Assessment of anthropogenic macro-litter and its impacts on the seagrass meadows of the remote Andaman and Nicobar Islands, northern Indian Ocean.

Despite the rapid growth of environmental DNA (eDNA) biomonitoring, soil-derived eDNA remains underutilized for profiling biodiversity in terrestrial ecosystems. Here, we evaluated the performance of soil eDNA metabarcoding and potential sources of bias in characterizing terrestrial vertebrate and plant biodiversity compared with conventional survey methods. Across five locations sampled in two seasons, soil eDNA detected vertebrate species richness comparable to camera trapping, and achieved greater taxonomic recovery in winter. However, the large fraction of species uniquely detected by each method highlights their complementarity. Soil eDNA and camera trapping further showed significant concordance (Spearman's ρ = 0.70) in the relative abundance of detected species, although the strength of this correlation varied among seasons and with species traits. For plants, soil eDNA uncovered markedly greater taxonomic richness than visual surveys, and this detection capacity was not influenced by season, suggesting broad spatial integration of plant eDNA in soils and residual deposition from previous seasons. A cost-efficiency analysis indicated that soil eDNA requires significantly less financial and time investment per detected taxon compared with conventional methods. Our findings highlight soil eDNA metabarcoding as an effective biodiversity monitoring tool, enabling the simultaneous detection of diverse biological communities from limited soil samples across broad spatial and temporal scales.

Background Environmental DNA (eDNA) has transformed biodiversity monitoring, but its application for long-term ecological assessment remains limited by uncertainty in the temporal stability and consistency of eDNA signals, as well as by specialized workflows that limit accessibility for community-led programs. Expanding participation in biomonitoring requires approaches that are both logistically feasible and scientifically robust. Here, we evaluated eDNA tools for coral reef monitoring in Hawai'i by comparing (1) coral-specific genetic markers for tracking benthic community dynamics through time, and (2) passive eDNA samplers (PEDS) as a low-effort alternative to active filtration. This research was conducted with local stewardship organizations on O'ahu, Hawai'i, positioning eDNA as a complementary tool to place-based ecological knowledge that can inform conservation strategies and enhance ecological monitoring. Results Across five broad taxonomic markers, we detected diverse reef communities spanning 17 phyla, with consistent regional differences in community composition, including clear differentiation in algal assemblages. Passive samplers recovered comparable taxonomic richness to active filtration when sampling effort was standardized, but showed greater variability among replicates, whereas active methods more consistently detected rare and transient taxa. Despite this, passive samplers captured similar broad-scale community patterns with reduced logistical effort. For coral monitoring, all three markers (12S, 16S, ITS2) showed strong correlations with visual cover and detected more genera than visual surveys. Among these, 16S showed the strongest and most consistent performance across temporal replicates, while ITS2 showed greater temporal variability. Conclusions Accessible eDNA approaches can generate ecologically meaningful data for reef monitoring when matched to specific objectives. Passive samplers provide a scalable, low-barrier option for widespread community biomonitoring, while active filtration remains important for detecting rare taxa. A multimarker approach enabled detection of native, endemic, and nuisance taxa, offering an ecosystem-level perspective for management. Given the relatively slow pace of change in coral assemblages, periodic eDNA surveys may provide a useful and practical longer-term complement to rapid visual assessments of coral cover. Integrating these tools with local stewardship efforts can expand participation in eDNA biomonitoring while supporting conservation in urbanized, culturally significant reef systems.

Road infrastructure deterioration is a critical challenge for regional road authorities in Indonesia. This study applies the Surface Distress Index (SDI) method through a systematic visual survey to assess the structural pavement condition of a 4,500-meter section of Deandels Road in Probolinggo Regency, East Java, covering 45 segments of 100 meters each. SDI scores were computed by evaluating crack area, crack width, pothole count, and rutting depth per segment. Results show that 66.7% of segments are in Good condition (SDI < 50), 8.9% Fair, 22.2% Light Damage, and 2.2% Severe Damage. The most critical failure was identified at STA 2+900–3+000 (SDI = 155), requiring full reconstruction. A maintenance priority framework yields a total estimated cost of IDR 937,284,642.47. The SDI method proved effective as a practical, low-cost tool for pavement management in resource-constrained regional road authorities

Contrasting pollution sensitivity for temperate reef assemblages revealed by microhabitat-resolved eDNA, algal sampling and visual surveys.

