Aquatic Conservation: Marine and Freshwater Ecosystems
○ Wiley
Preprints posted in the last 30 days, ranked by how well they match Aquatic Conservation: Marine and Freshwater Ecosystems's content profile, based on 12 papers previously published here. The average preprint has a 0.01% match score for this journal, so anything above that is already an above-average fit.
Srikanth, Y. V.; Pulla, S.; Namboothri, N.; D'Souza, E.
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Blue Economy models position aquaculture as a key pathway to securing global food security. Species selected for aquaculture typically show rapid growth, high stress tolerance and fast biomass accumulation, but these same traits may increase their potential to become invasive when introduced beyond their native range. We investigated the invasion history and current status of the commercially important red seaweed Kappaphycus alvarezii in the Palk Bay-Gulf of Mannar region of India. This is one of the worlds largest cultivation hubs, a climatically vulnerable marine biodiversity hotspot, and one of the three regions to report invasion. We combined in-water surveys, interviews with wild seaweed collectors, and a review of published literature to reconstruct the history of invasion and assess current status. Invasion has declined substantially, with interviews indicating that the disappearance of invasive populations began around 2014. We discuss several non-mutually exclusive explanations for this decline, including climate change, loss of coral substrate, herbivory, and reduced vitality of the seaweed. Although the decline in invasion is encouraging for coral reefs, our findings raise questions about the ecological and socioeconomic consequences of introducing non-native aquaculture species under Blue Economy initiatives, particularly in ecologically sensitive regions vulnerable to climate change.
van Ooijen, R.; Buring, R.; Cornelius, A.; He, H.; van Oevelen, D.; Thieltges, D. W.; Hammoud, C.
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The impact of invasive species on marine ecosystems is rapidly increasing, where they often outcompete native species in the absence of natural enemies. The parasite release hypothesis states that the success of invasive species relates partly to the loss of natural parasites during introduction and lower susceptibility to native parasites. Barnacles are highly successful invaders due to broad environmental tolerance and dispersal via shipping, but whether parasite release also participates in this success remains unknown. In this study, we analyse parasite infection patterns in native and invasive barnacles in the Wadden Sea by surveying communities across tidal zones. Additionally, year-round molecular monitoring of larval stages and a literature review were used to track the distribution of the invasive Pacific barnacle Balanus glandula in Europe and document its appearance in the Wadden Sea. The long-established invasive Austrominius modestus dominated the high and middle intertidal zone, whereas native species (Balanus crenatus and Amphibalanus improvisus) prevailed in lower zones. Native and invasive barnacles differed in parasite infection frequency (mostly cestodes and trematodes). The native Semibalanus balanoides had the highest prevalence (27%), followed by the invasive A. modestus (11%), and no infections were found in B. glandula. Lower parasite prevalence in invasive barnacles is consistent with the hypothesis that parasite release supports invasion success. In the absence of competent parasites, B. glandula could impact native barnacles through competition. Continued monitoring of B. glandula is recommended to track its distribution, interactions with native species, and parasite acquisition, providing further insight into the parasite release hypothesis.
Monaghan, A. I. T.; Griffiths, N. P.; Sellers, G. S.; Lawson Handley, L.; Nunn, A. D.; Hänfling, B.; Macarthur, J. A.; Wright, R. M.; Cattaneo, M.; Bolland, J. D.
