Scholarship & Research
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Item Bees and Butterflies in Roadside Habitats: Identifying Patterns, Protecting Monarchs, and Informing Management(ITD Reseach Program, 2023-07) Meinzen, Thomas C.; Debinski, Diane M.; Burkle, Laura A.; Ament, Robert J.Pollinating insects provide vital ecosystem services and are facing global declines and habitat loss . Roadsides are increasingly regarded as important potential areas f or enhancing pollinator habitat. Understanding which roadsides best support pollinators — and why — is essential to helping locate and prioritize pollinator conservation efforts across roadside networks. To support this effort, we assessed butterfly, bee, and flowering plant species richness and abundance on a set of 63 stratified randomized roadside transects in State-managed rights-of-way in SE Idaho. Our research evaluated pollinator diversity as a function of highway class (interstate, U.S., and state highways), remotely sensed NDVI values (a measure of vegetation greenness), and floral resources. We found that smaller highways and lower (less green) maximum NDVI values were associated with significantly more bee species and total bees. Roadsides bordering sagebrush habitats typically had low NDVI values and higher bee and butterfly species richness, potentially contributing to this observed pattern. Butterfly richness increased in association with higher floral abundance in roadsides. Additionally, we identified and mapped 1,363 roadside patches of milkweed (Asclepias speciosa), larval host plant for the imperiled monarch butterfly (Danaus plexippus), in a survey of over 900 miles of southern Idaho highways. Based on these results and a literature review, we recommend management strategies to promote the health of pollinator populations in Idaho’s rights-of-way and provide data to help ITD prioritize areas for pollinator-friendly management practices and habitat restoration within their highway system.Item Increasing equitable access to graduate education through competitive hiring in the life sciences(Wiley, 2023-06) Carroll, Kathleen A.; Lance, Michael J.; Smithers, Brian V.; Debinski, Diane M.Many professions necessitate a graduate-level education, and research conducted by graduate students is integral in many fields, particularly those in the life science programs like ecology and environmental sciences. However, practices for recruiting and selecting graduate students are inconsistent among and within institutions. Although some institutions, departments, or faculty members hire graduate students through open and competitive graduate student hiring processes, graduates are frequently selected through inconsistent processes that limit the pool of applicants and do not maximize the potential for increasing workforce diversity. Here, we review and evaluate six approaches to graduate recruitment processes common in ecology and environmental science degree programs in the US to determine which approaches, or combinations of approaches, could increase equity in career development opportunities, promote workforce diversity, and provide clear justifications to funding bodies. We compiled our list of recruitment methods through informal interviews with recruiters, administrators, faculty, and graduate students in ecology, natural resources, and environmental sciences. We determined that three of the six approaches examined were most effective in supporting equitable graduate student hiring practices, and three were not. While life science fields were the primary focus of this review, our approach to evaluating graduate recruitment methods is widely applicable across disciplines where graduate students conduct research.Item Warming temperatures affect meadow‐wide nectar resources, with implications for plant–pollinator communities(Wiley, 2022-07) McCombs, Audrey L.; Debinski, Diane M.; Reinhardt, Keith; Germino, Matthew J.; Caragea, PetrutzaNectar production may be a point of sensitivity that can help link primary and secondary trophic responses to climate shifts, and is therefore important to our understanding of ecosystem responses. We evaluated the nectar response of two widespread native forbs, Balsamorhiza sagittata and Eriogonum umbellatum, to experimental warming in a high-elevation sagebrush meadow in the Teton Range, WY, USA, over two years, 2015 and 2016. Warming treatments reduced the occurrence of nighttime freezing and nectar volume but increased sugar concentration in nectar in both species in both years. Warming effects were also evident in a consistent increase in the number of flowers produced by B. sagittata. Our research suggests that warming associated with climate change has the potential to induce shifts in the nectar-feeding community by changing nectar characteristics such as volume and sugar concentration to which nectar feeders are adapted.Item Earlier spring snowmelt drives arrowleaf balsamroot phenology in montane meadow(Wiley, 2022-08) Durney, J. Simone; Engel, Arden; Debinski, Diane M.; Burkle, Laura A.Climate change is shifting phenology globally, altering when and how species respond to environmental cues such as temperature and the timing of snowmelt. These shifts may result in phenological mismatches among interacting species, creating cascading effects on community and ecosystem dynamics. Using passive warming structures and snow removal, we examined how experimentally increased temperatures, earlier spring snowmelt, and the poorly understood interaction between warming and earlier spring snowmelt affected flower onset, flowering duration, and maximum floral display of the spring-flowering montane species, arrowleaf balsamroot (Balsamorhiza sagittata), over a 7-year period. Additionally, potential cumulative effects of treatments were evaluated over the study