National Audubon Society

Abstract Natural history collections underpin our understanding of species distributions, yet some historical records remain embedded in modern avifaunal checklists despite limited documentation and no independent verification. One such case concerns the Dusky Parrot Pionus fuscus in Colombia: although reported from specimens collected by Melbourne A. Carriker Jr. in 1942 in the Serranía de Perijá, the species has not been observed in the country for nearly eight decades yet continues to be included in national checklists and conservation assessments. We reassessed the validity of this record by applying a multi-evidence framework integrating historic archival reconstruction, specimen-based morphological comparisons, climatic niche analyses, biogeographic limit assessment and contemporary survey-effort data. Historical documentation and morphological evidence based on high-resolution specimen images and associated curatorial records demonstrate that the Carriker specimens correspond to Pionus chalcopterus , not P. fuscus . Climatic niche analyses reveal minimal environmental overlap between P. chalcopterus and P. fuscus , and place the Perijá locality within the climatic niche of P. chalcopterus , while regional biogeography and extensive modern birdwatching coverage provide no support for the occurrence of P. fuscus in Perijá. Together, these concordant lines of evidence demonstrate that P. fuscus does not occur in Colombia. Our findings support its removal from national bird lists and conservation assessments and highlight how integrated, multi-evidence reassessments of historical records strengthen ornithological baselines, improve biogeographic inference and ensure that conservation priorities rest on verifiable evidence.

The lack of practical knowledge and effective engagement with gender in blue carbon initiatives poses a threat to their success and sustainability and risks exacerbating existing gender inequalities. Developed by an interdisciplinary team of experts, this paper proposes a research agenda, comprised of seven research areas as well as priority actions, designed to catalyze a shift towards more just, equitable and effective blue carbon initiatives. This paper is a call-to-action to increase commitment, funding, and collaborative, interdisciplinary science to close the gender gap in the conservation and restoration of blue carbon ecosystems and enhance their social-enovironmental impacts.

Automated radio telemetry systems (ARTS) consisting of animal-borne radio transmitters and networks of fixed radio receivers are frequently used to continuously track wildlife movements over time. The low weight of available radio transmitters and the ability of these systems to collect data with high temporal resolution make ARTS an attractive alternative to other wildlife tracking technologies. However, the research questions that can be addressed with ARTS are often limited by the spatial accuracy of location data produced by the system. One of the primary methods used to produce location estimates with ARTS involves comparing the received signal strength (RSS) of radio transmissions detected by multiple receivers in a network. The accuracy of the resulting locations is highly dependent on the algorithm used to process the raw RSS data generated by the ARTS into location estimates. In this work, we have developed a grid search algorithm for producing location estimates from RSS data generated by networks of receivers. In an experiment conducted with a radio transmitter and receiver network, we demonstrate that the grid search method produces location estimates that are greater than 2 times more accurate than the commonly used method of multilateration. A simulation was developed to compare the accuracy of the two methods over a large range of receiver spacings and with varying levels of measurement noise in the system. The simulation showed that the grid search method and multilateration perform similarly for receiver networks with relatively close receivers; however, as the distance between receivers in the array increases, the mean error of location estimates increases much more rapidly for multilateration than for grid search. The improvement in spatial accuracy realized through the use of grid search enables the design of wildlife tracking studies utilizing ARTS to address research questions that were previously inaccessible.

Monitoring contamination in soil and food systems remains vital for ensuring environmental and public health, particularly in agriculture-intensive regions. Existing laboratory-based techniques are often time-consuming, equipment-dependent, and impractical for rapid on-site screening. In this study, we present a portable, non-faradaic electrochemical impedance-based sensing platform capable of simultaneously detecting Salmonella Typhimurium (S. Typhi) and Aflatoxin B1 in spiked soil run-off samples. The system employs ZnO-coated electrodes functionalized with crosslinker for covalent antibody immobilization, facilitating selective, label-free detection using just 5 µL of sample. The platform achieves a detection limit of 1 CFU/mL for S. Typhi over a linear range of 10–105 CFU/mL and 0.001 ng/mL for Aflatoxin B1 across a dynamic range of 0.01–40.96 ng/mL. Impedance measurements captured with a handheld potentiostat were strongly correlated with benchtop results (R2 > 0.95), validating its reliability in field settings. The duplex sensor demonstrates high precision with recovery rates above 80% and coefficient of variation below 15% in spiked samples. Furthermore, machine learning classification of safe versus contaminated samples yielded an ROC-AUC > 0.8, enhancing its decision-making capability. This duplex sensing platform offers a robust, user-friendly solution for real-time environmental and food safety surveillance.

