Hawkwatching at Hawk Cliff
Whether you want to see large numbers of raptors or spot
a specific raptor species, it all comes down to the following
factors (Click a link to jump down the page to that
factor):
Time of Year
WHEN - The primary migration occurs at
Hawk Cliff during the fall season. However, raptors begin to migrate
by early August and will continue to migrate through to the end of
December. The peak volume of raptors occurs in September,
primarily due to the Broadwing flights which can hit 60,000+ birds
(or higher) in a day. On the other hand the peak variety of
species typically occurs in October when we can get all 15 of
the usual Hawk Cliff raptor species in a single day.
WHERE - The time of year can also affect
where you'll find the official counters setting up shop. For the
entire month of September and into early October we use the primary
site right down at the Cliff itself. However, as October wears on
the flight lines shift inland a few hundred metres to "Sharpie
Alley" which is just south of the ravine on Hawk Cliff Rd. By the
end of October and for all of November the main flight lines are
typically inland 3 or 4 km and we'll use an auxiliary site or sites
to the north of Hawk Cliff near the Fruit Ridge Line.
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Species
WHEN - The primary migration timeframes for
the different raptor species varies greatly at Hawk Cliff (click
this link or the chart image at right to see the
migration chart for ALL 15 species) For instance, if you
want to see Broadwings visit on the right day in
September and you could see thousands...but wait till later in
October and you'll miss them completely. To catch a glimpse of a Peregrine
cruising past, you'll want to visit at the end of September and into early
October...but don't wait till mid-October because they'll be
long gone! Take a look at the "Species
Info" pages for more details and charts on the migration
timeframes for each species.
WHERE - The flight lines for the
various raptor species are also quite variable and will at times
determine where the counters sit for the day. When it is Broadwing
time for example, the flight lines will almost always be just inland of the Cliff
site and visitors may want to sit further up Hawk Cliff Rd. or even
north of Dexter Line. However, for Bald Eagles, Osprey, Kestrels and
Peregrines the place to be is right at the Cliff. During the
2006 season we had close to 1,200 Kestrels on one day and almost
every one of them was right at the Cliff.
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Wind Direction / Wind Speed
WHEN - Typically for larger
flights the best wind direction has a north component to it and will
be very strong (click on this link or the image of the
wind direction pie graph at right to enlarge it). Experience has shown that during the fall season
strong northwest winds push the migrating birds down toward the lake. This
helps to concentrate the birds at the lakeshore and forces them to drop down
to avoid being blown out over the water itself, making for excellent
viewing.
Strong northeast winds are also favourable for migration but typically allows the birds to fly
higher taking advantage of a tail wind as they head west. There are often
large numbers of birds on such days but they a harder to view.
Not all favourable winds are from the north. If it's Peregrines you want to
see make sure to choose a day with very strong, even gale force
southwest winds (click on this link or the image of the
wind direction pie graph at right to enlarge it). Such
winds strike the cliff face and are pushed upward creating great lift along
the cliff. Many falcons, eagles and osprey take advantage of this lift to
migrate effortlessly westward along the lakeshore.
Click on the following links or the images of the
wind map or the
Port Stanley buoy
weather page (lower right) to see what
the current and forecast winds are for the Hawk Cliff area.
WHERE - The flight lines for the
migrating raptors are very much determined by the direction and
strength of the wind. If the winds are strong from the north then on
most days you'll find the flight occurring at or near the primary
Cliff site. If the wind is very strong from the southwest you can
also get good flights at the Cliff. However, any mostly southerly
flow will push the birds inland away from the lakeshore.
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Cloud Cover / Precipitation
WHEN - Visitors should always take note of the
amount of cloud cover (click on this link or the image of the
cloud cover map to the right) and potential for precipitation
(click on this link or the image of the
precipitation radar map to the right). In many
cases the largest numbers are seen within a couple of days after an extended
period of rain and/or fog and the passage of strong cold fronts. It seems that
the birds are held up at some point north and east of Hawk Cliff, unable to
pass through the poor weather conditions. Once the skies clear it's often
like a floodgate has been opened with several thousand (even 10's of
thousands) of raptors migrating by in a single day.
Good viewing calls for some kind of cloud cover as well. The best days are those
with large puffy cumulus clouds which are a great indicator of strong
thermals. These thermals are to key to raptor flight especially for soaring.
WHERE - The flight lines for the
migrating raptors can also be determined by the cloud cover. This
may sound strange but it has some basis in raptor flight mechanics.
Raptors use thermals (rising columns of warm air) to gain altitude
with a minimum of effort. On days where the cloud cover is lower and
heavy, the thermals tend not to set up as well and flights are
typically smaller. On days with much higher or broken cloud cover
the thermals are much better for lift and the birds take advantage
of this fact.
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Terrain
WHEN - N/A
WHERE - As previously, mentioned the falcons, Bald Eagles and
Osprey will follow the cliff edge
itself. The cliff forms a natural barrier to the SW or S winds and pushes
the air upward providing great lift for the birds.
Other raptors prefer open fields such as
the Harriers. Although the Harriers can be seen right at the cliff edge they seem to
like to hunt while migrating so will quarter a field looking for something
to eat. The buteos also prefer open fields to find the thermals they use
to gain altitude.
The Accipiters tend to follow tree lines or cruise over bush lots, most likely hunting as
well. The Goshawks especially follow the ravine area to the north side of
the Sharpie Alley field.
Of all the raptors the Golden Eagles seem not to use any particular terrain to their
advantage. Perhaps because they tend to pass through the area at typically
high flight levels.
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