>On 26 Jun 00, at 13:04, Blake Iverson wrote:
>
>
>> The reason your hummers left Jacki is because they are nesting
>>and if
>> they have young they switch from nector to insects. They do feed on both but
>> insects are a big part of the diet for the young, nutrition etc. Don't
>>worry,
>> they'll be back in a month or so.

Tweets,

the above comment doesn't quite fit what's going on with rufous hummers, at
least in my neck of the woods. According to Ehrlich et al in The Birder's
Handbook, a rufous hummer incubates eggs for twelve to fourteen days, and
the birds fledge after another twenty days. So it takes roughly a month to
get the kids out the door. Hummers arrive here in mid-March (the 20th this
year), and even if they take a month to set up shop and get down to
business, by the end of May, they've fledged. The Handbook also says that
they will occasionally have two broods; I'm inclined to think that the
dominant female here did that this year, but those birds fledged last week,
and this week things are pretty quiet. That's the usual pattern here; by
July the hummers are done and gone. Rufous hummers are already showing up
in Arizona, btw, on their way south.

Another observation: the birds never completely stop coming to the feeders
here, even at the height of breeding. Traffic drops off noticably, but they
still come, just less frequently.

It's fascinating that Jacki writes that hummers don't show up in
Woodinville until May, and then stay until August; I can only guess at
what's happening there. Two possibilities occur to me: either they've
already bred elsewhere, and have moved there to have a second brood, or
they're all migrants and aren't breeding there at all. I'd like to hear
from anyone who has additional insights...

Rob Saecker
Olympia, WA
rsaecker at thurston.com