Abstract Salt marshes are dynamic biogeomorphic systems reliant on autochthonous and allochthonous input to maintain their three-dimensional configuration. Sea-level rise, subsidence, and sediment deficits can lead to submergence, open-water expansion, and ultimately loss of the vegetated marsh plain and associated ecosystem services. Widely used management-focused models focus on vegetation zonation in response to sea level but neglect sediment transport processes and geomorphic change. Process-based research models attempt to represent complex physical and biogeomorphic interactions but operate on spatiotemporal scales that are not directly transferable to restoration or management. Here we bridge these two paradigms and present a novel geomorphic model (UBMorph) based on the sediment-based lifespan concept that accounts for sea-level rise and open-water expansion to predict changes in salt marsh area in Chesapeake Bay. Model parameters such as surface accretion rate and elevation-to-areal loss fraction are selected using a separate, fully coupled biogeomorphic model (MarshMorpho2D) and the predicted lifespan is then compared with high marsh coverage from a zonation model (SLAMM). Across all of Chesapeake Bay, UBMorph estimates an overall loss of 404 km2 (37%) of vegetated marsh area under a dynamic 3–12 mm/y sea-level rise scenario (between 2010 and 2110). We then demonstrate a management-focused application of UBMorph and SLAMM used in tandem, for developing both a marsh condition and restoration model of the Chesapeake Bay portion of Maryland. The restoration model, which includes hydrologic intervention and sediment placement actions, indicates that ~ 400 km2 of marsh require either no intervention or low effort hydrologic intervention presently, whereas if no action is taken, over 700 km2 will require high effort intervention by 2070. This synthesis of research models with management-focused decision models demonstrates a tangible advance in bridging the gap between process-based research and restoration needs.

BackgroundMental health issues among Bangladeshi children and adolescents are increasing due to sociocultural factors. Despite its importance, in-depth research is scarce. This study addresses the gap by exploring mental health issues, risk factors and barriers to accessing care in rural and urban Bangladesh through qualitative methods.MethodsWe conducted semi-structured interviews with 38 participants across both rural and urban areas, including 12 in-depth interviews with children and adolescents, 10 key informant interviews with caregivers and 2 focus group discussions with community representatives, educators and healthcare providers. All interviews were transcribed verbatim and a thematic analysis was employed to identify key themes. In addition to the interviews, we utilized observational data and yearly records from ADD International Bangladesh, a community-based mental health organization, to provide contextual depth and triangulate findings.ResultsThe findings revealed three themes: mental health issues such as anxiety, depression, suicidal ideation and substance abuse; risk factors including device overuse, family conflicts and substance availability; and barriers to care such as lack of services, low mental health literacy and stigma from religious and societal beliefs.ConclusionsThe study provides an in-depth understanding of mental health issues, risk factors and barriers to care in rural and urban areas of Bangladesh. The findings enhance the understanding of the mental health status of young people and can inform policy development and the formation of suitable psychosocial interventions.

Recent studies have illustrated that high penetration of behind-the-meter (BTM) solar generation at transmission nodes has become a major issue for regional transmission organizations (RTOs). Therefore, it is of imperative needs for transmission system operators to accurately extract actual nodal demand and solar generation profiles. Motivated by these imminent real-world needs, this paper proposes a holistic three-layer framework to integrate novel techniques such as Ordinal Partition Graph (OPG)-based time-series embedding, Topological Data Analysis (TDA)-based feature extraction, and a deep-learning-based classification module. Firstly, real-world aggregated, nodal data is represented by various high-dimensional topology via novel embedding technique. Secondly, persistence images (PI), which contains selected topological features, are computed by filtration. Finally, a deep-learning module is designed for unsupervised classification. The proposed framework is numerically validated using real nodal load data from PJM Interconnection, a major RTO within the U.S.

