding records dating to 1929 (Gyps fulvus), 1929 (Gypaetus barbatus), 1942 (Aegypius monachus) and 1966 (Neophron percnopterus). Non-breeding occurrences increase markedly after 2010, consistent with dispersal from expanding Balkan source populations. The F[a]g[a]ra {square} and Retezat Mountains emerge as the historically most important breeding strongholds for all four species. Our dataset constitutes the most detailed historical baseline currently available for vulture conservation in Romania and is intended to identify key historical sites with high potential for future reintroduction and recovery. Our results show that Romania historically supported the full guild of European obligate scavengers, and that its collapse occurred within barely four decades (1920s-1960s). The dataset highlights the value of reconstructing historical baselines in regions where functional extinction preceded the onset of modern monitoring, and provides an empirical foundation for reassembling a keystone scavenger guild at a continental scale.

West African savannahs provide habitats to diverse species assemblages, yet remain understudied compared to their East and Southern African counterparts. The Niokolo-Koba National Park in southeastern Senegal constitutes one of the largest remaining protected areas in West Africa and supports a mosaic of savannah and forest habitats with a diverse assemblage of medium- and large-sized mammals. Here, we analysed camera-trap data originally collected to monitor predator presence in the northwestern sector of the National Park. We deployed 37 cameras across 37 km{superscript 2} from February 2022 to March 2023, resulting in 13,161 camera-trap-days. We assessed alpha diversity indices and spatiotemporal activity patterns of large and medium-sized mammals across habitat types. Evenness values - the degree to which species abundances are distributed uniformly within a community - were higher in the savannah than in forest habitats, although overall species richness was comparable. In contrast, animal sighting rates were higher in forests than in savannahs. Estimated diel activity mostly corresponded with established species-specific behavioural patterns. Our analyses revealed differential use of certain habitat types across the day, likely driven by spatially segregated sleeping sites and foraging locations. Our results provide a reference for future studies and monitoring efforts and highlight the value of the forest-savannah mosaic for the local species assemblage within the larger ecosystem of Niokolo-Koba National Park.

The IUCN Red List of Threatened Species assigns species to discrete categories based on a common set of criteria to capture relative extinction risk. Some quantitative analyses require a continuous probability of extinction not provided by discrete categories. Furthermore, the criteria may not translate to extinction risk in a universal way across species, because some species attributes are not incorporated into the criteria. Here we calculate extinction risk using Markov Models parameterised with historical IUCN Red List assessment data, and we provide quantitative extinction risk for use in downstream analyses. We find that taxonomy, body size, and habitat specialism interact with extinction risk in ways not fully captured by the existing categories. For example, an Endangered habitat specialist appears equally at risk compared to a Critically Endangered habitat generalist. We hope our findings will support more accurate quantitative biodiversity analyses of species extinctions and declines using Red List data.

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

Preventing extirpations requires timely detection of rapid declines and immediate conservation response. Egyptian fruit bats (Rousettus aegyptiacus) are globally listed as Least Concern, but their genetically isolated population in Cyprus is Critically Endangered. We document a severe ongoing decline of the Cypriot R. aegyptiacus population observed during standardized counts at major roost sites. April 2024 counts at four principal roosts recorded 4633 bats. Surveys in December 2025 documented 554 individuals across the same sites. April 2026 counts revealed a 90.1% decline since April 2024. Additionally, we found numerous dead bats at three roosts, and residents across the island reported dead bats, suggesting an acute mortality event beginning in early 2025. The cause remains unknown. Given the magnitude and pace of decline, this population potentially faces imminent extirpation. We recommend immediate action to protect roosting and foraging habitat, along with coordinated diagnostics, expedited research permits, standardized monitoring, and technical collaboration to identify and mitigate underlying causes of high mortality.

