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High-Tech Birdwatching
You would think we'd have it all figured
out by now. After all, we've been monitoring
the bird collision phenomenon for a
long
time. But we FLAPPERs still show up
in droves
on cloudy, misty nights when we're
sure there
will be hundreds of birds to be rescued,
only to find that there are more of
us than
our feathered friends!! Or there will
be
a night with birds everywhere and a
couple
of people frantically calling around
for
reinforcements!!!
Amazingly, the answer is right at our fingertips.
Anyone with access to the Internet
can punch
in www.intellicast.com/weather/buf/nexrad
and they're on a site that tracks weather
patterns over southeastern Ontario
centred
at Buffalo, New York...and just happens
to
pick up large movements of birds as
well!
On a favourably clear evening in May, say
around 8pm, check into this site and
you
won't see anything of note. Try again
at
9:30pm and you'll pick up a green blob
forming
around Buffalo, New York and another
around
Toronto. This green represents migratory
birds that have lifted off and are
starting
to move northward. A band of grey around
the edges of the green represents smaller
numbers of birds on the periphery of
the
major bird front. If you check in again
at
10pm you'll see that Lake Ontario is
partially
covered by a green blob. At midnight
the
lake is covered all the way across
to Toronto.
By 6am the birds are starting to land,
the
blob on the lake has vanished, but
green
areas are still visible at the north
and
south shores. (Some birds made it across
Lake Ontario that night, while others
will
cross at the next favourable opportunity.)
At 7am the green dots have vanished
as the
birds have all settled for the day.
How do we know that these green blobs represent
birds? John Black, a Brock University
Physics
professor with a long-standing interest
in
birds, assures us that the blobs correspond
with the data that he picks up on his
radar
screen, radar that's literally for
the birds.
John started a number of years ago monitoring
the movements of birds using sound.
He would
record the peeps and chips and assorted
calls
of birds migrating overhead during
the night
then proceed with the laborious task
of counting
the calls to try and determine how
many birds
were flying past. The method worked
well
for discerning species (with the exception
of flycatchers and vireos which don't
call
during migration) but it was difficult
to
come up with accurate numbers.
So John decided to try radar. Two years ago,
with a tracking device that had originally
been used at the Wood's Hole Oceanographic
Institute in Massachusetts, he set
up a station
on the roof of his building at Brock.
John
runs the radar all night long during
selected
migration nights. The conical radar
tracks
the birds flying within a one-kilometre
span
over the university from 200 to 1000
metres
above the roof. This is merely a sampling
of the birds moving across the Niagara
Peninsula
(there's nothing special about the
positioning
of Brock University from a songbird's
perspective!)
and does not take into account the
birds
that may be migrating at lower or higher
altitudes (even as high as two and
a half
kilometres above the ground).
So what happened this past spring when so
few birds were seen in downtown Toronto
or
even at the banding station on the
Toronto
Islands? Quite simply they took advantage
of the clear weather, came sailing
across
the lake and just kept on going. The
proof:
John had nights of up to 20,000 birds!
North of Toronto, near King City, John worked
with Norm Donaldson of the Atmospheric
Environment
Service of Environment Canada collecting
data on birds during the last two weeks
of
May this year. He looks forward to
continuing
this work in the fall when the information
gleaned from this specialized radar
station
is likely to be most useful to FLAP
as we
await the passage of the fall migrants.
Unfortunately,
the King City radar is not yet available
to the public.
Of course the disadvantage to the radar is
that it cannot tell what species or
even
families of birds are migrating. In
fact,
John says: "It could tell the
difference
between a 747 and a hummingbird, but
that's
about it for now!"
Nevertheless, the information is invaluable
to FLAP (it saves wear and tear on
our poor
bodies!)...and it reassures us to know
that
thousands of migrants made it safely
to their
nesting grounds this spring.
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