Mountain Bluebird in New York

Mountain Bluebird (Sialia currucoides) in New York

Mountain Bluebird is a rare visitor to New York State with less than 10 accepted records (Levine, 1998). One individual was discovered on the grounds of SUNY Purchase, Westchester County during the Greenwich 1998/99 Christmas Bird Count (Sunday 19th December, 1998). It frequented an area of roughly cut grass, edged with small trees and bushes.

Here are a series of photos of this bird taken on the morning of Tuesday 22nd December 1998 which was very windy (All images copyright © of Angus Wilson). The bird called several times giving a thin single-note whistle. It fed by perching in exposed branches before flying out into short stubble to pounce on prey items. Sometimes it hopped around in the grass stubble, occasionally perching on short stems or hovering for sustained period (like a little blue Kestrel!).

Figure 1. Dorsal-view with head turned. Semi-circle of white behined the eye; orange-buff throat; white edges to wing coverts and the tertials. Telescopic foreshortening makes it difficult to see the long wings.

Figure 2. Side-view on ground. A sleek bird without the dumpy posture of Eastern Bluebird. Note the slight buff wash to the gray flanks and bright white vent region and undertail coverts - this is consistent with fresh plumage and becomes grayer with time (Zimmer, 1985).

Figure 3. Side-view perched. Spent quite a lot of time perched in trees surrounding the field. Would drop down to snatch prey in the short grass. Note the white edging to the flight feathers (primaries, secondaries and tertials) and wing coverts. The turquoise blue coloration to the tail and flight feathers is most obvious here.

Figure 4. Head-on view. Note the strong wash of orange-brown on the throat and breast forming is discrete border with paler (off-white) belly and flanks. The white-edging to the alula is very striking.

References:
Kaufman, K. (1992) 'Bluebirds' American Birds 46: 159-162.
Levine, E. (1998) 'Bull's Birds of New York State' Cornell Unversity Press.
Pyle, P. (1997) 'Identification Guide to North American Birds - Part 1' p390-391. Slate Creek Press. Zimmer, K.J. (1985) The Western Bird Watcher: an introduction to birding in the American west. Prentice-Hall