As I was leaving the house yesterday morning for my usual waterfowl count at
Cowan Lake, my wife urged me to stay gone for a while so she could get some
things done around the house.  So after I finished at Cowan, I looked in at
Harveysburg Road at Caesar Creek, Spring Valley and the Roxanna gravel pits.
 The result was an interesting comparison of waterfowl assemblages at these
three well-known locations.

At Cowan, the most numerous species were Canada Geese and Mallards. This is
quite usual, owing to the extensive habitat for these species in the shallow
east end of the lake.  Still, during migration, the lake often holds diving
ducks by the hundred.
 Saturday's leader was Lesser Scaup with a count of 83.  The peculiar
thing was the absence of Redhead and Ring-necked ducks, which usually
tally about the same numbers as the scaup.

At Harveysburg Road, I found Rick Asamoto looking at a flock of several
hundred ducks, about 75% of which were Redheads.  Most of the rest were
scaup with a smattering of dabbling ducks.  One Canvasback and a number of
ring-necks rounded out the total.  There were no coot, though there are
often several hundred at this location at this time of year.  The lack of
dabbling ducks is in keeping with the deep water habitat at Caesar Creek.
 The extreme seasonal variation in the water level prevents the emergence of
vegetation attractive to dabbling ducks.

At Spring Valley, there was a number of Ring-necked Ducks and smaller
numbers of dabbling ducks.  However, American Coot outnumbered all the duck
by a factor of about three.  In past years, Spring Valley has hosted very
large numbers of dabbling ducks in migration, many more than were in
evidence on Saturday.

At the Roxanna gravel pit, there were only twenty Canada Geese and a couple
of ducks on the back side of the lake that I was not able to identify.

The striking aspect of these observations is the lack of consistency in
numbers and species composition from place to place.  It suggests a strong
stochastic element in waterfowl migration choices.

Cheers,

Bob

--
Robert D Powell
Wilmington, OH, USA
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Nulla dies sine linea

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