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Context Pumping stations pose a threat to fish globally through land use change, habitat fragmentation and entrainment risk, with the catadromous and critically endangered European eel particularly impacted. Objectives/methods Establish, model, assess and understand the present-day distribution of European eel and resident fishes in 152 pumping station catchments in a once extensive wetland (The Fens) using eDNA metabarcoding (855 samples over two and half years), with specific focus on anthropogenic influences on hydrological connectivity and habitat quality. A removal survey design maximised confidence in negative results while minimising time and consumable costs. Results Eel occurrence upstream of pumping stations was low (occupancy = 28.3%) and positively associated with catchment area, fish species richness and natural hydrological connectivity (gravity drainage or flooding) and negatively associated with distance from the tidal limit. Fish species richness replaced catchment area and improved model performance, potentially acting as a biotic indicator of habitat quality and connectivity. Pumped catchments with manually operated upstream water transfers had reduced eel presence, potentially linked to the direction of water flow or the timing of operation. By contrast, fish species richness increased in these catchments during summer, suggesting displacement into unsuitable long-term habitats. Physical habitat maintenance had no detectable effect on eel occurrence or fish species richness. Conclusions This study provides the first landscape-scale assessment of European eel distribution and drivers of occurrence in pumped river catchments. The highly novel and comprehensive insights have implications for European eel conservation as well as infrastructure and catchment management, including compliance with legislation (EC Regulation No. 1100/2007).
Muffett, K. M.; Sporre, M.; Miglietta, M. P.; Eytan, R.
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Ranges of small benthic fauna are notoriously difficult to assess. In some of these cases, modern eDNA methods can shed light on species occurrence. Here we conduct an exploratory study on the fish eDNA recoverable from the gastrovascular cavities of the easy-to-sample pore water siphoning benthic invertebrate, Cassiopea, across six sites within the Florida Keys. Twenty-seven fish 12S identities were recovered from water samples, two from sediment samples, and seventeen from Cassiopea gut swabs. In total, thirty-two different species were identified from nineteen families, including one shark species (Ginglymostoma cirratum), and five species of cryptobenthic reef fishes (f: Gobiidae, Labrisomidae). Additionally, five species were identified from medusae samples that were not recovered in water or sediment samples. The species identities recovered may provide insight into the fish in direct proximity to Cassiopea assemblages, as well as indicate that Cassiopea may accrue disproportionate eDNA from cryptobenthic reef fish compared to surrounding environmental samples. The unorthodox sampling technique of using eDNA recovered from jellyfish stomachs yields another avenue for epibenthic community data acquisition.
Tomoleoni, J. A.; Yee, J. L.; Seacord, E.; Staedler, M. M.; Hatfield, B. B.; Carswell, L.; Fujii, J.; Bentall, G. B.; Konrad, L.; Young, C.; Tinker, M. T.; Bowen, L.
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The southern sea otter (Enhydra lutris nereis) population at San Nicolas Island, California, has been monitored annually since the translocation of 140 sea otters to the island was completed in 1990. Monitoring efforts have varied in frequency and method across years. In 2017, in accordance with the National Defense Authorization Act for Fiscal Year 2016, the U.S. Navy and the U.S. Fish and Wildlife Service formally initiated a sea otter monitoring and research plan to determine the effects of military readiness activities on the growth or decline of the southern sea otter population at San Nicolas Island. The monitoring program, at its basic level, includes quarterly seasonal surveys of population abundance, distribution, and foraging activity. This report presents data from the program with a focus on the recent three years from winter 2023 through winter (February) 2026. From 2023 to 2026, we measured an 8.1-percent per annum decrease in population abundance (95-percent confidence interval =1.1-14.6 percent), with 106 total individuals counted as of February 2026. Historically, sea otter habitat usage at San Nicolas Island was concentrated on the west end of the island. Between 2017 and 2019, we observed increased seasonal usage of the north and south sides of the island, and in 2020-2022, a large (approximately 30-40 individuals) group of sea otters (raft) took up residence off the east end. During 2023-2026 the east end raft disappeared, and sea otters returned to their historical habitat usage patterns at the west end of the island. Foraging data were collected from summer 2023 to winter 2026 on a total of 461 foraging dives in 32 foraging bouts, and the majority of identified prey on successful dives (n=325) were sea urchins (124) followed by snails (48), bivalves (41) and crabs (23). One lobster and one octopus were also identified among the sea otter prey items. We combined these data with data from 2020-2022 to estimate overall energy intake rates that averaged 7.7 kilocalories per minute (95-percent credible interval =6.6-9.1 kilocalories per minute). These results can be useful to the planning of future monitoring and research of sea otters at San Nicolas Island.
