Subject: Re: Fidalgo Bay
Date: Jul 10 10:35 PD 1995
From: Michael Price - michael_price at mindlink.bc.ca


Hi Tweeters,

On July 10 Mike Patrick says:

>this is the first time I've seen Great-blue Herons flock)! Beautiful.

In the mid-Seventies, I was out at Point Grey in Vancouver BC in early
September and saw a dense kettle of 38 enormous birds in full soar circling
very slowly northward *high* over Burrard Inlet where it widens and joins
the Strait of Georgia. It's about 5 km wide at that point. I tried to fit
the silhouettes into every known eagle, vulture, buzzard, stork, pelican, or
crane profile I could think of with no success--they kept looking like Great
Blue Herons (GBHE).

A look through the bins showed they were *all* GBHE. There were no eagles in
the immediate vicinity, not that the many GBHE's in the area ever did
anything but almost completely ignore the many wintering and few locally
breeding eagles. The only interactions I ever saw between eagles and herons
would be the occasional grouchy exchange of views regarding possession of a
few meters of low-tide shoreline; the herons to feed, the eagles to loaf. I
couldn't tell if all were adults or whether juveniles were involved. The
kettle moved northward toward West Vancouver, breaking up after at least
*five minutes* of dedicated soaring as individual birds peeled off to head
for various feeding sites along the West Van shoreline.

While I've seen individual GBHE's circle in full soar for a circuit or two
or even three, in my experience, this kettling incident is unique, and I
have no explanation for it. Conceivably, these birds could have been a
migrant flock (do migrant GBHE's flock or move as individuals/ffamily
groups?), though early September seems awfully early, and there's not much
of a migratory push of GBHE's through Vancouver BC (what flux there may be
is masked by local abundance) anyway.

Michael Price
Vancouver BC Canada
michael_price at mindlink.bc.ca