Green Peafowl Pavo muticus, a dry forest specialist, has experienced declines across its range in mainland South-East Asia due to habitat degradation, habitat loss, and hunting. In Thailand, the species’ remaining habitats have been grouped into four strongholds where long-term viable populations are thought to persist. For two of these strongholds, extensive population estimates are available, but for the other two (north-western and eastern Thailand), only a single site-based estimate currently exists. To address the gap, additional density estimates were derived from distance sampling in OpLuang National Park (north-western stronghold) and the Phnom Dangrek Range (north-eastern stronghold). Remaining suitable habitats were identified using a Generalised Linear Model (GLM) and the threats these populations face were assessed. In the north-western stronghold, density was estimated at 0.51 calling birds/km2 in OpLuang National Park, with suitable habitat covering 7,197 km2 (2,657 km2 within protected areas) and deforestation totalling 1,374 km2 (963 km2 consecutive hotspots, 377 km2 sporadic hotspots, and 34 km2 new hotspots). In the north-eastern stronghold, density was estimated at 0.93 calling birds/km2 in three of six protected areas across the Phnom Dangrek Range, with suitable habitat covering 9,917 km2 (3,518 km2 within protected areas) and deforestation totalling 3,407 km2 (1,954 km2 consecutive hotspots, 1,142 km2 sporadic hotspots, 309 km2 new hotspots, and 2 km2 persistent hotspots). Our results confirm the importance of both strongholds for the long-term survival of the species. However, they also highlight the need for improved management to systematically monitor larger portions of suitable habitat, enhance population growth, and mitigate threats from deforestation, fire, and hunting by feral dogs.

Effective conservation of declining migratory species requires identifying habitats used during each stage of the annual cycle and the links between them. The Little Blue Heron Egretta caerulea, a long-legged, colonial-nesting, wading bird species that primarily forages in shallow-water wetlands, is declining throughout much of its range. A lack of understanding of its annual cycle movements prevents identifying when and where populations face limiting pressures, hindering conservation efforts. This study quantifies Little Blue Heron annual cycle movements, including space use at wintering and breeding sites, colony locations, migration distances, phenology, and site fidelity of herons from two important wintering sites on Florida’s Gulf Coast that differ in availability of fresh water. Little Blue Herons tagged with GPS transmitters (n = 30) showed a partial migration strategy; however, the ratio of migrants to residents was substantially different between the two study sites. Additionally, these birds established breeding colonies in both inland (n = 10) and coastal (n = 12) wetlands throughout the south-east USA and western Cuba (n = 2) and travelled a mean of 4.46 (SE = 0.87) km from their colony to forage. About 95% of individuals established colonies within freshwater wetland habitats, regardless of their wintering site, providing support that availability of fresh water during the breeding period is a key element of the habitat for this species. The results of this study suggest that management decisions aimed at minimising the threats to high-value wintering sites will benefit this species. The coastal systems examined supported wintering individuals for at least half of the full annual cycle. During this period, individuals maintained small home ranges (mean = 153.71, SE = 17.4 ha), did not make any significant within-season movements to other locations, and displayed strong inter-year site fidelity (0.49–0.85 BAI overlap), suggesting that these are areas that provide high quality habitats, justifying continued protection.

Survival is a key life history trait influenced by climate variability and resource availability in many bird species. Understanding the factors affecting survival in threatened species is critical for effective conservation management. However, we lack knowledge regarding survival rates and their annual variations for most threatened species. In this study, we use mark-recapture data collected in eastern Spain between 2011 and 2019 to estimate the annual adult survival of the Endangered Dupont’s Lark Chersophilus duponti, a steppe specialist passerine. We also aim to assess whether survival rates are linked to plant productivity, as a surrogate of resources available, and climate variability during the post-breeding (autumn) and winter periods. A total of 113 adults (89 males and 24 females) were ringed, which yielded 43 recaptures. The average adult survival rate over the nine-year period was slightly higher than previous estimates for Dupont’s Lark and other related species. Nonetheless, we observed substantial annual fluctuations in survival (ranging from 0.34 to 0.80), largely driven by winter climate conditions. Survival rates decreased during winters with a higher number of frost days (below 0ºC) and increased accumulated rainfall. These findings provide new insights into the population dynamics of the species and suggest that factors other than adult annual survival may be contributing to its declining status. Among those factors, a critical area for further research is to study and characterise the dispersal patterns and survival of juvenile birds, which remain largely unknown for this species.

