From: Aaron Ximm <>
> So, I was in Zion national park this week chipping off the accumulated
> effects of a few weeks' too much work at the day job...
> ...and up in one of the side canyons had the good fortune to encounter a
> loud little bunch of what I think are canyon tree frogs, in a narrow
> slot canyon area, calling at dusk.
According to some pretty up to date detailed range maps I have the
Canyon Tree Frog is probably the only one to expect there. The Mountain
Treefrog has a range farther south. And the Pacific Treefrog slightly
The breeding call in your recording is very similar to some recorded
examples of the Canyon Tree Frog that are on a couple CD's I have.
> My wife and I sat with them and listened for a good hour or more, and I
> made several recordings, and I have a question for the frog experts in the
> In addition to the rather unbelievable jackhammer calls (I videoed one
> fellow beating his throat against the pool's rock wall, I'll post the vid
> if there's interest...), I noticed that not infrequently some distinct
> almost cat-meow like calls were made when one frog would swim over and,
> er, try to mount another!
> The latter were a most unexpected and comical set of anguished-sounding
> squawks -- when we first heard them my wife and I had a really hard time
> not laughing out loud and spoiling the recording(s)!
> I remember reading about "release calls" that one male frog will make when
> another inexpertly tries to mount him, the semantics of which I believe
> boil down to, "try your luck elsewhere, pal, I'm a guy too!" -- and was
> wondering if this could be an example?
> snip <
> More, and from different perspectives, on request... I hope you like this
> Walt! I was really thinking of you when I recorded it.
You were more fortunate than I, my route through Arizona was planned to
attempt to record both this species and the Mountain Treefrog.
Unfortunately, very strong winds and cold temps prevented that. Yours is
a nice recording.
If you observed this call directly associated only with mounting, it's
probably the release call. But, note that most frogs also have a
territorial challenge call. The call you recorded is fairly similar to
the territorial call of the Cope's Gray Treefrogs calling here. And, in
the case of your recording, it's being given with such frequency as to
make me wonder if it's the territorial call. The test would have been to
pick up a few males and grasp them as in amplexus and see what you got.
The release call is normally not given until grasped.
You can hear the territorial call of the Cope's Gray Treefrog mixed with
breeding calls on my frog pages, here's the direct link to the recording:
One of my long term goals is to record the release, territorial warning,
scream, rain and so forth calls for all of Georgia's frogs, not just the
breeding calls. Easy enough to do with something the size of a toad, but
think how you will grasp a Little Grass Frog to stimulate it's release
call (if it has one).
While I don't think it's the case here, there are frogs that are
communicating seismically. In those they are on mud and their vocal sacs
banging the mud create the seismic waves. The sound you hear in the air
is of no importance to them. The researchers working on that went as far
as building a piece of hardware to duplicate those waves and did attract
females with it. All a result of a scientist observing that the frogs
would hop away from him even when located where they would not see him.
Always good to watch what's going on, not just record.