Propelled Abrasive Grit Applications for Weed Management in Transitional Corn Grain Production

Weed control is challenging to farmers who are transitioning from production systems that use synthetic herbicides to organic systems. A 2-year field study examined air-propelled corncob grit abrasion for in-row weed control efficacy and effect on corn yield. Grit was applied based on corn vegetative developmental stages with one (V1, V3 or V5), two (V1 + V3, V1 + V5, or V3 + V5), or three (V1 + V3 + V5) applications. Flame-weeding or cultivation was used after the V5 application for between-row weed control. Grit applications decreased in-row weed densities by about 60% (α = 0.05) and biomass up to 95% (α = 0.001). Between-row treatments provided similar control, and reduced weed biomass by 55% in 2013 (α = 0.01) and 86% (α = 0.001) in 2014. In-row grit treatments increased corn yield up to 44%, and yield was more influenced by in-row weeds than between row weeds. These results indicate that abrasive corncob grit for in-row weed control, supplemented with cultivation or flaming, can reduce weed biomass substantially and help maintain corn yield. However, timing and frequency of grit application need further refinement based on weed growth as influenced by climate, as treatments at similar corn growth stages did not consistently provide adequate weed control between years

Black Vulture Conflict and Management in the United States: Damage Trends, Management Overview, and Research Needs

Contrary to rapid declines of many vulture (Accipitridae, Cathartidea) species worldwide, black vulture (Coragyps atratus) populations are increasing and expanding their range in North America. Vultures exhibit complex behaviors and can adapt to any human-dominated landscape or land use. These traits, combined with population growth and range expansion, have contributed to increased human–vulture conflicts. Our goal was to summarize the current status and trends in human–black vulture conflicts (hereafter human–vulture conflicts), review available management strategies, identify knowledge gaps, and provide recommendations to enhance management and understanding of this species and the associated conflicts. We found human–vulture conflicts are increasing in agriculture (livestock), private and public property (both personal and infrastructure-based), and threats to human health and safety. The greatest increases in conflicts were reported in agriculture and private and public property damage. Regarding livestock depredation, good progress has been made toward assessing producer perceptions of the conflicts, including estimates of economic damage and mitigation strategies, but a basic understanding of the underlying mechanism driving the conflict and advancing strategies to mitigate damage is lacking. For damaged property, little information is available regarding economic losses and perceptions of stakeholders who are experiencing the damage, and most of the tools recommended for mitigating this damage have not been rigorously evaluated. Regarding human health and safety, recent research quantifying flight behavior of black vultures has direct implications for reducing aircraft collision risks. However, it is unclear what factors influence roost site selection and the most effective means to leverage the sensory ecology of the species to mitigate risks. We identify additional knowledge gaps and research needs that if addressed could increase managers’ understanding of black vulture ecology and facilitate enhanced management of this species while simultaneously allowing for the species to provide valuable ecosystem services

Cultivation of Industrial Hemp on and Near Airports: Implications for Wildlife Use and Risk to Aviation Safety

Land-use planning on and near airports should consider possible revenue from land covers, associated maintenance costs, and potential for land covers to attract vertebrate species recognized as hazardous to aviation safety. The U.S. Federal Aviation Administration has expressed interest in recent attention given to industrial hemp (Cannabis sativa L.; hemp) as a revenue-producing land cover that might be cultivated on or near airports. Our purpose was to better understand the potential production value of hemp as well as its possible role in affecting aviation safety if cultivated on or near airports. Our objectives were to: (1) review the literature relative to a historical perspective of hemp cultivation in the United States, projected cultivation practices, and anticipated economic viability, (2) use our review to gather information on vertebrate use of hemp cultivars, and (3) revisit U.S. and international regulations on land covers near airports relative to attraction of species recognized as hazardous to aviation safety. We found, via review of peer-reviewed and gray literature, that hemp holds potential as an emerging crop in the United States, contributing to food, medicine, and biomass-derived products as well as evidence that birds will use, if not depredate, the crop. However, future markets promoting cultivation of hemp remain tentative. Further, there has been no objective quantification of bird and other wildlife use of hemp alone or as a component of a land cover matrix on or near airports and relative to implications for aviation safety. We make recommendations for future research on wildlife use of hemp and metrics necessary to inform aviation safety

Industrial Hemp as a Resource for Birds in Agroecosystems: Human–Wildlife Conflict or Conservation Opportunity?

Industrial hemp (Cannabis sativa L.; hemp) is an emerging crop in the United States with little known about bird use or the potential for birds to become an agricultural pest. We identified birds associated with hemp fields, using repeated visits to oilseed plots in North Dakota, USA (n = 6) and cannabinoid (CBD) plots in Florida, USA (n = 4) from August to November 2020. We did not control for plot area or density; our observations were descriptive only. We observed 10 species in hemp, 12 species flying over hemp, and 11 species both foraging in and flying over hemp fields in North Dakota. In Florida, we observed 4 species in hemp, 5 species flying over hemp, and 4 species exhibiting both behaviors. When we observed birds in hemp, we found them perched in the canopy or foraging on the ground. Counts were highest in oilseed and lowest in CBD varieties. The Florida sites were mainly CBD varieties, which explains lower species diversity and raw counts of birds given the lack of seeds produced. Maximum raw counts of the most common birds (mourning doves [Zenaida macroura] = 116; house finches [Haemorhous mexicanus] = 53; and American goldfinches [Spinus tristis] = 40) using very small fields (116–324 m2) in North Dakota suggest oilseed hemp could suffer yield losses but potentially benefit farmland bird conservation and act as a decoy crop to protect other commodities (e.g., sunflower [Helianthus annuus L.])

