Search Results (366)

Environmental contamination by rare earth elements (REEs) is increasing globally due to their extensive use in modern technologies, medicine, agriculture, and aquaculture. Their release into aquatic systems via wastewater discharge, industrial emissions, surface runoff, and atmospheric deposition has raised concerns regarding their environmental fate and potential ecotoxicological effects. Despite this, information on REE accumulation in marine predators remains limited. This study provides a multi-species assessment of REE bioaccumulation in elasmobranchs. Concentrations of 14 REEs (Ce, Dy, Er, Eu, Gd, Ho, La, Lu, Nd, Pr, Sm, Tb, Tm, and Yb) were quantified in liver and muscle tissues of six elasmobranch species collected from demersal and deep-sea habitats along the Portuguese continental shelf. Generalized linear models (GLMs) were used to evaluate differences in REE concentrations among species and tissues, and to explore potential patterns associated with ecological traits. Results indicated that REE concentrations varied significantly across tissues and species, with muscle generally exhibiting higher accumulation than liver. Overall, this study provides the first comprehensive baseline of REE bioaccumulation in elasmobranchs from the Portuguese coast, contributing to a better understanding of emerging contaminants in marine food webs. These findings have important implications for environmental biomonitoring and highlight potential risks associated with seafood consumption. Full article

Introduction: Freshwater ecosystems are global biodiversity hotspots, yet they remain highly vulnerable to biological invasions. Non-native freshwater fish species (NNFS) have established self-sustaining populations across nearly all biogeographic realms, reshaping regional ichthyofaunas and driving community-level impacts through predation, competition, hybridisation and ecosystem disruption. Critically, both foreign introductions and within-country translocations (extralimital species) contribute to this process, yet the latter remain more weakly regulated and consistently under-studied in invasion risk frameworks. Objective: We developed a stage-structured profiling framework to jointly evaluate foreign and extralimital NNFS in Greece and predict three sequential invasion outcomes, establishment, spread and integration, with the goal of identifying the ecological traits and pathway variables that best explain invasion success at each stage and informing management policy. Methodology: We compiled a dataset of 63 NNFS recorded in Greek freshwaters (36 foreign, 27 extralimital), characterised by eleven ecological, biogeographic and anthropogenic attributes. Logistic and multiple regression models and classification and regression trees (CART) were fitted independently for each invasion stage, with cross-validated predictor screening to limit multicollinearity and a taxonomy-based covariate to account for phylogenetic non-independence. Results: All 27 extralimital translocations established successfully, compared with only 11 of 36 foreign introductions, underscoring the disproportionate establishment success of within-country movements. Establishment probability was positively associated with high physiological tolerance and proximity to the nearest native source, and negatively associated with maximum adult size; propagule pressure provided only weak additional support. Spread across drainage basins was driven primarily by introduction effort and physiological tolerance. Integration increased with introduction effort, while the CART identified distance from the nearest native source as the primary partition of widespread, high-abundance outcomes, with trophic level further structuring outcomes among extralimital taxa. Conclusions: Our results indicate that management frameworks focused solely on foreign NNFS substantially underestimate invasion risk from within-country translocations. A compact set of predictors, biogeographic proximity, physiological tolerance and introduction effort, offers a practical, pathway-inclusive screening tool to guide prevention, surveillance and early detection in Mediterranean river networks, addressing a recognised European policy gap where extralimital movements remain more weakly regulated than foreign introductions. Full article

Quantifying the impact of land use changes on the threat of flash-floods is a critical consideration in flood hazard planning and risk reduction, and is an area of active research. Here, a coupled Weather Research and Forecasting model hydrological extension package (i.e., WRF-Hydro) modeling approach is applied to simulate flash-flooding processes for short-duration, localized, intense precipitation events. To better understand the effect of urbanization on flash floods, a series of numerical experiments is performed surrounding Ellicott City, Maryland, a location which has experienced both significant heavy rainfall events and suburban development over the past several decades. Two intense rainfall events occurring on 30 July 2016 and 27 May 2018 are investigated, respectively, to first calibrate the hydrologic model performance and then quantify the sensitivity of flash flooding to varying degrees of urbanization. Performing the same experiments using observed historical land use states is of more limited insight, as the thrust of suburban development in the Ellicott City region significantly predates satellite-derived land use datasets. Results confirm that urbanization produces larger river streamflow, higher water stages, faster hydrologic responses to achieve peak flow discharge, and shorter recession limbs, even for very intense, short-duration events. The collective findings suggest that WRF-Hydro is applicable for both watershed flash flood prediction and hypothesis testing, and demonstrates potential utility to urban development decision-makers in locations such as Ellicott City, which could face future increases in catastrophic flooding. Full article

