Upland Chorus Frog

Written by Lang Elliott on May 3, 2010 · 3 Comments

May 2, 2010 in western Kentucky:

Major thunderstorms and gusty winds have raged across western Kentucky for the last three days, effectively delaying my work with birds. The one payoff: a couple of decent “frog nights” where I was able to collect some nice video and sound recordings.

On the night of May 1, I visited the Obion Creek Wildlife Management Area in the Mississippi lowlands near Milburn, Kentucky. There I focused my attention on a group of Upland Chorus Frogs (Pseudacris feriarum) calling from the edge of a flooded field next to the parking lot. Although a storm was blowing in and lightning was causing me some concern, I was able to get some very nice video clips (ultimately, a lightning strike nearby sent me packing!). Here are some highlights:

> HD version.

The call of the Upland Chorus Frog is described as a clicking trill that sounds like someone running their finger across the teeth of a comb. It is quite similar to the calls of a number of other chorus frogs, including the Midland Chorus Frog (Pseudacris triseriata) of the upper Midwest, the Boreal Chorus Frog (Pseudacris maculata) that ranges north into Canada, the New Jersey Chorus Frog (Pseudacris kalmi) found in New Jersey and surrounding areas, the Cajun Chorus Frog (Pseudacris fouquettei) of the mid-South, and the Southern Chorus Frog (Pseudacris nigrita) of the southeastern states. The calls of these species vary with regard to pulse rate (timing of clicks within a call), but they are exceedingly difficult to identify in the field because their pulse rates vary with temperature.

In the background of the video, you can hear a large chorus of Cope’s Gray Treefrogs (Hyla chrysoscelis). Here is the mix of sound of the two species, as I heard it when I pulled into the parking lot. Listen also for the occasional nasal calls of a single Fowler’s Toad:

Chorus of Upland Chorus Frogs, Cope's Gray Treefrogs, and one Fowler's Toad, Obion Wildlife Management Area hear Milburn, Kentucky, 10:30 pm, May 2, 2010.0:00 / 0:00

Treefrog Mates With Toad?

Written by Lang Elliott on April 25, 2010 · 4 Comments

Thunderstorms dropped heavy rain on western Kentucky on April 24, so I wasn’t surprised that frogs and toads burst into action that evening:

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The major species singing were the Cope’s Gray Treefrog (Hyla chrysoscelis), whose song is a brief rattling trill, and the American Toad (Bufo americaus), whose song is a long musical trill. Below I feature recordings of both. I also heard Spring Peepers and a few calls from Northern Cricket Frogs. I may have even heard an Upland Chorus Frog.

My real “catch of the night,” however, was finding a male Cope’s Gray Treefrog mounted on top of a male American Toad, in the mating position known as “amplexus”. Do these two species hybridize? Heavens no, and anyway, these are both males! Nonetheless, I presume the treefrog is happy with his catch, unaware that the liaison will not lead to procreation. Is the toad “happy” with the arrangement? I bet not—perhaps “annoyed” is a better word for his state of mind. One wonders why he doesn’t just “shake it off” and get on with his life:

> HD version.

Parallels with human behavior are obvious—misguided “attachment” contributing to a relationship that obviously isn’t going anywhere. Sound familiar?

RELATED RECORDINGS:

First off, here is a closeup of two male Cope’s Gray Treefrogs, with an American Toad periodically sounding off in the background:

Brief rattling trills of two Cope's Gray Treefrogs. Recorded by Lang Elliott at Land Between the Lakes, Kentucky, April 24, 2010, at 9:18 pm.0:00 / 0:00

Here is a clean recording of the melodic trills of an American Toad, the same toad that calls in the background in the above recording:

Calls of an American Toad. Recorded by Lang Elliott at Land Between the Lakes, Kentucky, April 24, 2010, at 9:18 pm.0:00 / 0:00

Here’s something special. In this chorus of Cope’s Gray Treefrogs, listen for occasional “chirping squeaks.” These are the aggression calls of the males, given by a an upset male when another male gets too close (I’ve marked the locations of the chirps with “x”):

