Today’s #FrogFriday is a double feature, profiling both the Upland Chorus Frog and the Southern Chorus Frog. These similar looking and sounding species will soon be the most dominant frogs calling; another sign that spring is on its way! Worried about them with all this cold and snow? Chorus Frogs are actually cold-tolerant species and are often heard calling when air temperatures are near freezing.
So, how can you tell these two seemingly similar frog species apart?
Location is a good starting point. The widespread Upland Chorus Frog may be found through most of Virginia’s Coastal Plain and scattered across the Piedmont and Mountain regions. The Southern Chorus Frog has a more limited range. Not discovered in Virginia until 2003, this species has only been verified in 6 of our southeastern counties/cities.
Markings can offer another distinction; most Upland Chorus Frogs have a dark triangle between their eyes, while Southern Chorus Frogs have 3 vertical rows of broken/blotchy stripes down their back. Time of day offers another consideration; both species are active at night, but Southern Chorus Frogs may occasionally be observed during the day as well.
Perhaps the best way to distinguish these two species is by their calls, but you will need to listen carefully. The Upland Chorus Frog’s “crrreek” or “prrreep” trill is often compared to the sound of running a finger along the teeth of a comb. While the Southern Chorus Frog’s call is similar, its trill is slower and jerky with each pulse distinct and countable. Some describe the Southern Chorus Frog as sounding like a cold/tired Upland Chorus Frog.
See if you can detect the difference between the Upland and Southern Chorus Frog calls using the sound clips below.
Upland Chorus Frog
Southern Chorus Frog
This is a part of our Virginia is for Frogs campaign, where we’ll be sharing a frog fact-of-the-week all year long.
Want even more frog facts and calls? Check out our Guide to the Frogs and Toads of Virginia, available from ShopDGIF.com, a 44-page field guide that covers all 27 species of frogs and toads that inhabit Virginia. Their calls have been captured on a high quality CD that can be easily listened to in the field, classroom, or at home!