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1. Assessing the role of habitat and species interactions in the population decline and detection bias of Neotropical leaf litter frogs in and around La Selva Biological Station, Costa Rica

   https://doi.org/10.3897/neotropical.14.e37526  

   Vera Alvarez, Maria D.; Fernandez, Christopher; Cove, Michael V. (July 2019, Neotropical Biology and Conservation)

   null (Ed.)

   Worldwide, amphibian populations have been declining rapidly. This decline can be attributed to many factors including climate change, pesticide exposure, and emerging infectious diseases, among other important factors, but few studies have examined the influence of species interactions. In this study, we examined how habitat factors and co-occurring avian and mammalian species, as well as humans, exert direct and indirect effects on Neotropical amphibian population dynamics. We further examined how these habitat and species interactions could affect our ability to reliably detect amphibian presence to robustly estimate population trends. We conducted amphibian visual encounter surveys at 26 randomly selected sites in the La Selva Biological Station, in northeastern Costa Rica, as well as 26 sites across five additional forest fragments in the region. Furthermore, we used camera traps to collect data on avian and mammalian communities and human visitation at those amphibian survey plots. From these data, we were able to estimate species occupancy probabilities for leaf litter frogs across sites and their relationships to habitat and interspecific species interaction covariates. We also conducted an experiment with plastic model frogs to estimate detection probabilities when a population is known to occur at a site with certainty. Our results suggested that strawberry poison dart frog ( Oophagapumilio ) occupancy was positively related to secondary forest and their detection was negatively related to increasing air temperatures at the times of the surveys. Leaf litter frog occupancy was negatively related to core La Selva sites and human detections at sites, yet their detection was positively related to human trail presence, which might be related to reduced leaf litter cover due to heavy trampling. Our experimental surveys suggested that Neotropical leaf litter frog communities are difficult to detect when present and future studies should explicitly account for this detection bias to effectively monitor population trends. 

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2. Indy Survey Tool: A Framework to Unearth Correlations in Survey Data

   https://doi.org/10.1109/VIS54172.2023.00038  

   Crnovrsanin, Tarik; Di_Bartolomeo, Sara; Wilson, Connor; Dunne, Cody (October 2023, IEEE)

   Survey companion websites allow users to explore collected survey information more deeply, as well as update or add entries for papers. These sites can help information stay relevant past the original release date of the survey paper. However, creating and maintaining a website can be laborious and difficult, especially when authors might not be experienced with programming. We introduce Indy Survey Tool to help authors develop companion websites for survey papers across diverse fields of study. The tool's core aim is to identify correlations between categorizations of papers. To accomplish this, the tool offers multiple combined filters and correlation matrix visualizations that enable users to explore the data from diverse perspectives. The tool's visualizations, list of papers, and filters are harmoniously integrated and highly responsive, providing users with feedback based on their selections. Identifying correlations in survey papers is a pivotal aspect of research, as it can enable the recognition of common combinations of categorizations within the papers—as well as highlight any omissions. The versatility of Indy Survey Tool enables researchers to delve into the correlations between categorizations in survey data, an essential aspect of research that can reveal gaps in the literature and highlight promising areas for future exploration. A preprint and supplemental material for the paper can be found at osf.io/tdhqn. 

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3. Navajo Nation snowpack variability from 1985-2014 and implications for water resources management

   Tsinnajinnie, L.; Gutzler, D.S.; John, J. (April 2018, Journal of contemporary water research and education)

   Abstract: In the arid Southwest, snowpack in mountains plays an essential role in supplying surface waterresources. Water managers from the Navajo Nation monitor snowpack at nine snow survey stations located in the Chuska Mountains and Defiance Plateau in northern Arizona and New Mexico. We characterize these snowpack data for the period 1985-2014 and evaluate the efficacy of snowpack data collection efforts. Peak snow water equivalent occurs in early to mid-March depending on elevation. Variability in snowpack levels correlates highly among all sites (r > 0.64), but higher elevation sites in the Chuska Mountains correlate more strongly with one another compared to lower elevation sites and vice versa. Northern sites also correlate well with each other. A principal component analysis is used to create a weighted average time series of year-to-year peak snowpack variability. The first principal component showed no trend in increasing or decreasing Navajo Nation snowpack. Results from this research will provide the Navajo Nation Department of Water Resources information to help determine if any snow survey sites in the Chuska Mountains are redundant and can be discontinued to save time and money, while still providing snowpack information needed by the Navajo Nation. This summary of snowpack patterns, variability, and trends in the Chuska Mountains and Defiance Plateau will help the Navajo Nation to understand how snowpack and water resources respond to climate change and climate variability. 

