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Greg Lasley Nature Photography
All of the images are copyright-protected and have been digitally watermarked and
their display here in no way implies consent for any form of distribution or reuse.
Refer to my image use page if you are interested in purchasing rights. Thanks!
The identification of
Mottled vrs. American Black Duck in Texas is a little understood
or appreciated field problem for observers. One of the problems
causing confusion is that all of the standard field guides illustrate
the nominate race of Mottled Ducks which in the U.S. is most
commonly found in Florida and the eastern Gulf Coast. Birds from
most of Louisiana and Texas are of the maculosa race commonly
found in Mexico. Texas Mottleds can be every bit as dark as Black
Ducks, show purple speculum (depending upon light angle), and
have gleaming white wing linings. Our Mottleds can vary from
pale to very dark birds. There are a number of accounts describing
this in the literature, but not in standard field guides. Basically,
to ID a true Black Duck in Texas takes a very careful study of
the feather edges of the scapulars, flank, back, etc. Mottleds
show buffy internal markings on these feathers with a buffy edge,
while Black Ducks lack any internal markings on these feathers
and have very crisp, fine,
lighter edges. There are some slight differences in the throat
and facial markings as well, but these are subtle and very hard
to see
unless an extremely close view is obtained.
I have posted several photos here to illustrate some of these
points. I took these photos several years ago when I was considering
writing an article concerning these field ID problems. The mounted
Mottled Duck specimen at right and below was shot by a hunter
in Chambers Co., Texas in the late 1980s. Note the fairly broad
buffy edges to the scapulars and back feathers. Note the blue
speculum color in the upper photo and the purple speculum color
in the below photo of the same mounted bird. The angle of the
light can cause a great deal of variability.
Note the generally unstreaked chin of the Mottled Duck immediately
below.
Note that this is not a particularly dark Mottled Duck; many
in Texas are considerably darker.
Scroll down for photos of a mounted American Black Duck.
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