Life in colour: The influence of habitat colouration on the recruitment of coral reef fish.

Monitoring deep-sea biodiversity is challenging because conventional methods, such as net-sampling and visual surveys, require substantial logistical effort. Environmental DNA (eDNA) offers an alternative for detecting marine organisms; however, its application in deep-sea ecosystems is limited by the sampling accessibility. Because the influence of long‑pipeline transportation on eDNA is unknown, we compared two deep-sea water sampling methods: pumped deep-sea water (pumped method) and water collected near the intake using a Niskin bottle (Niskin method). Samples were collected from pumping stations in Sagami and Suruga bays, Japan, and baited camera observations were conducted to verify eDNA-based detections. In Sagami Bay, both sampling methods detected similar numbers of fish species. In Suruga Bay, the Niskin method exhibited higher species diversity and steeper accumulation curves than the pumped method. The habitat depth ranges of identified species corresponded to the water intake depths in both bays, supporting the effectiveness of the pumped method. Fish community composition showed substantial overlap between methods, and baited cameras recorded 11 and 17 fish taxa in Sagami and Suruga bays, respectively, with 7 and 10 taxa matching eDNA detections. These findings indicate that eDNA metabarcoding of pumped deep-sea water is a feasible method for monitoring deep-sea fish biodiversity.

This study aimed to evaluate and compare the efficiency, safety and accuracy of robot-assisted internal fixation and traditional freehand percutaneous screw in talar neck fracture treatment. This study included 23 patients in the robot-assisted group and 23 patients in the traditional group. Age, injured side, average post-operative follow-up time, time from injury to surgery, operation time, intraoperative blood loss, intraoperative fluoroscopic dose, fracture healing time, American Foot and Ankle Surgery Association (AOFAS) ankle-hindfoot score, Visual Analogue Scale (VAS) score and 12-item Short-Form Survey (SF-12) score were recorded and compared. This study revealed no statistical difference in baseline characteristics between the two groups, as well as the average post-operative follow-up time, injury to operation time, intraoperative blood loss, fracture healing time, VAS score, 12-item Short-Form Survey (SF-12) score and AOFAS score (P > 0.05). A significant difference was found between the robot-assisted group and the traditional group at the time of operation and intraoperative fluoroscopic dose (P < 0.05). Robot-assisted screw placement for talar neck fractures achieved clinical outcomes comparable to those of traditional surgery, with the advantages of significantly shorter operation time and lower intraoperative fluoroscopic dose. Robot-assisted surgery appears to be a safe, effective, and low-radiation alternative for selected talar neck fractures (Hawkins type II).

Although cigarette butts (CBs) are known as a hazardous waste and an important litter in public environments, the density of littered cigarette butts in rural areas and the concentration of pollutants leaking from them remain a knowledge gap. This study aimed to investigate the difference in cigarette butt density in urban and rural areas of Iran and the environmental consequences caused by the leakage of various pollutants from them, by comparing the Cigarette Butt Pollution Index (CBPI). Visual surveys were conducted in seven locations in urban environments and sixteen locations in eight villages. The range of cigarette butt density in urban environments was 0.25/m2 to 0.81/m2 (0.46/m2 on average), while in rural environments, it was 0.8/m2 to 2.33/m2 (1.54/m2 on average). Additionally, the CBPI in rural areas was three times higher than in urban areas, resulting in an average CBPI of 31.24 in rural areas and 10.7 in urban areas. In addition, the higher durability of cigarette butts in rural environments resulted in the leakage of 1.09-2.38 µg/m2 of heavy metals, while the leakage of metals from littered cigarette butts in urban environments was estimated to be 0.065-0.406 µg/m2. Developing public services such as cleaning systems in rural environments is essential to reduce pollution caused by cigarette butts.