Arthropod natural enemies—encompassing predators and parasitoids—form the backbone of sustainable agriculture, delivering irreplaceable ecosystem services via biological pest suppression. Driven by global demand for eco-friendly alternatives to synthetic pesticides, research in this domain has grown sharply over the past decade. Here, we report a systematic bibliometric analysis of 6515 Web of Science Core Collection papers focused on arthropod natural enemies in biological control (2016–2025), with the goal of charting the field’s intellectual structure. Performance metrics confirmed an initial rapid increase from 2016 to 2019 followed by a plateau and a slight rise in 2025, with the US, China, and Brazil dominating output. Keyword co-occurrence networks pinpointed core themes, including conservation biological control, predatory mites, and integrated pest management (IPM). Temporal trends further revealed a pivot toward applied work on invasive pest systems. Co-citation analysis uncovered six foundational research clusters, while bibliographic coupling of 2021–2025 papers uncovered five active emerging subfields: landscape ecology and habitat manipulation, tri-trophic interaction mechanisms, high-impact invasive pest biocontrol, non-target risk assessment for introduced agents, and fall armyworm integrated management. We synthesize cross-cutting implications and outline future priorities—including AI-enabled rearing systems, functional biodiversity boosting, climate adaptation, and multifunctional landscape tuning. By consolidating historical progress and forward-looking directions, this framework empowers researchers, extension practitioners, and policymakers to scale sustainable pest management worldwide. Full article

Why do pandemics keep emerging despite decades of surveillance and response? Paleopathology, the study of disease traces in ancient remains, has been revolutionized by ancient DNA (aDNA) analysis and next-generation sequencing (NGS). Reconstructing pathogen genomes from archaeological material enables the identification of extinct lineages, the refinement of disease chronologies, and the characterization of long-term host-pathogen co-evolution. This provides context for public health challenges, including the emergence of pandemics and antimicrobial resistance (AMR). Infectious diseases are increasingly understood as complex phenomena arising from biological, ecological, and sociopolitical forces. Integrating paleopathology, aDNA, and paleomicrobiology supports a deep-time syndemic framework, revealing how recurring biosocial drivers have structured infectious disease risk throughout history. Ancient resistome studies demonstrate that AMR predates modern antibiotic use, reframing resistance as an intrinsic ecological feature rather than solely a modern phenomenon. Coronavirus disease 2019 (COVID-19) reaffirmed how infection intersects with chronic disease, health system fragility, and social inequities. This review highlights how integrating evolutionary perspectives into One Health shifts surveillance from a reactive approach to upstream risk mitigation and spillover prevention. Full article

Anthropogenic pollution may impose additional pressure on European populations of large protected carnivores due to the systemic toxicity of contaminants such as cadmium, lead, and radiocaesium (¹³⁷Cs). Our aim was to carry out ¹³⁷Cs, radiopotassium (⁴⁰K), and stable element distribution analysis through seven tissues of grey wolves (Canis lupus) from temperate forests of Croatia using ultra-low background gamma-ray spectrometry and ICPMS, respectively. In addition, radiolead (²¹⁰Pb) massic activity was quantified in femoral bone. The massic activity of ¹³⁷Cs in the heart, kidney, liver, spleen, lungs, and femoral bone (in decreasing order) ranged from 9–61% relative to muscle and showed strong inter-tissue correlations. However, correlations between radionuclides and their stable analogues in wolf tissues indicated considerable uncertainty in the use of stable element data for radiological risk assessment. In addition, concentration ratios (CR_{whole organism-soil}) derived from stable element data should be applied with caution when radionuclide data are lacking. Overall, radionuclide activities and element levels not subject to homeostatic regulation in grey wolves were comparable to or lower than those reported for other populations, particularly those from sub-Arctic regions. Despite being apex terrestrial predators, wolves inhabiting temperate ecosystems do not currently appear to be at risk of adverse health effects from exposure to the most relevant inorganic anthropogenic pollutants. Full article

