Ecological Research

Most projects in the Cottingham lab have tackled ecological research questions, typically in freshwater lakes and ponds.  For a sampling of past papers, click here for a Google Scholar search for papers Kathy has co-authored.

Our current ecological projects include:

  • The “Gloeo” Project:  Gloeotrichia echinulata, the beautiful colonial cyanobacterium shown below, is increasingly reported from low-nutrient lakes across Northern New England and adjoining regions in Canada. In collaboration with Cayelan Carey at Virginia Tech, Kathie Weathers at the Cary Institute, Holly Ewing and Meredith Greer at Bates College, Denise Bruesewitz at Colby College, and Dave Richardson at SUNY – New Paltz, we are working to understand the causes and consequences of these recent increases for lake plankton communities and ecosystem functioning (including phosphorus, nitrogen, and carbon cycling); reconstruct past abundances using paleoecological records; and generalize from what we are learning from our long-term studies of this species to the general problem of cyanobacterial response to global climate change.

    Gloeotrichia echinulata

    Gloeotrichia echinulata

Ongoing field observations in Lake Sunapee, NH, are a key component of this project – keeping Kathy in the field at least once a week since 2007 and generating endless stories (and photos!).  To date, we have combined statistical analyses of these long-term data (e.g., Carey et al. 2014) with short-term field experiments and difference and differential equations models (e.g., Greer et al. 2013); next steps include analyzing the daily time series generated by our citizen science partner and adding agent-based models and laboratory experiments in limnotubes to our repertoire to get at more mechanistic questions.

  • Investigating the landscape limnology of Greenlandic lakes and ponds:  This project includes three key components:  (1) understanding the distribution, abundance, and ecological importance of colonial Nostoc cyanobacteria in lakes; (2) quantifying cyanobacterial toxicity in these waters and evaluating whether there are landscape- or lake-specific factors that contribute to observed toxicity; and (3) determining whether cyanotoxins are passed into other aquatic organisms or even onto land.  The on-the-ground work for this project has been conducted by graduate student Jess Trout-Haney, who has spent at least a month each summer in the field collecting data and samples. This work is currently funded by a Dartmouth Scholarly Innovation and Advancement Award and a National Science Foundation JSEP grant awarded to Ross Virginia and Lauren Culler.  Undergraduate Precious Kilimo ’18 has helped Jess with lab studies evaluating toxin release by Nostoc.  In the past year, Jess’s work has been written up in Eos and Lake Monitor.
  • Evaluating how thermal environments affect the performance of individual organisms and populations.  Visiting postdoctoral researcher Sam Fey and undergraduate Aldo Arellano ’17 are studying thermal adapation in the green alga Chlamydomonas in the laboratory, while grad student Keith Fritschie is busy setting up a research program to understand how stream temperatures — as influenced by groundwater inputs — impact the very early life history of native brook trout in the streams of Vermont and New Hampshire.  See Keith’s website for more details.
  • Determining how methylmercury exposure alters the physiology and behavior of stream crayfish populations.  Studies of the effects of methylmercury on invertebrate neurobiology and physiology are still in their infancy, and our newest graduate student Andrew Vacca seeks to fill that gap. Andy is currently developing protocols to evaluate crayfish predator avoidance behaviors in natural and lab-reared populations that have been exposed to varying concentrations of methylmercury in their diets.  See Andy’s website for more details.