Research

Restoration of plants, pollinators, and their interactions

Habitat restoration, the active repair of lost or degraded ecosystems, is one of the best tools we have for protecting biodiversity in the face of widespread habitat loss and fragmentation. Restoration often involves the reintroduction of native organisms and historic disturbance regimes, but the long-term effects of such management is generally not well understood.

In my research, I use long-term observations of restored grasslands across natural and experimental landscapes to study the intersection between ecological disturbances and community assembly, landscape-level drivers of community change, and the reestablishment of declining species. My work focuses on two groups essential for the functioning of restored habitats, plants and their insect pollinators, with the ultimate goal of informing restoration management to better restore these important groups.

Restoration plot (50-acre burn) in central Texas

I use three study systems for this work:

Lady Bird Johnson Wildflower Center (central Texas) – For the past 20 years, researchers at the Wildflower Center have continuously monitored grassland plant communities across a replicated field experiment testing the seasonal effects of prescribed burning. I am using this powerful, long-term dataset to examine the effects of management on invasive species, plant compositional shifts, and restoration success.

Restorations across Cross Timbers ecoregion (northern/central Texas) – In 2018, ten working rangelands across Texas and Oklahoma were treated with prescribed burns (5 and 50 acres) and seeded with high-quality pollinator plants. As part of my postdoc at UT Austin, I studied the efficacy of these restoration methods across real-world landscapes by monitoring changes in plant and pollinator communities over time.

The Nachusa Grasslands (Illinois) – For 9 years, I have worked at one of the largest prairie restorations in North America, the Nachusa Grasslands, to examine how disturbance regimes interact with both local and landscape factors to drive shifts in ecological communities. In 2013, I established a long-term bee monitoring program across restorations of varying ages, disturbances, and landscape contexts, with the goal of studying community recovery of pollinators and their associated flowers. This is now among the longest-running studies of restored bee communities, which has allowed novel insights into long-term patterns in pollinator communities and declining species such as the endangered Rusty Patch Bumble Bee (Bombus affinis).

Restorations at Nachusa are seeded with up to 150 species of native plants,
and our team has found over 250 bee species across the prairie!

Pollinator movement and dispersal within restored habitats

The colonization of newly available habitats by functionally important organisms is essential for the success of restoration projects. However, little is known about the spatial and local characteristics that impact the ability of pollinators to locate and colonize restored land. A better understanding of dispersal process would allow practioners to better design habitats to encourage rapid establishment by pollinators.

To examine dispersal and colonization at a mechanistic level, I use a combination of landscape-scale experiments and novel methods for tracking dispersing bees and wasps across fragmented landscapes.

View looking down a corridor at the Savannah River Site habitat corridor experiment in South Carolina

I use two study systems for this work:

Savannah River Site Corridor Project (South Carolina) – During my PhD at Michigan State University, I used a landscape-scale fragmentation experiment to examine the effects of habitat isolation and shape on the movement and nest-building of solitary bees. Within a set of experimental landscapes composed of habitat patches differing in their connectivity and amount of edge, I conducted managed releases of the Alfalfa leaf-cutting bee (Megachile rotundata) to study their establishment and population growth in response to these spatial factors. I am also collaborating with students and postdocs to use these sites to examine the effects of corridors on pollinator community composition and wasp movement and predation.

KBS LTER (Michigan) – Since 1988, the MSU Kellogg Biological Station has run a prestigious Long Term Ecological Research project focusing on agroecology. Using both natural and agricultural patches within this ongoing project, I conducted another managed bee release to examine the effects of isolation and resource availability on bee colonization. I also collaborated with another student to examine the effects of floral abundance on bee movement and foraging behavior.

Nest block used in bee release experiments.

Effects of climate change on plants and pollinators in natural and restored ecosystems

Climate change is altering biological communities and species interactions worldwide. Widespread changes in temperature, precipitation, and extreme weather events have been shown to alter the emergence timing, ranges, and overall survival of both plants and pollinators.

My research focuses on identifying key drivers of community shifts in response to climate change and determining which species are most susceptible, to allow development of effective conservation strategies for protecting plants and pollinators in a changing world.

I use two study systems for this work:

Lady Bird Johnson Wildflower Center (central Texas) – With 20 years of observations, the long-term dataset from the LBJ Wildflower Center has the potential to provide invaluable insights into plant community response to weather patterns and climatic change. I am currently using this dataset to explore questions about how drought impacts invasion ecology and competition, and study the effects of drought duration and temporal windows on plant communities.

RMBL (Colorado) – In collaboration with a team from the Rocky Mountain Biological Lab (RMBL) led by Dr. Becky Irwin (NCSU University), I am studying how global climate change may affect bees and flowers in montane environments. Over the last 10 years, Dr. Irwin has monitored wild bee communities and their floral resources throughout each growing season to build an enormous long term dataset. Using this dataset, my collaborators and I are currently examining a number of topics including the population dynamics of bumble bees in response to fluctuations in floral availability and climatic variability, long term changes in bee phenology under projected climatic shifts, and the role of bee traits in determining species-level responses to climate.

Incredible flower diversity at the Rocky Mountain Biological Lab.