Subject: Marymoor Park Report (Redmond, King Co. WA) 5/30/2001
Date: May 30 19:50:53 2001
From: Michael Hobbs - Hummer at isomedia.com


RE: Marymoor Park Report (Redmond, King Co. WA) 5/30/2001Tweets -

Steve Aubert asked me why I said Black Swift were to be expected on overcast
days in June at Marymoor. Here are ALL of my Black Swift sightings for
Marymoor with count, and weather:

23-May-96 100 Overcast, some rain.
27-May-97 10 Cloudy, very high humidity. Some drizzly mist.
30-May-96 15 Sunny, turning cloudy.
30-May-01 40 Heavy overcast, with a little drizzle
31-May-00 75 Heavy overcast, with drizzle turning to hard rain
05-Jun-97 50 Mosquitos! Pretty cloudy.
11-Jun-98 100 Cloudy but pleasant. Light could have been better.
13-Jun-91 ? No data
14-Jun-00 6 Cloudy and windy, but no rain.
18-Jun-98 100 Cloudy, showers.
19-Jun-97 50 Cloudy, a little rain. Voracious mosquitos.
25-Jun-98 20 Cloudy, dark, cold, windy, a bit of drizzle.
29-Jun-95 2 No data
04-Jul-96 7 Overcast with some breaks. Temp. in low 50's and
rising.
10-Jul-97 75 Mostly cloudy, calm. A bit of drizzle.
18-Jul-96 25 Cloudy, rainy, cold. Lots of mosquitos.
19-Jul-00 2 Partly overcast, 55F
18-Aug-95 100 No data
07-Oct-99 4 Pretty dark and quiet, mostly quiet because of wind.

Out of 60 trips between May 23 and July 19, I noted 18 days of sunny/high
overcast weather (1 with BLSW), 26 days with clouds, drizzle, and maybe rain
(13 with BLSW), and 16 days where I didn't note the weather (2 with BLSW).
These 16 were likely to have been unremarkable weatherwise (hence no note).

The correlation with cloudy (though not necessarily unpleasant except for
mosquitos) weather seems clear.

I believe this association with the weather has been noted by others, and the
theory explained to me by Brian Bell is that when it is cold and cloudy up in
the Cascades (where the Black Swifts nest), they come down to the lowlands to
find insects over lakes.

== Michael Hobbs
== Kirkland WA
== Hummer at isomedia.com
== http://www.scn.org/fomp/birding.htm