Hi Tweets

at Barbara Deihl asking of Martin Muller:

> I wondered if you caught
any Peregrine/Northern Harrier interaction on video?

Not on video, but I once saw an adult Peregrine slug a Green-winged Teal at
Boundary Bay, BC, and a female Northern Harrier came over and cross-checked
it off the kill. After a bit of a slanging match, the 'grine went off to try
again while the harrier settled down to feed on her ill-gotten prey.

And somewhere about 1980, on the Martindale Flats in Saanich on southern
Vancouver Island with Michael Shepard and Michael Force (forgive me if I've
omitted anyone, so long ago in those halcyon days), we watched a Northern
Harrier make a kill of something I don't remember, go to ground with it and
a wintering grey-morph Gyrfalcon (lifer Gyr!) came whipping over to try to
'talk the Harrier out of it'. What happened next was amazing.

Picture this from where we all were, about fifty feet away: the harrier was
on the ground under some cottonwoods, prey in its talons. The Gyrfalcon
walked up to the harrier until they were quite literally chest-bumping each
other. Each reared up and tried to stare the other down, like two boxers up
in each other's faces just before a bout. Oh, the falcon's intimidation! Oh,
the harrier so not backing down! Chest-to-chest, each reared to their full
height in the confrontation, yet the harrier did not surrender its prey to
the falcon. After thirty seconds or so of tense stand-off, the falcon
decided 'aw, crap, too much trouble', backed away and flew off. And we were
left with a very new appreciation of a harrier's ability to stand its ground
against what I would have considered a very superior competitor.

That's when it dawned that there's much more to harriers than we often
assume. We may even have to consider them a kind of apex predator in their
particular habitat. After all, if they can rob Peregrines and stand up to
Gyrfalcons and get away with it, who's left as a potential competitor for
the top-predator role? Only Short-Eared Owls, really. But, whereas the
harriers will hunt throughout daylight hours (and with those facial disks,
why should they stop when the sun goes down?), the owls usually are active
only during heavily-overcast days or early morning/late afternoon and
evening. Advantage, harrier.

Doesn't stop there.

About ten years later, in a field at the entrance to the Reifel Bird
Sanctuary, another grey-morph Gyr (and, given its attitude, I'm tempted to
say, 'sitting at the bar drinkin' raw whiskey in a surly mood') decided it
just didn't like the stinkin' looks of a nearby harrier and began trying to
fly it down. Ten minutes later, after some of the most amazing
chase-and-escape flying I've ever seen---and I got there my first real
appreciation of the gyrfalcon's blinding level-flight speed and the
harrier's incredible agility---they separated, went and sat separately, the
gyr in its tree, the harrier on the ground, and peace once again descended
on the field.

To conclude: don't take harriers for granted (they're a lot tougher than
they look); and don't be too romantically over-awed by falcons: they can be
as dangerously sexy as a Euro film star and still be craven in the face of a
determined harrier.

Michael Price
Vancouver BC Canada
loblollyboy at gmail.com

Every answer deepens the mystery.
- E.O. Wilson
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