Chopra, M.; Salguero-Gomez, R.; Stevens, G. M. W.; Rowlands, G.; Karnad, D.; T., M.; Fernando, D.; Davis, K. J.
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As anthropogenic threats have intensified over the past 500 years, we find ourselves in the midst of a sixth mass extinction, with continued losses of biodiversity threatening ecosystem stability. This biodiversity loss has caused species extinctions across taxa, and placed several others at high risk of functional extinction. These disturbance-driven impacts represent one of the most acute biodiversity crises facing global marine systems. Species exhibiting slow life histories characteristically have low resilience to disturbance. Here, we assess the risk of functional extinction and identify policy pathways for population recovery of the slow-living, Critically Endangered elasmobranch, the spinetail devil ray (Mobula mobular). We develop a stochastic, state-structured Integral Projection Model (IPM) parameterised with demographic data collected from fishery landings data in India, the world's largest mobulid fishery, and supplemented with data on vital rates from published literature. Using the IPM, we estimate that the population is declining at approximately 12% annually, experiencing substantial limiting pressure from fisheries overexploitation and failing to approach its biological maximum growth potential. Our results indicate that populations of M. mobular will be at high risk of functional extinction if 'business as usual' harvest scenario persists for another decade. We further show that long-term population recovery is only possible if survival increases significantly across all size classes, especially among large reproductive females, alongside a concurrent increase in fecundity. We conclude that no single policy measure is sufficient to recover population of M. mobular along the southeastern coast of India. Instead, combined protection through maximum bycatch mitigation and protection of nursery areas in no-take zones will be required for population recovery. This research demonstrates that recovery of overexploited populations often requires integrated resource management across life stages, and that the Critically Endangered M. mobular warrants urgent conservation action to avoid functional extinction.
Berlik, E.; Dantzker, M. S.; Delikaris-Manias, S.; Duggan, M. T.; Rice, A. N.
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Coral reef monitoring needs scalable, non-invasive tools to complement resource-intensive traditional survey methods. Passive Acoustic Monitoring (PAM) offers a promising supplement, but its effectiveness is limited by the difficulty of attributing recorded sounds to species outside of previously well-characterized taxa. Using Omnidirectional Underwater Passive Acoustic Cameras (UPAC-360), we identified sounds from 31 reef fish species across 14 families on the Kona coast of Hawaii Island, including 13 not previously documented as soniferous. By releasing video and audio specimens, we have created the largest open-access collection of in-situ reef fish sounds to date for the Pacific. A subset of acoustically distinctive taxa--such as Hawaiian Dascyllus (Dascyllus albisella), Lei Triggerfish (Sufflamen bursa), soldierfishes (Myripristis spp.), wrasses, and herbivorous grazers--were identifiable in PAM recordings through manual acoustic and spectrogram review. Through identifying particular sounds linked to species with different ecological roles, these sounds have the potential to serve as indicators of reef function to increase the information and value coming from PAM surveys of Hawaiian and Pacific coral reefs.
Lewis, R.; Dodd, K.; Macadam, C.; Matthews, I.; Pulver, S. R.