duration. The combination of heating with snow removal led to earlier flower onset, extended flowering duration, and increased maximum floral display. While there was year-to-year variation in floral phenology, the effect of heating with snow removal on earlier onset and maximum floral display strengthened over time. This suggests that short-term studies likely underestimate the potential for climate change to influence phenological plant traits. Overall, this research indicates that B. sagittata's flowering onset responded more strongly to snow removal than to heating, but the combination of heating with snow removal allowed plants to bloom earlier, longer, and more profusely, providing more pollinator resources in spring. If warming and early snowmelt cause similar responses in other plant species, these patterns could mitigate phenological mismatches with pollinators by providing a wider window of time for interaction and resiliency in the face of change. This example demonstrates that a detailed understanding of how spring-flowering plants respond to specific aspects of predicted climatic scenarios will improve our understanding of the effects of climate change on native plant–pollinator interactions in montane ecosystems. Studies like this help elucidate the long-term physiological effects of climate-induced stressors on plant phenology in long-lived forbs.Item Warming temperatures affect meadow‐wide nectar resources, with implications for plant–pollinator communities(Wiley, 2022-07) McCombs, Audrey L.; Debinski, Diane M.; Reinhardt, Keith; Germino, Matthew J.; Caragea, PetrutzaNectar production may be a point of sensitivity that can help link primary and secondary trophic responses to climate shifts, and is therefore important to our understanding of ecosystem responses. We evaluated the nectar response of two widespread native forbs, Balsamorhiza sagittata and Eriogonum umbellatum, to experimental warming in a high-elevation sagebrush meadow in the Teton Range, WY, USA, over two years, 2015 and 2016. Warming treatments reduced the occurrence of nighttime freezing and nectar volume but increased sugar concentration in nectar in both species in both years. Warming effects were also evident in a consistent increase in the number of flowers produced by B. sagittata. Our research suggests that warming associated with climate change has the potential to induce shifts in the nectar-feeding community by changing nectar characteristics such as volume and sugar concentration to which nectar feeders are adapted.Item Earlier spring snowmelt drives arrowleaf balsamroot phenology in montane meadows(Wiley, 2022-08) Durney, J. Simone; Engel, Arden; Debinski, Diane M.; Burkle, Laura A.Climate change is shifting phenology globally, altering when and how species respond to environmental cues such as temperature and the timing of snowmelt. These shifts may result in phenological mismatches among interacting species, creating cascading effects on community and ecosystem dynamics. Using passive warming structures and snow removal, we examined how experimentally increased temperatures, earlier spring snowmelt, and the poorly understood interaction between warming and earlier spring snowmelt affected flower onset, flowering duration, and maximum floral display of the spring-flowering montane species, arrowleaf balsamroot (Balsamorhiza sagittata), over a 7-year period. Additionally, potential cumulative effects of treatments were evaluated over the study duration. The combination of heating with snow removal led to earlier flower onset, extended flowering duration, and increased maximum floral display. While there was year-to-year variation in floral phenology, the effect of heating with snow removal on earlier onset and maximum floral display strengthened over time. This suggests that short-term studies likely underestimate the potential for climate change to influence phenological plant traits. Overall, this research indicates that B. sagittata's flowering onset responded more strongly to snow removal than to heating, but the combination of heating with snow removal allowed plants to bloom earlier, longer, and more profusely, providing more pollinator resources in spring. If warming and early snowmelt cause similar responses in other plant species, these patterns could mitigate phenological mismatches with pollinators by providing a wider window of time for interaction and resiliency in the face of change. This example demonstrates that a detailed understanding of how spring-flowering plants respond to specific aspects of predicted climatic scenarios will improve our understanding of the effects of climate change on native plant–pollinator interactions in montane ecosystems. Studies like this help elucidate the long-term physiological effects of climate-induced stressors on plant phenology in long-lived forbs.Item Responses of Flowering Plant and Butterfly Communities to Experimental Herbicide and Seeding Treatments for Native Grassland Restoration(University of Wisconsin Press, 2021-08) Lyon, Nicholas J.; Stein, David S.; Debinski, Diane M.; Miller, James R.; Schacht, Walter H.Globally, grasslands are among the most degraded habitats, and within that category tallgrass prairies are especially threatened. To restore native species in tallgrass prairie, it is often necessary to concurrently remove exotic plant species while restoring the disturbance processes that many prairie taxa depend upon. Here, we coupled one herbicide application and seed mixture addition with tri-annual prescribed fire and annual cattle grazing to explore the consequences for floral resource (i.e., nectar-producing) plant communities and butterfly communities up to four years later. Each site was divided into three equally sized patches which were placed into either control, “spray-only”, or “spray-and-seed” treatment groups. We quantified both floral resource plant and butterfly communities in the year prior to herbicide application and the four years following that treatment. In the four years post-treatment, we found that floral resource abundance, richness, and diversity increased over time but did not significantly vary among treatments. No response to treatment was observed in butterflies, but butterfly abundance decreased while richness was stable and diversity increased over time, which may indicate that the changes to floral resources at the patch scale supported more speciose and diverse butterfly communities at the site scale. Butterfly abundance decreasing over time could be an effect of baseline management or unrelated regional factors. Regardless of whether either treatment benefited butterflies, we find support for a one-time herbicide application changing the floral community in desirable ways and at least not harming butterflies.Item Moderate Grazer Density Stabilizes Forage Availability More Than Patch Burning in Low-Stature Grassland(MDPI AG, 2021-04) Raynor, Edward J.; McGranahan, Devan Allen; Miller, James R.; Debinski, Diane M.; Schacht, Walter H.; Engle, David M.Spatially patchy fire creates landscape-level diversity that in turn stabilizes several rangeland ecosystem services, including forage production and habitat availability. To enhance biodiversity and livestock production, efforts are underway to restore fire regimes in rangelands throughout the Great Plains. However, invasive species such as tall fescue Schedonorus arundinaceus syn. Festuca arundinacea, initially introduced for forage production, hamper prescribed fire use. Grazer density, or stocking rate, modulates the effect of patchy fire regimes on ecological patterns in invaded, semi-natural rangeland pastures. We compare three diversity–stability responses—temporal variability in aboveground plant biomass, portfolio effects among plant functional groups, and beta diversity in plant functional group composition—in pastures managed with two different fire regimes through three periods of heavy, light, and moderate stocking rate in southern Iowa, USA. Pastures were either burned in patches, with one-third of the pasture burned each year, or completely burned every third year. The period of moderate grazer density had the least temporal variability in aboveground plant biomass, regardless of fire regime. We also found statistical evidence for a portfolio effect under moderate stocking, where diversification of plant communities through varying cover of functional groups can stabilize communities by reducing year-to-year variability. Beta diversity among plant functional groups was greatest during the moderate grazer density period as well. The short stature of tall fescue prevented the patch-burning regime to create contrast in vegetation structure among patches, and there was no difference in any diversity–stability mechanism response across the two different patterns of burning. Although longitudinal, these data suggest that temporal variability in aboveground plant biomass declines with diversity–stability mechanisms that underlie ecosystem function. Our results also support a decades-old principle of range management: moderate grazing intensity enhances diversity and stability, which has been shown to buffer forage shortfalls during drought.Item Evaluating Native Bee Communities and Nutrition in Managed Grasslands(2020-06) Stein, D. S.; Debinski, Diane M.; Pleasants, John M.; Toth, Amy L.Native pollinators are important for providing vital services in agroecosystems; however, their numbers are declining globally. Bees are the most efficient and diverse members of the pollinator community; therefore, it is imperative that management strategies be implemented that positively affect bee community composition and health. Here, we test responses of the bee and flowering plant communities to land management treatments in the context of grasslands in the upper Midwestern United States, a critical area with respect to bee declines. Twelve sites were selected to examine floral resources and wild bee communities based on three different types of grasslands: tallgrass prairie remnants, ungrazed restorations, and grazed restorations. Total bee abundance was significantly higher in ungrazed restorations than remnants, but there were no significant differences among grasslands in community composition or Shannon diversity. Across the three grassland types we also examined mass and lipid stores as nutritional health indicators in three sweat bees (Halictidae), Augochlora pura, Agapostemon virescens, and Halictus ligatus. Although there were no differences in lipid content, total average bee mass was significantly higher in Ag. virescens collected from ungrazed restorations as compared to remnants. Floral abundance of native and non-native species combined was significantly higher in grazed restorations compared to remnants and ungrazed restorations. However, ungrazed restorations had higher abundance and richness of native flowering ramets. These data suggest that bee abundance and nutrition are driven by high abundance of native flowering plant species, rather than total flowering plants.Item Using Satellite Data to Support Fieldwork: Can Species Distributions Be Predicted?(1996-07) Debinski, Diane M.Although species extinction has become a global concern during the last decade, our knowledge of species distribution patterns remains limited. If we don't know where a species has existed historically, we cannot determine if its range is contracting or expanding. This can make it difficult to identify a species as endangered until it is close to extinction. One way to address this problem is to try to predict which species may be at risk based on their habitat distributions.