I was pouring some Plaster of Paris the other day and made a discovery. I happened to be making some fake cupcakes, but that fact is neither here nor there as it relates to this discovery (other than the fact that cupcakes made out of Plaster of Paris are quite chalky). The point is that I was pouring a cup of freshly mixed plaster into a “mold.” Part of the procedure, when pouring P of P, is to jiggle the container or rattle it with a spoon. This keeps it liquidy and pourable, but this again is not crucial to the story (nor is the fact that liquidy is not a real word). I opted to rattle the inside of the plastic container with the spoon – an act which created a hollow “brrrrrr” sound. Instantly, our captive Leopard Frog started calling in response. “Brrrrrrrr” he croaked several times in succession before ending with a series of staccato “bup bup bups.” There was no doubt in his mind that I was a rival male.
I rattled the spoon again, and again our vociferous male responded in kind. He became suspicious after the third round of give and take and only managed a few indignant “bups” in return. He quit entirely after my fourth attempt at mimicry. My feeble efforts were no longer worthy of his consideration.
This particular frog, a lone dark male who has been with us for many years, has a reputation for answering all manner of challenges. He has responded to the sound of the refrigerator, the microwave, wet balloons, the sound of low voices, the recorded calls of other frogs, the sound of silence, and occasionally to the recorded calls of his own species! Unfortunately he is not entirely reliable in that last category. I have had a 50% success rate with my school programs when trying to get him to call by using a recorded Leopard Frog call. “Oh well kids, Spotty is not feeling up to talking today. Let’s turn on the microwave and mumble Gregorian chants to see if that works.” Now, at least I can pull out the Plaster of Paris cup and try the spoon trick.
Out in the wild, Spotty’s relatives are in the middle of their breeding season. They started calling in March, and will continue through to June, but April is the peak month for the “rut” (so to speak). Of all the calling frogs of spring, Leopard Frogs have the most understated approach. Chorus Frogs chirp, Peepers peep, and Wood Frogs cluck their way through the season with intensity and volume. Leopards, on the other hand, are minimalists. They snore their way through the love-making months with a subtle call that is barely audible to the human ear in an outdoor situation. It is one thing to have a love-sick frog calling from the inside of a reverberating aquarium, but quite another when that call is in competition with the wind and rustling grasses. The sound does not carry well.
I recently recorded a group of serenading Leopard Frogs in the shallow grassy floodwater next to a seasonal ditch. Not having my Plaster of Paris cup with me, I relied on chance to come up with some calling males. I was not disappointed. Well, actually I was a bit disappointed because I could not locate the actual callers. This species is known to sing while underwater, so watching them is like going to the submarine races. Listen here to a portion of the sonata (you won’t see any frogs here, but you will hear them – ignore the single creeking Chorus Frog ).
Yes, there were a few very cold individuals hopping about the shore, but these frogs were either non-calling females (like above) or just plain not calling (see below). Cold frogs are very easy to photograph because they are essentially non-responsive garden sculptures. If I had a video of a male leopard frog in the act of calling, you would notice that they are two baggers. In other words, they have two vocal sacs – one on each side that inflates over the shoulder. Being that I began this blog with a description of something unseen, I will not bore you with the details of yet another un-seen thing. Discussion of the egg-laying behavior will also have to wait for another time.
Before we leave this topic, however, it is worth taking a nice close look at the frogs I did manage to photograph. They are things of beauty. The two pictured frogs shown here are two different frogs. Take alternate looks at one then the other. Now the other then the first. Now the first and….stop. As you can see, the spot pattern is more hyena-like than leopard-like, but does that really matter? Given the growling nature of their call I can certainly see the leopard analogy. Leopard frogs don’t laugh.