Lateral lumbar interbody fusion (LLIF) is a minimally invasive surgical technique that provides a wide footprint interbody cage for correction of lumbar coronal and sagittal deformity. Traditional spinal interbody fusion procedures utilize pedicle screws and rods for additional stability. An expandable lateral titanium interbody cage with an integrated lateral fixation (eLLIFp) device provides a stand-alone LLIF that is intended to function autonomously. This may reduce the complexity of the surgery and the potential risks associated with supplemental posterior instrumentation. The minimum-acceptable screw length to promote adequate biomechanical fixation and stability for a stand-alone eLLIFp has not been determined. To investigate the effective ratio (of screw length/cage length) of a stand-alone eLLIFp construct that provides adequate biomechanical fixation and stability as compared to the eLLIFp with supplemental bilateral pedicle screw-rod fixation. In vitro cadaveric biomechanical testing and finite element modeling. Eight fresh-frozen human cadaveric lumbar spine specimens (L2-5) were used. Range-of-motion (ROM) measurements of intact and treated specimens with simulated stresses within the construct and surrounding bone during flexion-extension (FE), lateral bending (LB), and axial rotation (AR). Specimens with similar age and DEXA scores were selected. ROM of intact specimens was measured before treatment with LLIF at L3-4. Specimens were treated with expandable lateral cages with integrated fixation (stand-alone eLLIFp) or eLLIFp with supplemental posterior fixation using bilateral pedicle screws and rods (eLLIFp + BPS). ROM was measured using a custom-built 6°-of-freedom motion simulator (±7.5Nm) and normalized as a percentage of intact. Four patient-specific lumbar functional spinal unit finite element models (FEMs) were developed, validated, and then instrumented with eLLIFp stand-alone devices. The integrated screw lengths were varied to achieve screw-to-cage length ratios of 0.6, 0.75 and 0.9. Stresses were compared among the constructs under a 7.5Nm pure moment load in FE, LB, and AR. The stand-alone and posteriorly supplemented eLLIFp constructs were not sensitive to the ratio during FE and LB (with only a 4%-9% change in motion trends from low-to-high ratios, relative to intact). Independent of ratio, these constructs had minimal differences in FE and LB motion. However, during AR both constructs were sensitive to the ratio showing greater stability and less variability in performance with higher ratios (≥0.65). Regression analysis revealed that posteriorly supplemented eLLIFp constructs had a linear 13% reduction in AR motion as the ratio increased from low-to-high (p<.05). AR also imposed the highest stresses on the eLLIFp and these stresses increased with higher ratios (maximum stress 259MPa for ratio 0.9 during AR), yet implant failure was improbable because of the material properties of the titanium alloy used. Similarly, surrounding bone stresses were higher during AR and longer screws reduced these stresses (63MPa with a 0.6 ratio compared to 38MPa with a 0.9 ratio). Independent of screw-to-cage length ratio, eLLIFp had comparable reduction of FE and LB motion with or without posterior fixation. For eLLIFp with and without posterior fixation, torsional performance and repeatability increased with screw-to-cage length ratio. Torsional stability was comparable between stand-alone eLLIFp with high ratios (≥0.65) and posteriorly supplemented eLLIFp with low ratios (0.55). However, a threshold screw-to-cage length ratio for optimizing the clinical performance of eLLIFp cannot be prescribed. Implant stress findings reinforced torsion as the critical loading condition. Surrounding bone stress decreased as the screw length increased, indicating the benefit of using longer screws. Surgeons using eLLIFp should consider longer screw lengths based on anatomical considerations. eLLIFp cages can be used as a stand-alone device in appropriately selected patients. This avoids the morbidity and cost associated with futher supplemental posterior fixation. Surgeons using eLLIFp should consider using longer screws to optimize fixation.

The central northern coast of South America has extensive wetlands critical for waterbird conservation. While waterbird harvest occurs in the region, the impact on species population dynamics remains unclear. This study assesses waterbird hunting in the coastal wetlands of Suriname, addressing: (i) the extent of waterbird harvest, (ii) changes in harvest magnitude over time, and (iii) the motivations and methods of hunters. We collected data via a national survey of licensed hunters in 2006 and 2016 using structured interviews. A Bayesian hierarchical model was used to analyze the data. We estimated harvest levels for 11 species and three groups (small herons, small shorebirds, large shorebirds). For most species, mean harvest per hunter significantly decreased from 2006 to 2016, except for blue-winged teal and migratory shorebirds. Most hunting was for non-commercial purposes (personal consumption and recreational). This is the first national assessment of waterbird hunting in Suriname. Harvest levels vary by species, and the sustainability of these levels remains uncertain. Managing hunting in Suriname requires addressing both legal and illegal hunting. Given Suriname importance for waterbirds, particularly species like the scarlet ibis and migratory shorebirds, it should be a priority for conservation efforts.