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Freshwater ecosystems in Scotland are increasingly threatened by multiple interacting stressors, including pollution, hydrological alteration, land use change, and climate-driven pressures. Scotland's rivers are amongst the most physically diverse and dynamic in the UK, contributing significantly to the country-s economy and natural heritage. Monitoring 125,000 km of waterways presents an issue, with limited funding and capacity of environmental agencies creating an environmental monitoring deficit at a time when robust data are essential for delivering national and global biodiversity targets. Citizen science offers a scalable, community driven approach to strengthening environmental evidence. This study evaluates the development, implementation, and outcomes of Guardians of our Rivers (GooR), a nationwide citizen science programme using macroinvertebrate-based river health assessments based on the Anglers' Riverfly Monitoring Initiative (RMI) established by the Riverfly Partnership. Between 2022 and 2025, GooR trained more than 850 volunteers, established 123 monitoring sites across Scotland, and generated over 860 surveys-surpassing the previous 16 years of aquatic invertebrate monitoring efforts. Standardised field training, full equipment provision, and structured support enabled high-quality data collection across diverse catchments. The establishment of nationally applied trigger and target thresholds created a consistent mechanism for detecting ecological deterioration and ensured that verified trigger breaches (n = 39 in 2025) resulted in formal investigation or follow-up. Analysis of national abundance patterns revealed ecological and biogeographic trends across the eight RMI taxa, confirming data sensitivity to habitat differences, water quality, and regional pressures. A detailed case study of the Lothian Esk catchment demonstrated the programme's capacity to detect seasonal macroinvertebrate dynamics and site level ecological trajectories over time. Overall, GooR illustrates how well-designed and well-supported citizen science can deliver high resolution spatiotemporal datasets, enhance early warning systems, empower communities, and make a meaningful contribution to promoting river health. Importantly, GooR forged a working partnership with Scottish Environmental Protection Agency (SEPA) that allowed communities to not only gather data but also transformed the way citizen science is recognized as contributing to freshwater conservation. Continued investment and long-term support will be essential to sustain these gains and realise the full potential of citizen-driven freshwater stewardship.
Rijnsdorp, A. D.; Bennema, F. P.; Veenstra, F.; Eigaard, O. R.; Thomassen, J. A.-C.; McLaverty, C.
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Bottom trawls have been used for centuries, yet studies of their impact on marine ecosystems have largely been restricted to recent decades. Here, we reconstruct fishing effort for the international trawler fleets in the North Sea from the age of sail to early steam trawling, by synthesising historical data describing vessel numbers and specifications, gear dimensions, fishing grounds, and operational characteristics. The trawler fleet increased from ca 800 sailing vessels in the 1820s to ca 3500 at the peak in sail trawling in the 1880s. Subsequently, steam trawling fleets emerged, increasing to almost 2000 vessels in the 1910s, while sailing fleets declined. Trawling grounds, covering ca 7% of the North Sea in 1820s, expanded from coastal to offshore grounds, reaching ca 25% in the 1880s, and 46% in the 1910s after the transition to steam trawling. Using a hydro- and aerodynamic approach to model the wind conditions required for sail trawling, we show that about 55% to 80% of the time at sea was suitable for trawling, providing a new quantitative basis for estimating historical fishing effort. The surface area swept by the trawl per year increased from 35,000 km2 in 1820s to 225,000 km2 in 1880s and 500,000 km2 in 1910s, corresponding to ca 60% of present levels. The trawling intensity (swept area ratio) varied between 0.9-1.7 year-1 in the era of sail, increasing to ca 2.0 in the 1910s. The trawling footprint (unique area trawled) increased to 160,000 km2, about half the present level.
van der Steeg, E.; Humanes, A.; Bythell, J. C.; Edwards, A. J.; Golbuu, Y.; Lachs, L.; Miller, M. W.; Guest, J. R.
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Sexual coral propagation is an emerging technique capable of producing large numbers of corals for coral transplantation and reef rehabilitation. In contrast to asexual coral propagation, sexual propagation increases genotypic diversity and can be used for selective breeding to enhance coral heat tolerance or other desirable traits. However, implementation at meaningful ecological scales is hindered by high mortality during early life stages, high costs associated with nursery rearing facilities, and labour-intensive outplanting methods. To overcome these issues, we developed the CoralAssist Plug (CAP), a ceramic device designed for the rapid and cost-effective outplanting of sexually propagated corals in large numbers that maximises post-outplant survivorship. CAPs combine three important functional features: 1) built-in microrefugia to protect juvenile corals from grazing, 2) a relatively small size, 3 by 1 cm, that is easy to handle and stack efficiently without compromising the survivorship of corals, and 3) a hole in the middle that facilitates handling and attachment. CAPs were settled with Acropora aff. digitifera and outplanted to a reef crest after 1 to 6 months of ex situ nursery rearing. A 3-person dive team was able to outplant ~120 CAPs in one 90-minute shallow dive (just over 2 minutes per CAP per person). With longer nursery durations of 6 months, it was possible to achieve 36 % yield (i.e., the proportion of devices with a surviving coral) 4-years post-outplant. With nursery durations shortened to 1 month, we were able to attain 24 % yield 3-years post-outplant. Microrefugia significantly enhanced post-outplant survivorship leading to an 11 % increase in yield 4 years post outplant compared to devices without microrefugia. Outplanted corals that had reached adult size, were self-attached and were reproductively mature after 4 years. Our results suggest that CAPs can play a meaningful role in reef rehabilitation by efficiently introducing sexually propagated corals into natural populations with clear applications to assisted evolution techniques, such as selective breeding.
