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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.
In this paper, I investigate four sites connected to animist narratives in Northern Norway. The unrest associated with these sites is seen as being caused by human activity but carried out by disruptive forces. Sometimes the causes are known; sometimes they are unknown, but still connected to active agencies in these landscapes. The narratives relate to two types of forces that can make a place uneasy: chthonic forces and harmful deeds of humans against nature or other people. Implicit within these narrations and interpretations is an animistic worldview: places can and do remember. The places presented here are situated close to current or past Sámi settlements, suggesting that they are the result of animist and possibly shamanic practices and cosmologies. This reveals an ongoing concern with disruption of human/nature relations and attributed continued meaning through the Sámi narrative tradition. Sámi language originally had no word for nature. Luondo, the name used today, originally meant personality of humans, animals, or places, and illustrates my entry point into these phenomena.
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.
Amphipod samples were collected from the rocky habitat of Arjyapalli beach in southern Odisha, India. The specimens were analysed for morphological characters. One interesting species was observed during the study and was identified as Stenothoe lowryi. The species was previously reported only from Malaysia. The present study confirms the distributional range extension of this species to Indian waters and details a few additional morphological characters.
This study investigates the use of machine learning based image classification techniques to detect debris blocking of urban waterways. Using a dataset comprising 1089 labelled CCTV images of a trash screen located in Cardiff, UK and a comprehensive re-sampling approach, we investigate not only the ability of selected machine learning algorithms to correctly identify images, but also to evaluate the uncertainty of these algorithms conditional on the datasets presented to them. For each candidate model, we considered two datasets: an imbalanced dataset and an under-sampled dataset. The results demonstrate that the performance of a simple logistic regression model was broadly comparable to that of more advanced machine learning models such as vision transformers. The best performing models (vision transformers and logistic regression) achieved an accuracy of more than 80%, while the NetRes50 model achieved an accuracy in the low 70%. This is an important result that opens the possibility for implementing these techniques as part of an operational real-time flood warning system utilising already existing cameras.
Ensuring easy access to clean and safe drinking water using low-cost technology is essential to mitigate the rising water scarcity in emerging economies. Commercial large-scale desalination technologies need significant investment, making them unsuitable for off-grid and small-scale applications. However, this operation can be carried out using a low-cost desalination technology based on renewable energy, known as the solar still. In this research work, a modified basin solar still (basin solar still + internal mirrors + 8 kg gravel + black ink (400 ppm per litre)) was developed and experimentally tested in Visakhapatnam (17.68°N, 83.22°E), India, to determine its appropriateness for sustainable seawater desalination. It produced 14% to 23% more desalinated water than a conventional basin solar still. In addition, its thermal efficiency was between 41% and 42%, which was significantly greater than other basin solar stills reported in literature. In addition, high-quality desalinated water was generated at a cost that was around three times less than the drinking water offered at Indian Railways kiosks. Moreover, the ability to mitigate significant CO2 emissions while also addressing water scarcity demonstrated that the modified basin solar still continues to contribute effectively to the United Nations Sustainable Development Goal 6 (Clean Water and Sanitation).
The circumpolar Arctic region has undergone a major geopolitical transformation because of two external forces altering regional security: climate change and increasing great power competition, notably due to the Russian war against Ukraine. Underscored by the de facto suspension of pan-Arctic cooperation after Russia’s expanded invasion in February 2022, the circumpolar Arctic has fragmented into two distinct blocs: the Russian Federation and the Arctic 7 (A7) group of allied democracies. These blocs are informed not just by different security policies between Russia and its polar neighbours but by differing Arctic security public opinion among their populations. Drawing on an original dataset of 164 polls and surveys from all eight Arctic states taken between 2007 and 2024, we outline sub-regional patterns in security public opinion that demonstrate different attitudes between Russia and the A7 with respect to the two defining issues in Arctic regional security: climate change and great power competition between Russia, China, and USA. We find that climate change is universally considered the most serious security issue in the Arctic; Russia is widely seen as a threat to other Arctic states; China is not seen as a major threat nor as particularly relevant to Arctic security; and USA is strongly supported in all Arctic states but Russia. We also conclude that sub-regional analysis may offer clearer insights into Arctic security public opinion than pan-Arctic analyses.
