Hi all,

I went to Monroe this morning before sunrise to see the swifts emerge from
the chimney at the elementary school. As an anchor point for time, official
sunrise in Seattle this morning was 6:31 am.

I expected them to all emerge on some signal--time, temperature, light, or
some such. Instead, starting at about 6:30, swifts from elsewhere began
arriving and circling, groups of three to 10 at first, then larger and
larger groups. A good many of these birds entered the stack, especially
most of those arriving during the first 20 minutes or so. At 7:00 I saw the
first two birds emerge.

At 7:17 the clouds were getting bright, with a bit of blue overhead.
Increasing numbers of birds were arriving from elsewhere, with some entering
the stack.

At 7:43, sunlight broke through the clouds in the east, with filtered sun
continuing from then on.

At 8:07, birds began emerging. I rather expected them to fly off about
level with top of stack. Instead, most dove for 10 feet or so once clear of
the rim. Between 8:07 and about 8:33, birds were generally emerging, with
many circling about but also with a good many going back into the stack.
After 8:33 I saw no birds emerge but some go back in.

I quit observing carefully at 8:38, at which time a group of 20 or 30
arrived and circled with perhaps 8 or 10 going back in. At this point I
diverted my attention to "A Birder's Guide to Washington,? and when I looked
at the stack again at 8:45, there were no swifts in view.

Planning to estimate how many birds were in the chimney overnight, I took a
video clip every minute, planning to count 5 second's worth and use it as
the rate of emergence for 30 seconds on each side of the minute mark.
Adjusting for how many went out the far side where unobserved should give a
fairly decent estimate of how many EMERGED, But, with birds still entering
after no more were coming out, it's obvious that an unknown number stayed
in. (Perhaps they wanted to rest after breakfast or simply were taking it
easy on a holiday weekend.)

Observations left more questions than answers. In the next day or two, I
hope to post en estimate of the number emerging.

Al Wagar
Shoreline
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