bbystrek wrote:
> Does anyone have any advice recording wood frogs? Last spring was my
> first experience hearing these frogs - They have the most unusual
> voices of the ten frogs and toads that call Connecticut home. They
> are supposed to be one of the earliest breeders here in Connecticut
> as they are said to use temporary pools which dry up by early
> summer. I just started learning nature recording last spring, just a
> little too late to catch them.
I'm in Georgia, wood frogs barely make it into the northern part of
Georgia, so they are fairly uncommon to locate here.
> Is it right that they typically only breed for a few days a year?=20
> Some of the texts I found so far seem to conflict on this point.
It is the more common report that they only call briefly.
However, a few years ago I set out to do my own little check. I returned
again and again to the same few sites to check the calling wood frogs.
At one site they called every time I was there for 2 1/2 months. The
last time at the beginning of May. This was not some few hanger's on, it
was a full chorus as eager sounding from beginning to end.
> I heard a wonderful chorus on the first evening I discovered them.=20
> Two failed attempts recording them on return visits a couple days or
> so later seemed to suggest that were very sensitive to ground
> vibration or had better eyesight than me as they stopped calling for
> longer than my patience and nerves could hold up (same evening a
> beaver scared the wits out of me as it began briskly chewing on a
> tree probably thirty feet away). Another theory was that on my
> second and third visits the temperature was rapidly dropping and they
> simply did not start back up because it had grown too cold.
I've gone into a wood frog chorus, caught a few for photography, and the
chorus was calling by the time I was 30' away. They don't seem overly shy.
I've recorded them from 20 to 30' away with no problems.
Coldest I've heard them call was in the low 30's.
> Could wood frogs possibly have a really long cycle to their chorus?=20
> Don't some frogs have periods of peak activity where the chorus rises
> and falls on something like a 30 minute period? I noticed some
> obvious response to jet rumble with another species, Hyla versicolor
> (gray tree frog), where they stop calling for a few minutes as the
> jet noise peaks. I'm pretty sure I was seeing the same thing with
> Bull Frogs. Of course disruptions, people or otherwise, don't seem
> to matter as much when the chrous is really active.
Many frogs seem to be set off calling by the vibrations of passing cars
and such like. It's pretty rare that such vibration had the opposite
effect in my experience. Very annoying for nature recording to only have
them call when a car is passing, but I've had that happen with a number
of species.
Frogs in a chorus are often responding to each other. So, if no one is
calling it can stay that way for a while. Then one will call somewhere
and it grows. I have seen that sort of cycle, but nearly always a lot
shorter period than 30 minutes. The wood frogs I've been at have mostly
called steady or near steady, no long breaks.
Now, the Pine Barrens Treefrog down here tends to call in small groups
and each group calls for a few minutes and then is silent for 15 - 20
minutes or longer before repeating. And it's been reported that if there
are several groups in a area that the entire groups may take turns.
Makes them a tricky one to track down.
Part of the fun of nature recording is learning the habits of your
subjects. They definitely have patterns. If this was simple and easy it
would not be near as much fun.
Walt
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