Effective flood hazard communication is essential for improving public preparedness and response. However, traditional metrics, such as return periods (e.g., 100-year flood) or percentage probabilities, often lead to misinterpretation and reduced public engagement. This study introduces the Nines of Safety (NoS), a novel logarithmic-scale metric designed to improve the clarity and accessibility of flood risk communication. Inspired by reliability engineering and rooted in probabilistic theory, the NoS framework quantifies the probability of avoiding a flood event using the number of consecutive 9 s in its success rate (e.g., 90% = 1 NoS, 99% = 2 NoS), offering an intuitive and scalable measure for both technical and public audiences. This study operationalizes the NoS framework by integrating key geophysical indicators- – elevation, slope, land use and drainage density – and examines how these variables influence flood susceptibility over time. Additionally, it incorporates socioeconomic variables to reflect layered vulnerability, demonstrating that prolonged exposure amplifies risk and gradually erodes safety. A case-based application in Iowa City, Iowa, compares derived NoS scores with the Social Vulnerability Index and reveals a moderate inverse correlation (Pearson’s r = −0.52), supporting the framework’s validity for social risk assessment. The NoS framework offers potential to bridge the gap between technical assessment and community-level flood communication by providing a standardized, intuitive representation of safety probabilities. However, its validation remains limited to a single urban case study; future research should test its performance across diverse geographic and socioeconomic contexts.
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.
Sustainable Development Goal 6.1 seeks universal access to safe drinking water for all by 2030, yet persistent disparities remain even in high-income countries. Indigenous, remote and small communities are disproportionately affected by poor drinking water quality, but comparable evidence to evaluate performance across communities is very limited due to inconsistent monitoring and reporting. To this end, we constructed a community-level meta-panel dataset of 839 communities (4,137 observations) across 4 Australian jurisdictions (Northern Territory, South Australia, Victoria and Western Australia) and Ontario, Canada, over the period 2018–2022. Drinking water quality was assessed using the Australian Drinking Water Guidelines and Canadian Boil Water Advisories. Logistic regression was employed to estimate the probability of accessing good-quality drinking water, with Indigenous status, remoteness, population size and socio-economic condition as key explanatory variables. Results reveal systematic disparities: Indigenous and very remote communities are statistically significantly less likely to have good-quality drinking water than non-Indigenous and regional communities after controlling for other factors. Our findings indicate that structural inequities – rather than geographic or demographic variation alone – are critical determinants of poor drinking water outcomes in small, Indigenous communities in both Australia and Canada.
Scientific data on the influences of salinity shifts on the survival and behavioural attributes of marine animals is valuable to select potential coastal aquaculture candidates/commercial cultivation sites and to devise conservation strategies in the climate change scenario. This study establishes the survival ranges following gradual and abrupt salinity shifts for a high-value marine lobster species, Panulirus homarus. Lethal concentration limits differed between gradual and abrupt salinity shifts, with a broader tolerance observed under gradual shifts. There was 100% survival between 17 and 44‰ and between 26 and 41‰ following gradual and abrupt salinity shifts. As behavioural responses are critical in understanding the physiology and welfare status of animals, behavioural attributes, viz. antennule flicking per minute (AFM) and feed response time (FRT) were evaluated upon salinity shifts from the control (35‰). The sudden increase in AFM was the first visible reaction to the salinity shifts followed by a sustained decline beyond particular ranges in both gradual and abrupt shifts. FRT was significantly decreased beyond specific salinity ranges on gradual and abrupt salinity shifts and the animals became completely anorectic beyond 44–14‰, and beyond 44–23‰, respectively, on gradual and abrupt shifts. A better coping mechanism and a wider range of salinity tolerance were observed for gradual shifts than abrupt shifts.
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.
