Forest Preserves of Cook County 2025 Spring Brochure

A RIBBIT RHAPSODY: Frog Calls of the Forest Preserves As the ice thaws and ponds come alive, the Forest Preserves of Cook County transforms into an energetic amphitheater of frog calls. These springtime serenades are a sign of the changing seasons—when our frogs first thaw from their winter torpor and begin calling loudly to attract a mate. Here’s a guide to the voices you might hear in the preserves and how to mimic their calls at home. Northern Leopard Frog (R. or L. pipiens) The northern leopard frog looks like the pickerel frog, but its blotches are round, rather than rectangular. It breeds from mid-March to May with its distinctive, deep and resonant snore occasionally punctuated by clucking. The northern leopard frog’s call compares to the sound when you rub your thumb across the surface of an inflated balloon. 24 A RIBBIT RHAPSODY: Frog Calls of the Forest Preserves As the ice thaws and ponds come alive, the Forest Preserves of Cook County transforms into an energetic amphith a er of frog calls. These springtime serenades are a sign of the c anging seasons—when our frogs first thaw from their winter torpor and begin c lling loudly to attract a mate. Here’s a guide to the voices you might hear in the prese ves an h w to mimic their calls at home. Northern Leopard Frog (R. or L. pipiens) The northern leopard frog looks lik the picker l frog, but its blotches ar round, rather than rectangular. It breeds from mid-Mar h to M y with its distinctive, deep and resonant snore occasionally punctuated by clucking. The northern leopard frog’s call compa es to the sound when you rub your thumb across the surface of an inflated balloon. 24