Diet breadth and foraging behavior
I am working on a federally-funded Multidisciplinary University Research Initiative (across 5 institutions) that leverages pollen DNA metabarcoding to quantify plant-pollinator interactions, pollinator foraging breadth, and pollen/pollinator origin in the context of global land use change. This metabarcoding skillset can be used to provide greater resolution to species interaction networks via molecular identification, and offers a wide range of ecological applications from tracking movement of organisms to identifying biogeographic origin using forensics. Currently, I am quantifying the impacts of urbanization on pollinator diet breadth in natural and agroecosytems using historic insect collections from the greater Austin area in combination with specimens I recently sampled for comparison. This will be the first of many projects integrating genomic tools with classical foraging and community ecology approaches to evaluate global change impacts on critical species interactions
Climate change in montane systems
Climate change and phenology: Phenology, the timing of life history events, is driven by abiotic factors, such as temperature, precipitation, and growing degree days. Changes in these abiotic factors under climate change can alter an organism’s phenology, which can have considerable effects on individual growth and reproduction, and ultimately drive changes in community composition. In plant communities, altered phenology can introduce plants to novel abiotic conditions during growth, such as increased exposure to spring frost events, and modify plant-pollinator interactions, both of which could drive changes in reproduction. Increasing temperatures under climate change have advanced the date of bare ground exposure in montane habitats, leading to an earlier onset of spring. As a result, montane plants that use snowmelt timing as their emergence cue have shifted their phenology to coincide with an earlier spring. Working with Dr. Rebecca Irwin (NC State) and Dr. David Inouye (University of Maryland) at the Rocky Mountain Biological Laboratory (RMBL) in western Colorado, I performed experiments to manipulate snowpack and frost exposure to simulate an earlier spring to determine how climate change will affect plant reproduction due to changes in phenology, growth, and plant-pollinator interactions
Bee response to climate change based on life history traits: Life history traits, which are phenotypic traits or behaviors that affect growth, survivorship, and reproduction, can shape how organisms respond to environmental change. Using eight years of bee monitoring data and > 20,000 specimens, I examined how bees with different life history traits, such as sociality, nesting behavior, size, and diet breadth, respond to changes in precipitation, snowmelt timing, and temperature. Further, in collaboration with Michael Stemkovski, we examined the abiotic drivers of bee phenology based on overwintering state and nesting behaviors. Both of these trait-focused studies have allowed us to understand which bees are responding most strongly to a changing climate and whether bees and plants are responding to similar environmental cues.
Bee response to climate change based on life history traits: Life history traits, which are phenotypic traits or behaviors that affect growth, survivorship, and reproduction, can shape how organisms respond to environmental change. Using eight years of bee monitoring data and > 20,000 specimens, I examined how bees with different life history traits, such as sociality, nesting behavior, size, and diet breadth, respond to changes in precipitation, snowmelt timing, and temperature. Further, in collaboration with Michael Stemkovski, we examined the abiotic drivers of bee phenology based on overwintering state and nesting behaviors. Both of these trait-focused studies have allowed us to understand which bees are responding most strongly to a changing climate and whether bees and plants are responding to similar environmental cues.
Pollination in prairie restorations
As the goal of habitat restoration is to create self-sustaining ecosystems, it is important to examine reinstatement of the pollinator community as many native plants rely on pollinators for successful reproduction. However, bee species vary in how effective they are at depositing pollen onto stigmas, thus abundance and richness estimates might not provide complete insight into whether seeded native plants are receiving sufficient pollination. Studies that examine pollinator effectiveness will enable land managers to optimize habitat for bees that are the most effective pollinators and maximize overall success of habitat restorations. In collaboration with Dr. Daniel Cariveau University of Minnesota) and graduate student, Ian Lane (University of Minnesota), I conduct studies in restored prairies throughout Western MN to examine pollinator effectiveness for two common prairie forbs. Further, in collaboration with Alan Ritchie (University of Minnesota) I study how burning, as a method of prairie management, affects phenology, pollinator visitation rates, plant growth and reproduction, and co-flowering communities of Dalea purpurea.
Undergraduate research (2008-2011)
Urban gardens
Urbanization is one of the greatest threats to pollinators due to loss of natural habitat and pervious surfaces for nesting. However, establishing pollinator habitats within urban areas can help mitigate habitat loss and conserve pollination function. In collaboration with Dr. Stacy Philpott (UC Santa Cruz), I examined how plantings of native vs. non-native gardens within urban areas affect bee communities and whether specific local garden and landscape characteristics correlate with changes in bee abundance and richness. My research demonstrated that native plants attract more visitors than gardens without native plants, and that local garden characteristics and the surrounding landscape are important drivers of bee diversity.
Coffee agroecosystems
In collaboration with Dr. Stacy Philpott and Dr. David Gonthier, I examined the effects of farming intensification on the tri-trophic interactions of parasitic phorid fly, its host-specific ant species Azteca instabilis, and the coffee berry borer, an economically damaging coffee pest. We also examined whether A. instabilis are effective biocontrol agents without a mutualistic reward from trees and whether other ant species prey on the coffee berry borer. Since the coffee berry borer burrows so deep into the berry that pesticides are ineffective at reducing infestation rates, the results from these projects highlight the importance of high-shade coffee farms on reducing parasitism rates of A. instabilis and maintaining high ant diversity to increase biocontrol effectiveness on pest populations.
Urbanization is one of the greatest threats to pollinators due to loss of natural habitat and pervious surfaces for nesting. However, establishing pollinator habitats within urban areas can help mitigate habitat loss and conserve pollination function. In collaboration with Dr. Stacy Philpott (UC Santa Cruz), I examined how plantings of native vs. non-native gardens within urban areas affect bee communities and whether specific local garden and landscape characteristics correlate with changes in bee abundance and richness. My research demonstrated that native plants attract more visitors than gardens without native plants, and that local garden characteristics and the surrounding landscape are important drivers of bee diversity.
Coffee agroecosystems
In collaboration with Dr. Stacy Philpott and Dr. David Gonthier, I examined the effects of farming intensification on the tri-trophic interactions of parasitic phorid fly, its host-specific ant species Azteca instabilis, and the coffee berry borer, an economically damaging coffee pest. We also examined whether A. instabilis are effective biocontrol agents without a mutualistic reward from trees and whether other ant species prey on the coffee berry borer. Since the coffee berry borer burrows so deep into the berry that pesticides are ineffective at reducing infestation rates, the results from these projects highlight the importance of high-shade coffee farms on reducing parasitism rates of A. instabilis and maintaining high ant diversity to increase biocontrol effectiveness on pest populations.