WHERE THE WIND BLOWS: THE ZOOPLANKTON WILL BE

Strong winds, high precipitation, and energetic storms are most common during spring months in temperate regions and are becoming more extreme and more frequent as the climate changes. These weather events can change long and short-term species distributions and trophic interactions in lake ecosystems. We hypothesize that weather events during spring and early summer months will change the horizontal and vertical distribution of zooplankton taxa, especially for larger species and larger-sized individuals. Additionally, we hypothesize that spring weather events and water column remixing will result in higher spatial variability in zooplankton distribution compared to stratified summer periods. To test our hypotheses, we sampled vertical temperature, dissolved oxygen, and chlorophyll-a. Zooplankton were also collected weekly from three sites in Escanaba Lake, Boulder Junction, WI, USA, using a Schindler-Patalas trap during the open water season of 2024. Zooplankton taxa were enumerated, and a subsample of Daphnia was measured from each sampling event to determine the size and species distributions. Early season weather events led to larger zooplankton species and larger-sized individuals accumulating on downwind shorelines. However, the type and duration of weather events interacts with migration behaviors to generate variable distributions of zooplankton. Seasonal patterns will be discussed within the context of overall seasonal plankton community changes and both vertical and horizontal zooplankton movement.

Presentation Preference: Poster

Primary Presenter: Jumana Tanner, Center For Limnology (jumanatanner13@gmail.com)

Authors:

Jumana Tanner, University of Wisconsin-Madison, Center For Limnology  (jtanner4@wisc.edu)

Gretchen Gerrish, University of Wisconsin-Madison, Center For Limnology  (ggerrish@wisc.edu)

Braden Richardson, Lawrence University, Department of Biology  (bradenrich4123@gmail.com)

Bart DeStasio, Lawrence University, Department of Biology  (bart.t.destasio@lawrence.edu)

Hilary Dugan, University of Wisconsin-Madison, Center for Limnology  (hdugan@wisc.edu)