[birdky] RPT: Follow up on cicadas

From: "Palmer-Ball, Brainard (EPPC OOS KNPC)" <Brainard.Palmer-Ball@xxxxxx>
To: "BIRDKY" <birdky@xxxxxxxxxxxxx>
Date: Mon, 9 Jun 2008 10:24:58 -0400
I know this is a bird listserve ... if you're not interested in the
cicadas, just hit delete!
 
Since posting about the cicada emergence a week or so ago, I *think*
I've learned quite a bit more about the little rascals. First of all, I
think I now see why entomologists haven't studied too much concerning
where the three species occur within the overall range of emergence ...
because all three are present just about everywhere there are cicadas!
At first I thought maybe I was hearing only one species in a given area,
but now that the emergence of the brood is essentially complete and
everybody is singing, there have been only a few places where I have not
heard all three species if given a little time to listen. 
 
That being said, is seems that the larger, "phaaaaaaaaroh" singing
Magicicada septendecim is much more prevalent in eastern Kentucky and
the smaller, buzzy sounding M. cassini is much more prevalent in the
Bluegrass. 
 
The best combination of species I have heard is at Mammoth Cave National
Park and down in the hills northeast of Russellville, where all three
species, including the definitely less common, widespread, and
conspicuous, "chit-chit-chit-chit-chit-chit" singing, M. septendecula,
makes up a decent proportion of the singers in some spots. In these
areas, you can actually occasionally walk by a tree that has *mostly* M.
septendecula singing. This less common species is drowned out during the
afternoons up here in Frankfort was the M. cassinis din hits its max,
but you can hear a few in the morning and evening. So far I have not
seen or heard anything to suggest that the range map for this brood on
the Univ of Michigan web site is inaccurate. Interestingly, yesterday
morning I heard *only* single M. septendecim singing at each of 9 stops
on a BBS route I was doing in Washington and Floyd counties, Indiana.
 
One afternoon last week, while standing outside our office, Brian Yahn
and I witnessed a really neat behavior among a chorus of M. cassini.
Those who have heard the "pulsing" of their choruses know that the sound
ebbs and flows, sometimes in rhythmic fashion, almost hurting your ears
when it reaches its max. We noticed that during the short, two or three
second lull in the pulsing, that many cicadas in the tree were flying
from one spot to another, often just a few feet. When they landed, they
all sang at once again, creating the rhythmic pulsing of sound. As you
stared into the tree canopy, you'd see not a single cicada moving during
the peak sound, then all at once as the sound waned, dozens and dozens
of individuals would take flight in sort of a musical chairs routine,
landing somewhere else in the tree canopy, and resume singing for a few
seconds again. This happened at least a dozen times in a row and was
repeated in many of the other trees in our parking lot. REALLY cool.
 
bpb, Frankfort
[birdky] RPT: Follow up on cicadas

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