Frog Song

One of my favourite signs of spring is the return of frog song. Ponds and wetlands across PEI are alive with noisy amphibians doing their best to attract a mate. Can you connect which of our four common frogs is making the sounds you hear?  

Photo 1: A Spring Peeper. This tiny frog has a big voice! Although only about the size of your thumbnail, this frog can be heard over long distances. Photo by Beth Knox, used with permission.

Spring Peepers are among the first frogs to be heard each year, and it’s hard to believe such a tiny frog makes that huge sound!  Peepers are only about 2.5 cm (1 inch) long – roughly the size of your thumbnail.  They can range from tan to red-orange, green, or fairly dark brown, but the distinguishing feature is the X-shape on the back (Photo 1 by Beth Knox, used with permission).  

The pond near my house is full of Peepers, and I’m always amazed at how instantly the chorus stops when I approach the pond. If I wait quietly for few minutes one brave soul will ‘peep’, then another, then a few more until everyone is back in action. Any movement on my part means silence on theirs. Despite the sound, I rarely spot them in spring and find it’s more common to see them once they move out of their breeding ponds and onto dry land for summer. Peepers have sticky toes that help them climb, and if you live near a wetland, you may be lucky enough to find one on the side of your house in late summer (or in your garden, as Beth did). You can hear a Spring Peeper here: https://www.torontozoo.com/adoptapond/audio/springpeeper.mp3 

Photo 2: The Wood Frog can be identified by its dark cheek patch, and has a call that sounds like a chattering duck. Photo by Donna Martin, used with permission.

Another tiny amphibian belting out its chorus right now is the Wood Frog (Photo 2 by Donna Martin, used with permission).  Roughly twice the size of a Peeper, Wood Frogs come in a range of colours including red, green, and brown.  Like Peepers, they have a distinctive marking that helps with identification, regardless of colour: that dark cheek patch. The Wood Frog’s call sounds much like a chattering duck, and their noises are often mistaken for waterfowl. Click here for an example: https://www.torontozoo.com/adoptapond/audio/woodfrog.mp3 

Photo 3: The Green Frog has spots that aren't always easily seen on darker individuals. However, the tympanum (ear drum, red arrow) and raised ridges on the back (yellow arrow) are distinctive.

If you’ve ever been near a wetland and noticed a sound resembling a banjo string being plucked, you’ve heard a Green Frog (example here: https://www.torontozoo.com/adoptapond/audio/greenfrog.mp3). These amphibians are about 7.5 cm (3 inches) long, and come in shades of yellow, green, and brown, with spots that can sometimes be hard to see on darker individuals (Photo 3).  The distinguishing features are the large tympanum (ear drum, red arrow) and the raised ridge that runs from the eye down the back on each side (yellow arrow).

Photo 4: A rare mutation in Green Frogs results in an absence of yellow pigment in the skin, resulting in a blue variation.

There’s a rare mutation in Green Frogs that causes the yellow pigment in the skin to be lacking.  Green is a mixture of yellow and blue, so without the yellow you get a blue Green Frog (Photo 4)! [I was sent this photo awhile back; if the sender reminds me who you are, I’ll add proper photo credit here]. 

Photo 5: The Leopard Frog has distinctive round or oval spots, each with a lighter halo around it. Photo by Donna Martin, used with permission.

Our fourth common species is the Leopard Frog, and you can see where it gets its name (Photo 5 by Donna Martin, used with permission). These green-coloured frogs are covered in dark round or oval spots, each with a light halo around it. PEI also has the much rarer Pickerel Frog, which looks a bit similar but is more brown than green and has long, rectangular spots. Pickeral Frogs have only been found in a few places east of Charlottetown.  The Leopard Frog’s call is a bit of a croak, often described as a bit like the sound of a finger being dragged across a balloon.  You can hear it for yourself here: https://www.torontozoo.com/adoptapond/audio/leopardfrog.mp3

As animals with permeable skin that use both aquatic and terrestrial habitats, frogs are sensitive to changes in their (and our) environment. They not only provide us with valuable pest control services, but also serve as early warnings about changes in ecosystem health. This spring, take some time to enjoy the local frog songs and appreciate these important parts of PEI untamed.