Remsen, J.V. 1978 Mountain Bluebird Sialia currucoides Cameron Parish, Louisiana Oct. 28 I near Holly Beach - probably an imm. ♂. Similar in size and shape to Western Bluebird but sleeker, slimmer, longer wings + shorter tail. Plumage description: wings and tail striking sky blue; crown blue but paler than wings and tail; nape and upper back grayish; face blueish contrasting with grayish throat and breast; flanks and undertail coverts very white, striking at a distance; uppertail coverts and rump very blue contrasting strongly with pale grayish flanks and undertail coverts. We watched the bird for 15+ minutes in good light at 100 yds. through telescope as it sallied to the ground from wooden fence posts bordering a power-station. It occasionally hovered briefly over the ground before dipping to the ground. Unlike any plumage of either Eastern or Western Bluebird, there was absolutely no trace of any rusty or brown tones. The hue of blue was paler, more towards turquoise than either Eastern or Western.