Stone Soup Frog Walk - 26 May 2024

Ten people, wearing raincoats and boots and carrying umbrellas, gathered in the rain at the entrance to Picnic Point for the scheduled Friends of Urban Nature’s Frog Walk.  Unbeknownst to us, the trip had been canceled, as it was down-pouring heavily.  
 
Doris Dubielzig, past Friends field trip organizer, learned that one family had come from Portage for the walk and quickly determined that two of the attendees, Amy Schleser of Lake Mills and AJ Sinkula, a UW student, knew frogs.  After a few introductions and orientation by Friends host, Diana Tapia Ramon, we splashed through the entrance, past the rain garden, and up the Point paths to Picnic Point Marsh.  A significant portion of the main path to the tip of the Point was barricaded closed, due to trees that had fallen during Tuesday night’s great thunderstorm.
 
At the Marsh, Diana advised us to be very quiet so that we could hear the frog calls through the sound of the raindrops.  Amy Schleser described the volunteer citizen science work that she has been involved with for the past year. As part of the DNR’s Wisconsin Frog and Toad Survey (https://wiatri.net/inventory/frogtoadsurvey/), she is helping to determine the status, distribution and long-term population trends of Wisconsin’s 12 frog and toad species.  Amy’s team goes out three nights a season, each about a month apart, to 10 specific locations where they listen for frogs and toads.  
 
AJ explained that because frogs and other amphibians absorb pollutants readily through their skin, they are important “indicator” species.  As amphibians are very sensitive to changes in the environment, their population sizes and trends provide insight into the health of the ecosystems they inhabit.  Alarmingly, frog populations around the work are declining each year.  Consequently, in addition to identifying amphibian species by ear, Amy estimates the population size of each species she hears. She also measures the temperature of the water at each of her assigned locations.   Today, AJ put on vinyl gloves, to keep from introducing anything hazardous to amphibian health, and ran her hands through the Marsh water, looking for tadpoles.  No luck.
 
From the Marsh, we walked to the edge of Biocore Prairie to see the Purple Martin House and Gourds, where a half-dozen Eastern purple martins flew off as we approached them.  Scott Hershberger explained that the Eastern purple martin, the largest member of the swallow family, nests almost exclusively in human-supplied housing.  Native Americans encouraged the birds to nest near their dwellings by providing gourds for the insectivores. 
 
We returned to the Picnic Point entrance, but most of the group continued to the Class of 1918 Marsh observation deck, hoping to see baby muskrats and to hear more frogs.  While we didn’t experience either of those, we saw a few muskrat houses among the cattails, and a lot of duckweed in the water.  Doris observed that common duckweed is the second smallest flowering plant in Wisconsin; the smallest is Wolffia.  
 
Like stone soup, this field trip succeeded with the good intentions and generous contributions of all who attended.
 
Report by Doris Dubielzig and photo by Diana Tapia Ramon

Participants listen to frog sounds in Picnic Point.