North-western Ecuador, mainly on volcanoes Pichincha and Atacazo, but also known from Imbabura; recent records only from ridge crests of Frutillas, Yanacocha, Cerro Alaspungo and Cerro Pugsi.
 
Population
Estimated population is 210 - 268 (2010) and decreasing.
Status CR
Habitat destruction and degradation through production of timber and charcoal, cattle ranching, crop production, are the main threats.
For more information see BirdLife International Species Factsheet.
Voice
Mostly silent, but sometimes gives a weak 'tzeet tzeet' after taking flight.
Black-breasted Puffleg (Eriocnemis nigrivestis) [XC349702]
by Mery Jui\u00f1a from Pichincha: Verdecocha, Ecuador (begging call, juv male and juv female)
Black-breasted Puffleg (Eriocnemis nigrivestis) [XC349703]
by id from Pichincha: Verdecocha, Ecuador (call, take-off call)
Similar Species
Male unconfusable, but female resembles Glowing Puffleg (Eriocnemis vestita), but is less cinnamon below, more bluish uppertail-coverts that glitter less strongly, and belly has more extensive whitish fringes.
References
See References.