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4. Discovery of Two Polars from a Crossmatch of ZTF and the SRG/eFEDS X-Ray Catalog

   https://doi.org/10.3847/1538-4357/acbb6f  

   Rodriguez, Antonio C.; Kulkarni, Shrinivas R.; Prince, Thomas A.; Szkody, Paula; Burdge, Kevin B.; Caiazzo, Ilaria; van Roestel, Jan; Vanderbosch, Zachary P.; El-Badry, Kareem; Bellm, Eric C.; et al (March 2023, The Astrophysical Journal)

   Abstract Magnetic cataclysmic variables (CVs) are luminous Galactic X-ray sources, which have been difficult to find in purely optical surveys due to their lack of outburst behavior. The eROSITA telescope on board the Spektr-RG mission is conducting an all-sky X-ray survey and recently released the public eROSITA Final Equatorial Depth Survey (eFEDS) catalog. We crossmatched the eFEDS catalog with photometry from the Zwicky Transient Facility and discovered two new magnetic CVs. We obtained high-cadence optical photometry and phase-resolved spectroscopy for each magnetic CV candidate and found them both to be polars. Among the newly discovered magnetic CVs is eFEDS J085037.2+044359/ZTFJ0850+0443, an eclipsing polar with orbital period P orb = 1.72 hr and WD mass M WD = 0.81 ± 0.08 M ⊙ . We suggest that eFEDS J085037.2+044359/ZTFJ0850+0443 is a low magnetic field strength polar, with B WD ≲ 10 MG. We also discovered a non-eclipsing polar, eFEDS J092614.1+010558/ZTFJ0926+0105, with orbital period P orb = 1.47 hr and magnetic field strength B WD = 36–42 MG. 

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5. An empirical evaluation of camera trap study design: How many, how long and when?

   https://doi.org/10.1111/2041-210X.13370  

   Kays, Roland; Arbogast, Brian S.; Baker‐Whatton, Megan; Beirne, Chris; Boone, Hailey M.; Bowler, Mark; Burneo, Santiago F.; Cove, Michael V.; Ding, Ping; Espinosa, Santiago; et al (April 2020, Methods in Ecology and Evolution)

   Abstract Camera traps deployed in grids or stratified random designs are a well‐established survey tool for wildlife but there has been little evaluation of study design parameters.We used an empirical subsampling approach involving 2,225 camera deployments run at 41 study areas around the world to evaluate three aspects of camera trap study design (number of sites, duration and season of sampling) and their influence on the estimation of three ecological metrics (species richness, occupancy and detection rate) for mammals.We found that 25–35 camera sites were needed for precise estimates of species richness, depending on scale of the study. The precision of species‐level estimates of occupancy (ψ) was highly sensitive to occupancy level, with <20 camera sites needed for precise estimates of common (ψ > 0.75) species, but more than 150 camera sites likely needed for rare (ψ < 0.25) species. Species detection rates were more difficult to estimate precisely at the grid level due to spatial heterogeneity, presumably driven by unaccounted habitat variability factors within the study area. Running a camera at a site for 2 weeks was most efficient for detecting new species, but 3–4 weeks were needed for precise estimates of local detection rate, with no gains in precision observed after 1 month. Metrics for all mammal communities were sensitive to seasonality, with 37%–50% of the species at the sites we examined fluctuating significantly in their occupancy or detection rates over the year. This effect was more pronounced in temperate sites, where seasonally sensitive species varied in relative abundance by an average factor of 4–5, and some species were completely absent in one season due to hibernation or migration.We recommend the following guidelines to efficiently obtain precise estimates of species richness, occupancy and detection rates with camera trap arrays: run each camera for 3–5 weeks across 40–60 sites per array. We recommend comparisons of detection rates be model based and include local covariates to help account for small‐scale variation. Furthermore, comparisons across study areas or times must account for seasonality, which could have strong impacts on mammal communities in both tropical and temperate sites. 

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