Oliver,

Anna's Hummingbirds are nonmigratory. All the other North American
hummingbirds are migratory, but not this one. Our birds would not be
to the south of here if we didn't feed them this winter. They are
here whether we feed them or not, so we haven't changed a thing about
their behavior.

However, we have changed the DISTRIBUTION of this species over time
by the proliferation of hummingbird feeders all over the West, so we
are ultimately responsible for them being here. From an original
distribution in California and southern Oregon, they have spread
widely to the north and east. There are doubtless thousands of Anna's
Hummingbirds in western Washington now, and I suppose thousands of
feeders to feed them! If you discontinued your feeder for a week by
going out of town, your birds would very likely find another nearby
feeder. We regularly see our hummers leave the yard in an apparent
long-distance directed flight, and I'm sure they're just going to the
next feeder. When we go away for a couple of weeks, they are still
here when we return, even though they haven't been fed in our yard
during that time. And as you say, there are probably not enough
flowers around to feed them.

And one more thing. There is little question that the proliferation
of feeders must have some effect on hummingbird populations, but it
doesn't seem to have changed their migratory behavior much. A lot
more stray hummers turn up at winter feeders in the East, but they
represent a tiny part of the populations of their species. The hordes
of hummers that pass through southern Arizona in the fall, for
example, still disappear in the winter and presumably are heading on
south to their Mexican feeding grounds. I've always been amazed that
they didn't just stay in Arizona, but they don't. There are
essentially no Black-chinned or Rufous Hummingbirds in Arizona in
winter, although they swarm around feeders there in August and
September. Why don't they stay? I suppose their genetic programming
continues to work.

Dennis

On Dec 16, 2008, at 12:01 PM, tweeters-
request at mailman2.u.washington.edu wrote:

> Date: Tue, 16 Dec 2008 14:59:23 -0500
> From: "Oliver May" <omayo at soon.com>
> Subject: Re: [Tweeters] Hand Warmers and Hummers?
> To: tweeters at u.washington.edu
> Message-ID: <20081216195923.D350F606861 at ws1-4.us4.outblaze.com>
> Content-Type: text/plain; charset="utf-8"
>
>
> Steve Compton Wrote
>> ----- Original Message -----
>> From: scompton1251 at charter.net
>
>> Birders,
>>
>> Most experts now believe that feeding hummingbirds in the winter
>> does not alter their migration or wintering patterns.
>>
>> Steve Compton
>> Greenville,SC
>
> What studies or logical theories support your statement,
>
> And how could feeding hummingbirds in the winter not change their
> wintering or migratory patterns?
> If you weren't feeding them they would be somewhere far to the
> south of Washington where plants ARE flowering, probably in Arizona
> or southern California
> Because when I look outside of my window I don't see any flowers
> providing nectar for hummers, just man made hummingbird feeders
> and now they have handwarmers attached to them.
> How could that NOT change Hummingbirds natural behavior?
> Can anyone provide a theory for that?
>

-----
Dennis Paulson
1724 NE 98 St.
Seattle, WA 98115
206-528-1382
dennispaulson at comcast.net



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