Hello All,
Keith is right about the regular occurance of Broad-winged Hawks at
locations with steady coverage in the Cascades (Chelan Ridge, Entiat Ridge,
Bonney Butte in Oregon). This movement in September/early October has been
known for over a decade. Very recently there have been a growing number of
records from the Columbia Basin, from Vantage to Hooper.

Even more interesting are a significant number of BWHA that have been
observed crossing the Straits of Juan de Fuca from southern Vancouver
Island. I'm not sure when these birds started being detected. These birds
obviously pass though western Washington somewhere west of the Cascades,
probably mostly west of Puget Sound where there are fewer birders. A couple
weeks ago I was looking at maps of one Vancouver Island spot which reported
many BWHA this fall, and if those birds glided due south they would go over
Salt Creek County Park, but perhaps they are swept one way or the other by
the prevailing winds.

Recent records that could reflect the edge of this movement include one on
Whidbey Island a few years ago, and one that I saw in Pierce County on 8
October this year (though the latter is perhaps more likely part of the
Cascades movement). More records from the Olympic Peninsula and perhaps the
outer coast would be expected with more vigilance out there.

Where these birds originate is also an interesting question. Broad-winged
Hawks have been steadily increasing as a breeder in central BC from what I
hear, but I'm not sure of the population numbers.

Charlie Wright
Bonney Lake, Washington