Spatial risk modeling of cattle depredation by black vultures in the midwestern United States

ock operations through depredation of stock are a cause of human‐wildlife conflict. Management of such conflict requires identifying environmental and non‐environmental factors specific to a wildlife species\u27 biology and ecology that influence the potential for livestock depredation to occur. Identification of such factors can improve understanding of the conditions placing livestock at risk. Black vultures (Coragyps atratus) have expanded their historical range northward into the midwestern United States. Concomitantly, an increase in concern among agricultural producers regarding potential black vulture attacks on livestock has occurred. We estimated area with greater or lesser potential for depredation of domestic cattle by black vultures across a 6‐state region in the midwestern United States using an ensemble of small models (ESM). Specifically, we identified landscape‐scale spatial factors, at a zip code resolution, associated with reported black vulture depredation on cattle in midwestern landscapes to predict future potential livestock depredation. We hypothesized that livestock depredation would be greatest in areas with intensive beef cattle production close to preferred black vulture habitat (e.g., areas with fewer old fields and early successional vegetation paired with more direct edge between older forest and agricultural lands). We predicted that the density of cattle within the county, habitat structure, and proximity to anthropogenic landscape features would be the strongest predictors of black vulture livestock‐depredation risk. Our ESM estimated the relative risk of black vulture‐cattle depredation to be between 0.154–0.631 across our entire study area. Consistent with our hypothesis, areas of greatest predicted risk of depredation correspond with locations that are favorable to vulture life‐history requirements and increased potential to encounter livestock. Our results allow wildlife managers the ability to predict where black vulture depredation of cattle is more likely to occur in the future. It is in these areas where extension and outreach efforts aimed at mitigating this conflict should be focused. Researchers and wildlife managers interested in developing or employing tools aimed at mitigating livestock‐vulture conflicts can also leverage our results to select areas where depredation is most likely to occur

Modeling Wildlife Damage to Crops in Northern Indiana

Comprehensive information on crop damage by wildlife species is critical if effective strategies for controlling wildlife damage are to be formulated. Discriminating how landscape composition and configuration attributes influence crop damage is important for implementing landscape management techniques to resolve human–wildlife conflicts. We analyzed crop damage data from 100 corn fields and 60 soybean fields located in the Upper Wabash River Basin of northern Indiana during 2003 and 2004. We used negative binomial regression to model the rate of damage to corn and soybean crops in response to local and landscape variables. Rate of crop damage was best predicted by a combination of local and landscape variables for both corn and soybeans. Models with landscape configuration variables were better able to explain patterns of corn damage, and models with landscape composition variables (specifically, amount of wooded areas) were better able to explain patterns of soybean damage. In general, rate of crop damage was negatively related to size of the crop field and positively related to proportion of a field’s perimeter that was adjacent to wooded areas, amount of wooded areas, amount of forest edge, and mean size of forest patches. Specific associations between local and landscape variables and rates of crop damage may serve as a guide to planting strategies and landscape management to minimize wildlife damage to crops

Clinical laboratory reference values amongst children aged 4 weeks to 17 months in Kilifi, Kenya: A cross sectional observational study

Reference intervals for clinical laboratory parameters are important for assessing eligibility, toxicity grading and management of adverse events in clinical trials. Nonetheless, haematological and biochemical parameters used for clinical trials in sub-Saharan Africa are typically derived from industrialized countries, or from WHO references that are not region-specific. We set out to establish community reference values for haematological and biochemical parameters amongst children aged 4 weeks to 17 months in Kilifi, Kenya. We conducted a cross sectional study nested within phase II and III trials of RTS, S malaria vaccine candidate. We analysed 10 haematological and 2 biochemical parameters from 1,070 and 423 community children without illness prior to experimental vaccine administration. Statistical analysis followed Clinical and Laboratory Standards Institute EP28-A3c guidelines. 95% reference ranges and their respective 90% confidence intervals were determined using non-parametric methods. Findings were compared with published ranges from Tanzania, Europe and The United States. We determined the reference ranges within the following age partitions: 4 weeks to <6 months, 6 months to less than <12 months, and 12 months to 17 months for the haematological parameters; and 4 weeks to 17 months for the biochemical parameters. There were no gender differences for all haematological and biochemical parameters in all age groups. Hb, MCV and platelets 95% reference ranges in infants largely overlapped with those from United States or Europe, except for the lower limit for Hb, Hct and platelets (lower); and upper limit for platelets (higher) and haematocrit(lower). Community norms for common haematological and biochemical parameters differ from developed countries. This reaffirms the need in clinical trials for locally derived reference values to detect deviation from what is usual in typical children in low and middle income countries

Psychological well-being in Europe after the outbreak of war in Ukraine

The Russian invasion of Ukraine on February 24, 2022, has had devastating effects on the Ukrainian population and the global economy, environment, and political order. However, little is known about the psychological states surrounding the outbreak of war, particularly the mental well-being of individuals outside Ukraine. Here, we present a longitudinal experience-sampling study of a convenience sample from 17 European countries (total participants = 1,341, total assessments = 44,894, countries with >100 participants = 5) that allows us to track well-being levels across countries during the weeks surrounding the outbreak of war. Our data show a significant decline in well-being on the day of the Russian invasion. Recovery over the following weeks was associated with an individual’s personality but was not statistically significantly associated with their age, gender, subjective social status, and political orientation. In general, well-being was lower on days when the war was more salient on social media. Our results demonstrate the need to consider the psychological implications of the Russo-Ukrainian war next to its humanitarian, economic, and ecological consequences