ABSTRACTUnderstanding elevational patterns of biodiversity is essential for conservation planning. However, the spatial distribution pattern of lizards in the central Himalayan elevation gradient has rarely been investigated or is mostly from outdated literature. We carried out a study on the occurrence and associated factors of lizard species across the elevation gradients of Chitwan Annapurna Landscape (CHAL) during 2018–2019. This study was carried out by visual encounter survey along the transects (100 × 5 m) and examined the patterns of lizard species richness. We reported 23 species of lizards across our study where most observed species were Calotes versicolor (n = 405), followed by Hemidactylus flaviviridis (n = 250), and Laudakia tuberculata (n = 128), whereas the least observed species were Phrynocephalus theobaldi, Asymblepharus nepalensis, and Lygosoma albopunctata which were observed only twice. We observed that species richness varied significantly with elevation (Kruskal–Wallis χ2 = 41.29, p = 0.0076), although the monotonic relationship was weak (Spearman's ρ = 0.071, p = 0.031). Beta diversity was mostly driven by species turnover rather than nestedness. We observed significant non‐linear impact of elevation on gamma diversity (edf = 2.92, p < 0.001), where terrain ruggedness positively influenced the lizard species richness (β = 0.383, p < 0.001) and canopy cover had a negative effect (β = −0.154, p = 0.033). Our study demonstrates that the lizard diversity in CHAL is structured by non‐linear elevational dynamics and microhabitat heterogeneity. Also, we found a strong turnover of species across elevation bands. These results emphasize the ecological need to consider ecotonal zones and topographic complexity to conserve and maintain reptilian diversity in the Nepal Himalayas. Further, detailed and long‐term studies are needed to develop conservation initiatives and fill gaps in knowledge of lizards in the human‐dominated fragmented landscape of the Central Himalayas.

In coastal ecosystems, chemically rich species like gorgonians rely on specialized metabolites and symbiotic microbes for health and defense. In the Southwestern Atlantic, the elephant ear coral Phyllogorgia dilatata builds structurally complex forests and provides habitat for several species. Recent declines in cover have been linked to widespread disease, fouling, and necrosis. The loss of chemical defense due to anthropic perturbation has never been reported in the marine environment. We investigated whether pollution-driven stress could lead to a dysfunctional holobiont and impairment of its chemical defense. Using chromatography coupled to high-resolution mass spectrometry and molecular networking, we profiled secondary metabolites and used 16S rRNA gene amplicon sequencing to characterize microbial communities, relating these data to visual surveys of P. dilatata gorgonian forests. Defense compounds were found only in colonies far from pollution sources and correlated with bacteria associated with healthier environments. In contrast, pathogenic and sewage-associated bacteria dominated near the polluted site, where defenseless colonies of P. dilatata showed more disease and impaired health. Our results indicate that microbial pollution affects the capacity to modulate the microbiome through the use of infochemicals and leads to disruption of symbiosis and loss of chemical defense.

Spatio-temporal dynamics of floating marine macro-litter in Italian waters (2018-2023): The impact of the COVID-19 pandemic.

The European adder (Vipera berus), classified as critically endangered in Germany, faces severe threats from habitat loss, particularly the decline of primary habitats such as peatlands. Peatland restoration is essential but may pose risks when hibernacula are not considered during rewetting, potentially leading to flooding, site loss, and population declines. Similar risks arise from construction activities in secondary habitats. Protecting these key sites is therefore vital for species conservation but requires reliable methods to locate them. Traditional monitoring approaches, such as visual surveys and telemetry, are often invasive, imprecise, or resource-intensive. This study tested whether a trained adder detection dog could identify adder scent-using sheds and fecal swabs-beneath substrate in controlled line-up experiments and under field conditions. In the line-up tests, we assessed how sample type, burial depth, and substrate influenced detection performance, whereas field searches evaluated detection success under more realistic conditions. In a pilot study, we further examined whether the dog could generalize from collected odor samples to live adders by testing its ability to locate the hibernacula of two previously tagged individuals. In the line-up experiments, the dog identified both sheds and fecal swabs with high sensitivity, performing slightly better with sheds. Detection remained effective at depths of up to 1.2m, although detection success declined with increasing depth. Under field conditions, the dog reliably detected samples buried at a depth of 50cm without any false indications. In the pilot study, the dog successfully located hibernating adders, demonstrating that training non-invasively with collected odor samples rather than live animals can be sufficient for this purpose. These findings suggest that detection dogs represent a promising, non-invasive, and efficient tool for locating adder hibernacula. Future studies should include multiple dogs, larger sample sizes, and additional tagged individuals to further validate detection performance under field conditions.

