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How the volunteer "frogger" group protects amphibians in Wisconsin waters

Wisconsin volunteer program helps keep track of frog and toad population
Wisconsin volunteer program helps keep track of frog and toad population 03:49

PRAIRIE LAKE, Wis. -- Frogs and toads face threats in rural areas, but there's a long-running volunteer program giving Wisconsin residents a first-hand experience in noticing and documenting changes to the amphibian population.

A "frogger" is what the Department of Natural Resources affectionately calls Robert Dass and the roughly 200-300 volunteers like him.

Dass, who works for a medical device company and is originally from Anoka, is in his second year as a volunteer frogger. 

The citizen scientists keep frogs safe by listening to and tracking their mating calls. 

"This time of year, we're looking for five or six different species in this particular region. So, that's what we're listening for," explained Dass. 

Dass visited 10 sites across his route in Star Prairie. His survey, a sort of amphibian census, requires a keen ear. 

"American toads sound a lot like grey trees frogs. Bullfrogs and green frogs sound similar," said Dass.  

With his clipboard in hand, and his ear cocked, Dass listened for five minutes, sometimes more at each stop. He went from swamp to swamp on his survey twice in the spring and once in early summer.  

The Wisconsin DNR trains the volunteers. 

"We give them a bunch of materials on how to learn each of the species calls before they go out," said Andrew Badje, conservation biologist with the Wisconsin Department of Natural Resources. 

That includes a CD featuring the "greatest hits" of mating calls. 

"Sometimes the chorus is just pretty to listen to," said Dass. 

This important work has been underway since 1984, making the DNR's Wisconsin frog and toad survey the longest running in the country. 

Collectively the volunteers have spent over 10,500 nights on these frog and toad call surveys. The data gathered answers a lot of questions for the DNR about their conservation efforts. 

"Do we need to flag certain species and keep an eye on them a little further? Do we need to track them? Do we need to list them or de-list them from state threatened/endangered status?" said Badje. 

It's working. Volunteers are documenting the highest levels of American bullfrogs, which were previously endangered. 

"We have a species called the Blanchard's cricket frog which is our only state endangered species and it's also endangered in Minnesota too. Volunteers have been really instrumental in tracking how they've been doing over the last 20 or so years," said Badje. 

A good sign that the state's efforts to protect these species are paying off. 

For more information on the frog and toad survey, click here.

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