On Saturday, Sept 1, I stood on a steep 75-foot-high bank on Whidbey Island
overlooking Saratoga Passage. Beneath me, two GB Herons flying along gravel
beach shoreline were overtaken by a Peregrine Falcon only a few feet above
them. The falcon dove on one of the herons, coming within about a foot of
it before zooming on ahead.

I asked ornithologist friend, Stan Temple (U. of Wis. emeritus prof) about
the ridiculous move. His reply: "Peregrines can be 'playful,' and when
something to eat isn't the target they seem to 'enjoy' showing off their
aerial superiority. I've seen them target turkey vultures and even hang
gliders with impressive dispays of aerobatics. Although that's undoubtedly
what you observed, European and Indian falconers in the past did train their
birds to bring down herons and cranes, so your herons may have taken the
mock attack a bit more seriously."

Ray White
Edmonds