The Gulf of Squillace, in the Calabrian Ionian Sea, where we have been conducting scientific research and marine monitoring since 2019, has proven to be an important area for pelagic animals, including seabirds and sea turtles. Among these, the presence of cetaceans such as bottlenose dolphins, Risso's dolphins, and striped dolphins is regular, while other species are less frequent visitors. Over the years of monitoring, it has become clear that multiple factors contribute to the degradation of the coastal marine environment, particularly the presence of marine debris. Floating dangerous debris for cetaceans (DDFC) emerge as one of the main anthropogenic threats to the conservation of marine ecosystems and pelagic megafauna. During autumn and winter, marine litter predominantly originates from extreme weather events and riverine inputs. In contrast, during spring and summer, most debris is generated by maritime activities such as fishing, recreational boating, and coastal tourism. A monitoring survey conducted in 2024 and 2025, covering about 1,400 km, analyzed the distribution of floating macro-debris and cetaceans. Data collection was performed via visual surveys from inflatable boats, recording debris type and the presence of marine species. Results indicate a predominance of synthetic polymers, followed by fishing gear, wood, and metals. This study quantifies the potential risk of interaction by analyzing the spatial overlap between cetaceans' sightings tracks and floating dangerous debris for cetaceans. The primary objective is to identify high-risk areas to support evidence-based conservation strategies and mitigate programs, such as source prevention and debris removal. The presence of multiple cetacean species underscores the ecological importance of this region, which includes the SAC “Fondali di Stalettì” and the Marine Park “Baia di Soverato,” further justifying the need for targeted management recommendations.

ABSTRACT Crustose coralline algae (CCA) are key reef‐building organisms, yet their fine structures make traditional visual surveys time‐consuming and limit large‐scale monitoring. This study evaluates the potential of unmanned aerial vehicles (UAVs) for monitoring CCA coverage on intertidal reefs along the Taoyuan coast, Taiwan. Three experiments conducted between 2022 and 2024 were designed to assess the effects of flight altitude, sensor type, classification approach, and the feasibility of large‐scale surveys. A supervised Random Forest classifier was applied using five color indices (R–G, G–B, ExG, ExGR, and NGRDI) to evaluate their effectiveness and identify the optimal combination for CCA classification. Results indicate that classification accuracy was primarily governed by image resolution. Multispectral imagery, under typical UAV configurations, was insufficient to resolve millimeter‐scale CCA features, whereas low‐altitude visible‐light imagery (&lt; 2 m above ground level) provided sufficient detail for reliable identification. Although per‐pixel classification accuracy remained moderate (Kappa &gt; 0.4), the derived CCA coverage estimates showed strong agreement with reference observations ( r &gt; 0.87), indicating that low‐altitude visible‐light UAV imagery provides a robust basis for large‐scale ecological assessments. Overall, UAV‐based surveys combined with automated classification provide an efficient and scalable framework for mapping and monitoring CCA and reef habitats, with potential extension to other taxa.

Opportunistic visual surveys of the Ross Sea and the Amundsen Sea were conducted (25 January– 18 February 2026), amounting to 1,015 nautical miles of search effort (83 hours), of which 763 nautical miles (62.4 hours) were south of 60°. Of 192 cetacean sightings, 153 were identified to species level: 69 humpback (n = 179), 34 fin (n = 90), 27 Antarctic minke (n = 71), 11 Antarctic blue (n = 21), seven killer (n = 40), one Arnoux’s beaked (n = 25), and one sperm (n = 1) whale(s). Of the unidentified sightings, 36 were baleen whales and three were beaked whales. Blue whales with calves were recorded in coastal waters off Cape Adare.