Introduction: Delirium in older adults is strongly associated with and can predate dementia. While GLP-1 receptor agonists (GLP-1 RAs) may provide neuroprotective benefits, their role in reducing dementia risk among older patients with type 2 diabetes mellitus (T2DM) and prior delirium is unclear. This study compares the effectiveness of GLP-1 RAs and metformin in preventing dementia among patients with a history of delirium using an extensive healthcare database. Methods: A retrospective cohort study was conducted from 2005 to 2025 using data from the TriNetX Global Federated Research Network. We identified adults aged 65 and older with T2DM and delirium, who received either GLP-1 RAs (exposure) or metformin (control). Propensity score matching (PSM) was performed. We determined dementia outcomes and all-cause mortality using Kaplan–Meier survival curves, Cox proportional hazards models, and estimated odds ratio (OR). Subgroup analyses were conducted by age, sex, race, body mass index (BMI), and dementia types. Results: In a study involving 23,980 patients treated with GLP-1RAs and 23,980 matched patients treated with metformin, the mean age was 74 years, with 53% being female. The use of GLP-1RAs therapy was associated with a significantly lower risk of dementia compared to metformin among adults aged 65 years and older with T2DM with delirium with the adjusted hazard ratio (AHR) for dementia was 0.778 [95% confidence interval (CI): 0.736–0.822 p < 0.0001], and OR was 0.617 (95% CI: 0.582–0.655 p < 0.0001). The reduction in dementia risk varied by age, race, BMI, and dementia type. We observed a time-dependent decrease in mortality risk with GLP-1 RA users. Conclusions: In older adults with T2DM and delirium, GLP-1 RA therapy was associated with a reduced risk of dementia compared with metformin. Variations in subgroups suggest individualized treatment. Prospective randomized controlled trials are needed to confirm these findings and clarify differential effects across various subgroups. Full article

The growing popularity of ecotourism is increasing human–wildlife interactions in coral reef ecosystems. Although often considered benign, interactions with humans can alter essential antipredator responses. Reef fish exposed to humans often modify their antipredator behavior. Prior work has shown that fish respond differently in marine protected vs. non-protected areas (MPAs), but it remains unclear whether these differences stem from protection status or differences in human presence. We studied dusky damselfish (Stegastes nigrican) antipredator behavior across three sites separated by MPA status and human activity. We also investigated how different durations of short-term exposure to snorkeler presence influenced risk assessment across these sites. We quantified antipredator responses using: (1) the proportion of time fish were displaced from their territory during different durations of snorkeler exposure, (2) post-treatment flight initiation distance (FID), and (3) latency to return after fleeing. Human presence explained more variation than MPA status in all metrics. Fish from reefs with high human presence remained in their territories longer during treatments, had shorter FIDs, and returned faster after fleeing. Our findings suggest that snorkeling induces immediate behavioral changes and alters risk assessment following exposure in damselfish, potentially compromising fitness-promoting behaviors and predation avoidance. Full article

Marine organisms that episodically aggregate near coastal nuclear power plant water intakes pose a substantial risk to cooling water security. Predicting the spatial distribution of such high-risk species remains challenging because their occurrence is shaped not only by environmental conditions but also by complex trophic interactions. In this study, we model the habitat distribution of three high-risk nektonic species, Dotted gizzard shad (Konosirus punctatus), Japanese swimming crab (Charybdis japonica) and squid (Loligo sp.), in the cooling water intake area of a coastal nuclear power plant in eastern Liaodong Bay using generalized linear models (GLMs) and joint species distribution models (JSDMs). Based on summer surveys conducted in 2024–2025, we explicitly incorporated trophic linkages among target species, their prey, and predators within JSDMs. Model performance was evaluated using cross-validation based on AUC, RMSE, and coefficient of determination (R²). Our results indicate that water depth was the dominant environmental driver for all three species, while chlorophyll-a concentration and distance to the intake exerted species-specific effects. By incorporating interspecific trophic associations and environmental responses, JSDMs showed consistently improved predictive performance relative to GLMs, with approximately 1.5-fold higher R² values and 10–30% lower RMSE, while offering enhanced ecological interpretability. The models revealed strong positive associations between target species and both lower-trophic prey and higher-trophic predators, suggesting that top–down and bottom–up processes jointly regulate aggregation dynamics. This study demonstrates that integrating trophic interactions into species distribution modeling substantially improves predictions of high-risk marine species near coastal infrastructure and provides an ecological basis for proactive management of cooling water intake systems. Full article

