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Field courses can provide formative experiences that also reduce disparities in STEM education. Impacts of the ongoing COVID‐19 pandemic on‐field programs have been particularly severe, as many institutions shifted to online instruction. Some courses retained in‐person field experiences during the pandemic, and achieved high student learning outcomes. Here, I describe an approach to mitigating risk of COVID‐19 and other hazards during expedition‐based field courses, and student learning outcomes achieved using that approach. I applied comprehensive risk management to in‐person field expeditions that treated COVID‐19 as a hazard, requiring mitigation to maintain an acceptable low level of risk. Prior to broad availability of COVID‐19 vaccines, we applied a coronavirus‐free “bubble” strategy in which all participants passed a COVID‐19 PCR test immediately before departure and then avoided contact with people outside our bubble. In the future, vaccination can reduce risk further. We implemented additional safety factors to reduce risk of incidents that could require evacuation into medical facilities overloaded with COVID‐19 patients. The courses were successful: we had no infections or other serious incidents and student learning outcomes were transformative. The approach provides a model for conducting immersive field courses during the pandemic and beyond. Several field course networks are implementing similar approaches to restore valuable field education opportunities that have declined during the pandemic.

 

Abstract Human-driven threats are changing biodiversity, impacting ecosystem services. The loss of one species can trigger secondary extinctions of additional species, because species interact–yet the consequences of these secondary extinctions for services remain underexplored. Herein, we compare robustness of food webs and the ecosystem services (hereafter ‘services’) they provide; and investigate factors determining service responses to secondary extinctions. Simulating twelve extinction scenarios for estuarine food webs with seven services, we find that food web and service robustness are highly correlated, but that robustness varies across services depending on their trophic level and redundancy. Further, we find that species providing services do not play a critical role in stabilizing food webs – whereas species playing supporting roles in services through interactions are critical to the robustness of both food webs and services. Together, our results reveal indirect risks to services through secondary species losses and predictable differences in vulnerability across services. 

Predator–prey interactions shape ecosystems and can help maintain biodiversity. However, for many of the earth's most biodiverse and abundant organisms, including terrestrial arthropods, these interactions are difficult or impossible to observe directly with traditional approaches. Based on previous theory, it is likely that predator–prey interactions for these organisms are shaped by a combination of predator traits, including body size and species‐specific hunting strategies. In this study, we combined diet DNA metabarcoding data of 173 individual invertebrate predators from nine species (a total of 305 individual predator–prey interactions) with an extensive community body size data set of a well‐described invertebrate community to explore how predator traits and identity shape interactions. We found that (1) mean size of prey families in the field usually scaled with predator size, with species‐specific variation to a general size‐scaling relationship (exceptions likely indicating scavenging or feeding on smaller life stages). We also found that (2) although predator hunting traits, including web and venom use, are thought to shape predator–prey interaction outcomes, predator identity more strongly influenced our indirect measure of the relative size of predators and prey (predator:prey size ratios) than either of these hunting traits. Our findings indicate that predator body size and species identity are important in shaping trophic interactions in invertebrate food webs and could help predict how anthropogenic biodiversity change will influence terrestrial invertebrates, the earth's most diverse animal taxonomic group.