Given half a chance, birds are survivors. They are much better at
optimizing than we are.

I've noticed a clear pattern at the feeders outside my window. There
is a tube feeder stuffed with sunflower seeds and a suet holder
stuffed with suet. They are on a post with a raccoon guard so envious
gray squirrels can't get to them. They have been a scene of constant
activity since the weather turned cooler. The House Finch "swarm" can
finish off the sunflower seeds in a day or so, so there are often
intervals when there are no accessible seeds in that feeder.

Both Red-breasted Nuthatches and Chestnut-backed Chickadees routinely
stop at the suet feeder, tank up on at least a few bites, then go
over, get a sunflower seed, and fly away. Clearly they are combining
feeding strategies at one stop-and-shop. The suet is for instant
energy, and I suppose at least in some cases they are caching the
seeds. The Black-capped Chickadees are different. There are many more
of them, and they concentrate on the sunflower seeds, back and forth
in their little chickadee conveyer belt that I have described before.
There are always oddly colored partially amelanistic individuals that
allow me to have some idea how often they are coming. When the
sunflower seeds run out, the Black-caps land on the feeder and may
check each one of the four openings, but when they find no seeds,
most of the time they will then fly to the suet and grab a beakful or
two. They're not about to waste that trip. They then probably learn
that the seed feeder yields nothing, and I see the Black-caps going
back and forth to the suet more frequently.

There's a flicker feeding on suet at another feeder farther back in
the yard. They always knock pieces of suet off on the ground while
feeding, and many of the other species take advantage of it. There's
a Steller's Jay picking up those pieces right now. I've never seen a
chickadee do this, but Bewick's Wrens and Varied Thrushes do it, as
do gray squirrels and occasionally crows. Any leftovers probably go
to rats, possums, and raccoons at night. Let's face it, all wild
animals are optimizers.
-----
Dennis Paulson
1724 NE 98 St.
Seattle, WA 98115
206-528-1382
dennispaulson at comcast.net



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