Steve Preston writes:

>my parents asked if there is any reason to be =
>concerned about keeping the feeders out too long and delaying the =
>hummingbird's migration.
>
>Does anyone care to comment on this topic?

Steve, the short answer is no, there's no reason to be concerned.

In all but one of the North American humminngbird species we're likely to
encounter here in the Far West, it's duration of daylight that cues
migration. Food availability has little to nothing to do with them staying
or leaving, except that they'd prefer to migrate on a full belly if possible
and tank up along the way at feeders. Your parents can leave the feeder up
until there ain't no more hummingbirds (maybe as late as mid-October, but
that's just a guess; I don't know the migrational schedule of birds
migrating through Colorado--that's what it would be for Vancouver BC here on
the West Coast, though) as a refuelling point for migrating hummers with
clear conscience and untroubled sleep.

Three exceptions to this: first, any hummer staying at a feeder in mid- to
late October and later is likely too sick or injured to join the migration,
and is a good candidate for rehab. How to catch something so fast? A
technique I've heard of requires a hummerfeeder and a budgie cage. Once the
bird has become used to the feeder, put the cage near the feeder's usual
location, put the feeder inside the cage and close the door with a long rod
or stick once the hummer's inside. Some Rufous Hummingbirds (particularly
juveniles) can be very late (late Sept/early Oct to mid-Oct.) as they may be
coming from a *long* way north (western mid-Alaska, Yukon, NWT) and
sometimes so high up that Spring and Summer don't arrive until late July and
August.

Secondly, you may have a 'wrong-way' or 'mirror' migrant. Some individuals
of southern species may get crossed migratory instructions and head north.
By definition, this would be a rarity: i.e., the Costa's Hummer they had in
Alaska some years back fairly late in the year.

Third, and this one's a kicker, on *this* side of the mountains at least one
may get an Anna's Hummingbird coming to a feeder late in the year. This
species is pretty non-migratory, but wide-wandering. It winters where it
finds itself when the days start to get short (and maybe it's daylight
duration that triggers it to sit tight--can anyone comment on this?). It
won't survive without access to unfrozen sugar water available *every* day,
and even then it can be iffy. Over the last several decades they've extended
their range and are now permanent residents N along the Pacific Coast from
their original range in northern California to southern British Columbia.
The main factors in their spread were 1., there's far more urban gardens,
and 2., more hummingbird feeders. As long as they have daily frequent access
to unfrozen sugar water, most can survive surprisingly bitter winter
conditions for up to several weeks. A few years ago, Vancouver BC's
population of Anna's Hummingbirds came through almost unscathed through a
very bad (for Vancouver BC) winter though there was subzero (Celsius *and*
Fahrenheit) temperatures and deep snow on the ground for an unusually long
five or six weeks.

I don't know if they've visited Colorado, but my hunch is that the Colorado
winter would get the better of them, feeders or no.

Hope this helps your folks feel easier.

Michael Price
Vancouver BC Canada
mprice at mindlink.net