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Concentrations of pollutants in Saskatchewan forest soils are low but are highly variable.Distinct spatial patterns in surface soil pollutant concentration are evident.Patterns in soil Hg and V and SO42−are strongly related to soil organic matter.Concentrations of Cu, Ni and Zn influenced by soil factors in addition to organic matter.Atmospheric deposition plays a minor role in pollutant levels in northern Saskatchewansoils. Long‐range transport and subsequent atmospheric deposition of pollutants has led to soil contamination around the globe. Northern Saskatchewan is downwind of major emissions of sulfur (S), nitrogen (N), and heavy metals vanadium (V) and nickel (Ni) associated with oil sands activities, leading to concerns over possible soil contamination. In this study we sampled 200 forested sites spanning five ecoregions of Saskatchewan. Surface (A‐horizon) soils were measured for a suite of traditional chemical indicators of atmospheric pollution (e.g., SO42–, NO3−, Hg, heavy metals). In general, metal concentrations in surface soils were among the lowest reported in the literature indicating low levels of soil contamination. Despite the remote location of the sites there was a large range in pollution soil indicators in surface soil. For example, Hg concentrations were between 0.6 and 53.3 μg g−1, V concentrations varied from <0.02 to 161 mg kg−1, and extractable SO42–was between 0.2 and 52.2 mg kg−1and distinct spatial patterns were evident. Higher concentrations of pollutants were observed in southern, eastern and northern parts of the study area. Much of the variability in surface soil chemistry was explained by soil factors and in particular organic matter as the dominant controls of these pollution indicators. Lower values of these indicators were found in sandy soils low in organic matter such as those occurring in the Athabasca Plain located south of Lake Athabasca closest to oil sands activities.

RNA viruses are unique in their evolutionary capacity, exhibiting high mutation rates and frequent recombination. They rapidly adapt to environmental changes, such as shifts in immune pressure or pharmacological challenge. The evolution of RNA viruses has been brought into new focus with the recent developments of genetic and experimental tools to explore and manipulate the evolutionary dynamics of viral populations. These studies have uncovered new mechanisms that enable viruses to overcome evolutionary challenges in the environment and have emphasized the intimate relationship of viral populations with evolution. Here, we review some of the emerging viral and host mechanisms that underlie the evolution of RNA viruses. We also discuss new studies that demonstrate that the relationship between evolutionary dynamics and virus biology spans many spatial and temporal scales, affecting transmission dynamics within and between hosts as well as pathogenesis.

Engagement of undergraduate students in research has been demonstrated to correlate with improved academic performance and retention. Research experience confers many benefits on participants, particularly foundational skills necessary for graduate school and careers in scientific disciplines. Undergraduate curricula often do not adequately develop collaborative skills that are becoming increasingly useful in many workplaces and research settings. Here, we describe a pilot program that engages undergraduates in research and incorporates learning objectives designed to develop and enhance collaborative techniques and skills in team science that are not typical outcomes of the undergraduate research experience. We conducted a collaborative science project that engaged faculty advisors and upper year undergraduates at four institutions and conducted a review to assess the program’s efficacy. Students developed a broad suite of competencies related to collaborative science, above and beyond the experience of completing individual projects. This model also affords distinct advantages to faculty advisors, including the capacity of the network to collect and synthesize data from different regions. The model for training students to conduct collaborative science at an early stage of their career is scalable and adaptable to a wide range of fields. We provide recommendations for refining and implementing this model in other contexts.

The article discusses the significance and revival of the Eucharist by the new converts to Catholicism. Topics include the power of the faith of cradle Catholics who admire the Eucharist, Eucharistic revival by the U.S. bishops, the understanding of many new Catholics of the Eucharist as less cultural and more biblical.

Brood parasitism by the brown‐headed cowbird (Molothrus ater) has caused population declines for conservation‐reliant songbird species such as the federally and state endangered subspecies least Bell's vireo (Vireo bellii pusillus). Although cowbird trapping has increased vireo populations, it is costly, and may prevent the development of parasitism‐avoidance behaviors and result in high rates of non‐target species captures. Therefore, wildlife managers have a compelling interest in evaluating multiple means of cowbird control. We conducted a study between 2016 and 2018 on the Santa Clara River (SCR) in Ventura County, California, USA, to test how the removal of cowbird traps would affect cowbird parasitism of the vireo. At our control site, cowbird trapping occurred in spring using modified Australian crow (Corvusspp.) traps. At our treatment site, we stopped this method of trapping and instead used target‐netting of individual cowbirds and a very short duration trap to capture specific individual cowbirds (i.e., contingency trapping). We also tested the impact of shortening the cowbird trapping period on nest parasitism rates, and used point counts to compare cowbird densities between sites. Additionally, we compared the costs of these techniques. A shorter trapping period still resulted in a large number of cowbird captures on the control site (n= 452 captures) with no observed brood parasitism (n= 67 nests). On the treatment site, cowbird parasitism rates varied from 0% to 14% (n= 75 broods). The target‐netting method was not effective for capturing female cowbirds, probably because of their low densities. The short‐term contingency trapping method effectively removed female cowbirds in the vicinity of vulnerable vireo nests. Cowbird traps captured >300 individuals of 9 different non‐target species each year on the control site, whereas target‐netting and contingency trapping resulted in only 8 captures of 4 different non‐target species. Costs of continuous trapping for 2 months versus point counts, nest monitoring, and contingency trapping were $21,100.00 versus $16,996.00, respectively. Based on these findings, we recommend that an adaptive cowbird management program to benefit songbird populations should consider using regular point counts and nest monitoring to provide data on cowbird impacts, in lieu of continued intensive trapping without monitoring. Thresholds for the density of cowbird females and the allowable level of parasitism for host species should also be established to guide an adaptive cowbird management program. Short‐term contingency trapping based on the thresholds should be considered, but restoration of native vegetation, especially in southwestern riparian areas, is also crucial and effective at limiting parasitism, and so should strongly be considered. Lastly, large numbers of non‐target species captures in cowbird traps are probably having consequential impacts to these species, and need to be monitored and minimized. At the Santa Clara River in Ventura County, California, shortening the trapping season by a month can eliminate brood parasitism of songbird nests and is less costly. Very short duration trapping worked well to capture individual cowbirds, but mist‐netting did not. Cowbird trapping should be used in a sparing and targeted fashion to avoid harming other species, and to make the best use of conservation funds.