Calls of Cope's Gray Treefrogs with aggressive chirps interspersed—chirps are marked with an 'x'. Recorded by Lang Elliott at Land Between the Lakes, Kentucky, April 24, 2010, at 9:15 pm.0:00 / 0:00

One last recording. If you were listening carefully when you watched the featured video, you will have noticed a Whip-poor-will singing in the background. Well, I chased him down and got a fair recording. It was a little breezy and there was a whooshy stream nearby, but this is special: my first whip-ppor-will recording of the season. I’ve been hearing them at Land Between the Lakes for two days now. Enjoy!:

Songs of a Whip-poor-will. Recorded by Lang Elliott at Land Between the Lakes, Kentucky, April 24, 2010, at 9:05 pm.0:00 / 0:00

Dream of the Toad

Written by Lang Elliott on February 19, 2010 · 5 Comments

> HD version.

Henry David Thoreau referred to the mating call of the American Toad as “the dream of the toad.” In his diary entry of October 26, 1853, he remembers back to spring and the day he first heard those magical sounds:

“I was going home to dinner, past a shallow pool, which was green with spring grass, and where a new house was about being erected, when it occurred to me that I heard the dream of the toad. It rang through and filled the air, though I had not heard it once. And I turned my companion’s attention to it, but he did not appear to perceive it as a new sound in the air. Loud and prevailing as it is, most men do not notice it at all. That afternoon the dream of the toads rang through the elms by Little River and affected the thoughts of men, though they were not conscious they heard it. How watchful we must be to keep the crystal well that we are made, clear!”

The song of the male is a long, melodic trill sometimes lasting thirty seconds or more. It is especially beautiful when heard at a distance. Each male in a chorus sings at a slightly different pitch. Songs in a chorus come and go and overlap one another to produce a dreamy, musical effect that is quite pleasing to the ear. As Thoreau so elegantly points out, one must listen carefully in order to hear the distant and often subtle dreams of the toads when they fill the air.

American Toads are found throughout much of the East (see range map) and breeding occurs after warm spring rains. When breeding is at its peak, excited males will grab almost anything that moves, in hopes of snagging a female. Wiggle your finger in front of one, and he will immediately clasp it with his forelegs. If a male grabs another male, the unfortunate victim will struggle to get to free, making squeaking “release calls” and vibrating his midsection, as if to say “let go of me, you idiot!” (see below for a recording of release calls).

Finally, when a receptive female approaches, the male will climb on top of her and clasp her tightly, his forelegs just behind hers—the classic frog and toad mating position called “amplexus.” The female, who is gravid (full of eggs), is usually much larger than the male. She then swims to an area in shallow water where she lays long strings of eggs, the male fertilizing them as they emerge from her cloaca. When egg-laying is done, the male releases his hold and returns to the chorus where he will continue singing in hopes of attracting another female.

The American Toad is an “explosive breeder,” meaning that breeding erupts quickly when the weather conditions are right—after warm spring rains—and may be over within a few days. This depends on the weather, of course, and breeding may be extended if conditions remain marginal over long periods.

What follows is a recording of a single trill followed by the squeaky release calls of a male that has been mounted by another male:

American Toad trill followed by squeaky release calls of a male mounted by another male. Recorded by Lang Elliott in upstate New York.0:00 / 0:00

Gray Treefrog

Written by Wil Hershberger on January 16, 2010 · 6 Comments

A chorus of frogs enlivens the night at Cool Pond in West Virginia. At this time of the season the chorus is dominated by Gray Treefrogs, Hyla versicolor, a species that occurs from Maine to Minnesota and south to east Texas and southern Virginia. This individual was singing from the lower branches of a willow at the water’s edge. Yarrow’s Honeysuckle berries gleam in the background.

I was wading knee deep in the pond to get to the location where he was singing. Getting the lights in place and the camera and tripod positioned without scaring him off was a task. He really tolerated my activities as he was consumed with other tasks. This video was shot with a Canon 5DII, 180mm macro lens using Cyclops LED lights. Audio was captured with a SoundDevices 702 and Sennhieser MKH 20 microphones.

Gray treefrogs can be very well camouflaged when they are sitting in their environment. Below is a photo from David Lapp that shows just how well a Gray Treefrog can vanish into the substrate.