Thanks, Walt. Here, (Sonoma) where the rainfall was 170% of normal
and spring-like weather was a bit late by about two weeks, the
biophonies were down considerably, both as to density and diversity.
The pacific tree frogs were pretty normal. The black-headed grosbeaks
and robins were way down in numbers as were house finches (which only
had one breeding cycle) and goldfinches. Haven't seen any California
towhees nesting at all where we live (although they've been present
in considerable numbers a dozen years past). The pileateds are still
around in some numbers as are the great horned owls. Bats (myotis)
have fallen off considerably even though there are plenty of insects
flying around. Acorn woodpeckers and juncos were pretty normal as
were an abundance of red-shoulder hawks. The plain titmouse and
bushtit populations seem light as do the song sparrows and
white-crowns. No yellow-breasted chats this year, at all, and just a
few white-breasted nuthatches. Lots of Anna's hummingbirds. Not a
single chestnut-backed chicadee so far (which is unusual).
On our Arctic National Wildlife Refuge trip, taken in early June,
Martyn Stewart, Kevin Colver, and I were all commenting on how light
the biophony seemed to be at each of our very different sites. While
it's lighter than any time I've been on the tundra (5x previous),
this could be for any number of reasons. Natural dynamic shifts over
time, weather, late spring, etc. For a more typical sense of what the
tundra has sounded like in my experience you can hear a 90 second MP3
example at
http://www.wildsanctuary.com/java/applets/LivingLinks/audio/tundra.mp3
It was nothing like that this year.
I'm drawing no conclusions from this, other than to offer that it's
important to keep track of dynamic changes and to note them carefully
while we're in the field. Best way to do that is to record whole
biophonic samples while you're out there any way one can.
Bernie Krause
>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 =
year.
>>
>> 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
>
>
>
>
>
>"Microphones are not ears,
>Loudspeakers are not birds,
>A listening room is not nature."
>Klas Strandberg
>Yahoo! Groups Links
>
>
>
>
--
Wild Sanctuary
P. O. Box 536
Glen Ellen, CA 95442
t. 707-996-6677
f. 707-996-0280
http://www.wildsanctuary.com
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