(Emails from Colby Neuman  to the BirdTalk, 3 May 2008)

Hi all,

I hiked up Battle Creek (on the west side of Mt. Timpanogos) in Utah County early this morning. A number of RUFFED and BLUE GROUSE were drumming at dawn at about 7000' (where the trail comes out of the canyon and onto the bench). There were also apparent wing fluttery noises that I haven't heard before coming from multiple directions that I assume were Ruffed Grouse as well, but I'm not sure? ...

Colby

(Emails from Kris Purdy  to the BirdTalk, 3 May 2008)

Colby,

I suspect the wing fluttering noises you heard were from the Blue (Dusky)
Grouse. They occupy territories that are considered exploded leks, in other
words, individual birds space themselves far apart, but still within hearing
range of each other. Not only do Dusky Grouse hoot when they expand and
contract their cervical apteria, but they also do what's called flutter
flights or wing rips. The five-note hooting sound may not carry farther than
about 50 meters (so if you hear it, find that bird! You're close!), but the
flutter flights are almost a cracking flap and they carry far enough to be
heard by the other males in the area. The farthest distance I've heard a
wing rip that I know for sure was two-tenths of a mile.

When I've watched a particular male hoot, he would perform the wing rip in
response to another bird farther away that did it. Or the other bird would
hear my bird and I heard his responding wing rip. The grouse launches
himself into the air to a height of 3-4 feet and basically does a back flip
while flapping harder with one wing than the other. The uneven flap makes
him flip crookedly, but the wing motion is so strong and quick that the beat
is pretty loud and cracking. He lands in about the same place as where he
started.

The flutter flight also happens when the light is dim--either right at first
or last light. Researchers who have studied this have found that the males
perform the wing rip at a particular candle power of light. I've also heard
the rip when it was almost too dark to see above the snow line on the road
to Tony Grove Campground; the next sound (and sight) against the sky was the
grouse going to roost in a fir.

In addition to the hooting and flapping sounds, I've also seen three males
converge on a hen and "my" main bird made a resounding noise called the
pre-copulatory call. Officially, it's described as "Whoot", but my
interpretation (seriously) was "BOINK"! OK, you can laugh now.

Kris