Fish Ecology Field & Laboratory Assistant

Employer:  Joe Mrnak (; he/him) and Holly Embke (; she/her)

Description:  We are seeking two motivated and independent undergraduate students to assist on two whole-lake experiments in northern Wisconsin.

Experiment 1: Invasive species are a global concern, particularly for aquatic ecosystems. In Wisconsin, invasive rainbow smelt (Osmerus mordax) negatively affect ecosystems that they colonize through competitive and predatory interactions with native species. Negative effects include shifting food webs, altering zooplankton communities, and the decline or extirpation of native cool- and cold-water fishes (e.g., yellow perch Perca flavescens, walleye Sander vitreus, cisco Coregonus artedi). Understanding and mitigating these effects and associated consequences are of primary interest to managers and ecologists alike. Research will focus on characterizing the abundance, distribution, diets, and population dynamics of several fish species across multiple lakes.

Experiment 2: Fish communities in northern lakes of Wisconsin are changing; coldwater species are declining as warm water species are expanding. Understanding the drivers and consequences of these fish community changes are of primary interest to agency and UW aquatic ecologists. Research focuses on characterizing the abundance/distribution of several fish species and their prey resources during a whole-lake experiment. For more information on this project, see
For both projects, most of the work will be based in the field and may require long hours under sometimes adverse conditions. Fish sampling and habitat characterization will all be done via boat. Technicians will gain experience with several fish, limnological, and habitat sampling methods. Aside from these two projects, there will be multiple opportunities to assist and gain experience with other fisheries-based groups (e.g., WIDNR Escanaba Lake Research Station, UW-Stevens Point, NTL-LTER). Having students with different life experiences and backgrounds is critical to ensure the exchange of diverse ideas that is called for in training tomorrow’s scientists. Because we are actively working to increase diversity and inclusivity in our discipline, underrepresented groups are especially encouraged to apply.


  • Safe operation of UW – Madison boats and vehicles
  • Launching and towing boats
  • Careful data collection and sample processing
  • Deploying and retrieving sampling equipment
  • Handling and measuring fish
  • Conduct habitat surveys
  • Assist with field and lab equipment maintenance
  • Entering data into database


  • Must be eager to learn and have a genuine interest in aquatic ecology and(or) fisheries management
    • An aspect of this position will be an opportunity to conduct an independent research project (including giving an oral presentation) using data you collected
  • Maintain positive attitude while conducting work
  • Must be willing to work under sometimes adverse conditions (i.e., hot sun, cold, wind, rain, biting flies, etc.) for long hours
  • Be able to lift and carry a moderate amount (~30-50 lbs) of gear over short distances
  • Must be able to swim
  • Valid driver’s license which meets UW Risk Management standards is preferred.


  • Number of positions: 2 @ ~30-40 hrs/week
  • Start date: mid to late May 2021
  • End date: end of August 2021
  • Pay:  $11.50-no experience; $11.75-some experience; $12.00-very experienced
    • May also be selected for undergrad fellow


These positions are located at the CFL’s Trout Lake Station in Boulder Junction, WI in northern Wisconsin.   Dormitory style housing (not food) is provided free of charge. Enjoy swimming, hiking, fishing, biking and shoreline campfires while gaining valuable research experience!

How to apply:

  • Please send a brief cover letter and resume/CV as a single PDF to Joe Mrnak and Holly Embke via email (; Please include relevant field experience, course work, and research interests in your application package. For further details on these projects and positions, please contact Joe Mrnak via email or call 847-609-5123. We will be accepting applications until all positions are filled.

The CFL is an equal opportunity employer and is dedicated to an inclusive and positive working environment for all.