Arnold, K. M.; Reyes-Corral, W. D.; Howard, O.; Graca, C.; Aguirre, W. E.
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This study investigates the impact temperature-induced vertebral anomalies have on the C-start escape response of Astyanax mexicanus, a model species in evolutionary developmental biology. Employing three temperature treatments to induce varying degrees of skeletal anomalies, we assessed their effects on key swimming performance metrics including, C-start time, curvature coefficient, head displacement distance, and displacement velocity. Through the use of linear mixed models and generalized linear mixed models, our results reveal that specific anomalies such as vertebral fusions and anomalous haemal and neural spines affected the curving ability of C-start escape responses. However, these did not negatively impact other performance parameters, with velocity, distance, and response time showing no significant impacts from any anomaly types, when assessed individually. This suggests a complex interplay between structural deformities and compensatory physiological mechanisms that maintain functional performance. Other variables measured had a stronger and significant impact on swimming performance, including standard length, vertebral number, and temperature treatment, which influenced escape speed, curving ability, and overall locomotor performance. Our findings challenge conventional perceptions about the debilitating impact of vertebral anomalies, indicating that many affected fish can still effectively perform escape maneuvers critical for survival.
Nordström, E.; Rosbakh, S.; Hoppenreijs, J. H. T.
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Flow regulation for hydropower production affects stream ecosystems through decreased connectivity and changed timing and magnitude of flows. Hydropeaking, a form of regulation in which infrequent large peak flows are replaced with frequent small peaks, increases riparian erosion and causes water and drought stress for riparian vegetation. Hydropeaking is likely to affect soil seed bank (SSB) formation and composition, while SSBs are important sources of self-restoration should a systems flow regulation be relaxed. We tested how hydropeaking intensity affects the size and composition of SSBs, including the functionally important group of large graminoids, and by calculating Ellenberg values for Moisture, Light and Soil disturbance. SSB samples were taken at 15 riparian zones across central and northern Sweden. Each site was regulated, but sites differed in their hydropeaking intensities. SSBs were subjected to a seedling emergence experiment, from which over 700 seedlings from 53 taxa emerged. We found that hydropeaking intensity affects the composition of soil seed banks on multiple levels. Seedling density was negatively correlated with hydropeaking intensity at the sites where samples were taken. SSB richness varied (two to eighteen species per site) and was not affected by hydropeaking intensity. The proportion of large graminoids in the seed bank showed a near-significant decrease with increasing hydropeaking intensity, and community-weighted means for Moisture, Light and Soil disturbance increased (non-significantly) with increasing intensity. Our results suggest that riparian SSBs, should flow regulation be relaxed or ceased, are not sufficient for self-restoration of functional riparian vegetation. Seeds of large graminoids and species that are tolerant to drought in the germination stage are less present in riparian SSBs of heavily-regulated streams. Supply of seeds of these groups, or even planting, may need to be considered when changes in flow management are implemented. HighlightsO_LIHydropeaking negatively affects riparian soil seed banks (SSBs) in Sweden C_LIO_LISSB size slightly decreases with hydropeaking intensity, but richness does not change C_LIO_LIThe proportion of large graminoid seeds in SSBs decreases with hydropeaking intensity C_LIO_LIRiparian SSBs from less-impacted sites have most potential for self-restoration C_LI
Gerard, J.; Branger, L.; Huyghe, F.; Kochzius, M.; Otwoma, L.; Bergacker, S.; op't Roodt, L.; Rumisha, c.; Di Bella, L.
