Current Research

Dom Ciruzzi: How do you study drought impacts in Wisconsin forests when 3 of the last 4 years (2019, 2017, 2016) have been the top three wettest years in the 115 year precipitation record? To answer this, I am developing a novel method with accelerometers to monitor continuous time series of tree sway as an indicator of tree water stress, canopy phenology, and interception. I am also leveraging long-term groundwater data from NTL-LTER and data encapsulated in tree rings to reconstruct historic groundwater and lake levels to understand how drought has differentially impacted forests with and without access to groundwater in the past.

Holly Embke: Walleye, a culturally, economically, and ecologically important sportfish in much of North America, has experienced declines in recent years. The cause of these declines is not understood, but is likely due to a combination of factors, such as temperature changes, harvest, and species interactions. As part of a multi-year project to understand the mechanisms underlying how Walleye are affected by other fishes, we will be conducting an experiment on McDermott Lake. We will remove as many bass and sunfish from this lake as possible to determine if there is an interaction between these fishes and walleye.

Kevin Gauthier: Temperature is a “master variable” in aquatic environments, driving fundamental biotic and abiotic processes. Scientists and managers are increasingly interested in measuring water temperature at multiple depths at high temporal resolution, yet the environmental sensing technology required to do so is expensive. We are designing, developing, and testing  temperature sensor strings that accurately measure water temperature every minute using open-source technology at a material cost of $220. Our construction of accurate, cost-effective temperature sensor strings provides evidence that scientists and managers may have an alternative to the use of expensive environmental sensing technology.

Dr. Gretchen Gerrish: I am an evolutionary ecologist that studies how organisms adapt to changing ecological conditions. My research focuses on aquatic invertebrates with unique life cycles and reproductive strategies that allow them to survive in variable environments. Currently, I am investigating how vertical migration behavior in zooplankton changes in relation to moonlight throughout the lunar cycle.

Dr. Susan Knight: In summer 2018, we investigated rings of water shield, (Brasenia schreberi), a floating-leaved aquatic plant, in the Huron Mountains of northern MI.  Though water shield commonly hugs the perimeter of lakes, the doughnut-shaped rings (“fairy rings”) in the middle of the lake is an unusual growth pattern for this plant.  We hypothesized the plants were missing from the center of the rings because of a cold-water spring, but tests revealed this was not the case.  We will return and continue to investigate this odd growth pattern.

Dr. Noah Lottig:I am an Assistant Scientist and Site Manager with the North Temperate Lakes Long Term Ecological Research Program. My primary research interests focus around ecosystem ecology and landscape limnology. I am particularly interested in understanding the long-term dynamics of aquatic ecosystems as well as the role aquatic ecosystems play in the regional and global carbon cycle.

Joe Mrnak: Invasive species are a global concern, particularly for aquatic ecosystems.  It remains unknown how food web configuration plays a role in the restoration of native pelagic systems and in the mitigation and control of invasives. We will be conducting two whole-lake experiments to test the hypothesis that food web configuration (i.e., presence or absence of a predator) influences interactions between native and invasive forage fishes.  To accomplish this, we will be stocking native cisco (Coregonus artedi) into Crystal and Sparkling lakes, which are currently dominated by invasive rainbow smelt (Osmerus mordax).  Crystal contains no predator and Sparkling will receive supplemental walleye (Sander vitreus) stocking.  We hypothesize greater rainbow smelt control and cisco reintroduction success in the system with predators (Sparkling) than without (Crystal). This study will have implications for future reintroduction and control efforts. Undergrad fellow Diana Tapia is assisting Joe in this research.

Charles Olmsted: Microbes dominate most of Earth’s biogeochemical cycles, especially those at work in aquatic ecosystems and doubly so in our LTER study sites, a smattering of bog lakes in northern Wisconsin. Members of the Microbial Observatory (MO), like myself, not only collect microbial samples and physical data for untold future LTER projects, but we also ask specific microbial questions. Our current obsession is Extracellular Electron Transfer (EET), and not just because biologically produced electricity is exciting. EET happens in most ecosystems on Earth, but our bog lakes are highly enriched for EET. One of our many questions is simply: why?

David Ortiz: As eutrophication of lakes continue to occur across the globe, there is a call to understand which lake characteristics are associated with blooming lakes. My project this summer focuses on FLAMe-ing lakes in the Northern Highland Lakes District that fall along a gradient of eutrophication. This research will improve our understanding of why some lakes undergo algal blooms and others do not. Sampling lakes with the FLAMe consists of collecting dense spatial data for a number of variables (e.g. algae concentration, pH, dissolved oxygen) across the water surface. 

Quinn Smith: My project focuses on coarse woody habitat addition (tree drops) to Sanford Lake and measuring fish community responses. This study will evaluate habitat use, short-term productivity, and food web dynamics in walleye (Sander vitreus), muskellunge (Esox masquinongy), and smallmouth bass (Micropterus dolomieu) in response to coarse woody habitat addition.

Dr. Carl Watras: We are investigating how lakes respond to changes in atmospheric pollutants derived from fossil fuel combustion. Although emissions of many pollutants have declined over the last 3 decades, the levels of contaminants in regional lakes and lake biota have not responded in kind. Instead, they’ve oscillated with the water cycle in ways that are often counter intuitive. This summer our focus is a sensor network maintained by citizen scientists to track how key elements of the water cycle vary from lake to lake. The goal is a broader understanding of how pollution levels are linked to climate variables.


Undergraduate Fellows

Emma Noraian: Over the last ten years, Wisconsin has experienced some of the wettest years on record. It is imperative to understand how this increase in precipitation is impacting the landscape in the context of a changing climate and changing land uses. Using GoogleEarth Historical Imagery, new lakes in the Upper Yahara Watershed were cataloged and their areas calculated. We found 163 new lakes that did not exist in 2006 but did in 2018. The total area of new lakes is equal to the footprint area of just over 620 Olympic-sized swimming pools or 155 football fields. This summer we will build on this data by cataloging the Lower Yahara Watershed, looking at other years, and using GIS to find and analyze this data to see how these new lakes will affect water resource management, agriculture, and hydroecology now and in the future.

Roger Ort: In past years, I contributed to the UW-Madison Microbial Observatory by regularly collecting microbial samples and physical data from bogs around the Wisconsin northwoods while at Trout Lake Station. This year I will be continuing my work by investigating Extracellular Electron Transfer (EET) in bogs and freshwater environments worldwide via data management and bioinformatics. I am particularly interested in how microbes that interact with iron in nature, such as iron-oxidizing bacteria, are involved in EET and redox cycles in bog environments.