Beyond Birdsong

Beyond Birdsong

As summer approaches, we may begin to notice a decline in bird activity. Migration is over for now, most year-round and summer residents are nesting, and dawn choruses are less dramatic than months ago. In fact, most mornings only bring the sounds of cardinals, catbirds, vireos, wrens, and a few of  our warbler. This is a good time of year to experience the other voices of our woodlands, meadows, and gardens. 

Songs of Nature 

Birds are not the only animals that sing during the spring, summer, and autumn months. In addition to our feathered friends, frogs, katydids, crickets, cicadas, and even certain mammals have calls and songs of their own. When birds go silent for the summer, these animals will take their place. In the Cape Fear Region, there are 23 species of frogs, 8 species of cicadas, and many  katydid, cricket, grasshopper species. While it will be difficult to learn all of these songs, it is still fun to experience the choruses of these often overlooked creatures.

Part One: Frogs 

Home Water Garden circa 2010, a good way to attract frogs

This week we are going to focus on our amphibian vocalists. Frogs and toads are already famous for their voices and nearly all species make some sort of sound. Most people know of the generic "ribbit" sound heard on cartoons, garden decorations, or toys. In reality, frogs have more complex voices and are arguably as beautiful and diverse as the songs of birds. Each of our 23 frog species have their own set of calls and with a good CD, online site, or some outings with herpetologists we can learn most of our common species in short order. Frogs and toads may sing any time of the day or night, but are most likely to be heard before, during, or just after rainstorms. In our area, frogs can be heard any time of  the year although each species has its own window. Like birds, frogs and toads sing to announce their territories, and attract mates. Some species can sing throughout the year, while others sing only when they are mating, allowing only a small window to experience their sounds. Frogs are a good starting place for beginners as our garden as many of the familiar species have distinctive calls.

Notable Frog Species in the Cape Fear 

A Copes Grey Treefrog in our garden 

Southern Toad Bufo terrestris: A familiar species of toad that is often seen in our gardens throughout the year. This is the type of "frog" that we dig up in flowerpots or garden beds during the winter. Breeds in lakes and creeks. Sound is a long trill call that lasts for 20-30 seconds or longer. During the spring and summer, entire groups of toads can be heard around lakes, ponds or puddles after heavy rains. Listen here 

Fowler's Toad  Bufo fowleri: A fairly large toad species that is similar to the Southern Toad except for its call. Found in similar habitat to Southern Toad including our gardens. Call is a loud screaming call not unlike a scream in a horror movie. Listen here  

Southern Cricket Frog Acris gryllus: A fairly common species that breeds in the spring and summer. This specie is likely to be encountered in wet meadows, ditches, and along lakeshores as well as home water gardens. Cricket frogs make a clicking sound similar to a cicada or katydid. Listen here

Cope's Grey Treefrog Hyla chrysoscelis: The Grey Treefrog is a common species in the Cape Fear and this is one of two species that occur in North America. The Cope's is the only species found in our area. Look for these frogs in shade trees, amongst lichens or around shrubs, tree, and planters in our garden. Song is a loud rattle that may be familiar due to its use in many jungle or creepy horror scenes in films. Listen here

Green Treefrog Hyly cinerea: The Green Treefrog is likely our most frequently encountered frog and is one of three species that readily occurs away from water. This fairly large treefrog can be seen any time of the year and is bright green with white stripes. They occur in virtually any habitat from marshes and meadows to urban dooryards. They breed in any permanent body of water including home water gardens. Song is a loud croaking sound that has a distinctive twang. Groups of frogs may sound like someone using a handsaw. Listen here

Squirrel Treefrog Hyla squirella: The Squrrel Treefrog is a smaller lookalike to  the Green Treefrog and but can change color, just like our anoles. This frog is much smaller than other species and can be lime green, yellowish, spotted brown, or even grey. This is the treefrog that often enters our homes at night, and is found in any wooded or marshy habitat in our region. They breed in both permanent and ephemeral ponds without fish. Their song is a loud "whawk whawk" call that sounds like a duck, or a faster chatter. These calls are often heard during the day or during thunderstorms. Listen here

Barking Treefrog Hyla gratiosa: The Barking Treefrog is our treefrog and is almost the size of a toad. This frog is found near lakes, ponds, or rivers in savannas, swamps, and forests. Most examples are bright green with spots or are darker green and may change color like the Squirrel Treefrog. It also occurs in gardens and parks with water. They make a loud barking sound similar to a distant dog. Listen here  

Pinewoods Treefrog Hyla femoralis: The Pinewoods Treefrog is another greyish or brown species that looks like the Grey Treefrog or a brown morph Squirrel Treefrog. This frog is mostly found in pinelands, wooded swamps, and peatlands with temporary  wetlands or ponds without fish and is rather common at Halyburton Park, Carolina Beach State Park, and Holly Shelter Gamelands. Its sound is a low pitched ratcheting sound that sounds like Morse Code. Listen here  

