I had a fantastic birding discussion over dinner this evening. It all
started with the request to name five species that would tend to be found in
different levels of a single tree. A little background here--the inquiry
came from someone working with hypotheses on how birders recognize birds
based on previous birding experience. What he wanted was a few scenarios in
which you might hear a bird that you would expect to be present in a given
level of a tree. After we came up with two "bird layered trees", he then
asked if the calls/songs from any one bird could be confused with another of
the birds.

This person works with priors and Baysian analysis applied to various
expectations, and he is envisioning a situation where you hear a bird and,
based on experience, initially look at a certain region of a tree. The
question about confusing calls is, of course, going to vary with each
birder's experience. We were chuckling over what an "expert" might think of
our saying that yes, some birders could confuse a brown thrasher with a
catbird, or a bushtit with a siskin. But the researcher realizes experience
plays a huge role in birding and is a variable that will be considered.

Interestingly, all three birders at the table started with a list of Eastern
species, I suppose because I stuck a catbird and a wood warbler in there
right away. We chose Brown Thrasher or Ovenbird for the ground level,
Catbird skulking around eye level, Blue-Winged Warblers above that, Scarlet
Tanagers above the BWW, and a Gnatcatcher at the neck-breaking height. Also
keep in mind that we thought of a towhee but couldn't agree about the height
at which it would normally sing/call. I think of the Eastern Towhee at
tending to sit higher up in trees than the Spotted Towhee, but that might
have been the region and available habitat where I birded most when living
East. We were also asked what species might be found calling or singing at
nearly all levels, and we came up with the American Robin, Yellow-Shafter
Flicker, Downy Woodpecker (the latter unlikely on the ground). We weren't
trying to be exhaustive. Of course, when we were asked what kind of tree,
we had problems. What tree would provide skulking cover for a catbird but
also possibly host the others? Well, we stretched it and suggested a
cottonwood, obviously focusing on deciduous in our bird selection.

I was thinking I couldn't come up with a similar scenario for this area, but
I suddenly pictured our neighbor's spruce and what I have seen there from my
kitchen window this spring. I thought of the following--Pine Siskins at the
top, Western Tanagers on the next layer, Black-headed Grosbeaks below,
Bushtits in the lower branches, and then we were stymied on the ground
level. We mentally transported the tree and came up with grouse/quail for
the lowest level (turkeys where introduced?), then thought of Juncos.
Juncos sing from higher perches but are generally still talkative when
feeding on the ground. Again, we thought of Towhees and Varied Thrushes,
but the VT would call from higher up, and the Towhees don't seem to like
conifers, at least these conifers. Starlings and Steller's Jays were
suggested as possible at all heights, and confusing calls could be (for some
birders), Bushtits vs. Siskins (and juncos, depending on expertise?),
Tanagers vs. Grosbeaks, and Starlings imitating jays. If we tossed in
Towhees, definitely Junco's vs. Towhees for the trills. We could also toss
Cedar Waxwings at the top with the Siskins

Perhaps this all seems crazy, but the question is being asked seriously in
order to build a basis for hypothesis development. If you want to suggest a
layered tree of calling or singing birds, or simply comment on our
selections, I will gladly pass on the suggestions. Feel free to respond in
private or to the group. It has been interesting having birding discussions
with someone who is analyzing identification tools and instincts from a
neutral perspective.

My cool sightings recently? A juvenile Dark-eyed Junco with a solid white
tail and a juvi Black-capped Chickadee with white outer tail feathers.

Thanks!

Doreen
Eastside
dorgilles at gmail.com
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