I have no idea to what extent salamanders and frogs moving through the woods
are detecting changes in wind, they may well be reacting more to changes in
relative humidity. When I was doing my Ph.D. I had to spend lots of nights
out checking traps as I had traps oriented in concentric rings around a
vernal pool and wanted to keep everyone going. I commonly observed that the
amphibians would abruptly halt their movements as rainy weather was replaced
by high pressure, accompanied by a drop in RH, increase in wind speed, and
usually a drop in temp. I have no idea exactly what signals they were
reacting to.
I have never read about salamander auditory abilities but am confident that
they hear quite a bit. I have long suspected that some salamanders may do a
fair bit of communicating through clicks and other subtle maybe infra or
ultrasonic calls but have no direct evidence for this.
One interesting thing relative to the discussion about amphibians moving
with and without rain - I know from a number of direct observations while
tending pitfall traps that wood frogs are prone to moving at times during
daylight hours with no rain in response, probably, to chorusing. One
anecdote will suffice - I set up the drift fence system that I used for part
of my Ph.D. studies around a pond in Concord, MA - finishing it on
3/15/1991. Some wood frogs and Ambystoma straggled in to the pond the next
two nights. March 17th was warm and sunny, much like yesterday (not as
warm, I think, as today) and I checked the traps in the AM and there were a
small number of amphibians despite a dry night. I processed and released
them into the pond and went home. Later in the early afternoon I got a call
from Tom French of MDFW telling me that someone had called to complain that
I was leaving frogs in my pitfall traps unattended. Surprised, I went out
to check and there were about 75 male wood frogs in traps that had moved to
the traps and been caught in the hours around noon or shortly afterward. It
rained that evening and I caught about 3,500 more wood frogs that night!
I have seen times when Ambystoma salamanders had clearly been moving during
daytime hours but that was much rarer - wood frogs are prone to it,
especially if not almost exclusively the boys.
Cheers,
Bryan
On Wed, Mar 16, 2011 at 11:02 PM, jacob.kubel <jacob.kubel@state.ma.us>wrote:
>
>
> Here's my stab at it...
>
> As I may have mentioned around this time last year, I find it difficult to
> believe that wind alone has much of an effect on salamander and other
> amphibian movement. In my experience, animals will be on the move even
> during a gale as long as there is a steady rain (or downpour). These guys
> are low to the ground and typically in the forest where they are not very
> exposed to wind. However, if you take the rain away, then amphibians seem
> less likely to move, especially if they need to cross an open area (e.g.,
> Bryan's golf course).
>
> Wind may have a direct effect on movement behavior in open areas where,
> even low to the ground, critters would be exposed to the drying effect of
> wind in the absence of rain. In forested habitats, though, the cessation of
> movement may be more a response to a drop in humidity than to the wind
> itself. If it is windy following a rain event, there is usually a drop in
> humidity associated with it (during spring in New England, at least).
> However, if there is not wind following a rain event, then humidity levels
> may sometimes remain suitable for amphibian movement, which explains why
> some movements still occur after the rain has ended. Hence, wind seems to
> become relevant only when the rain stops, but may just be a correlate of
> humidity.
>
> I do wonder, however, if wind may impact an animal's ability to orient . .
> .
>
> Jake
>
>
> --- In vernalpool@yahoogroups.com, Bryan Windmiller <bwindmiller@...>
> wrote:
> >
> > I've actually seen spotted and blue-spotted salamanders at the Concord
> > Country Club stop advancing towards their vernal pool breeding sites when
> > the rain stopped and the wind began to blow and then turn around and head
> > back into the woods.
> >
> > Bryan
> >
> > On Wed, Mar 16, 2011 at 11:39 AM, matt burne <mattburne@...> wrote:
> >
> > > I've certainly experienced wind having an effect, but I totally agree
> with
> > > Bryan's more nuanced explanation that as time marches on, those
> conditions
> > > which can put the brakes on earlier start to be less of a concern for
> the
> > > animals.
> > >
> > > I also agree that the big night myth is just that. I put a lot of
> energy
> > > and anxiety into getting people out for a spectacular event, when I
> know
> > > that it's maybe a 1 in 10 year thing to get a big hit (after supper and
> > > before bed time, naturally). Of course, the people that you have to
> drag
> > > out are usually a little less hard-core, may be less understanding of
> the
> > > nuances of the phenomenon, and not interested in a phone call at 2am to
> get
> > > boots and rain gear.
> > >
> > > Matt
> > >
> > > On Wed, Mar 16, 2011 at 10:36 AM, niccat6 <ncataldo@...> wrote:
> > >
> > > >
> > > >
> > > > > I've always been somewhat surprised by how the cessation of rain
> > > > > (particularly early in the season) stops the action in its tracks.
> > > > >
> > > > > Matt
> > > >
> > > > In my experience, wind has the same stop-everything effect, no matter
> how
> > > > good the other conditions and timing are. Would you agree, Matt,
> Bryan?
> > > >
> > > > N. Cataldo
> > > >
> > > >
> > > >
> > >
> > >
> > > [Non-text portions of this message have been removed]
> > >
> > >
> > >
> > > ------------------------------------
> > >
> > > Yahoo! Groups Links
> > >
> > >
> > >
> > >
> >
> >
> > [Non-text portions of this message have been removed]
> >
>
>
>
[Non-text portions of this message have been removed]
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