Changes in marine animal communities shape ecological processes and ecosystem functioning. Monitoring temporal community dynamics is increasingly important under global change, yet remains challenging because community fluctuations can arise from multiple natural processes and are difficult to assess. Passive acoustic monitoring of signals produced by marine fauna offers a non-invasive means of tracking community dynamics, providing continuous, high-resolution data that capture temporal patterns often missed by traditional methods. Despite their potential as proxies for macrofaunal assemblages and associated dynamics, the responses of acoustic communities to environmental variability in marine ecosystems remain largely unexplored. This study aimed to characterize fish acoustic communities in a tidal European kelp forest and identify the environmental drivers shaping their temporal variability. Continuous acoustic recordings were combined with environmental measurements and underwater visual surveys to address these objectives. Generalized linear models revealed that diel and tidal cycles were the dominant drivers of acoustic activity, diversity, and community composition during the summer study period. Other environmental variables had weaker effects, reflecting the fauna’s adaptation to marked short-term fluctuations in this dynamic ecosystem. Acoustic activity and richness increased at low water height, contrasting with higher visually observed fish abundance at high water height. This discrepancy suggests that sound production reflects behavioural interactions rather than fish abundance alone. The greater number of sound types (26) relative to observed species (19) indicates either behavioural sound diversity within species or the presence of undocumented soniferous taxa. Calmer sea conditions also promoted higher vocal activity and acoustic richness. This study provides an unprecedented description of kelp forest acoustic communities in Europe, demonstrating the value of ecoacoustics to complement visual surveys for capturing natural variability and establishing essential baseline information for detecting long-term ecological shifts in these climate-sensitive habitats.Graphical Supplementary InformationThe online version contains supplementary material available at 10.1186/s12862-026-02521-z.

Are visual surveys outdated? A case study comparing visual surveys designed for sun coral assessment and emerging 3D photogrammetric approaches.

Population assessments can be used to determine species' viability and inform conservation efforts; however, obtaining sufficient data quality and quantity can be challenging when monitoring resources are scarce. Brook Floater (Alasmidonta varicosa) is a freshwater mussel that is state listed in the United States as endangered or threatened in 10 of the 14 states it occupies. Despite the conservation concern, little is known about the size and demographics of most Brook Floater populations. The primary objective of this study was to determine demographic parameters (abundance and survival) for Brook Floater at five newly established, long-term monitoring sites in Maine and Massachusetts, United States. A secondary objective was to evaluate tradeoffs of potential future sampling strategies by state natural resource agencies at these monitoring sites. Mussels were sampled at each site using visual and tactile snorkel surveys twice each summer during 2018-2020 and marked with alphanumeric tags to distinguish individuals. We considered a candidate set of capture-recapture models that allowed parameters to vary depending on year, sampling occasion, and individual shell length. Abundance estimates among sites varied widely, from 29 individuals (range: 12-119) in the Nissitissit River in Massachusetts to 311 individuals (range: 307-320) in the East Branch of the Pleasant River in Maine. Annual survival was high across all sites (0.87-0.96). Given the differences in capture probability and abundance between states, we determined the statistical power available to detect given population declines in Massachusetts and explored alternative population abundance estimators in Maine. The power analysis suggested that the existing sampling regimen in Maine is likely adequate while sampling in Massachusetts may require additional occasions each year to realistically detect population declines with sufficient statistical power. This analysis demonstrates the utility of considering sampling frequency when designing capture-recapture studies for freshwater mussels and other taxa.

Monitoring cetacean populations is essential for understanding the status of marine communities. In this regard, environmental DNA (eDNA) metabarcoding is an increasingly popular innovative and non-invasive genetic tool for marine biodiversity monitoring, particularly useful for assessing the populations of highly mobile species with a wide distribution range, such as cetaceans. In this study, we compared cetacean species detection and distribution patterns obtained through eDNA metabarcoding with the sighting records obtained during simultaneous traditional visual monitoring. A total of 258 seawater samples was analysed, collected at 129 sampling stations during the SCANS-IV survey carried out in oceanic waters of the North Atlantic Ocean. Nine cetacean species were identified by eDNA metabarcoding and ten by visual monitoring; three species were detected solely by eDNA, while four were exclusively detected by visual observation, demonstrating the complementarity of the two methods. The four most frequently sighted species were also the most frequently detected species in eDNA samples, showing similar detection frequencies and distribution patterns at broad and intermediate spatial scales. At a finer scale, however, species occurrence did not overlap between methods. Additionally, eDNA provided new insights into striped dolphin (Stenella coeruleoalba), which may be under-represented in traditional monitoring data. Overall, the results support the use of eDNA metabarcoding as a valuable complementary monitoring tool for assessing cetacean diversity and distribution, providing additional information on species presence throughout the study area. This is particularly relevant for species that are rarely recorded visually and for which there is insufficient information to design and implement appropriate management strategies.