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Coral reef fish assemblages are widely used as indicators of ecosystem condition, yet manual annotation of underwater video remains a major bottleneck for scalable biodiversity monitoring. Despite rapid progress in automated detection, ecologically realistic and publicly available datasets remain scarce, particularly for the Western Indian Ocean. Here, we present WIO-ReefFish, a reef fish detection dataset derived from diver-operated line-intercept transects and designed for ecological monitoring under natural survey conditions. WIO-ReefFish comprises 1,000 ultra-high-definition images (3840 $\times$ 2160 pixels) and 6,768 exhaustive bounding-box annotations spanning 24 taxonomic categories, thereby preserving full-frame assemblage structure in complex reef scenes. We also establish a standardized benchmark across nine object detection models under two complementary protocols: class-aware detection and class-agnostic fish localization. Detection performance was consistently higher under the class-agnostic protocol. The best-performing model (RT-DETR) improved from 0.48 mAP50 in the class-aware setting to 0.70 mAP50 when taxonomic constraints were removed, indicating that taxonomic discrimination remains substantially more challenging than fish localisation in reef imagery. Spatially independent evaluation revealed a pronounced generalisation gap, particularly for taxonomic detection, whereas class-agnostic fish localisation remained substantially more robust across transects and countries. Together, these results establish WIO-ReefFish as a realistic benchmark for automated reef fish detection and provide a foundation for more robust computer-vision tools in coral reef biodiversity monitoring. The WIO-ReefFish dataset and associated benchmarking resources are publicly available.
Vapillon, L.; Delva, S.; Bonafont Castelles, M.; Assis, J.; Strubbe, D.; Adriaens, T.; De Clerck, O.; Vranken, S.
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Biological invasions are a major driver of global change, reshaping ecosystems and threatening biodiversity worldwide. Anticipating where invaders will establish and where they will exert the strongest ecological impacts are key challenges for early detection and targeted management. Although Species Distribution Models (SDMs) are widely used to forecast biological invasions, they often provide uncertain estimates of establishment ranges and limited insight into invader performance, making it difficult to anticipate ecological impacts. Here, we address these limitations by integrating physiological information on invader performance with SDMs to identify regions of high invasion risk. Using the brown alga Rugulopteryx okamurae, one of the most prominent marine invaders in Europe, we first test alternative hypotheses of northern establishment limits: (i) a cold-survival constraint driven by winter temperatures and (ii) a growth constraint derived from the species' thermal performance. To identify the more likely scenario, we combine cold-tolerance experiments with seasonal growth comparisons between the invader and a native macroalga Dictyota dichotoma, whose established distribution allows physiological performance to be directly related to realised presence. Finally, we project seasonal growth of the invader across the predicted establishment range as a proxy for biomass accumulation and potential ecological impacts. Our results indicate that northern limit in Europe will be more likely constrained by winter survival rather than growth, extending the potential establishment range of Rugulopteryx to mid-Norway. In contrast, the highest impacts are likely to remain concentrated in southern Europe, where thermal conditions sustain high year-round growth. Overall, our approach illustrates how understanding the physiological response of invaders to their environment can improve the interpretation of SDM outputs and help identify areas at greatest risk of impact within their potential establishment range.
Tchatakoura, A.; Buysse, M.; Setier Rio, M.-L.; Roux, O.; Loiseau, C.; Aviles, A.
