Willow Flycatcher (WIFL) is a rather uncommon fall migrant in Santa Cruz
County (SCZ). The ability of birders to detect and identify WIFL (and other
members of its genus) in our region has greatly improved in the last 10-15
years, thus fall migrant WIFL were not even reported annually in SCZ prior to
1986. Since then, however, 1-20 individuals have been reported each fall
(average 6.8 birds). (Note: there was no consistent, intensively run banding
operation in SCZ during this period).

Fall migrant WIFL have been found in SCZ from August 23 to October 22.
Ninety-five records of fall migrants were reported to the county's record
keeping system from 1986-1999 (n=14 years). Of these, 79% occurred between
August 21 - September 20, and 57% during the peak period of September 6-20.
The average date of the first fall report was September 1 (± 9 days), while
the average date of the last fall report was September 29 (± 12 days).

WIFL has normally been found singly, although occasionally two or three have
been found in the same area on the same date. Individuals sometimes linger
for several days. Nearly all WIFL have been found within two miles of the
coast, or rarely further inland in the Pajaro Valley. They are usually found
in deciduous riparian habitat.

** Summary of timing of fall WIFL migration 1986-1999.
 
 

Period	# records	% of total (n=95)
Aug 21-25	2	2.1 %
Aug 26-31	12	12.6 %
Sep 1-5	9	9.5 %
Sep 6-10	21	22.1 %
Sep 11-15	15	15.8 %
Sep 16-20	18	18.9 %
Sep 21-25	4	4.2 %
Sep 26-30	3	3.2 %
Oct 1-5	7	7.4 %
Oct 6-10	3	3.2 %
Oct 11-15	--	--
Oct 16-20	--	--
Oct 21-25	1	1.1%