Paula Grieef forwarded a photo by Gerald Machnee (see below) of the late Selkirk hummer to me today and my immediate gut reaction upon opening the jpeg and noticing the small, short-tailed GISS was Calliope Hummingbird. the flank colouration also seemed consistent with this species. Note the size of the bird against the feeder.
I eventually got the phone number of the home owner and she permitted me to visit. Shortly after we arrived, the hummer appeared and the small size and short-tail were immediately apparent, the features seeming to confirm my tentative identification as Calliope Hummingbird. The following photos exhibit the features. I apologise for the terrible quality of the photos due to the extremely difficult conditions (some were taken through glass as well). Click on any photo to view in larger format.
The first two photos show that the folded wing is slightly longer than the tail:
The short-tailed GISS was apparent even in flight
This photo by Donna Martin show the undertail nicely. Note how short the fanned tail is, the buffy wash on the base of the outer recs, the short "spade-shaped" central recs (we tried our best to photograph this feature and I apologise that we don't have better shots)
A view of the tail from above showing the extent of the white:
There was buff colouration on the flanks and breast sides, creating the appearance of an indistinct white bar across the vent and also across the chest. This shows in the following shots:
These next photos again show that the wings were longer than the tail, the buffy colouration on breast sides and flanks and the undertail pattern.
The only strike against this being a Calliope that I can think of is the lack of any elongated gorget streaks but I assume these develop with age and may not show on an immature bird such as this ( I believe immature male). I am now completely confident this is indeed a Calliope Hummingbird. Expert opinions are most welcome, either here or by email to the Manitobirds list-serve.