Subject: Allen's Hummingbird
Date: Jun 3 10:52:26 2004
From: Mike Patterson - celata at pacifier.com


In this case, positive assortment is achieve (theoretically
at least) by recognition of flight displays, sounds produced
during those displays and apparent differences in breeding habitat
preferences.

Suspected hybrids are controversial. Some fairly good studies
of recaptured individuals suggest that the green-backed condition
in Rufous Hummingbirds is age related and not an intermediate or
hybrid character. Intermediate characters would include tail
feather measurements inbetween the two species, mixed structural
characters in the shape of tail feathers and mixed behaviors
particularly in the display.

There does not appear to be an increase in intermediate birds in
the zone of sympatry, but not nearly enough effort has been put
into the question to make any concrete claims. Most intermediates
have been reported from places like Louisiana and Alabama where
constant effort winter banding of hummingbirds happens in a coordinated
way, but at this point there is no way to determine the origin of those
birds unless they are recaptured up here somewhere.

We attempted to put together a team of banders this year to go
spend a couple of weeks in Curry Co., but there were funding
issues. Hopefully, we'll be able to put something together for
next year

--- original message ---
RE: Allen's Hummingbird
From: "Guttman, Burt" <GuttmanB AT evergreen.edu>
Date: Thu, 3 Jun 2004 10:10:44 -0700

So the critical question is, What happens
in that range? The only difference between the two seems to be in the color
of the back--green or brown. Are there apparent hybrids in that range, with
plumages of some mixed color? But if the color were determined by some gene
with one allele completely dominant and the other recessive, it would really
be hard to tell from casual observation whether hybridization occurs. And
the females of the two types are supposed to be impossible to
distinguish in
the field. Anyone have useful information to contribute?




--
Mike Patterson
Astoria, OR
celata at pacifier.com