Biotic Interactions & Climate

Project 1: warmXtrophic: Herbivory & Warming in Early Successional Fields

We are interested in understanding how biotic interactions and climate change directly and indirectly affect community structure and function. In particular, we are interested in how competition and herbivory interact with warming to affect early successional field community composition, phenology, and plant traits in Michigan. 
  • Lab members: Phoebe Zarnetske, Kileigh Welshofer, Nina Lany, Mark Hammond, Moriah Young, Kara Dobson, Kathryn Schmidt, Tori Niewohner, Elizabeth Postema, Amy Wrobleski
  • Funding: Michigan State University, University of Michigan Biological Station, Kellogg Biological Station REU Program
  • Publications: Welshofer et al. 2018 Oecologia, Welshofer et al. 2018 Methods in Ecology & Evolution
  • ​GitHub: https://github.com/plzmsu/warmXtrophic

Project 2: Multi-species distribution modeling

Species distribution models (SDMs) provide a means for forecasting species' distributions in space - both now and in the future during climate change. However, such correlative approaches commonly leave out biotic interactions and treat species individually. We incorporate biotic interactions among eastern hemlock, elongate hemlock scale, and hemlock woolly-adelgid, into multi-species (joint) distribution models with ordinal data. Biotic interaction strength can change depending on environmental context; we illustrate an approach to incorporating context dependency into SDMs with barnacles, mussels, and seastars in the Pacific Northwest rocky intertidal system.

A grant from the State of Michigan Invasive Species Grant Program focused on the recent invasion of hemlock woolly adelgid to Michigan, with the goals of (1) mapping current distributions of hemlock and hemlock woolly adelgid, and (2) forecasting the future spread of adelgid across the state based on cold tolerance and hemlock landscape connectivity.

Project 3: Climate and functional trait-mediated species interactions

Foraging traits could alter the strength of direct and indirect effects of climate warming. We are using microcosm experiments, in situ field experiments, and field surveys of ponds in southwestern Michigan to understand how rising temperatures will interact with predator foraging strategy to alter predator-prey interactions of freshwater invertebrates. We are using experimental results to parameterize mathematical population models forecasting how changing predator-prey interactions may alter invertebrate populations and the structure of freshwater food webs under different RCP climate change scenarios.​ With funding from NASA (NESSF), we are working to scale up these results to continental scales with the aquaXterra project described above. 
  • Lab Members: Laura Twardochleb, Phoebe Zarnetske, Ethan Hiltner, Tyler Treakle, Arpita Nayak, Faith Slubowski, Erika Ralston, Minali Bhatt
  • Funding:  Michigan State University ESPP, Kellogg Biological Station, Society for Freshwater Science
  • Publications: Twardochleb et al. 2020 Ecology
  • GitHub: https://github.com/aquaXterra/freshwater_insects_CONUS

Project 4: Arctic freshwater fish communities

We are using multivariate autoregressive models to investigate how freshwater fish body condition has changed in response to climate and biotic interactions over 30 years in Arctic lakes. Species include: lake trout, Arctic grayling, round whitefish, slimy sculpin, and burbot.