The Spur-thighed tortoise (Testudo graeca) is a long-lived terrestrial reptile listed as ‘Vulnerable’ on the IUCN Red List and protected under CITES Appendix II. As an ecosystem engineer, it plays a vital role in Mediterranean landscapes, yet it frequently faces anthropogenic pressures in urban environments. This study provides an ecological and ethological assessment of a captive T. graeca population (n = 42) in the historical Münire Madrasa Handicrafts Bazaar in Kastamonu, Türkiye. The methodology integrated spatial carrying capacity modeling (Boullon model), systematic ethogram-based observations (120 h), and ethnozoological surveys (n = 200). Spatial analysis revealed that the population exceeds the corrected Real Carrying Capacity (RCC ≈ 10) by four times (Overcapacity Index: 4.2) within the 70 m² area. Ethological findings documented chronic stress, with stereotypic pacing (H1) occupying 32% of the time budget, alongside a significant loss of anti-predator mechanisms due to anthropogenic habituation (İ1). While stakeholders (100%, 95% CI: 98.1–100%) perceive the tortoises as cultural symbols of abundance, the biological reality indicates severe welfare risks, including potential metabolic bone disease from a monotonous anthropogenic diet and a disrupted Ca:P ratio. The site is categorized as a ‘High-Constraint Interaction Zone’. We propose a management transition toward a monitored ‘Urban Wildlife Education Station’ to align local cultural values with international animal welfare and conservation standards. Full article

The American chestnut (Castanea dentata (Marsh.) Borkh.) was a foundation species whose loss reshaped eastern North American forests. Ongoing breeding with blight-resistant Chinese chestnut (Castanea mollissima Blume) represents the leading strategy for its restoration. However, breeding programs have focused almost exclusively on pathogen resistance, leaving susceptibility to native seed predators unexamined—a critical gap, because nut production underpins the ecological function that restoration seeks to recover. Here, we investigate how hybridization level affects infestation by the lesser chestnut weevil (Curculio sayi (Gyllenhal, 1836)), monitoring 25 genetic lines across four genetic categories (Chinese, F₁, backcross, and American) for larval emergence, weight loss, damage, and emergence timing over eight weeks. Hybridization dramatically altered susceptibility: F₁ hybrids were the most susceptible category. No larval emergence was observed from American chestnuts, and backcross hybrids remained substantially susceptible despite three–four generations of backcrossing. These results expose a fundamental trade-off for restoration: blight resistance derives from the Chinese genome, whereas weevil resistance appears to be associated with the American genome. Backcross lines bred for blight resistance retain weevil susceptibility, and F₁ hybrids risk functioning as pest sinks that amplify local weevil populations. Incorporating weevil resistance screening into breeding programs could help us to ensure that restored chestnuts can fulfill their historical role as mast-producing foundation trees. Full article

Mercury (Hg) bioaccumulation in freshwater fish represents a major pathway of human exposure, particularly in cascade reservoir systems where hydrological retention and legacy contamination can enhance methylmercury (MeHg) formation and trophic transfer. This study quantified total mercury (THg) concentrations in seven tissues of seven fish species from the Arda River cascade (Bulgaria). Multi-tissue measurements were integrated with morphometric predictors, multivariate statistical analyses, and combined deterministic and probabilistic human-health risk assessments. Muscle and liver contained the highest THg concentrations, whereas gills and gonads exhibited the lowest levels. Predatory species and larger individuals accumulated significantly more Hg, reflecting trophic magnification and size-dependent exposure. A longitudinal gradient across the cascade reservoirs suggests hydrological retention effects influencing mercury distribution. Species- and tissue-specific size–Hg relationships further indicate heterogeneous bioaccumulation dynamics among taxa. Risk assessment indicated acceptable exposure for adults and pregnant women at average consumption (140 g·week⁻¹), but elevated exposure for children consuming high-Hg predators. Monte Carlo simulations (N = 30,000) revealed upper-tail risks, while Safe Weekly Intake thresholds provided species-specific consumption limits. These findings highlight the value of integrating multi-tissue monitoring with probabilistic risk modelling to support evidence-based fish-consumption advisories in contaminated freshwater systems. Full article

