Thanks to Paul Woodward and Bob Ringler for their comments.

On balance, I think that the Chickadee I saw and heard at Blue Mash 
Nature Trail today was most probably a Carolina Chickadee that had 
learned Black-capped vocalizations.  I saw many Black-capped 
Chickadees during a 10-day trip to New York State and New England 
within the last 2 weeks, so am relatively familiar with the 
appearance and sounds of this species.  Today's bird was similar in 
many ways.  Intriguing.  Let's see whether this winter season 
provides a big influx of Black-capped Chickadees to our area.

Mike B.
Bethesda, MD


At 07:29 PM 10/19/2010, Bob Ringler wrote:
>Mike,
>    I agree with Paul. Hybrids are probably extremely rare to begin with and
>are unlikely to be seen as migrants. Black-caps that occasionally irrupt
>into Maryland are mostly coming from Canada. Irruptions occur at irregular
>intervals and to varying degrees. Most irruptions in recent decades have
>been weaker than in the past. There has not been a major irruption of
>Black-caps into the state since 1983. Since they have been seen in
>significant numbers north of here I'll go out tomorrow near the state line
>and see if I can find any in northern Carroll County.
>
>On Tue, Oct 19, 2010 at 6:40 PM, Paul Woodward <> wrote:
>
> > Mike,
> >     I would be skeptical that the bird you saw was a hybrid.  I'm not sure
> > that hybrid chickadees ever move significant distances from their nesting
> > areas.  The black-caps that are moving south now are from the more northern
> > areas not the closer populations.
> >
> > Paul Woodward
> > Fairfax City, VA
> > 
>
>
>Bob Ringler
>Eldersburg MD

D.H. Michael Bowen
8609 Ewing Drive
Bethesda, MD  20817
Telephone: (301) 530-5764
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