Populations of Paracentrotus lividus have been widely studied across their geographic range due to their key role as herbivores capable of transforming benthic communities. However, no comprehensive population assessment had previously been conducted in the Canary Islands. We carried out an extensive survey between 2006 and 2009 across five islands and the northern islets of Lanzarote, sampling both intertidal and subtidal habitats. Sea urchin abundance, algal composition, and physical variables were recorded to identify spatial patterns in population distribution. Macroalgal assemblages were grouped into functional categories: turf, Lobophora, brown erect algae, red bushy algae, and crustose corallines. Lobophora showed a strong negative relationship with P. lividus abundance, whereas brown erect algae were associated with the highest sea urchin densities. Island identity emerged as a major structuring factor, particularly in the subtidal, revealing a clear archipelagic gradient: populations were nearly absent in the westernmost island (El Hierro) and progressively more abundant toward the eastern islands. Wave exposure also significantly influenced abundance and size structure, although effects differed between habitats. In subtidal zones, P. lividus was more abundant in exposed areas, whereas intertidal densities peaked at intermediate exposure levels. At smaller spatial scales, substrates characterized by higher structural complexity and porosity supported greater sea urchin abundance. By integrating environmental drivers across spatial scales, this study highlights the combined influence of habitat structure, algal composition, and hydrodynamic conditions in shaping P. lividus distribution, providing a baseline for future management and conservation strategies in oceanic island systems.
Sea cucumber fisheries have continued to expand during the past decade at a fast rate, despite the predictable drop during the COVID-19 period. The exploitations are now qualified as ‘serial’ and ‘contagious’. The most recent trends are shown through the analysis of Food and Agriculture Organization’s capture data, collected from different countries and territories. The mean captures per year, in fresh weight, are over 90.103 tonnes. The mean trade data for years 2019–2021 are given by category of commodities, which complicates the trade analysis. The imports, in quantity and value, show the usual importance of China and Hong Kong, and now of Saudi Arabia. The exports show the importance of the frozen products from Canada. The statistics from Hong Kong in quantities and values (for imports and re-exports) are analysed for the past decade. Globally, catches have increased in comparison to previous studies, with new countries and territories developing export fisheries, new species targeted from new regions, and new products traded. The continued growth and expansion of the global sea cucumber trade is alarming as the sustainability of many species-specific fisheries remains of great concern. Stronger conservation measures, and their implementation, at national, regional, and international levels, are required to effectively protect biodiversity, promote sustainable resource use, and address the escalating impacts of the increasing exploitation efforts.
Long-distance migratory birds rely on pre-migratory fuelling to complete extensive flights. Global change and invasive species may threaten food resources critical for this process. The Bristle-thighed Curlew Numenius tahitiensis breeds in Alaska and winters across Pacific islands. Its population in French Polynesia has halved in the past two decades, raising conservation concerns. Introduced Pacific rats Rattus exulans are suspected to deplete terrestrial food resources on atolls, potentially impacting curlew fuelling. This study characterises the diet of Bristle-thighed Curlews during April, their pre-migratory fuelling period, using DNA metabarcoding of 61 faeces collected across rat-infested and rat-free islands in the Tuamotu Archipelago – of which 38 provided dietary data. Several molecular operational taxonomic units (MOTUs) were identified, covering arthropods, annelids, nemerteans, molluscs, reptiles, and plants. The curlew’s diet was dominated by crabs (45.8% MOTUs, 66.1% reads), particularly Pachygrapsus fakaravensis and Grapsus albolineatus, followed by insects (35.8% MOTUs, 11.5% reads), notably Pycnoscelus cockroaches. Plant material, mainly from coconut trees, represented 17.4% of reads. The diet was significantly more diverse on rat-infested islands, with higher MOTU richness and a predominance of crabs (73.7% reads). In contrast, rat-free islands showed a more balanced intake among crabs, insects, and plants. Rat presence shifts dietary diversity and composition, possibly by altering prey availability. Despite greater diversity on rat-infested islands, optimal fuelling appears to be associated with abundant crabs and insects on rat-free islands. Findings highlight the importance of managing invasive rats to maintain key food resources for this Endangered migratory bird. Further research on prey availability and nutritional quality across islands is recommended to inform conservation strategies.
This study reports the first record of Caprella moradi Momtazi, Sari & Darvish, 2020 from India. The specimens for this study were collected from Diu and Veraval coast of Gujarat State, India. Caprella moradi can be identified by the presence of four rows of small setae on body surface, curved anterior margin of male gnathopod 2 propodus and unequal size of gills 3 and 4. Caprella moradi can be differentiated from its close congener Caprella danilevskii; Czerniavski, 1868 by these consistent morphological characters. Examination of materials collected from Gujarat and their comparison with published figures indicates that the previous report of C. danilevskii from India actually corresponds to C. moradi.