That first spring night when the marsh suddenly comes alive. Follow Michigan's chorus north, find a good night to listen and learn exactly who's making the noise.
Northern spring peeper · Sara L Giles, CC0Eastern Lower Peninsula
Temperature, wind, precipitation and recent wet days inform the opportunity index. It is a forecast for listening conditions, never a claimed audio detection.
100 = favorable weather for an in-season species, not a 100% chance of hearing it. No active species or incomplete weather = no numerical score. Weather can change quickly.
No Michigan frogs are in their calling window now. Learn the first voices of spring before they start.
Choose your location. The map changes seasonal timing, likely species and weather outlook. Markers represent forecast points, not actual frog sites.
Regional forecasts are not wetland-level measurements. Shorelines, tree cover, pond depth and winter thaw can shift activity substantially.
Typical windows shown for Saginaw Bay / Bay City, shifted broadly for north–south climate. These are guides, not verified 2026 starts.
Calendar endpoints are approximate editorial seasonal windows and should not be mistaken for observed calling start or end dates. Isle Royale's boreal chorus frog is a special case, not represented by the mainland regional forecasts.
See each frog and press Play to hear its real call. Recordings are from the USGS amphibian call library, plus two verified iNaturalist recordings for species USGS did not record.
Out of season · Mar–MaySoft quacking and clucking, like a flock of ducks
Photo: askalotl, CC0 · Call: USGS, public domain · Species profile ↗
Out of season · Mar–MayA rising raspy trill, like a fingernail drawn across a comb
Photo: © Chris McAnlis, CC BY 4.0 · Call: USGS, public domain · Species profile ↗
Out of season · Mar–JunPiercing single peeps; a full chorus sounds like sleigh bells
Photo: Sara L Giles, CC0 · Call: USGS, public domain · Species profile ↗
Out of season · Mar–JunLow snoring croak followed by short chuckles
Photo: © Patrick Hanly, CC BY 4.0 · Call: USGS, public domain · Species profile ↗
Out of season · Apr–JunShort low-pitched snore, softer than a leopard frog
Species of special concern: do not publish sensitive sites.
Photo: © John G. Phillips, CC BY 4.0 · Call: Kent P. McFarland, CC0 · Species profile ↗
Out of season · Apr–JulLong musical high-pitched trill, often 10–30 seconds
Photo: © Donald Davesne, CC BY 4.0 · Call: USGS, public domain · Species profile ↗
Out of season · Apr–AugSlow resonant melodic trill
Photo: USGS, public domain · Call: USGS, public domain · Species profile ↗
Out of season · May–JulA faster, buzzier trill than the eastern gray treefrog
Photo: © Audrey Witherington, CC BY 4.0 · Call: USGS, public domain · Species profile ↗
Out of season · May–SepA loose banjo string being plucked: gunk!
Photo: © Steven Joyner, CC BY 4.0 · Call: USGS, public domain · Species profile ↗
Out of season · Jun–SepDeep jug-o-rum notes
Photo: © gpete, CC BY 4.0 · Call: USGS, public domain · Species profile ↗
Northern speciesSeries of short low knocking notes
Photo: Matt Schultz, CC0 · Call: USGS, public domain · Species profile ↗
Special concern · local onlyShort nasal bleat, unlike the American toad trill
Special concern; habitat-dependent, not a statewide forecast.
Photo: © Sam Kieschnick, CC BY 4.0 · Call: © Moxie C., CC BY 4.0 · Species profile ↗
Threatened · local onlyMetallic click-click-click resembling two pebbles
Threatened in Michigan. No locality prediction or site pins.
Photo: © ramonsita625, CC BY 4.0 · Call: USGS, public domain · Species profile ↗
Every Play button uses a recording checked for species and licence (full media credits). Some taxa have restricted Michigan distributions. Fowler's toad is a species of special concern; Blanchard's cricket frog is threatened. No precise sites are provided. The DNR's official list includes both eastern and Cope's gray treefrogs, whose trills differ.
Match what you heard to a description, then press Play to compare. This is a listening aid, not automatic species recognition.
Northern spring peeperOne clear, high note, repeated about once a second. A big chorus rings like sleigh bells.
Western chorus frogA rough, rising trill a second or two long, like running a thumbnail along a comb.
Both call on the same cold early-spring nights, often from the same pond. Listen for a clean note versus a raspy trill.
Eastern gray treefrogA slower, musical trill. You can almost count the pulses.
Cope's gray treefrogA faster, harsher, buzzier trill. The pulses blur together.
They look identical, so the call is the only field mark. Warm nights speed both up, so compare frogs calling at the same time.
Green frogA single “gunk,” like plucking a loose banjo string, often one note at a time.
American bullfrogA deep, booming “jug-o-rum,” usually repeated several times and heard from far away.
Both call from permanent ponds on summer nights. Pitch and repetition separate them quickly.
No expensive gear required. A quiet wetland edge and a few minutes of listening are enough.
Try pond margins, flooded woods, roadside wetland edges and vernal pools. Stay on open public paths or your own property and keep out of sensitive breeding habitat.
Choose a mild night with little wind. Wood frogs and chorus frogs may call during the day too. Early spring calls can be loud for only a few nights.
Stand quietly for five minutes, then compare what you hear to the samples. Never collect frogs or enter a pond to get closer. Leave breeding sites undisturbed.
They typically start on mild spring evenings as thawed shallow wetlands become active. Southern Michigan can hear them in March and April; northern areas often follow weeks later. This tracker compares the seasonal window against local NWS forecasts and does not claim first calls without a recording.
Species differ. Early wood frogs and chorus frogs can call on relatively cool spring days while toads, treefrogs and bullfrogs generally favor warmer conditions. Temperatures in the forecast are a planning guide, not biological switch points.
Many frogs become vocal during mild, wet periods, especially around breeding ponds. Heavy rain, wind or thunderstorms can make listening difficult or unsafe. The forecast considers rain and wind separately.
A wood frog chorus sounds like ducks quacking or clucking. Compare it to the piercing peep of a spring peeper and the comb-like raspy trill of a western chorus frog in the listening guide.
A quiet evening after sunset is often productive, especially near shallow ponds. Some early spring callers also vocalize in daylight. Do not assume wetlands or parks permit entry after dark.
No. The 0–100 index is an editorial weather-fit comparison constrained by typical seasonal windows. It is not a measured chorus, a confirmed sighting, an abundance estimate or a numerical probability.
Eleven recordings are from the USGS ARMI frog and toad call library (public domain). USGS did not record the pickerel frog or Fowler’s toad, so those two calls are iNaturalist recordings whose identification was confirmed by other naturalists, shared under the licences shown. The Michigan DNR sound collection covers all 13 species and is the best place to keep practising. Volume is levelled so no call is startlingly louder than another; the calls themselves are unedited.
Forecast temperatures, wind and precipitation come from the National Weather Service. The recent rainfall and temperature context, when available, comes from NOAA Regional Climate Center ACIS. Species and recordings are based on Michigan DNR and the USGS amphibian call library.
What's modeled: regional calling windows and a 0–100 editorial evening-conditions index. What's not measured: microphone detections, first calls, frog abundance, water temperature, wetland water levels or calling probability. NWS forecasts update automatically, usually within 30-minute caches. A single representative station does not describe every marsh.
Last refreshed: Awaiting feed ET. There is no confirmed calling observation feed.