Some readers may be aware of the problem of interbreeding between Mottled
Ducks and feral Mallards.  So far this season I have examined about 10
"Mottleds" at Guana River WMA.  Only two of these have been what appeared
to be pure Mottleds.  The others have shown signs of
hybridization.  Although the sample size is small, that's a fairly high
proportion of intergrades.

I am surprised that there are virtually no reports of intergrades posted to
this list.  Although some of the characters of intergrades can be subtle,
it should be possible to ID them in the field, given adequate
views.  Things to look for -- All of the Mottled-like intergrades that I
have examined have had extensive dark streaking on the cheeks.  On a pure
Mottled the cheek should be mostly clear buffy, with few if any
streaks.  Although some males may clearly look intermediate with many
Mallard characters (partially green head, partially rusty beast), I have
handled two adult males that the only apparent Mallard character (other
than cheek streaking) was curled upper tail coverts.  The presence of a
white bar above the speculum (i.e., prominent white tips to the greater
secondary coverts) seems to an inconsistent character for intergrades.  I
have seen it on only one bird.

Go forth.  Find and report muddled Mottleds...

Noel Wamer
Jacksonville, FL

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