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Background: Microplastics have been detected in many freshwater ecosystems, including stagnant waters where mosquito larvae develop. Larvae are therefore exposed to microplastic pollution, which may affect their life history traits or microbiota along with immune gene expression. However, these effects have never been tested in mosquitoes, despite their major public health importance as vectors of numerous pathogens. Method: We exposed mosquito larvae, from hatching to adult emergence, to four concentrations of polyethylene microplastics (MPs): 0, 60, 200, and 600 MPs/mL. Fourth-instar larvae and newly emerged adult females were collected for each treatment. To investigate the effects of MPs on gene expression and bacterial microbiota, RNA sequencing and 16S metabarcoding approaches were performed on three biological replicates for each developmental stage. Results: Microplastic exposure induced a non-monotonic dose-dependent transcriptomic response. In larvae, only a limited number of genes were differentially expressed (five to eight per concentration), with immune-related genes downregulated at both low and high concentrations. In adult females, the intermediate concentration (200 MPs/mL) elicited the strongest response with 14 differentially expressed genes (DEGs). Regarding the microbiota, microplastic exposure reduced bacterial diversity in larvae, with the lowest diversity observed at the highest concentration. However, no significant changes were detected in the microbiota of adult females. Conclusion: Overall, this study shows that adult females are affected by larval exposure to MPs (i.e. differential expression in immune-related genes) and warrants further studies in this field. This includes: 1) investigating further the effects of MPs on mosquitoes' populations (e.g. through multi-generational studies), 2) gaining more environmentally relevant knowledge on MP effects (i.e. using MPs with a biofilm and/or adsorbed pollutants) and 3) focusing on the effects of MPs on mosquitoes' vectorial capacities.
Tajudeen, T. T.; Ardon, M.; Tulbure, M.; Martin, K. L.
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Coastal forests are increasingly threatened by saturated soil and elevated salinity levels resulting from sea level rise, saltwater intrusion, and storm surges. In response to rising salinization and flooding, healthy coastal forests that rely on freshwater (both wetland forests and low-elevation upland forests) are transitioning into landscapes dominated by dead or dying trees, known as ghost forests. Situated among salt-tolerant shrubs and grasses, ghost forests eventually become marshes or open water. Here, our main objective was to quantify the dynamics and pathways of these forest landscape conversions, as well as the factors contributing to the changes, which is vital for understanding the progression of coastal ecosystem degradation and forecasting future changes. We focused first on identifying the best method to track forest landscape change by exploring the role of multiple remote sensing indices (i.e., multispectral, bi-seasonal, topographical, and phenological metrics) in enhancing the performance of deep learning models (convolutional neural networks, CNNs) for land cover classification in the coastal plain of North Carolina using surface reflectance of Landsat 8 and Sentinel-2 images. Then, we used the best available data (Landsat 8) to understand long-term change and identify patterns of land cover change from 1985 to 2021. Our study reveals that incorporating phenology and topographical indices enhances the separability of the ghost forests class from all other vegetation classes. In our assessment, the higher-resolution Sentinel-2 data (F1 Score = 96.3) outperformed Landsat images (F1 score = 93.4) for the 2021 co-available year. However, Landsat remains an important tool used due to its long-term data record. Therefore, we used Landsat to determine that 21% of forests were lost between 1985 and 2021, and that the rate of loss is increasing. Between 2010 and 2021, 23,876 ha of forest were converted to marsh, ghost forest, and shrub, which is 1.5 times higher than the 16,968 ha lost between 1985 and 2010. These conversions from forest to ghost forest and marshes were driven primarily by proximity to the channel, salinity, and the increasing rate of relative sea level rise (RSLR), which are the key environmental drivers of observed changes. By quantifying these changes, we highlight regions most vulnerable to environmental stressors, providing a basis for targeted conservation strategies.
Pershyn, N.; Nielsen, C. K.; Bastille-Rousseau, G.
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Gray fox (Urocyon cinereoargenteus) populations in the Midwestern USA have suffered precipitous declines in recent decades, yet they are relatively understudied. However, understanding survival and cause-specific mortality is vital for declining populations and the limited existing survival studies have been performed outside of the Midwest. We equipped 13 gray foxes in southern Illinois with GPS radio collars to investigate their survival and cause-specific mortality. We calculated the Kaplan-Meier 6- and 12-month survival rates to be 0.79 (95% CI: 0.57-1.0) and 0.53 (95% CI: 0.27-1.0), respectively. We recorded 4 mortalities: 1 disease, 1 gunshot, and 2 unknown causes. While our study has a small sample size, it contributes key information on a data-deficient mesocarnivore suffering from a population decline driven by undefined causes. We recommend further research into the survival and mortality of this elusive mesocarnivore.