The determinants of nest-site selection and nest success are important for conservation planning for endangered birds. Here we examine factors driving nest-site selection and success for the Mariana Crow Corvus kubaryi, also known as the Åga, across the entire range of the population, by comparing 370 nests that were found during surveys (2014–2021) against random points sampled from all forested areas on the island. Nest-sites were more likely to have high canopy cover than random points, while proximity to human infrastructure (e.g. roads, buildings) did not impact nest-site selection. None of our tested covariates impacted nest success, nor did the land-cover type in which the nests were found. Our results suggest that the Åga is able to nest successfully in close proximity to humans, and that nest success is not negatively affected by current land-use practices. Future research on the low nest success rate (23.9%) would be most fruitfully targeted towards local biotic stressors, such as nest predation or environmental factors, which may exacerbate the unknown inflammatory disease that afflicts many wild nestlings.

National and continental-scale bird monitoring schemes, such as the Pan-European Common Bird Monitoring Scheme (PECBMS), are essential for tracking bird population trends across broad spatial scales. However, while these frameworks provide invaluable data for population monitoring, they may be less accurate in estimating species densities at small spatial scales, particularly for habitat-specialist species like the Red-backed Shrike Lanius collurio. This species is listed in Annex I of the EU Birds Directive, and its effective monitoring is a legal conservation obligation for EU Member States under the Natura 2000 framework. Ensuring accurate data on its population status is therefore critical for meeting international biodiversity targets. To evaluate this limitation, we compared density estimates from the Common Breeding Birds Survey (MPPL) with those obtained from intensive, targeted surveys across 53 study plots, each covering an area of 1 km², in eastern Poland. Although density estimates from MPPL and the targeted field study were correlated, a deeper analysis revealed that MPPL (2.1 individuals/km²) consistently underestimated densities recorded during targeted surveys (3.9 breeding pairs/km²). Using Generalised Linear Models (GLMs), we explored the habitat characteristics that may contribute to these discrepancies. Only two predictors, i.e. the proportion of buffer zones around arable fields and around mixed crops, were significantly associated with underestimation. In both cases, a higher share of buffer zones led to a greater difference between MPPL and targeted estimates, indicating that landscape structure influences detectability. Differences in survey timing between the two approaches, with MPPL visits conducted earlier in the breeding season, coupled with species-specific breeding behaviours (including peak activity later in the breeding season) may have influenced these differences. This study highlights that although bird surveys are an indispensable tool for analysing trends and comparing densities between surfaces over large spatial domains, their usefulness for studies at small spatial scales may be limited.

Understanding the causes and drivers of extinction is critical for mitigating future anthropogenic extinctions. This study explored the extinction process of the Crested Ibis Nipponia nippon in Japan, focusing on the last wild population on Sado Island. An integrated population model–population viability analysis (IPM-PVA) framework was applied to estimate demographic parameters and population dynamics using four historical data sources, i.e. population counts, records of dead or rescued individuals, reproductive data, and captures for captive breeding. The IPM estimated an average of 0.703 fledglings per breeding pair per season, with adult and juvenile survival rates of 0.870 and 0.730, respectively. Human disturbances were found to substantially reduce fecundity. PVA results indicated an extinction probability of 56.6% under observed historical conditions, which could have been reduced to 11.2% if human access to nesting forests had been restricted. The study identified low fecundity caused by human disturbance at nest-sites as a likely contributor to the species’ extinction. Despite the need for cautious interpretation due to data limitations, this study highlights the practical utility of the IPM-PVA framework in providing detailed insights into the extinction process.