Predation by mammalian carnivores can have cascading, regulatory effects across ecological communities. An understanding of predator diet can therefore provide crucial information regarding their ecology and conservation, as well as their impacts on prey populations. Using scats collected between 2019 and 2023, coupled with estimates of prey abundance from aerial surveys, we characterized lion prey-consumption and preference in Tsavo, Kenya. A lion-specific biomass model applied to prey frequencies in scats revealed that more than 85% of lion diet consisted of large ungulates weighing over 150 kg. While large ungulates were also preferred prey items in terms of their availability, we found a disproportionately high consumption and preference of lions for the endangered hirola and Grevys zebra-- species that were introduced in Tsavo as part of ex-situ conservation programs. Hirola and Grevys zebra populations have historically remained small in Tsavo despite strong recovery efforts, and our results likely indicate a disproportionate impact of lion predation on these small but crucial populations. Preferential predation, coupled with high availability of alternative prey, may trap hirola and Grevys zebra within a predator-pit. Our findings have strong implications for understanding lion diet, optimal foraging, and the potential effects predators have on endangered prey species in a landscape of critical conservation importance.

In an era of severe global biodiversity threats, understanding the link between species traits and their endangerment helps uncover causes of risk and infer threats to understudied species. Most animals have complex life cycles with distinct stages that may face stage-specific threats. Current conservation frameworks rely heavily on adult traits, potentially misjudging extinction risk. Using Chinese anurans as a model, we integrated functional traits from both adult and tadpole stages to examine their association with extinction risk. We found that body size positively correlates with risk in both stages. Microhabitat use related with extinction risk in tadpoles but shows no significant link in adults. Adult relative tympanum diameter and head length also correlate with extinction risk. These results indicate that species vulnerability is shaped by multi-stage traits, with both shared and stage-specific threats. Conservation based solely on adult traits may fail to accurately assess species threats. We call for integrating a whole-life-history perspective into biodiversity assessment and conservation to more effectively address the global biodiversity crisis.

Predation is a major selective force shaping lemur behaviour and population dynamics, yet direct observations remain rare, particularly for small nocturnal species. Here, we document predation on mouse lemurs (Microcebus spp., Cheirogaleidae) in Andohahela National Park, south-eastern Madagascar, and using complementary evidence from radio-telemetry and owl pellet analyses. Two radio-collared individuals were confirmed as prey of endemic snakes, Ithycyphus oursi and Madagascarophis meridionalis (both Pseudoxyrhophiidae), representing the first documented records of Microcebus predation by these species. Examination of owl pellets and prey remains from three sites and from three owl species revealed a single predation event by Asio madagascariensis (Strigidae), likely involving M. tanosi, no evidence of mouse lemur predation by Tyto alba (Tytonidae) despite high local prey availability, and a single and first predation record from Athene superciliaris (Strigidae). Material from A. superciliaris roosts was otherwise dominated by invertebrates, indicating that primate predation is likely opportunistic. Together, these findings expand the known predator guild of mouse lemurs and suggest that snake predation is rarely detected, and its contribution to mouse lemur mortality and population dynamics is likely underestimated. Our findings demonstrate how combining behavioural field observations with dietary evidence can uncover otherwise undetected predation events and clarify predator prey relationships in nocturnal primates.

The Asiatic cheetah (Acinonyx jubatus venaticus), once widespread across West, South, and Central Asia, now survives only in Iran, where its population has declined to the brink of extinction. The current study synthesized 12 years (2012-2024) of monitoring data, including systematic, extensive camera trap surveys across 27 distinct sampling sessions in eight reserves (69,089 trap nights) supplemented by published records of cheetah occurrences on social media to assess the demographic and spatial patterns of this critically endangered subspecies. Our analysis indicates that a total of 24 adult Asiatic cheetahs were identified across the Northern and Southern Landscapes. However, no evidence of reproduction or new individual presence was obtained in the Southern Landscape for over a decade. Meanwhile, the Northern Landscape hosts the remaining population, likely fewer than 30 individuals. Between 2020 and 2024, at least 31 cubs were born in the northern population from six females. However, limited evidence of successful recruitment suggests minimal contribution to population recovery, as only 47.3% of monitored cubs survived beyond their first year. Asiatic cheetahs exhibit extensive mobility across the arid Northern Landscape, frequently traversing unprotected communal lands and a major highway, which increases their vulnerability. While camera trap data have proven effective for individual identification, they are limited in tracking fine-scale movement, emphasizing the urgent need for satellite telemetry. Interventions such as roadside fencing and wildlife underpasses along highways are essential to reduce mortality. These efforts should be complemented by broader conservation measures, including habitat protection and restoration, community-based management of unprotected lands, and enhanced anti-trafficking enforcement. Genetic concerns, especially low effective population size and inbreeding, pose additional threats to viability.