Snedden, G. A.; Couvillion, B.; Schoolmaster, D. R.
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The tidal wetlands of Louisiana comprise about 25% of those found throughout the conterminous United States yet estimates of wetland loss rates in the region between 1932 and 2016 have exceeded 60 km2 yr-1. To mitigate further degradation and wetland loss in the region, a globally unprecedented $50B, 50-year plan for coastal Louisiana is driving restoration efforts, and demand exists from multiple stakeholders for regularly updated, regional-scale, accurate land cover information. We used machine learning (random forests; RF) and cloud computing to develop a new Landsat-based, marsh vegetation community geospatial dataset. The dataset depicts wetland vegetation community types defined in a previous study at annual (1985-2025) time steps at 30-m resolution. An RF algorithm was used to integrate training samples with feature variables derived from Landsat imagery, and the resulting geospatial data product achieved an overall correct classification rate of 78%. The approach for development of the land cover dataset presented here has potential for application in other coastal wetland habitats throughout the world.
Quijano, J. B.; Tayaban, K.; Baquiran, J. I. P.; Maala, G. J.; Requilme, J. N. C.; Sayco, S. L. G.; Dolorosa, R. G.; Cabaitan, P. C.; Conaco, C.
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Giant clams are some of the largest bivalve molluscs. They form a vital partnership with Symbiodiniaceae dinoflagellates that supply most of their energetic requirements. However, the factors that shape giant clam-associated photosymbiont communities remain unknown. Here, we profiled Symbiodiniaceae communities using ITS2 metabarcoding in eight giant clam species (Hippopus hippopus, H. porcellanus, Tridacna crocea, T. derasa, T. gigas, T. maxima, T. noae and T. squamosa) from 11 sites across the Philippine archipelago. Symbiodiniaceae community structure was shaped by an interplay between giant clam host and environment. Most giant clams were dominated by members of a single symbiont genus, with Cladocopium as the most prevalent, followed by Durusdinium and Symbiodinium. However, giant clam hosts also exhibited flexibility in their symbiotic partners that was evident across sites. Differences in giant clam-associated symbiont communities may contribute to differences in holobiont function and adaptability to variable environments. These findings deepen our understanding of giant clam-Symbiodiniaceae associations, offering a framework for predicting how giant clams may be affected by increasingly stressful reef conditions and, more importantly, informing strategies to improve mariculture and conservation practices.
Jogula, K.; Tata, R. P.; Sankati, J.; Gudapati, J.; M, Y.
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Investigating Changes Detection in Land Use and Land Cover Analysis of Opencast Singareni Coal Mine Area Using Remote Sensing and GIS Techniques was the focus of the current investigation. Change Detection Analysis for Land Use Land Cover over a decade frequency (2005-2015) of cultivated soils surrounding OpenCast Coal Mine areas namely Ramakrishnapur, Srirampur and Medipalli of Telangana State.AWiFS data of IRS Resoursesat Satellite images of 2005 and 2015 were taken for the detection of temporal variation in Land use/ Land cover due to open cast coal mining.The ability of remote sensing techniques to produce precise spatiotemporal statistics of LULC and its changes in the typical coal mining region has been demonstrated, in open cast coal mining per year was the highest at Ramakrishnapur (@ 300 ha / year) followed by Srirampur (@ 150 ha / year) and Medipalli (@ 100 ha / year).At Ramakrishnapur with the onset of mining there was considerable decrease in agricultural land, shallow water bodies and deciduous forests i.e., conversion of these land uses to mining was evident. Whereas, at other two mining sites (Srirampur and Medipalli) conversion of scrubland followed by shallow water bodies, agriculture lands and deciduous forests into mining area was detected. However, the built-up land at all three-mining site was from cultivated lands and at Medipalli and Srirampur it was also contributed from scrubland. On the whole impact of open cast mining on deep water bodies was not detected. If the mining and surrounding regions continued and appropriate use of the land and water resources at hand, careful long-term planning is of utmost importance.