Count Protocols
The naked eye, binoculars and spotting scopes
are used to scan the sky for migrants. Spotters
are often used to help the official counter
locate birds. When a raptor is observed,
a series of decisions is made.
First, in what direction is the bird heading?
Only birds moving to the south or southwest
are defined as migrating.
Any bird not moving into this quadrant is
not counted.
What is next?
Once it has been determined the bird is migrating,
it is then identified as to species using
the standard field identification techniques
(shape, color, pattern, wing beat cadence,
behavior, etc.). If it is not possible to
identify the bird, it is recorded as "unidentified."
If possible, age and sex are also noted.
Official Tally
The bird is officially tallied only after
it passes south of the observer. Any bird
that does not pass that point is not counted.
Each migrant species that is observed is
recorded on a tabletop clicker with one button
for each of 16 species. At the end of the
hour, the species totals are documented and
the clicker is cleared.
For Broad-winged Hawks, the counting is more
involved.
Broad-wings save energy by riding thermals
for lift. At times, hundreds or thousands
of birds are using the same thermal. The
birds are far too difficult to count while
in these "kettles" which can look
like a tornado swirling with birds.
Conveniently for counters, however, when
the birds reach the top of the thermal, they
glide out singly or in smaller numbers (often
referred to as "streaming out").
As they stream out, the birds can be counted
one at a time on our hand-held clickers.
If necessary, they are counted 10 at a time
(one click represents 10 birds). If there
are too many birds for this, a block count
method can be used on the stream (example:
if 40 birds are in one field of view in the
binoculars and 25 fields of view are required
to scan a given group, 1000 birds are tallied).
Bald Eagles and Osprey
Before a Bald Eagle or Osprey is officially
tallied, it must demonstrate a migratory
pattern as opposed to a behavior indicative
of a transient or local bird.
Birds are not counted as migrants if they
are:
- in view for extended periods of time ("hanging
out"),
- actively hunting, or
- flying "the wrong way".
Eagles and osprey are counted if they are:
- using thermals,
- flying a straight course in the correct direction
or
- at a very high altitude are recorded as migrants.
Identifying individual birds by sex or age
assists with the migrant/transient documentation.
This procedure allows for a more conservative
Bald Eagle and Osprey survey.
Count Sites
It is important to note that two sites --
the Boat Launch at Lake Erie Metropark (LEMP)
plus the headquarters of Pointe Mouillee
State Game Area (PMSGA) about 2 miles to
the south -- can and will be used simultaneously
under certain conditions. This does not mean
that birds are "double-counted."
The positions of the north and south observation
sites relative to the east-to-west migration
path over the shoreline prevent it. (See
map).
For example, raptors recorded at PMSGA, the
southern site, will never be seen at LEMP.
Coming ashore at PMSGA, they disappear into
the skies of Monroe County west or south
of the count site and will never be seen
again by SMRR during this migration. However,
a raptor observed at LEMP, the northern count
site, will do one of two things:
- continue further inland before adjusting
to a more southerly course or
- swing immediately to the southwest.
If it swings to the southwest, the geography
of the shoreline brings the bird over land
behind the PMSGA count site. As stated above,
the birds are counted only when they cross
the counter's line, but not if they appear
suddenly behind the observers.
Simultaneous use of the sites is irregular
at best and depends on wind direction (see
weather section). The majority of the season's
hours come from the LEMP site. Also, all
numbers are recorded separately and can be
analyzed separately. Numbers posted on the
Internet are combined for the sake of simplicity.
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