The Black Sea is highly vulnerable to environmental degradation, making the evaluation of contaminant transfer within its food webs essential for ecosystem protection, sustainable resource management, and human health risk assessment. Marine organisms accumulate contaminants through three main processes: bioconcentration (direct uptake from the abiotic environment), biomagnification (trophic transfer through consumption of contaminated prey), and bioaccumulation, which integrates contaminants from all exposure pathways. Despite numerous studies reporting contaminant concentrations in Black Sea waters, sediments, and biota, integrated analyses of trophic transfer within both pelagic and benthic food webs in the Romanian coastal sector remain limited. This study assessed the bioamplification of heavy metals—HMs, persistent organic pollutants—POPs (OCPs, PCBs) and polycyclic aromatic hydrocarbons—PAHs along the main pelagic and benthic food webs in the Romanian coastal sector, based on concentrations measured in representative invertebrate and fish species. The results revealed a compartment-driven contamination pattern, with the benthic food web functioning as an important reservoir and transfer pathway. Heavy metals showed variable and context-dependent trophic transfer, with selective amplification for Cu and Ni in some benthic links, trophic dilution or neutral transfer for Cd and Pb, and more consistent retention for Cr. In contrast, several PCB congeners showed clear biomagnification, particularly in benthic predator–prey relationships. PAHs displayed compound-dependent trophic transfer, with more pronounced amplification in benthic pathways. Overall, biomagnification was stronger for organic pollutants, particularly PCBs, than for heavy metals. The study contributes to two United Nations Sustainable Development Goals (SDGs): SDG 14 (Life Below Water) and SDG 12 (Responsible Consumption and Production). Full article

The background modification of ecosystems affected by fire can cause black or dark colours in animals to become adaptive, providing better protection against visually oriented predators. We surveyed fire-prone Mediterranean woodlands to describe the behaviour, position and background characteristics of the black cicada Tibicina quadrisignata Hagen, 1855 found in recently burnt and unburnt trees. A human detectability test, using cicada pictures in natural backgrounds taken during the fieldwork, was used to assess detection risk. Most cicadas found were solitary males uttering courtship song. Many cicadas flew when approached, with 82% of flight initiation distances being less than 3 m and half of the flights being less than 30 m. Cicadas favoured sunny locations in early morning, and shady sites as the temperature increased. Fire altered fine-scale microhabitat use by cicadas, since cicadas were found in 71% thicker stems and at 14% lower height on the tree, in burnt trees, in relation to unburnt trees. Generalised Linear Mixed Models (GLMMs) revealed a negative fire effect on cicada detection by human test participants. The probability of detection fell from 0.62 in unburnt backgrounds to 0.48 in burnt backgrounds, while the time needed for detection did not change between burnt and unburnt sites. Overall, these results show that T. quadrisignata cicadas adjust their substrate use after fire and are less detectable on burnt backgrounds. Real predation risk, however, also depends on thermoregulation-associated exposure, courtship song activity and predator densities. Full article

Parasitoids use different signals to locate their hosts, and these signals can modulate their behavioral decisions. Thus, patch selection and foraging in patches with different characteristics depend on their ability to gather and use such information efficiently. In this study, we evaluated whether the parasitoid Eretmocerus eremicus (Hymenoptera: Aphelinidae), a natural enemy of Trialeurodes vaporariorum (Hemiptera: Aleyrodidae) on tomato plants (Solanum lycopersicum), uses scent cues to select and forage in patches that differ in host density and predation risk. Using choice bioassays in a wind tunnel under a continuous airflow, we recorded selection patch and selection time, as well as foraging parameters, including residence time, oviposition events, and attacks. Our results show that E. eremicus discriminated between sites with and without hosts using scent cues, but discrimination between patches with different host numbers was not detected under our assay conditions. It also distinguished between patches with maximum risk and those without risk, but not between subtle differences in risk. These findings suggest that E. eremicus, responded mainly to contrasting olfactory cues rather than to subtle odor differences. From an applied standpoint, our results motivate deeper investigation into how host- and predator-associated olfactory cues could fine-tune parasitoid deployment in biological control. Full article