Wood Frog
Lithobates sylvaticus = Rana sylvatica

  • markings:
    • medium
    • brown/tan
    • dark eye mask
  • call: chirdicks, chorus – raspy quack
Wood Frog

Boreal Chorus Frog
Pseudacris maculata (older field guides may show western chorus frogs, Pseudacris triseriata, for northern Illinois, but recent studies have revised the identity of our local species.)

  • markings:
    • small
    • 3 stripes on back
    • Black eye mask
    • March-May
  • call: like finger over top of comb
Western Chorus Frog

Spring Peeper
Pseudacris crucifer

  • markings:
    • small
    • X on back
    • March-May
  • call: high pitched “peep” chorus – sleigh bells
Spring Peeper

Northern Leopard Frog
Lithobates pipiens = Rana pipiens

  • markings:
    • medium
    • green w/dark circular spots
    • white lateral folds unbroken
  • call: soft course snore w/chuckle
Northern Leopard Frog

Plains Leopard Frog
Lithobates blairi = Rana blairi

  • markings:
    • green w/dark spots circular spots
    • white lateral folds broken near groin
    • SE & Will County
  • call: low chirks & snores
Plains Leopard Frog

Pickerel Frog
Lithobates palustris= Rana palustris

  • markings:
    • cream w/square spots
    • very rare – spring fed stream, fen or seep habitat
  • call: ticking snore “yeow”
Pickerel FrogPicture by Lalainya Goldsberry

American Toad
Anaxyrus americanus (older field guides may say Bufo americanus)

  • markings:
    • 1-2 warts per spot
    • large gland behind eye, unattached to bony crest, unless by a short spur
  • call: 10-30 second melodious trill
American Toad

Eastern Gray Tree Frog
Hyla/Dryophytes versicolor
Cope’s Gray Tree Frog
Hyla/Dryophytes chrysoscelis

  • markings:
    • lichen pattern (gray or green)
    • light patch below eye
    • yellow inner thighs
  • call: Eastern – musical trill
    Cope’s – fast harsh trill
Cope's Grey Tree Frog Cope’s Grey Tree Frog

Fowler’s Toad
Anaxyrus fowleri (older field guides may say Bufo fowleri)

  • markings:
    • 3 or more warts in large spot
    • large gland touches bony crest
    • sand habitat
  • call: distressed sheep
Fowler's Toad

Cricket Frog
Acris crepitans

  • markings:
    • small
    • triangle patch between eyes
    • warts
    • very rare near Chicago area
  • call: clanking marbles
Cricket Frog

Green Frog
Lithobates clamitans = Rana clamitans

  • markings:
    • large
    • green to brown
    • lateral folds 2/3 of body
  • call: banjo “gung”
Green Frog

Bullfrog
Lithobates catesbeianus = Rana catesbeiana

  • markings:
    • large
    • green to brown
    • lateral fold to ear
  • call: deep “br-wum”
Bullfrog

Unless otherwise noted above, all photographs were taken by Joe Cavataio and are used with permission.


Download Windows Media Player or Apple QuickTime Player to play frog calls .mp3 audio files if your PC doesn’t play these calls.


To download a list of frog calls, including multi-species choruses for your personal reference on your computer, mp3 player or smartphone, please click here.

Frog Calls are from the “Frogs and Toads of the Chicago Region” CD available to monitors for the Calling Frog Survey. The calls were provided by Lang Elliot, Music of Nature.