O_LIReintroduction programs are critical for restoring endangered species. However, scientific assessments and management recommendations based on comprehensive vital rates across the entire life cycle remain limited for such programs. The Crested ibis (Nipponia nippon), once nearly extinct, has been the focus of intensive conservation efforts, including reintroduction into its historical range. Here, we systematically evaluate the success of a Crested ibis reintroduction population by integrating long-term field monitoring with population dynamic modeling. C_LIO_LIWe conducted a systematic, multi-year (2023-2025) demographic study of a reintroduced Crested ibis population in Dongzhai National Nature Reserve, China. From 2013 to 2023, a total of 133 captive Crested ibises were released in seven batches within the nature reserve. By 2025, the wild population had exceeded 500. Based on the combination of field monitoring (n = 176 pairs) and GPS telemetry (n = 74 GPS tags, the longest monitoring time lasting 4 years), we quantified reproductive output and mortality rates across six life stages: nest building, incubation, offspring provisioning, fledgling (< 1 year), sub-adult (1-2 years), and adult (> 2 years). C_LIO_LIThe results show that the average clutch size of this population is 3.24 {+/-} 0.08, and each pair of parent birds can rear 1.31 {+/-} 0.12 nestlings to fledging each year. We found that high mortality during the incubation (32.5%, n = 425 eggs), offspring provisioning (34.1%, n = 287 chicks), and fledgling stages (38.6%, n = 63 birds). Key causes included unfertilized eggs, predation, starvation, and human disturbance. On the other hand, the mortalities in the nest building (9.1%, n = 176 pairs), sub-adult (9.8%, n = 28 birds) and adult stage (21.3%, n = 15 birds) were relatively low. Stage-structured matrix model shows a positive population growth of this reintroduced population (growth rate {lambda} = 1.053), with the population expected to increase 13-fold over 50 years (6,858 individuals). Sensitivity analysis indicates that adult survival had the strongest influence on population growth. Correspondingly, we predict that by 2075, its distribution range will expand 13-fold in tandem with population growth, exceeding 51,000 km{superscript 2} and covering several surrounding cities. C_LIO_LIOur comprehensive monitoring, evaluation, and simulation across the full life-cycle confirm that the reintroduced population is successfully established and self-sustaining. This finding addresses a critical research gap: the lack of a scientific and systematic framework for assessing population reintroductions in endangered species. Furthermore, we identified key conservation practices to enhance population growth and stability, including predator control, supplemental feeding, the rescue of weak chicks, and reducing human disturbance through public engagement. To ensure long-term viability, we also recommend implementing genetic management to avoid inbreeding. The resulting framework provides a practical model for improving reintroduction success and promoting species recovery in other endangered species. C_LI

Even during ongoing global biodiversity losses and extinctions, numerous species have shown recoveries in terms of increased abundance and/or range extent. Understanding the mechanisms that contribute to, or limit, these recoveries is critical not just to ensure they continue, but to promote similar recoveries across broader ecosystems. Here, we explore the changes in abundance and range extent of selected 47 recovering species (24 mammals and 23 birds) in Europe using official data reported by EU Member States and supplemented using the Living Planet Index database. We investigate how the diversity of ongoing threats and conservation measures contribute to the likelihood and extent of recoveries. For birds, long-term recoveries were less likely among species impacted by a greater diversity of threats, although this may be mitigated by the diversity of conservation measures in place. Similarly, for mammals, populations with reported threats recovered less quickly while those with management actions in place recovered more quickly. To achieve the aims of the UN Decade on Restoration, we need to ensure, even for recovering species, that threats continue to be reduced and that conservation management actions are ongoing and effective.