Spring Peeper Pseudacris crucifer: The Spring Peeper is our earliest species of frog to breed and is most likely to be heard during rainstorms from mid-autumn to spring. The frog itself is difficult to find outside of breeding and is a tiny (about 2cm or 1" long). Adults  are greyish brown or pinkish but vary in coloration. It occupies woodlands, hedgerows and marshes where it is found in leaf litter, under logs or stones. Ponds, lakes, and ditches are normal breeding areas although this species may use a garden wetland as well.  Song is a high pitched "Peep" that goes on continously and is comparable to nestling birds. Listen here

Southern Chorus Frog Pseudacris nigrita: The Chorus Frog is another small species that is more often heard than seen and is related to the Spring Peeper. This frog is mostly found in pinelands, baylakes, roadside ditches, or in depressions in wet meadows. It breeds from late autumn to spring and is often difficult to find outside of breeding season. The Brimley's Chorus Frog Pseudacris brimleyi is less common and is dark brown. Its song is a trill that sounds like someone turning a crank or other tool. Listen here

Grass Frog Pseudacris ocularis: The Grass Frog is our smallest species of frog that is around 1cm (or a half of inch") long and is dwarfed by many insects. These frogs can be seen during the warm season in wet meadows, peatlands, marshes, open forests, or pinelands as well as in gardens. Grass Frogs can be grey, brown, orange, or reddish. It breeds mostly in fish-less ponds or temporary wetlands including persistent rain puddles or depressions that last for at least 45 days.  Its call is a high pitched clicking sound "crik-it" that sounds like a cricket or glass bottles clinking together. Listen here

American Bullfrog Rana catesbeiana: The Bullfrog is the largest frog species in North America and is the generic frog depicted in cartoons, movies, children's books, or decorative garden statues.  The frog can be as large as 20cm or 8 inches long and will eat almost anything it can swallow, including small songbirds. The frogs can be green, grey, or brown with spots but are told from toads by its webbed hind feet.  Bullfrogs are found virtually anywhere with permanent water including ponds, creeks, depressions, and in garden ponds. They readily visit swimming pools and may be found in meadows or gardens away from water. This species is active year round. Song is a loud moaning call that sounds like a someone starting a lawnmower or distant foghorn and is often written as "Jug-o-Rum". Bullfrogs also make a whining sound when grabbed. Listen here

Green Frog Rana clamitans: The Green Frog or Bronzed Frog is another familiar species that is found near lakes and ponds. It is smaller than the Bullfrog and is green, brown or greyish with spots. This species is often seen along roadside ditches, wetlands, and water gardens and is often found away from water. Its calls include a squeaking sound that is often heard when they are startled, while the song  sounds like a notes being played on a stand-up bass (essential for any good jazz standard). Listen here  

Pickerel Frog Rana palustris: The Pickerel Frog is a fairly small pond frog that is brown or greyish with dark spots that are arranged in two rows on its back. It is found during any month of the year and is common in peatlands, ponds, ditches, and freshwater marshes.  Like the Bullfrog and Green Frog, they can be found away from water and may breed in garden ponds. This frog produces skin toxins when stressed that may kill other amphibians if kept in the same aquarium while captive. The call is a long snore that may be given underwater. Listen here

Leopard  Frog Rana sphenocephala: The Leopard Frog is a common species that can be seen any time of the year but is distinguished from the Pickerel Frog by its smaller spots, and yellow. They can be greenish, brown, or tan. This frog is found in virtually any wetland but is most successful in fish-less ponds, ephemeral wetlands, or in home water gardens and manmade wetlands. They are often found away from water and turn up in gardens or grassy fields at times. This species makes a chuckling sound that sounds a bit like a squirrel or even a calling Anhinga. Listen here

Carpenter Frog: Rana virgatipes: The Carpenter Frog is an elusive but fairly common frog that is associated with riverine habitats, peatlands, beaver ponds, and tea colored waters of the Cape Fear and other river systems. They may also be found in ponds, and other wetlands.  It is highly aquatic. This species is brownish or bronzed with green spots and is similar in size to a Leopard Frog. It breeds in the spring and summer and the tadpoles are tolerant of acid. Call is a two-note clacking sound with a hollow or woody tone. This frog was named because its song is compared to a carpenter hammering wood or perhaps a nail gun at a construction site. Listen Here

Thank you for reading. I hope to do a similar article about singing insects at a later date with Cicadas being the main focus due to their distinct calls. 

Good frogwatching Resources

Amphibians  and Reptiles of North Carolina. herpsofnc.org. 

Savannah River Ecology Laboratory at the University of Georgia. srelherp.uga.edu/anurans/index.htm

Books

Amphibians & Reptiles of the Carolinas and Virginia by Jeffery C. Beane, Alvin L. Braswell, Joseph C. Mitchell, William M. Palmer, and Julian R. Harrison III.