Tweeters,

A lot of the effort spent at the base of waterfalls in Washington and
Oregon in 2003-05 was aimed at expanding the known breeding range of
the Black Swift in these two states.

Here's a link to the most specific map of the Black Swift's nesting
range in Washington that I've come accross. It includes a spiffy photo
by Dennis Paulson.
http://www.birdweb.org/birdweb/species.asp?id=257

The distribution in Oregon is more mysterious. We have so far only
found them in the Cascades west of the Three Sisters. Sibley has it
correct on his range map. Kaufman has got it too far north, and really
messed up on Washington. The National Geographic guide book looks like
Kaufmans and their reference atlas is also off. They swifts are also
suspected of nesting in very NE Oregon in the Wallowa Mts., but as far
as I know we haven't caught them at it yet.

What was discouraging for the many Portland observers that went looking
for Black Swifts at all those spectacular falls located in the Columbia
Gorge (like Multnomah) was that they didn't see any. There are also a
goodly number of nice falls on the Washington side of the Columbia and
we've been striking out there too. Perhaps you can guess the next
question.

Why is this so?

I don't believe you are going to be able to Google up this one.
Surprise me.

Larry Schwitters
Issaquah