Posted by: "Wild Sanctuary"
> For those primarily recording the soundscapes of entire habitats
> (biophonies) in the Northern Hemisphere: Has anyone noticed changes
> this year in
>
> (1) creature voice density, and/or
> (2) creature diversity?
>
> By "density" I mean gross numbers recorded. By "diversity" I mean
> different species recorded.
>
> I'm especially interested in same sites where recordists go year after ye=
ar.
>
> Any observations would be appreciated. I'll share my impressions,
> also, but later.
Both Georgia and N Florida are in severe drought this year. Here at my
house we have recorded only 18" of rain for the year so far. Normal
annual total would be over 50" with most of that occurring by now.
I recently completed a foray down as far south as Sarasota, Florida. My
comments apply over that zone as well as local here.
In spite of the drought there is plenty of diversity of calls, except
maybe frogs. (on the other hand at my home the egg production of the
Gray Treefrogs is almost excessive, I'm having to put water in some
pools in the woods to give them a chance to make it.)
Voice density, particularly of insects is down. As one would expect in a
dry year. Birds at my home, and on the trip seem fairly normal. The deer
are more abundant at my home, generally a indication they have been
displaced by subdividers in the area.
The bluebirds at my home only did one round of nesting, but that's
probably the weather. In general the nesting on my property is about the
same as it has been for all species.
A pond that I use as a frequent nighttime test site in a wildlife
reserve about 30 miles S of here has mixed results as far as frogs
calling. Some species, mostly those that stay in or near the water have
been normal in numbers and calling. Others have hardly called. I was
last there two nights ago and three species were calling about normal
for this time of year. Some other ponds in the reserve are dry, so no
calling.
I've been frustrated by dry weather in confirming a new species of frog
for Georgia. My informant in S Georgia continues to watch and listen,
but it's all dust dry. I went through there on my FL trip. Last year I
was informed too late in the season to find the frogs. Looks like it
will be at least another year. Everything reported to me makes it look
very hopeful we will add a frog to the list.
I'm expecting diversity at my home to drop in the next ten years due to
rampant subdividing that's going on in my area. For those buying houses
it's a 50 mile (one way) commute to Atlanta. There are few jobs out
here. So far the diversity at my home has not changed from what it was
20+ years ago when we moved here.
Note that closer in to Atlanta the species diversity does drop,
particularly in the area of newer subdivisions where they are tending to
scrape it bare as a first step. Used to be they tried to preserve the
trees. This amounts to a large dead zone for wildlife, a fair percentage
of the Georgia piedmont gone. In Florida subdividers are gulping land
in huge blocks, packing in houses or trailer homes very close together.
The arctic refuge has much better chances than a lot of the lower 48 and
there are far less defenders down here.
Walt
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